On the reliable use of satellite-derived surface water products for global flood monitoring
NASA Astrophysics Data System (ADS)
Hirpa, F. A.; Revilla-Romero, B.; Thielen, J.; Salamon, P.; Brakenridge, R.; Pappenberger, F.; de Groeve, T.
2015-12-01
Early flood warning and real-time monitoring systems play a key role in flood risk reduction and disaster response management. To this end, real-time flood forecasting and satellite-based detection systems have been developed at global scale. However, due to the limited availability of up-to-date ground observations, the reliability of these systems for real-time applications have not been assessed in large parts of the globe. In this study, we performed comparative evaluations of the commonly used satellite-based global flood detections and operational flood forecasting system using 10 major flood cases reported over three years (2012-2014). Specially, we assessed the flood detection capabilities of the near real-time global flood maps from the Global Flood Detection System (GFDS), and from the Moderate Resolution Imaging Spectroradiometer (MODIS), and the operational forecasts from the Global Flood Awareness System (GloFAS) for the major flood events recorded in global flood databases. We present the evaluation results of the global flood detection and forecasting systems in terms of correctly indicating the reported flood events and highlight the exiting limitations of each system. Finally, we propose possible ways forward to improve the reliability of large scale flood monitoring tools.
NASA Astrophysics Data System (ADS)
Sulistyowati, Riny; Sujono, Hari Agus; Musthofa, Ahmad Khamdi
2017-06-01
Due to the high rainfall, flood often occurs in some regions, especially in the area adjacent to the river banks that led to the idea to make the river water level detection system as a flood early warning. Several researches have produced flood detection equipment based on ultrasonic sensors and android as flood early warning system. This paper reported the results of a field test detection equipment to measure the river water level of the Bengawansolo River that was conducted in three villages in the district of Bungah, Dukun, and Manyar in Gresik regency. Tests were conducted simultaneously for 21 hours during heavy rainfall. The test results demonstrated the accuracy of the equipment of 97.28% for all categories of observation. The application of AFD (Android Flood Detection) via android smartphone demonstrated its precision in conveying the information of water level as represented by the status of SAFE, STAND, WARNING, and DANGER. Some charts presented from the analysis of data was derived from the data acquisition time of testing that can be used as an evaluation of flooding at some points prone to flood.
Introduction to SNPP/VIIRS Flood Mapping Software Version 1.0
NASA Astrophysics Data System (ADS)
Li, S.; Sun, D.; Goldberg, M.; Sjoberg, W.; Santek, D.; Hoffman, J.
2017-12-01
Near real-time satellite-derived flood maps are invaluable to river forecasters and decision-makers for disaster monitoring and relief efforts. With support from the JPSS (Joint Polar Satellite System) Proving Ground and Risk Reduction (PGRR) Program, flood detection software has been developed using Suomi-NPP/VIIRS (Suomi National Polar-orbiting Partnership/Visible Infrared Imaging Radiometer Suite) imagery to automatically generate near real-time flood maps for National Weather Service (NWS) River Forecast Centers (RFC) in the USA. The software, which is called VIIRS NOAA GMU Flood Version 1.0 (hereafter referred to as VNG Flood V1.0), consists of a series of algorithms that include water detection, cloud shadow removal, terrain shadow removal, minor flood detection, water fraction retrieval, and floodwater determination. The software is designed for flood detection in any land region between 80°S and 80°N, and it has been running routinely with direct broadcast SNPP/VIIRS data at the Space Science and Engineering Center at the University of Wisconsin-Madison (UW/SSEC) and the Geographic Information Network of Alaska at the University of Alaska-Fairbanks (UAF/GINA) since 2014. Near real-time flood maps are distributed via the Unidata Local Data Manager (LDM), reviewed by river forecasters in AWIPS-II (the second generation of the Advanced Weather Interactive Processing System) and applied in flood operations. Initial feedback from operational forecasters on the product accuracy and performance has been largely positive. The software capability has also been extended to areas outside of the USA via a case-driven mode to detect major floods all over the world. Offline validation efforts include the visual inspection of over 10,000 VIIRS false-color composite images, an inter-comparison with MODIS automatic flood products and a quantitative evaluation using Landsat imagery. The steady performance from the 3-year routine process and the promising validation results indicate that VNG Flood V1.0 has a high feasibility for flood detection at the product level.
NASA Astrophysics Data System (ADS)
Revilla-Romero, Beatriz; Netgeka, Victor; Raynaud, Damien; Thielen, Jutta
2013-04-01
Flood warning systems typically rely on forecasts from national meteorological services and in-situ observations from hydrological gauging stations. This capacity is not equally developed in flood-prone developing countries. Low-cost satellite monitoring systems and global flood forecasting systems can be an alternative source of information for national flood authorities. The Global Flood Awareness System (GloFAS) has been develop jointly with the European Centre for Medium-Range Weather Forecast (ECMWF) and the Joint Research Centre, and it is running quasi operational now since June 2011. The system couples state-of-the art weather forecasts with a hydrological model driven at a continental scale. The system provides downstream countries with information on upstream river conditions as well as continental and global overviews. In its test phase, this global forecast system provides probabilities for large transnational river flooding at the global scale up to 30 days in advance. It has shown its real-life potential for the first time during the flood in Southeast Asia in 2011, and more recently during the floods in Australia in March 2012, India (Assam, September-October 2012) and Chad Floods (August-October 2012).The Joint Research Centre is working on further research and development, rigorous testing and adaptations of the system to create an operational tool for decision makers, including national and regional water authorities, water resource managers, hydropower companies, civil protection and first line responders, and international humanitarian aid organizations. Currently efforts are being made to link GloFAS to the Global Flood Detection System (GFDS). GFDS is a Space-based river gauging and flood monitoring system using passive microwave remote sensing which was developed by a collaboration between the JRC and Dartmouth Flood Observatory. GFDS provides flood alerts based on daily water surface change measurements from space. Alerts are shown on a world map, with detailed reports for individual gauging sites. A comparison of discharge estimates from the Global Flood Detection System (GFDS) and the Global Flood Awareness System (GloFAS) with observations for representative climatic zones is presented. Both systems have demonstrated strong potential in forecasting and detecting recent catastrophic floods. The usefulness of their combined information on global scale for decision makers at different levels is discussed. Combining space-based monitoring and global forecasting models is an innovative approach and has significant benefits for international river commissions as well as international aid organisations. This is in line with the objectives of the Hyogo and the Post-2015 Framework that aim at the development of systems which involve trans-boundary collaboration, space-based earth observation, flood forecasting and early warning.
Global Near Real-Time Satellite-based Flood Monitoring and Product Dissemination
NASA Astrophysics Data System (ADS)
Smith, M.; Slayback, D. A.; Policelli, F.; Brakenridge, G. R.; Tokay, M.
2012-12-01
Flooding is among the most destructive, frequent, and costly natural disasters faced by modern society, with several major events occurring each year. In the past few years, major floods have devastated parts of China, Thailand, Pakistan, Australia, and the Philippines, among others. The toll of these events, in financial costs, displacement of individuals, and deaths, is substantial and continues to rise as climate change generates more extreme weather events. When these events do occur, the disaster management community requires frequently updated and easily accessible information to better understand the extent of flooding and better coordinate response efforts. With funding from NASA's Applied Sciences program, we have developed, and are now operating, a near real-time global flood mapping system to help provide critical flood extent information within 24-48 hours after flooding events. The system applies a water detection algorithm to MODIS imagery received from the LANCE (Land Atmosphere Near real-time Capability for EOS) system at NASA Goddard. The LANCE system typically processes imagery in less than 3 hours after satellite overpass, and our flood mapping system can output flood products within ½ hour of acquiring the LANCE products. Using imagery from both the Terra (10:30 AM local time overpass) and Aqua (1:30 PM) platforms allows an initial assessment of flooding extent by late afternoon, every day, and more robust assessments after accumulating imagery over a longer period; the MODIS sensors are optical, so cloud cover remains an issue, which is partly overcome by using multiple looks over one or more days. Other issues include the relatively coarse scale of the MODIS imagery (250 meters), the difficulty of detecting flood waters in areas with continuous canopy cover, confusion of shadow (cloud or terrain) with water, and accurately identifying detected water as flood as opposed to normal water extents. We have made progress on some of these issues, and are working to develop higher resolution flood detection using alternate sensors, including Landsat and various radar sensors. Although these provide better spatial resolution, this comes at the cost of being less timely. As of late 2011, the system expanded to fully global daily flood monitoring, with free public access to the generated products. These include GIS-ready files of flood and normal water extent (KML, shapefile, raster), and small scale graphic maps (10 degrees square) showing regional flood extent. We are now expanding product distribution channels to include live web services (WMS, etc), allowing easier access via standalone apps. We are also working to bring our product into the Pacific Disaster Center's Disaster Alert system and mobile app for wider accessibility.
A pan-African medium-range ensemble flood forecast system
NASA Astrophysics Data System (ADS)
Thiemig, Vera; Bisselink, Bernard; Pappenberger, Florian; Thielen, Jutta
2015-04-01
The African Flood Forecasting System (AFFS) is a probabilistic flood forecast system for medium- to large-scale African river basins, with lead times of up to 15 days. The key components are the hydrological model LISFLOOD, the African GIS database, the meteorological ensemble predictions of the ECMWF and critical hydrological thresholds. In this study the predictive capability is investigated, to estimate AFFS' potential as an operational flood forecasting system for the whole of Africa. This is done in a hindcast mode, by reproducing pan-African hydrological predictions for the whole year of 2003 where important flood events were observed. Results were analysed in two ways, each with its individual objective. The first part of the analysis is of paramount importance for the assessment of AFFS as a flood forecasting system, as it focuses on the detection and prediction of flood events. Here, results were verified with reports of various flood archives such as Dartmouth Flood Observatory, the Emergency Event Database, the NASA Earth Observatory and Reliefweb. The number of hits, false alerts and missed alerts as well as the Probability of Detection, False Alarm Rate and Critical Success Index were determined for various conditions (different regions, flood durations, average amount of annual precipitations, size of affected areas and mean annual discharge). The second part of the analysis complements the first by giving a basic insight into the prediction skill of the general streamflow. For this, hydrological predictions were compared against observations at 36 key locations across Africa and the Continuous Rank Probability Skill Score (CRPSS), the limit of predictability and reliability were calculated. Results showed that AFFS detected around 70 % of the reported flood events correctly. In particular, the system showed good performance in predicting riverine flood events of long duration (> 1 week) and large affected areas (> 10 000 km2) well in advance, whereas AFFS showed limitations for small-scale and short duration flood events. Also the forecasts showed on average a good reliability, and the CRPSS helped identifying regions to focus on for future improvements. The case study for the flood event in March 2003 in the Sabi Basin (Zimbabwe and Mozambique) illustrated the good performance of AFFS in forecasting timing and severity of the floods, gave an example of the clear and concise output products, and showed that the system is capable of producing flood warnings even in ungauged river basins. Hence, from a technical perspective, AFFS shows a good prospective as an operational system, as it has demonstrated its significant potential to contribute to the reduction of flood-related losses in Africa by providing national and international aid organizations timely with medium-range flood forecast information. However, issues related to the practical implication will still need to be investigated.
Global, Daily, Near Real-Time Satellite-based Flood Monitoring and Product Dissemination
NASA Astrophysics Data System (ADS)
Slayback, D. A.; Policelli, F. S.; Brakenridge, G. R.; Tokay, M. M.; Smith, M. M.; Kettner, A. J.
2013-12-01
Flooding is the most destructive, frequent, and costly natural disaster faced by modern society, and is expected to increase in frequency and damage with climate change and population growth. Some of 2013's major floods have impacted the New York City region, the Midwest, Alberta, Australia, various parts of China, Thailand, Pakistan, and central Europe. The toll of these events, in financial costs, displacement of individuals, and deaths, is substantial and continues to rise as climate change generates more extreme weather events. When these events do occur, the disaster management community requires frequently updated and easily accessible information to better understand the extent of flooding and better coordinate response efforts. With funding from NASA's Applied Sciences program, we developed and are now operating a near real-time global flood mapping system to help provide critical flood extent information within 24-48 hours of events. The system applies a water detection algorithm to MODIS imagery received from the LANCE (Land Atmosphere Near real-time Capability for EOS) system at NASA Goddard within a few hours of satellite overpass. Using imagery from both the Terra (10:30 AM local time overpass) and Aqua (1:30 PM) platforms allows an initial daily assessment of flooding extent by late afternoon, and more robust assessments after accumulating cloud-free imagery over several days. Cloud cover is the primary limitation in detecting surface water from MODIS imagery. Other issues include the relatively coarse scale of the MODIS imagery (250 meters), the difficulty of detecting flood waters in areas with continuous canopy cover, confusion of shadow (cloud or terrain) with water, and accurately identifying detected water as flood as opposed to normal water extents. We have made progress on many of these issues, and are working to develop higher resolution flood detection using alternate sensors, including Landsat and various radar sensors. Although these provide better spatial resolution, this typically comes at the cost of being less timely. Since late 2011, this system has been providing daily flood maps of the global non-antarctic land surface. These data products are generated in raster and vector formats, and provided freely on our website. To better serve the disaster response community, we have recently begun providing the products via live OGC (Open Geospatial Consortium) services, allowing easy access in a variety of platforms (Google Earth, desktop GIS software, mobile phone apps). We are also working with the Pacific Disaster Center to bring our product into their Disaster Alert system (including a mobile app), which will help simplify product distribution to the disaster management community.
Cyber Surveillance for Flood Disasters
Lo, Shi-Wei; Wu, Jyh-Horng; Lin, Fang-Pang; Hsu, Ching-Han
2015-01-01
Regional heavy rainfall is usually caused by the influence of extreme weather conditions. Instant heavy rainfall often results in the flooding of rivers and the neighboring low-lying areas, which is responsible for a large number of casualties and considerable property loss. The existing precipitation forecast systems mostly focus on the analysis and forecast of large-scale areas but do not provide precise instant automatic monitoring and alert feedback for individual river areas and sections. Therefore, in this paper, we propose an easy method to automatically monitor the flood object of a specific area, based on the currently widely used remote cyber surveillance systems and image processing methods, in order to obtain instant flooding and waterlogging event feedback. The intrusion detection mode of these surveillance systems is used in this study, wherein a flood is considered a possible invasion object. Through the detection and verification of flood objects, automatic flood risk-level monitoring of specific individual river segments, as well as the automatic urban inundation detection, has become possible. The proposed method can better meet the practical needs of disaster prevention than the method of large-area forecasting. It also has several other advantages, such as flexibility in location selection, no requirement of a standard water-level ruler, and a relatively large field of view, when compared with the traditional water-level measurements using video screens. The results can offer prompt reference for appropriate disaster warning actions in small areas, making them more accurate and effective. PMID:25621609
Flood trends and river engineering on the Mississippi River system
Pinter, N.; Jemberie, A.A.; Remo, J.W.F.; Heine, R.A.; Ickes, B.S.
2008-01-01
Along >4000 km of the Mississippi River system, we document that climate, land-use change, and river engineering have contributed to statistically significant increases in flooding over the past 100-150 years. Trends were tested using a database of >8 million hydrological measurements. A geospatial database of historical engineering construction was used to quantify the response of flood levels to each unit of engineering infrastructure. Significant climate- and/or land use-driven increases in flow were detected, but the largest and most pervasive contributors to increased flooding on the Mississippi River system were wing dikes and related navigational structures, followed by progressive levee construction. In the area of the 2008 Upper Mississippi flood, for example, about 2 m of the flood crest is linked to navigational and flood-control engineering. Systemwide, large increases in flood levels were documented at locations and at times of wing-dike and levee construction. Copyright 2008 by the American Geophysical Union.
Global Near Real-Time MODIS and Landsat Flood Mapping and Product Delivery
NASA Astrophysics Data System (ADS)
Policelli, F. S.; Slayback, D. A.; Tokay, M. M.; Brakenridge, G. R.
2014-12-01
Flooding is the most destructive, frequent, and costly natural disaster faced by modern society, and is increasing in frequency and damage (deaths, displacements, and financial costs) as populations increase and climate change generates more extreme weather events. When major flooding events occur, the disaster management community needs frequently updated and easily accessible information to better understand the extent of flooding and coordinate response efforts. With funding from NASA's Applied Sciences program, we developed and are now operating a near real-time global flood mapping system to help provide flood extent information within 24-48 hours of events. The principal element of the system applies a water detection algorithm to MODIS imagery, which is processed by the LANCE (Land Atmosphere Near real-time Capability for EOS) system at NASA Goddard within a few hours of satellite overpass. Using imagery from both the Terra (10:30 AM local time overpass) and Aqua (1:30 PM) platforms allows the system to deliver an initial daily assessment of flood extent by late afternoon, and more robust assessments after accumulating cloud-free imagery over several days. Cloud cover is the primary limitation in detecting surface water from MODIS imagery. Other issues include the relatively coarse scale of the MODIS imagery (250 meters) for some events, the difficulty of detecting flood waters in areas with continuous canopy cover, confusion of shadow (cloud or terrain) with water, and accurately identifying detected water as flood as opposed to normal water extent. We are working on improvements to address these limitations. We have also begun delivery of near real time water maps at 30 m resolution from Landsat imagery. Although Landsat is not available daily globally, but only every 8 days if imagery from both operating platforms (Landsat 7 and 8) is accessed, it can provide useful higher resolution data on water extent when a clear acquisition coincides with an active flood event. These data products are provided in various formats on our website, and also via live OGC (Open Geospatial Consortium) services, and ArcGIS Online accessible web maps, allowing easy access from a variety of platforms, from desktop GIS software to web browsers on mobile phones. https://oas.gsfc.nasa.gov/floodmap
Towards a global flood detection system using social media
NASA Astrophysics Data System (ADS)
de Bruijn, Jens; de Moel, Hans; Jongman, Brenden; Aerts, Jeroen
2017-04-01
It is widely recognized that an early warning is critical in improving international disaster response. Analysis of social media in real-time can provide valuable information about an event or help to detect unexpected events. For successful and reliable detection systems that work globally, it is important that sufficient data is available and that the algorithm works both in data-rich and data-poor environments. In this study, both a new geotagging system and multi-level event detection system for flood hazards was developed using Twitter data. Geotagging algorithms that regard one tweet as a single document are well-studied. However, no algorithms exist that combine several sequential tweets mentioning keywords regarding a specific event type. Within the time frame of an event, multiple users use event related keywords that refer to the same place name. This notion allows us to treat several sequential tweets posted in the last 24 hours as one document. For all these tweets, we collect a series of spatial indicators given in the tweet metadata and extract additional topological indicators from the text. Using these indicators, we can reduce ambiguity and thus better estimate what locations are tweeted about. Using these localized tweets, Bayesian change-point analysis is used to find significant increases of tweets mentioning countries, provinces or towns. In data-poor environments detection of events on a country level is possible, while in other, data-rich, environments detection on a city level is achieved. Additionally, on a city-level we analyse the spatial dependence of mentioned places. If multiple places within a limited spatial extent are mentioned, detection confidence increases. We run the algorithm using 2 years of Twitter data with flood related keywords in 13 major languages and validate against a flood event database. We find that the geotagging algorithm yields significantly more data than previously developed algorithms and successfully deals with ambiguous place names. In addition, we show that our detection system can both quickly and reliably detect floods, even in countries where data is scarce, while achieving high detail in countries where more data is available.
Automatic Detection and Vulnerability Analysis of Areas Endangered by Heavy Rain
NASA Astrophysics Data System (ADS)
Krauß, Thomas; Fischer, Peter
2016-08-01
In this paper we present a new method for fully automatic detection and derivation of areas endangered by heavy rainfall based only on digital elevation models. Tracking news show that the majority of occuring natural hazards are flood events. So already many flood prediction systems were developed. But most of these existing systems for deriving areas endangered by flooding events are based only on horizontal and vertical distances to existing rivers and lakes. Typically such systems take not into account dangers arising directly from heavy rain events. In a study conducted by us together with a german insurance company a new approach for detection of areas endangered by heavy rain was proven to give a high correlation of the derived endangered areas and the losses claimed at the insurance company. Here we describe three methods for classification of digital terrain models and analyze their usability for automatic detection and vulnerability analysis for areas endangered by heavy rainfall and analyze the results using the available insurance data.
Whitehead, Matthew T.; Ostheimer, Chad J.
2014-01-01
Flood profiles for selected reaches were prepared by calibrating steady-state step-backwater models to selected streamgage rating curves. The step-backwater models were used to determine water-surface-elevation profiles for up to 12 flood stages at a streamgage with corresponding stream-flows ranging from approximately the 10- to 0.2-percent chance annual-exceedance probabilities for each of the 3 streamgages that correspond to the flood-inundation maps. Additional hydraulic modeling was used to account for the effects of backwater from the Ohio River on water levels in the Muskingum River. The computed longitudinal profiles of flood levels were used with a Geographic Information System digital elevation model (derived from light detection and ranging) to delineate flood-inundation areas. Digital maps showing flood-inundation areas overlain on digital orthophotographs were prepared for the selected floods.
Early Warning System of Flood Disaster Based on Ultrasonic Sensors and Wireless Technology
NASA Astrophysics Data System (ADS)
Indrasari, W.; Iswanto, B. H.; Andayani, M.
2018-04-01
A flood disaster provides considerable losses to the people who live around the river. To mitigate losses of material due to flood disaster required an early warning system of flood disaster. For that reason, it necessary to design a system that provide alert to the people prior the flood disaster. And this paper describes development of a device for early detection system of flood disasters. This device consists of two ultrasonic sensors as a water level detector, and a water flow sensor as a water flow velocity sensor. The wireless technology and GSM is used as an information medium. The system is designed based on water level conditions in the Katulampa Dam, Bogor. Characterization of water level detector showed that the device effectively works in a range of water level of 14-250 cm, with a maximum relative error of 4.3%. Meanwhile the wireless works properly as far as 75 m, and the SMS transmission time is 8.20 second.
NASA Astrophysics Data System (ADS)
Ishitsuka, Y.; Yoshimura, K.
2016-12-01
Floods have a potential to be a major source of economic or human damage caused by natural disasters. Flood prediction systems were developed all over the world and to treat the uncertainty of the prediction ensemble simulation is commonly adopted. In this study, ensemble flood prediction system using global scale land surface and hydrodynamic model was developed. The system requests surface atmospheric forcing and Land Surface Model, MATSIRO, calculates runoff. Those generated runoff is inputted to hydrodynamic model CaMa-Flood to calculate discharge and flood inundation. CaMa-Flood can simulate flood area and its fraction by introducing floodplain connected to river channel. Forecast leadtime was set 39hours according to forcing data. For the case study, the flood occurred at Kinu river basin, Japan in 2015 was hindcasted. In a 1761 km² Kinu river basin, 3-days accumulated average rainfall was 384mm and over 4000 people was left in the inundated area. Available ensemble numerical weather prediction data at that time was inputted to the system in a resolution of 0.05 degrees and 1hour time step. As a result, the system predicted the flood occurrence by 45% and 84% at 23 and 11 hours before the water level exceeded the evacuation threshold, respectively. Those prediction lead time may provide the chance for early preparation for the floods such as levee reinforcement or evacuation. Adding to the discharge, flood area predictability was also analyzed. Although those models were applied for Japan region, this system can be applied easily to other region or even global scale. The areal flood prediction in meso to global scale would be useful for detecting hot zones or vulnerable areas over each region.
NASA Astrophysics Data System (ADS)
Battaglin, W. A.; Bradley, P. M.; Paschke, S.; Plumlee, G. S.; Kimbrough, R.
2016-12-01
In September 2013, heavy rainfall caused severe flooding in Rocky Mountain National Park (ROMO) and environs extending downstream into the main stem of the South Platte River. In ROMO, flooding damaged infrastructure and local roads. In the tributary canyons, flooding damaged homes, septic systems, and roads. On the plains, flooding damaged several wastewater treatment plants. The occurrence and fate of pharmaceuticals and other contaminants of emerging concern (CECs) in streams during flood conditions is poorly understood. We assessed the occurrence and fate of CECs in this flood by collecting water samples (post-peak flow) from 4 headwaters sites in ROMO, 7 sites on tributaries to the South Platte River, and 6 sites on the main stem of the South Platte; and by collecting flood sediment samples (post-flood depositional) from 14 sites on tributaries and 10 sites on the main stem. Water samples were analysed for 110 pharmaceuticals and 69 wastewater indicators. Sediment samples were analysed for 57 wastewater indicators. Concentrations and numbers of CECs detected in water increased markedly as floodwaters moved downstream and some were not diluted despite the large flow increases in downstream reaches of the affected rivers. For example, in the Cache la Poudre River in ROMO, no pharmaceuticals and 1 wastewater indicator compound (camphor) were detected. At Greeley, the Cache la Poudre was transporting 19 pharmaceuticals [total concentration of 0.69 parts-per-billion (ppb)] and 22 wastewater indicators (total concentration of 2.81 ppb). In the South Platte downstream from Greeley, 24 pharmaceuticals (total concentration of 1.47 ppb) and 24 wastewater indicators (total concentration of 2.35 ppb) were detected. Some CECs such as the combustion products pyrene, fluoranthene, and benzo(a)pyrene were detected only at sub-ppb concentrations in water, but were detected at concentrations in the hundreds of ppb in flood sediment samples.
Mapping the Recent US Hurricanes Triggered Flood Events in Near Real Time
NASA Astrophysics Data System (ADS)
Shen, X.; Lazin, R.; Anagnostou, E. N.; Wanik, D. W.; Brakenridge, G. R.
2017-12-01
Synthetic Aperture Radar (SAR) observations is the only reliable remote sensing data source to map flood inundation during severe weather events. Unfortunately, since state-of-art data processing algorithms cannot meet the automation and quality standard of a near-real-time (NRT) system, quality controlled inundation mapping by SAR currently depends heavily on manual processing, which limits our capability to quickly issue flood inundation maps at global scale. Specifically, most SAR-based inundation mapping algorithms are not fully automated, while those that are automated exhibit severe over- and/or under-detection errors that limit their potential. These detection errors are primarily caused by the strong overlap among the SAR backscattering probability density functions (PDF) of different land cover types. In this study, we tested a newly developed NRT SAR-based inundation mapping system, named Radar Produced Inundation Diary (RAPID), using Sentinel-1 dual polarized SAR data over recent flood events caused by Hurricanes Harvey, Irma, and Maria (2017). The system consists of 1) self-optimized multi-threshold classification, 2) over-detection removal using land-cover information and change detection, 3) under-detection compensation, and 4) machine-learning based correction. Algorithm details are introduced in another poster, H53J-1603. Good agreements were obtained by comparing the result from RAPID with visual interpretation of SAR images and manual processing from Dartmouth Flood Observatory (DFO) (See Figure 1). Specifically, the over- and under-detections that is typically noted in automated methods is significantly reduced to negligible levels. This performance indicates that RAPID can address the automation and accuracy issues of current state-of-art algorithms and has the potential to apply operationally on a number of satellite SAR missions, such as SWOT, ALOS, Sentinel etc. RAPID data can support many applications such as rapid assessment of damage losses and disaster alleviation/rescue at global scale.
NASA Astrophysics Data System (ADS)
Ip, F.; Dohm, J. M.; Baker, V. R.; Castano, R.; Cichy, B.; Chien, S.; Davies, A.; Doggett, T.; Greeley, R.
2004-12-01
For the first time, a spacecraft has the ability to autonomously detect and react to flood events. Flood detection and the investigation of flooding dynamics in real time from space have never been done before at least not until now. Part of the challenge for the hydrological community has been the difficulty of obtaining cloud-free scenes from orbit at sufficient temporal and spatial resolutions to accurately assess flooding. In addition, the large spatial extent of drainage networks coupled with the size of the data sets necessary to be downlinked from satellites add to the difficulty of monitoring flooding from space. Technology developed as part of the Autonomous Sciencecraft Experiment (ASE) creates the new capability to autonomously detect, assess, and react to dynamic events, thereby enabling the monitoring of transient processes such as flooding in real time. In addition to being able to autonomously process the imaged data onboard the spacecraft for the first time and search the data for specific spectral features, the ASE Science Team has developed and tested change detection algorithms for the Hyperion spectrometer on EO-1. For flood events, if a change is detected in the onboard processed image (i.e. an increase in the number of ¡wet¡" pixels relative to a baseline image where the system is in normal flow condition or relatively dry), the spacecraft is autonomously retasked to obtain additional scenes. For instance, in February 2004 a rare flooding of the Australian Diamantina River was captured by EO-1. In addition, in August during ASE onboard testing a Zambezi River scene in Central Africa was successfully triggered by the classifier to autonomously take another observation. Yet another successful trigger-response flooding test scenario of the Yellow River in China was captured by ASE on 8/18/04. These exciting results pave the way for future smart reconnaissance missions of transient processes on Earth and beyond. Acknowledgments: We are grateful to the City of Tucson and Tucson Water for their support and cooperation.
NASA Astrophysics Data System (ADS)
Matti, B.; Dahlke, H. E.; Dieppois, B.; Lawler, D.; Lyon, S. W.
2016-12-01
Fluvial flood events have a large impact on humans, both socially and economically. Concurrent with climate change flood seasonality in cold environments is expected to shift from a snowmelt-dominated to a rainfall-dominated flow regime. This would have profound impacts on water management strategies, i.e. flood risk mitigation, drinking water supply and hydro power. In addition, cold climate hydrological systems exhibit complex interactions with catchment properties and large-scale climate fluctuations making the manifestation of changes difficult to detect and predict. Understanding a possible change in flood seasonality is essential to mitigate risk and to keep management strategies viable under a changing climate. This study explored changes in flood seasonality across near-natural catchments in cold environments of the North Atlantic region (40 - 70° N) using circular statistics and trend tests. Results indicate strong seasonality in flooding for snowmelt-dominated catchments with a single peak occurring in spring (March through May), whereas flood peaks are more equally distributed throughout the year for catchments located close to the Atlantic coast and in the south of the study area. Flood seasonality has changed over the past century seen as decreasing trends in summer maximum daily flows and increasing winter and spring maximum daily flows. Mean daily flows corroborate those findings with approximately 50% of the catchments showing significant changes. Comparing Scandinavia to North America the same trends could be detected with a stronger signal at the west coast of Scandinavia due to the Westerlies. Contrasting trends were detected for spring flows, for which North American catchments showed decreasing trends whereas increasing trends were observed across Scandinavia. Such changes in flood seasonality have clear implications for management strategies such as the estimation of design floods for flood prevention measures.
NASA Astrophysics Data System (ADS)
Arcorace, Mauro; Silvestro, Francesco; Rudari, Roberto; Boni, Giorgio; Dell'Oro, Luca; Bjorgo, Einar
2016-04-01
Most flood prone areas in the globe are mainly located in developing countries where making communities more flood resilient is a priority. Despite different flood forecasting initiatives are now available from academia and research centers, what is often missing is the connection between the timely hazard detection and the community response to warnings. In order to bridge the gap between science and decision makers, UN agencies play a key role on the dissemination of information in the field and on capacity-building to local governments. In this context, having a reliable global early warning system in the UN would concretely improve existing in house capacities for Humanitarian Response and the Disaster Risk Reduction. For those reasons, UNITAR-UNOSAT has developed together with USGS and CIMA Foundation a Global Flood EWS called "Flood-FINDER". The Flood-FINDER system is a modelling chain which includes meteorological, hydrological and hydraulic models that are accurately linked to enable the production of warnings and forecast inundation scenarios up to three weeks in advance. The system is forced with global satellite derived precipitation products and Numerical Weather Prediction outputs. The modelling chain is based on the "Continuum" hydrological model and risk assessments produced for GAR2015. In combination with existing hydraulically reconditioned SRTM data and 1D hydraulic models, flood scenarios are derived at multiple scales and resolutions. Climate and flood data are shared through a Web GIS integrated platform. First validation of the modelling chain has been conducted through a flood hindcasting test case, over the Chao Phraya river basin in Thailand, using multi temporal satellite-based analysis derived for the exceptional flood event of 2011. In terms of humanitarian relief operations, the EO-based services of flood mapping in rush mode generally suffer from delays caused by the time required for their activation, programming, acquisitions and image processing. Flood-FINDER aims to pre-empt this process and to provide preliminary analyses where no field data is available. In the early 2015, the Flood-FINDER's forecast along the Shire River has been used to guide the rapid mapping activities in Southern Malawi and Northern Mozambique. It proved efficient support providing timely information about the evolution of the flood event over an area lacking of field data. Regarding in-country capacity building, Flood-FINDER allowed UNOSAT to set up in middle 2015 a flood early warning system in Chad along the Chari River basin with the collaboration of Chadian Ministry of hydraulics and livestock. Weekly flood bulletins have been shared with local authorities and UN agencies over the entire rainy season. Finally, an experimental version of the global web alerting platform has been recently developed for supporting the El Nino flood preparedness in the Horn of Africa. Flood-FINDEŔs mission is to support decision makers throughout all the disaster management cycle with flood alerts, modelled scenarios, EO-based impact assessments and with direct support at country level to implement disaster mitigation strategies. The aim for the future is to seek funding for having the global system fully operational using CERN's supercomputing facilities and to establish new in-country projects with local authorities.
Flood extent and water level estimation from SAR using data-model integration
NASA Astrophysics Data System (ADS)
Ajadi, O. A.; Meyer, F. J.
2017-12-01
Synthetic Aperture Radar (SAR) images have long been recognized as a valuable data source for flood mapping. Compared to other sources, SAR's weather and illumination independence and large area coverage at high spatial resolution supports reliable, frequent, and detailed observations of developing flood events. Accordingly, SAR has the potential to greatly aid in the near real-time monitoring of natural hazards, such as flood detection, if combined with automated image processing. This research works towards increasing the reliability and temporal sampling of SAR-derived flood hazard information by integrating information from multiple SAR sensors and SAR modalities (images and Interferometric SAR (InSAR) coherence) and by combining SAR-derived change detection information with hydrologic and hydraulic flood forecast models. First, the combination of multi-temporal SAR intensity images and coherence information for generating flood extent maps is introduced. The application of least-squares estimation integrates flood information from multiple SAR sensors, thus increasing the temporal sampling. SAR-based flood extent information will be combined with a Digital Elevation Model (DEM) to reduce false alarms and to estimate water depth and flood volume. The SAR-based flood extent map is assimilated into the Hydrologic Engineering Center River Analysis System (Hec-RAS) model to aid in hydraulic model calibration. The developed technology is improving the accuracy of flood information by exploiting information from data and models. It also provides enhanced flood information to decision-makers supporting the response to flood extent and improving emergency relief efforts.
Socio-economic Impact Analysis for Near Real-Time Flood Detection in the Lower Mekong River Basin
NASA Astrophysics Data System (ADS)
Oddo, P.; Ahamed, A.; Bolten, J. D.
2017-12-01
Flood events pose a severe threat to communities in the Lower Mekong River Basin. The combination of population growth, urbanization, and economic development exacerbate the impacts of these flood events. Flood damage assessments are frequently used to quantify the economic losses in the wake of storms. These assessments are critical for understanding the effects of flooding on the local population, and for informing decision-makers about future risks. Remote sensing systems provide a valuable tool for monitoring flood conditions and assessing their severity more rapidly than traditional post-event evaluations. The frequency and severity of extreme flood events are projected to increase, further illustrating the need for improved flood monitoring and impact analysis. In this study we implement a socio-economic damage model into a decision support tool with near real-time flood detection capabilities (NASA's Project Mekong). Surface water extent for current and historical floods is found using multispectral Moderate-resolution Imaging Spectroradiometer (MODIS) 250-meter imagery and the spectral Normalized Difference Vegetation Index (NDVI) signatures of permanent water bodies (MOD44W). Direct and indirect damages to populations, infrastructure, and agriculture are assessed using the 2011 Southeast Asian flood as a case study. Improved land cover and flood depth assessments result in a more refined understanding of losses throughout the Mekong River Basin. Results suggest that rapid initial estimates of flood impacts can provide valuable information to governments, international agencies, and disaster responders in the wake of extreme flood events.
Flood Mapping in the Lower Mekong River Basin Using Daily MODIS Observations
NASA Technical Reports Server (NTRS)
Fayne, Jessica V.; Bolten, John D.; Doyle, Colin S.; Fuhrmann, Sven; Rice, Matthew T.; Houser, Paul R.; Lakshmi, Venkat
2017-01-01
In flat homogenous terrain such as in Cambodia and Vietnam, the monsoon season brings significant and consistent flooding between May and November. To monitor flooding in the Lower Mekong region, the near real-time NASA Flood Extent Product (NASA-FEP) was developed using seasonal normalized difference vegetation index (NDVI) differences from the 250 m resolution Moderate Resolution Imaging Spectroradiometer (MODIS) sensor compared to daily observations. The use of a percentage change interval classification relating to various stages of flooding reduces might be confusing to viewers or potential users, and therefore reducing the product usage. To increase the product usability through simplification, the classification intervals were compared with other commonly used change detection schemes to identify the change classification scheme that best delineates flooded areas. The percentage change method used in the NASA-FEP proved to be helpful in delineating flood boundaries compared to other change detection methods. The results of the accuracy assessments indicate that the -75% NDVI change interval can be reclassified to a descriptive 'flood' classification. A binary system was used to simplify the interpretation of the NASA-FEP by removing extraneous information from lower interval change classes.
On the potential of RST approach for a continuous monitoring of flooded areas
NASA Astrophysics Data System (ADS)
Faruolo, Mariapia; Coviello, Irina; Lacava, Teodosio; Pergola, Nicola; Tramutoli, Valerio
2010-05-01
In recent decades many efforts have been made in the field of remote sensing for the management of flood risk. In fact, among all natural disasters floods are probably the most frequent, causing high human suffering and large losses. All activities designed to mitigate and manage flood risk, in order to be effective and to help civil protection agencies in limiting losses of life, human suffering and damages, need of timely information about the onset of floods, their extent, intensity and duration. At present, sensors aboard meteorological satellites, mainly thanks to their high temporal resolution, may furnish frequent and updated images, ensuring a continuous monitoring of areas involved by a flood. In particular, optical instruments on board polar satellites, like NOAA-AVHRR (National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer) and more recently EOS-MODIS (Earth Observing System-Moderate Resolution Imaging Spectroradiometer) have been used for dynamic flood monitoring. A robust methodology for satellite based flood monitoring and detection, named RST (Robust Satellite Technique), has been recently developed and implemented using data acquired by AVHRR and MODIS to identify flooded areas with reliability and timeliness. Such an approach, based on a multi-temporal analysis of co-located satellite records and an automatic change detection scheme, has been used to analyze floods occurred in different geographic areas and observational conditions. In detail, in order to identify flooded areas within the region of interest, the spectral behavior of water in the visible (VIS) and near infrared (NIR) bands of such satellite systems has been successfully exploited. Starting from these satisfactory results, the main purpose of this paper is to show, in the case of several flooding events occurred recently in different parts of the world, the achievements arising from the use of such methodology also to data acquired in the thermal infrared (TIR) region in order to guarantee a continuous monitoring of flooded areas both during night and day.
Kimbrow, D.R.
2014-01-01
Topographic data at selected areas within the Alabama River flood plain near Montgomery, Alabama, were collected using a truck-mounted mobile terrestrial light detection and ranging system. These data were collected for inclusion in a flood inundation model developed by the National Weather Service in Birmingham, Alabama. Data are presented as ArcGIS point shapefiles with the extension .shp.
Comparison of floods non-stationarity detection methods: an Austrian case study
NASA Astrophysics Data System (ADS)
Salinas, Jose Luis; Viglione, Alberto; Blöschl, Günter
2016-04-01
Non-stationarities in flood regimes have a huge impact in any mid and long term flood management strategy. In particular the estimation of design floods is very sensitive to any kind of flood non-stationarity, as they should be linked to a return period, concept that can be ill defined in a non-stationary context. Therefore it is crucial when analyzing existent flood time series to detect and, where possible, attribute flood non-stationarities to changing hydroclimatic and land-use processes. This works presents the preliminary results of applying different non-stationarity detection methods on annual peak discharges time series over more than 400 gauging stations in Austria. The kind of non-stationarities analyzed include trends (linear and non-linear), breakpoints, clustering beyond stochastic randomness, and detection of flood rich/flood poor periods. Austria presents a large variety of landscapes, elevations and climates that allow us to interpret the spatial patterns obtained with the non-stationarity detection methods in terms of the dominant flood generation mechanisms.
A MODIS-based automated flood monitoring system for southeast asia
NASA Astrophysics Data System (ADS)
Ahamed, A.; Bolten, J. D.
2017-09-01
Flood disasters in Southeast Asia result in significant loss of life and economic damage. Remote sensing information systems designed to spatially and temporally monitor floods can help governments and international agencies formulate effective disaster response strategies during a flood and ultimately alleviate impacts to population, infrastructure, and agriculture. Recent destructive flood events in the Lower Mekong River Basin occurred in 2000, 2011, 2013, and 2016 (http://ffw.mrcmekong.org/historical_rec.htm, April 24, 2017). The large spatial distribution of flooded areas and lack of proper gauge data in the region makes accurate monitoring and assessment of impacts of floods difficult. Here, we discuss the utility of applying satellite-based Earth observations for improving flood inundation monitoring over the flood-prone Lower Mekong River Basin. We present a methodology for determining near real-time surface water extent associated with current and historic flood events by training surface water classifiers from 8-day, 250-m Moderate-resolution Imaging Spectroradiometer (MODIS) data spanning the length of the MODIS satellite record. The Normalized Difference Vegetation Index (NDVI) signature of permanent water bodies (MOD44W; Carroll et al., 2009) is used to train surface water classifiers which are applied to a time period of interest. From this, an operational nowcast flood detection component is produced using twice daily imagery acquired at 3-h latency which performs image compositing routines to minimize cloud cover. Case studies and accuracy assessments against radar-based observations for historic flood events are presented. The customizable system has been transferred to regional organizations and near real-time derived surface water products are made available through a web interface platform. Results highlight the potential of near real-time observation and impact assessment systems to serve as effective decision support tools for governments, international agencies, and disaster responders.
Flood Monitoring and Early Warning System Using Ultrasonic Sensor
NASA Astrophysics Data System (ADS)
Natividad, J. G.; Mendez, J. M.
2018-03-01
The purpose of this study is to develop a real-time flood monitoring and early warning system in the northern portion of the province of Isabela, particularly the municipalities near Cagayan River. Ultrasonic sensing techniques have become mature and are widely used in the various fields of engineering and basic science. One of advantage of ultrasonic sensing is its outstanding capability to probe inside objective non-destructively because ultrasound can propagate through any kinds of media including solids, liquids and gases. This study focuses only on the water level detection and early warning system (via website and/or SMS) that alerts concern agencies and individuals for a potential flood event. Furthermore, inquiry system is also included in this study to become more interactive wherein individuals in the community could inquire the actual water level and status of the desired area or location affected by flood thru SMS keyword. The study aims in helping citizens to be prepared and knowledgeable whenever there is a flood. The novelty of this work falls under the utilization of the Arduino, ultrasonic sensors, GSM module, web-monitoring and SMS early warning system in helping stakeholders to mitigate casualties related to flood. The paper envisions helping flood-prone areas which are common in the Philippines particularly to the local communities in the province. Indeed, it is relevant and important as per needs for safety and welfare of the community.
Using Multiple Space Assests with In-Situ Measurements to Track Flooding in Thailand
NASA Technical Reports Server (NTRS)
Chien, Steve; Doubleday, Joshua; Mclaren, David; Tran, Daniel; Khunboa, Chatchai; Leelapatra, Watis; Pergamon, Vichain; Tanpipat, Veerachai; Chitradon, Royal; Boonya-aroonnet, Surajate;
2001-01-01
Increasing numbers of space assets can enable coordinated measurements of flooding phenomena to enhance tracking of extreme events. We describe the use of space and ground measurements to target further measurements as part of a flood monitoring system in Thailand. We utilize rapidly delivered MODIS data to detect major areas of flooding and the target the Earth Observing One Advanced Land Imager sensor to acquire higher spatial resolution data. Automatic surface water extent mapping products delivered to interested parties. We are also working to extend our network to include in-situ sensing networks and additional space assets.
NASA Technical Reports Server (NTRS)
Ip, Felipe; Dohm, J. M.; Baker, V. R.; Castano, B.; Chien, S.; Cichy, B.; Davies, A. G.; Doggett, T.; Greeley, R.; Sherwood, R.
2005-01-01
NASA's New Millennium Program (NMP) Autonomous Sciencecraft Experiment (ASE) [1-3] has been successfully demonstrated in Earth-orbit. NASA has identified the development of an autonomously operating spacecraft as a necessity for an expanded program of missions exploring the Solar System. The versatile ASE spacecraft command and control, image formation, and science processing software was uploaded to the Earth Observer 1 (EO-1) spacecraft in early 2004 and has been undergoing onboard testing since May 2004 for the near real-time detection of surface modification related to transient geological and hydrological processes such as volcanism [4], ice formation and retreat [5], and flooding [6]. Space autonomy technology developed as part of ASE creates the new capability to autonomously detect, assess, react to, and monitor dynamic events such as flooding. Part of the challenge has been the difficulty to observe flooding in real time at sufficient temporal resolutions; more importantly, it is the large spatial extent of most drainage networks coupled with the size of the data sets necessary to be downlinked from satellites that make it difficult to monitor flooding from space. Below is a description of the algorithms (referred to as ASE Flood water Classifiers) used in tandem with the Hyperion spectrometer instrument on EO-1 to identify flooding and some of the test results.
Low cost, multiscale and multi-sensor application for flooded area mapping
NASA Astrophysics Data System (ADS)
Giordan, Daniele; Notti, Davide; Villa, Alfredo; Zucca, Francesco; Calò, Fabiana; Pepe, Antonio; Dutto, Furio; Pari, Paolo; Baldo, Marco; Allasia, Paolo
2018-05-01
Flood mapping and estimation of the maximum water depth are essential elements for the first damage evaluation, civil protection intervention planning and detection of areas where remediation is needed. In this work, we present and discuss a methodology for mapping and quantifying flood severity over floodplains. The proposed methodology considers a multiscale and multi-sensor approach using free or low-cost data and sensors. We applied this method to the November 2016 Piedmont (northwestern Italy) flood. We first mapped the flooded areas at the basin scale using free satellite data from low- to medium-high-resolution from both the SAR (Sentinel-1, COSMO-Skymed) and multispectral sensors (MODIS, Sentinel-2). Using very- and ultra-high-resolution images from the low-cost aerial platform and remotely piloted aerial system, we refined the flooded zone and detected the most damaged sector. The presented method considers both urbanised and non-urbanised areas. Nadiral images have several limitations, in particular in urbanised areas, where the use of terrestrial images solved this limitation. Very- and ultra-high-resolution images were processed with structure from motion (SfM) for the realisation of 3-D models. These data, combined with an available digital terrain model, allowed us to obtain maps of the flooded area, maximum high water area and damaged infrastructures.
NASA Technical Reports Server (NTRS)
Hood, Robbie E.; Radley, C.D.; LaFontaine, F.J.
2008-01-01
Inland flooding from tropical cyclones can be a significant factor in storm-related deaths in the United States and other countries. Information collected during NASA tropical cyclone field studies suggest surface water and flooding induced by tropical cyclone precipitation can be detected and therefore monitored using passive microwave airborne radiometers. In particular, the 10.7 GHz frequency of the NASA Advanced Microwave Precipitation Radiometer (AMPR) flown on the NASA ER-2 has demonstrated high resolution detection of anomalous surface water and flooding in numerous situations. This presentation will highlight the analysis of three cases utilizing primarily satellite and airborne radiometer data. Radiometer data from the 1998 Third Convection and Moisture Experiment (CAMEX-3) are utilized to detect surface water during landfalling Hurricane Georges in both the Dominican Republic and Louisiana. A third case is landfalling Tropical Storm Gert in Eastern Mexico during the Tropical Cloud Systems and Processes (TCSP) experiment in 2005. AMPR data are compared to topographic data and vegetation indices to evaluate the significance of the surface water signature visible in the 10.7 GHz information. The results of this study suggest the benefit of an aircraft 10 GHz radiometer to provide real-time observations of surface water conditions as part of a multi-sensor flood monitoring network.
Flood Extent Mapping for Namibia Using Change Detection and Thresholding with SAR
NASA Technical Reports Server (NTRS)
Long, Stephanie; Fatoyinbo, Temilola E.; Policelli, Frederick
2014-01-01
A new method for flood detection change detection and thresholding (CDAT) was used with synthetic aperture radar (SAR) imagery to delineate the extent of flooding for the Chobe floodplain in the Caprivi region of Namibia. This region experiences annual seasonal flooding and has seen a recent renewal of severe flooding after a long dry period in the 1990s. Flooding in this area has caused loss of life and livelihoods for the surrounding communities and has caught the attention of disaster relief agencies. There is a need for flood extent mapping techniques that can be used to process images quickly, providing near real-time flooding information to relief agencies. ENVISAT/ASAR and Radarsat-2 images were acquired for several flooding seasons from February 2008 to March 2013. The CDAT method was used to determine flooding from these images and includes the use of image subtraction, decision based classification with threshold values, and segmentation of SAR images. The total extent of flooding determined for 2009, 2011 and 2012 was about 542 km2, 720 km2, and 673 km2 respectively. Pixels determined to be flooded in vegetation were typically <0.5 % of the entire scene, with the exception of 2009 where the detection of flooding in vegetation was much greater (almost one third of the total flooded area). The time to maximum flooding for the 2013 flood season was determined to be about 27 days. Landsat water classification was used to compare the results from the new CDAT with SAR method; the results show good spatial agreement with Landsat scenes.
Delineating Floodplain in North Korea using Remote Sensing and Geographic Information System
NASA Astrophysics Data System (ADS)
Lim, J.; Lee, K. S.
2015-12-01
Korea has been divided into two countries after World War II. So environmental studies about North Korean are not easy and very limited. There were several flood damages every summer in North Korea since 1995, which induces lots of economic loss and agricultural production decrease. Delineating floodplain is indispensable to estimate the magnitude of flood damage and restore the flooded paddy field after unification. Remote Sensing (RS) can provide opportunity to study inaccessible area. In addition, flooding detection is possible. Several research groups study about flooding disaster using RS. Optical images and microwave images have been used in that field. Also, Digital topographic data have been used for flooding detection. Therefore, the purpose of this study is to investigate the land characteristics of floodplain by delineating floodplain in inaccessible North Korea using Landsat and digital topographic data. Landsat TM 5 images were used in this study. North Korea had severe flooding disaster since 1995. Among them 1995, 2007 and 2012 flooding are known for serious damages. Two Landsat images before and after flooding of each year were used to delineate floodplain. Study areas are Pyongyang City, Nampo City, North and South Hwanghae Province and South Pyongan Province. Floodplain are derived from overlaid classification image and flood-depth map. 1:25,000 scale digital topographic data were used to make flood-depth map. For land cover classification image enhancement and supervised classification with maximum likelihood classifier were used. Training areas were selected by visual interpretation using Daum-map which provides high resolution image of whole North Korea. The spatial characteristics of the floodplain were discussed based on floodplain map delineated in this study.
Mahmoud, Shereif H; Gan, Thian Yew
2018-04-26
The effects of urbanization and climate change impact to the flood risk of two governorates in Egypt were analyzed. Non-parametric change point and trend detection algorithms were applied to the annual rainfall, rainfall anomaly, and temperature anomaly of both study sites. Next, change points and trends of the annual and monthly surface runoff data generated by the Curve Number method over 1948-2014 were also analyzed to detect the effects of urbanization on the surface runoff. Lastly, a GIS decision support system was developed to delineate flood susceptibility zones for the two governorates. The significant decline in annual rainfall and rainfall anomaly after 1994 at 8.96 and 15.3 mm/decade respectively was likely due to climate change impact, especially significant warming trend since 1976 at 0.16 °C/decade, though that could partly be attributed to rapid urbanization. Since 1970, effects of urbanization to flood risk are clear, because despite a decline in rainfall, the annual surface runoff and runoff anomaly show positive trends of 12.7 and of 14.39 mm/decade, respectively. Eleven flood contributing factors have been identified and used in mapping flood susceptibility zones of both sites. In the El-Beheira governorate, 9.2%, 17.9%, 32.3%, 28.3% and 12.3% of its area are categorized as very high, high, moderate, low and very low susceptibility to flooding, respectively. Similarly, in Alexandria governorate, 15.9%, 33.5%, 41%, 8.8% and 0.8% of its area are categorized as very high, high, moderate, low and very low susceptibility to flooding, respectively. Very high and high susceptible zones are located in the northern, northwestern and northeastern parts of the Beheira governorates, and in the northeastern and northwestern parts of Alexandria. The flood related information obtained in this study will be useful to assist mitigating potential flood damages and future land use planning of both governorates of Egypt. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Scofield, Rod; Vicente, Gilberto; Hodges, Mike
2000-01-01
This Tech Report summarizes years of study and experiences on using GOES Water vapor (6.7 micron and precipitable water) and Special Sensor Microwave Imager (SSM/1) from the Defense Meteorological Satellite Program (DMSP) derived Precipitable Water (PNAI) for detecting environments favorable for convectively produced flash floods. An emphasis is on the moisture. upper air flow, and equivalent potential temperature (Theta(sub e)) patterns that lead to devastating flood events. The 15 minute 6.7 micron water vapor imagery is essential for tracking middle to upper tropospheric disturbances that produce upward vertical motion and initiate flash flood producing systems. Water vapor imagery at 6.7 micron is also used to detect surges of upper level moisture (called tropical water vapor plumes) that have been associated with extremely heavy rainfall. Since the water vapor readily depicts lifting mechanisms and upper level moisture, water vapor imagery is often an excellent source of data for recognizing patterns of heavy precipitation and flash floods. In order to analyze the depth of the moisture, the PW aspects of the troposphere must be measured. The collocation (or nearby location) of high values ofP\\V and instability are antecedent conditions prior to the flash flood or heavy rainfall events. Knowledge of PW magnitudes have been used as thresholds for impending flash flood events, PW trends are essential in flash flood prediction. Conceptual models and water vapor products are used to study some of the characteristics of convective systems that occurred over the United States of America (USA) during the summer of 1997 and the 1997-1998 El Nino. P\\V plumes were associated with most of the \\vest coast heavy precipitation events examined during the winter season of 1997 - 1998, In another study, conducted during the summer season of 1997. results showed that the collocation of water vapor (6.7 micron) and P\\N' plumes possessed higher correlations with predicted rainfall amounts than when PW plumes occurred by themselves (i.e.. without the presence of 6.7 micron water vapor plumes). Satellite Analysis Branch (SAB) meteorologists use the 6.7 micron water and P\\V products for their QPE's (interactive Flash Flood Analyzer (IFFA) and Auto-Estimator precipitation estimates), Outlooks, and heavy precipitation briefings with the Hydrometeorological Prediction Center/National Center for Environmental Prediction.
NASA Astrophysics Data System (ADS)
Teale, N. G.; Quiring, S. M.
2015-12-01
Understanding flash flooding is important in unfiltered watersheds, such as portions of the New York City water supply system (NYCWSS), as water quality is degraded by turbidity associated with flooding. To further understand flash flooding in watersheds of the NYCWSS, synoptic-scale atmospheric conditions most frequently associated with flash flooding between 1987 and 2013 were examined. Flash floods were identified during this time period using USGS 15-minute discharge data at the Esopus Creek near Allaben, NY and Neversink River at Claryville, NY gauges. Overall, 25 flash floods were detected, occurring over 17 separate flash flood days. These flash flood days were compared to the days on which flash flood warnings encompassing the study area was issued by the National Weather Service. The success rate for which the flash flood warnings for Ulster County coincided with flash flood in the study watershed was 0.09, demonstrating the highly localized nature of flash flooding in the Catskill Mountain region. The synoptic-scale atmospheric patterns influencing the study area were characterized by a principal component analysis and k-means clustering of NCEP/NCAR 500 mb geopotential height reanalysis data. This procedure was executed in Spatial Synoptic Typer Tools 4.0. While 17 unique synoptic patterns were identified, only 3 types were strongly associated with flash flooding events. A strong southwesterly flow suggesting advection of moisture from the Atlantic Ocean and Gulf of Mexico is shown in composites of these 3 types. This multiscalar study thereby links flash flooding in the NYCWSS with synoptic-scale atmospheric circulation.Understanding flash flooding is important in unfiltered watersheds, such as portions of the New York City water supply system (NYCWSS), as water quality is degraded by turbidity associated with flooding. To further understand flash flooding in watersheds of the NYCWSS, synoptic-scale atmospheric conditions most frequently associated with flash flooding between 1987 and 2013 were examined. Flash floods were identified during this time period using USGS 15-minute discharge data at the Esopus Creek near Allaben, NY and Neversink River at Claryville, NY gauges. Overall, 25 flash floods were detected, occurring over 17 separate flash flood days. These flash flood days were compared to the days on which flash flood warnings encompassing the study area was issued by the National Weather Service. The success rate for which the flash flood warnings for Ulster County coincided with flash flood in the study watershed was 0.09, demonstrating the highly localized nature of flash flooding in the Catskill Mountain region. The synoptic-scale atmospheric patterns influencing the study area were characterized by a principal component analysis and k-means clustering of NCEP/NCAR 500 mb geopotential height reanalysis data. This procedure was executed in Spatial Synoptic Typer Tools 4.0. While 17 unique synoptic patterns were identified, only 3 types were strongly associated with flash flooding events. A strong southwesterly flow suggesting advection of moisture from the Atlantic Ocean and Gulf of Mexico is shown in composites of these 3 types. This multiscalar study thereby links flash flooding in the NYCWSS with synoptic-scale atmospheric circulation.
Daily High-Resolution Flood Maps of Africa: 1992-present with Near Real Time Updates
NASA Astrophysics Data System (ADS)
Picton, J.; Galantowicz, J. F.; Root, B.
2016-12-01
The ability to characterize past and current flood extents frequently, accurately, and at high resolution is needed for many applications including risk assessment, wetlands monitoring, and emergency management. However, remote sensing methods have not been capable of meeting all of these requirements simultaneously. Cloud cover too often obscures the surface for visual and infrared sensors and observations from radar sensors are too infrequent to create consistent historical databases or monitor evolving events. Lower-resolution (10-50 km) passive microwave sensors, such as SSM/I, AMSR-E, and AMSR2, are sensitive to water cover, acquire useful data during clear and cloudy conditions, have revisit periods of up to twice daily, and provide a continuous record of data from 1992 to the present. What they lack most is the resolution needed to map flood extent. We will present results from a flood mapping system capable of producing high-resolution (90-m) flood extent depictions from lower resolution microwave data. The system uses the strong sensitivity of microwave data to surface water coverage combined with land surface and atmospheric data to derive daily flooded fraction estimates on a sensor-footprint basis. The system downscales flooded fraction to make high-resolution Boolean flood extent depictions that are spatially continuous and consistent with the lower resolution data. The downscaling step is based on a relative floodability (RF) index derived from higher-resolution topographic and hydrological data. We process RF to create a flooded fraction threshold map that relates each 90-m grid point to the surrounding terrain at the microwave scale. We have derived daily, 90-m resolution flood maps for Africa covering 1992-present using SSM/I, AMSR-E, and AMSR2 data and we are now producing new daily maps in near real time. The flood maps are being used by the African Risk Capacity (ARC) Agency to underpin an intergovernmental river flood insurance program in Africa. We will present results showing daily flood extents during major events and discuss: validation of the flood maps against MODIS-derived maps; analyses of minimum detectable flood size; aggregate analyses of flood extent over time; flood map use in ARC's insurance model; and results applying the system to the Americas.
Climatic and anthropogenic controls on Mississippi River floods: a multi-proxy palaeoflood approach
NASA Astrophysics Data System (ADS)
Munoz, S. E.; Therrell, M. D.; Remo, J. W.; Giosan, L.; Donnelly, J. P.
2017-12-01
Over the last century, many of the world's major rivers have been modified for the purposes of flood mitigation, power generation, and commercial navigation. Engineering modifications to the Mississippi River system have altered the river's sediment budget and channel morphology, but the influence of these modifications on flood risk is debated. Detecting and attributing changes in river discharge is challenging because instrumental streamflow records are often too short to evaluate the range of natural hydrological variability prior to the establishment of flood mitigation infrastructure. Here we show that multi-decadal trends of flood risk on the lower Mississippi River are strongly modulated by dynamical modes of climate variability, particularly the El Niño-Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO), but that artificial channelization has greatly amplified flood magnitudes over the last century. Our results, based on a multi-proxy reconstruction of flood frequency and magnitude spanning the last five hundred years that combines sedimentary, tree-ring, and instrumental records, reveal that the magnitude of the 100-year flood has increased by 20% over the period of record, with 75% of this increase attributed to river engineering. We conclude that the interaction of human alterations to the Mississippi River system with dynamical modes of climate variability has elevated the current flood risk to levels that are unprecedented within the last five centuries.
NASA Astrophysics Data System (ADS)
O'Neill, A.
2015-12-01
The Coastal Storm Modeling System (CoSMoS) is a numerical modeling scheme used to predict coastal flooding due to sea level rise and storms influenced by climate change, currently in use in central California and in development for Southern California (Pt. Conception to the Mexican border). Using a framework of circulation, wave, analytical, and Bayesian models at different geographic scales, high-resolution results are translated as relevant hazards projections at the local scale that include flooding, wave heights, coastal erosion, shoreline change, and cliff failures. Ready access to accurate, high-resolution coastal flooding data is critical for further validation and refinement of CoSMoS and improved coastal hazard projections. High-resolution Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) provides an exceptional data source as appropriately-timed flights during extreme tides or storms provide a geographically-extensive method for determining areas of inundation and flooding extent along expanses of complex and varying coastline. Landward flood extents are numerically identified via edge-detection in imagery from single flights, and can also be ascertained via change detection using additional flights and imagery collected during average wave/tide conditions. The extracted flooding positions are compared against CoSMoS results for similar tide, water level, and storm-intensity conditions, allowing for robust testing and validation of CoSMoS and providing essential feedback for supporting regional and local model improvement.
NASA Astrophysics Data System (ADS)
Versini, P.-A.; Gaume, E.; Andrieu, H.
2010-04-01
This paper presents an initial prototype of a distributed hydrological model used to map possible road inundations in a region frequently exposed to severe flash floods: the Gard region (South of France). The prototype has been tested in a pseudo real-time mode on five recent flash flood events for which actual road inundations have been inventoried. The results are promising: close to 100% probability of detection of actual inundations, inundations detected before they were reported by the road management field teams with a false alarm ratios not exceeding 30%. This specific case study differs from the standard applications of rainfall-runoff models to produce flood forecasts, focussed on a single or a limited number of gauged river cross sections. It illustrates that, despite their lack of accuracy, hydro-meteorological forecasts based on rainfall-runoff models, especially distributed models, contain valuable information for flood event management. The possible consequences of landslides, debris flows and local erosion processes, sometimes associated with flash floods, were not considered at this stage of development of the prototype. They are limited in the Gard region but should be taken into account in future developments of the approach to implement it efficiently in other areas more exposed to these phenomena such as the Alpine area.
Climatic control of Mississippi River flood hazard amplified by river engineering
NASA Astrophysics Data System (ADS)
Munoz, Samuel E.; Giosan, Liviu; Therrell, Matthew D.; Remo, Jonathan W. F.; Shen, Zhixiong; Sullivan, Richard M.; Wiman, Charlotte; O’Donnell, Michelle; Donnelly, Jeffrey P.
2018-04-01
Over the past century, many of the world’s major rivers have been modified for the purposes of flood mitigation, power generation and commercial navigation. Engineering modifications to the Mississippi River system have altered the river’s sediment levels and channel morphology, but the influence of these modifications on flood hazard is debated. Detecting and attributing changes in river discharge is challenging because instrumental streamflow records are often too short to evaluate the range of natural hydrological variability before the establishment of flood mitigation infrastructure. Here we show that multi-decadal trends of flood hazard on the lower Mississippi River are strongly modulated by dynamical modes of climate variability, particularly the El Niño–Southern Oscillation and the Atlantic Multidecadal Oscillation, but that the artificial channelization (confinement to a straightened channel) has greatly amplified flood magnitudes over the past century. Our results, based on a multi-proxy reconstruction of flood frequency and magnitude spanning the past 500 years, reveal that the magnitude of the 100-year flood (a flood with a 1 per cent chance of being exceeded in any year) has increased by 20 per cent over those five centuries, with about 75 per cent of this increase attributed to river engineering. We conclude that the interaction of human alterations to the Mississippi River system with dynamical modes of climate variability has elevated the current flood hazard to levels that are unprecedented within the past five centuries.
Climatic control of Mississippi River flood hazard amplified by river engineering.
Munoz, Samuel E; Giosan, Liviu; Therrell, Matthew D; Remo, Jonathan W F; Shen, Zhixiong; Sullivan, Richard M; Wiman, Charlotte; O'Donnell, Michelle; Donnelly, Jeffrey P
2018-04-04
Over the past century, many of the world's major rivers have been modified for the purposes of flood mitigation, power generation and commercial navigation. Engineering modifications to the Mississippi River system have altered the river's sediment levels and channel morphology, but the influence of these modifications on flood hazard is debated. Detecting and attributing changes in river discharge is challenging because instrumental streamflow records are often too short to evaluate the range of natural hydrological variability before the establishment of flood mitigation infrastructure. Here we show that multi-decadal trends of flood hazard on the lower Mississippi River are strongly modulated by dynamical modes of climate variability, particularly the El Niño-Southern Oscillation and the Atlantic Multidecadal Oscillation, but that the artificial channelization (confinement to a straightened channel) has greatly amplified flood magnitudes over the past century. Our results, based on a multi-proxy reconstruction of flood frequency and magnitude spanning the past 500 years, reveal that the magnitude of the 100-year flood (a flood with a 1 per cent chance of being exceeded in any year) has increased by 20 per cent over those five centuries, with about 75 per cent of this increase attributed to river engineering. We conclude that the interaction of human alterations to the Mississippi River system with dynamical modes of climate variability has elevated the current flood hazard to levels that are unprecedented within the past five centuries.
NASA Astrophysics Data System (ADS)
Prasetyo, Y.; Yuwono, B. D.; Ramadhanis, Z.
2018-02-01
The reclamation program carried out in most cities in North Jakarta is directly adjacent to the Jakarta Bay. Beside this program, the density of population and development center in North Jakarta office has increased the need for underground water excessively. As a result of these things, land subsidence in North Jakarta area is relatively high and so intense. The research methodology was developed based on the method of remote sensing and geographic information systems, expected to describe the spatial correlation between the land subsidence and flood phenomenon in North Jakarta. The DInSAR (Differential Interferometric Synthetic Aperture Radar) method with satellite image data Radar (SAR Sentinel 1A) for the years 2015 to 2016 acquisitions was used in this research. It is intended to obtain a pattern of land subsidence in North Jakarta and then combined with flood patterns. For the preparation of flood threat zoning pattern, this research has been modeling in spatial technique based on a weighted parameter of rainfall, elevation, flood zones and land use. In the final result, we have obtained a flood hazard zonation models then do the overlap against DInSAR processing results. As a result of the research, Geo-hazard modelling has a variety results as: 81% of flood threat zones consist of rural area, 12% consists of un-built areas and 7% consists of water areas. Furthermore, the correlation of land subsidence to flood risk zone is divided into three levels of suitability with 74% in high class, 22% in medium class and 4% in low class. For the result of spatial correlation area between land subsidence and flood risk zone are 77% detected in rural area, 17% detected in un-built area and 6% detected in a water area. Whereas the research product is the geo-hazard maps in North Jakarta as the basis of the spatial correlation analysis between the land subsidence and flooding phenomena.double point.
NASA Astrophysics Data System (ADS)
Bartos, M. D.; Kerkez, B.; Noh, S.; Seo, D. J.
2017-12-01
In this study, we develop and evaluate a high resolution urban flash flood monitoring system using a wireless sensor network (WSN), a real-time rainfall-runoff model, and spatially-explicit radar rainfall predictions. Flooding is the leading cause of natural disaster fatalities in the US, with flash flooding in particular responsible for a majority of flooding deaths. While many riverine flood models have been operationalized into early warning systems, there is currently no model that is capable of reliably predicting flash floods in urban areas. Urban flash floods are particularly difficult to model due to a lack of rainfall and runoff data at appropriate scales. To address this problem, we develop a wide-area flood-monitoring wireless sensor network for the Dallas-Fort Worth metroplex, and use this network to characterize rainfall-runoff response over multiple heterogeneous catchments. First, we deploy a network of 22 wireless sensor nodes to collect real-time stream stage measurements over catchments ranging from 2-80 km2 in size. Next, we characterize the rainfall-runoff response of each catchment by combining stream stage data with gage and radar-based precipitation measurements. Finally, we demonstrate the potential for real-time flash flood prediction by joining the derived rainfall-runoff models with real-time radar rainfall predictions. We find that runoff response is highly heterogeneous among catchments, with large variabilities in runoff response detected even among nearby gages. However, when spatially-explicit rainfall fields are included, spatial variability in runoff response is largely captured. This result highlights the importance of increased spatial coverage for flash flood prediction.
Phalkey, Revati; Dash, Shisir R; Mukhopadhyay, Alok; Runge-Ranzinger, Silvia; Marx, Michael
2012-01-01
Early detection of an impending flood and the availability of countermeasures to deal with it can significantly reduce its health impacts. In developing countries like India, public primary health care facilities are frontline organizations that deal with disasters particularly in rural settings. For developing robust counter reacting systems evaluating preparedness capacities within existing systems becomes necessary. The objective of the study is to assess the functional capacity of the primary health care system in Jagatsinghpur district of rural Orissa in India to respond to the devastating flood of September 2008. An onsite survey was conducted in all 29 primary and secondary facilities in five rural blocks (administrative units) of Jagatsinghpur district in Orissa state. A pre-tested structured questionnaire was administered face to face in the facilities. The data was entered, processed and analyzed using STATA(®) 10. Data from our primary survey clearly shows that the healthcare facilities are ill prepared to handle the flood despite being faced by them annually. Basic utilities like electricity backup and essential medical supplies are lacking during floods. Lack of human resources along with missing standard operating procedures; pre-identified communication and incident command systems; effective leadership; and weak financial structures are the main hindering factors in mounting an adequate response to the floods. The 2008 flood challenged the primary curative and preventive health care services in Jagatsinghpur. Simple steps like developing facility specific preparedness plans which detail out standard operating procedures during floods and identify clear lines of command will go a long way in strengthening the response to future floods. Performance critiques provided by the grass roots workers, like this one, should be used for institutional learning and effective preparedness planning. Additionally each facility should maintain contingency funds for emergency response along with local vendor agreements to ensure stock supplies during floods. The facilities should ensure that baseline public health standards for health care delivery identified by the Government are met in non-flood periods in order to improve the response during floods. Building strong public primary health care systems is a development challenge. The recovery phases of disasters should be seen as an opportunity to expand and improve services and facilities.
Phalkey, Revati; Dash, Shisir R.; Mukhopadhyay, Alok; Runge-Ranzinger, Silvia; Marx, Michael
2012-01-01
Background Early detection of an impending flood and the availability of countermeasures to deal with it can significantly reduce its health impacts. In developing countries like India, public primary health care facilities are frontline organizations that deal with disasters particularly in rural settings. For developing robust counter reacting systems evaluating preparedness capacities within existing systems becomes necessary. Objective The objective of the study is to assess the functional capacity of the primary health care system in Jagatsinghpur district of rural Orissa in India to respond to the devastating flood of September 2008. Methods An onsite survey was conducted in all 29 primary and secondary facilities in five rural blocks (administrative units) of Jagatsinghpur district in Orissa state. A pre-tested structured questionnaire was administered face to face in the facilities. The data was entered, processed and analyzed using STATA® 10. Results Data from our primary survey clearly shows that the healthcare facilities are ill prepared to handle the flood despite being faced by them annually. Basic utilities like electricity backup and essential medical supplies are lacking during floods. Lack of human resources along with missing standard operating procedures; pre-identified communication and incident command systems; effective leadership; and weak financial structures are the main hindering factors in mounting an adequate response to the floods. Conclusion The 2008 flood challenged the primary curative and preventive health care services in Jagatsinghpur. Simple steps like developing facility specific preparedness plans which detail out standard operating procedures during floods and identify clear lines of command will go a long way in strengthening the response to future floods. Performance critiques provided by the grass roots workers, like this one, should be used for institutional learning and effective preparedness planning. Additionally each facility should maintain contingency funds for emergency response along with local vendor agreements to ensure stock supplies during floods. The facilities should ensure that baseline public health standards for health care delivery identified by the Government are met in non-flood periods in order to improve the response during floods. Building strong public primary health care systems is a development challenge. The recovery phases of disasters should be seen as an opportunity to expand and improve services and facilities. PMID:22435044
a Continuous Health Monitoring Guided Wave Fmd System for Retrofit to Existing Offshore Oilrigs
NASA Astrophysics Data System (ADS)
Mijarez, R.; Solis, L.; Martinez, F.
2010-02-01
An automatic health monitoring guided wave flood member detection (FMD) system, for retrofit to existing offshore oilrigs is presented. The system employs a microcontroller piezoelectric (PZT) based transmitter and a receiver instrumentation package composed of a PZT 40 kHz ultrasound transducer and a digital signal processor (DSP) module connected to a PC via USB for monitoring purposes. The transmitter and receiver were attached, non-intrusively, to the external wall of a steel tube; 1 m×27 cm×2 mm. Experiments performed in the laboratory have successfully identified automatically flooded tubes.
Observing floods from space: Experience gained from COSMO-SkyMed observations
NASA Astrophysics Data System (ADS)
Pierdicca, N.; Pulvirenti, L.; Chini, M.; Guerriero, L.; Candela, L.
2013-03-01
The COSMO-SkyMed mission offers a unique opportunity to obtain all weather radar images characterized by short revisit time, thus being useful for flood evolution mapping. The COSMO-SkyMed system has been activated several times in the last few years in occasion of flood events all over the world in order to provide very high resolution X-band SAR images useful for flood detection purposes. This paper discusses the major outcomes of the experience gained, within the framework of the OPERA Pilot Project funded by the Italian Space Agency, from using COSMO-SkyMed data for the purpose of near real time generation of flood maps. A review of the mechanisms which determine the imprints of the inundation on the radar images and of the fundamental simulation tools able to predict these imprints and help image interpretation is provided. The approach developed to process the data and to generate the flood maps is also summarized. Then, the paper illustrates the experience gained with COSMO-SkyMed by describing and discussing a number of significant examples. These examples demonstrate the potential of the COSMO-SkyMed system and the suitability of the approach developed for generating the final products, but they also highlight some critical aspects that require further investigations to improve the reliability of the flood maps.
Non-Native Ambrosia Beetles as Opportunistic Exploiters of Living but Weakened Trees
Ranger, Christopher M.; Schultz, Peter B.; Frank, Steven D.; Chong, Juang H.; Reding, Michael E.
2015-01-01
Exotic Xylosandrus spp. ambrosia beetles established in non-native habitats have been associated with sudden and extensive attacks on a diverse range of living trees, but factors driving their shift from dying/dead hosts to living and healthy ones are not well understood. We sought to characterize the role of host physiological condition on preference and colonization by two invaders, Xylosandrus germanus and Xylosandrus crassiusculus. When given free-choice under field conditions among flooded and non-flooded deciduous tree species of varying intolerance to flooding, beetles attacked flood-intolerant tree species over more tolerant species within 3 days of initiating flood stress. In particular, flood-intolerant flowering dogwood (Cornus florida) sustained more attacks than flood-tolerant species, including silver maple (Acer saccharinum) and swamp white oak (Quercus bicolor). Ethanol, a key host-derived attractant, was detected at higher concentrations 3 days after initiating flooding within stems of flood intolerant species compared to tolerant and non-flooded species. A positive correlation was also detected between ethanol concentrations in stem tissue and cumulative ambrosia beetle attacks. When adult X. germanus and X. crassiusculus were confined with no-choice to stems of flood-stressed and non-flooded C. florida, more ejected sawdust resulting from tunneling activity was associated with the flood-stressed trees. Furthermore, living foundresses, eggs, larvae, and pupae were only detected within galleries created in stems of flood-stressed trees. Despite a capability to attack diverse tree genera, X. germanus and X. crassiusculus efficiently distinguished among varying host qualities and preferentially targeted trees based on their intolerance of flood stress. Non-flooded trees were not preferred or successfully colonized. This study demonstrates the host-selection strategy exhibited by X. germanus and X. crassiusculus in non-native habitats involves detection of stress-induced ethanol emission and early colonization of living but weakened trees. PMID:26134522
Non-Native Ambrosia Beetles as Opportunistic Exploiters of Living but Weakened Trees.
Ranger, Christopher M; Schultz, Peter B; Frank, Steven D; Chong, Juang H; Reding, Michael E
2015-01-01
Exotic Xylosandrus spp. ambrosia beetles established in non-native habitats have been associated with sudden and extensive attacks on a diverse range of living trees, but factors driving their shift from dying/dead hosts to living and healthy ones are not well understood. We sought to characterize the role of host physiological condition on preference and colonization by two invaders, Xylosandrus germanus and Xylosandrus crassiusculus. When given free-choice under field conditions among flooded and non-flooded deciduous tree species of varying intolerance to flooding, beetles attacked flood-intolerant tree species over more tolerant species within 3 days of initiating flood stress. In particular, flood-intolerant flowering dogwood (Cornus florida) sustained more attacks than flood-tolerant species, including silver maple (Acer saccharinum) and swamp white oak (Quercus bicolor). Ethanol, a key host-derived attractant, was detected at higher concentrations 3 days after initiating flooding within stems of flood intolerant species compared to tolerant and non-flooded species. A positive correlation was also detected between ethanol concentrations in stem tissue and cumulative ambrosia beetle attacks. When adult X. germanus and X. crassiusculus were confined with no-choice to stems of flood-stressed and non-flooded C. florida, more ejected sawdust resulting from tunneling activity was associated with the flood-stressed trees. Furthermore, living foundresses, eggs, larvae, and pupae were only detected within galleries created in stems of flood-stressed trees. Despite a capability to attack diverse tree genera, X. germanus and X. crassiusculus efficiently distinguished among varying host qualities and preferentially targeted trees based on their intolerance of flood stress. Non-flooded trees were not preferred or successfully colonized. This study demonstrates the host-selection strategy exhibited by X. germanus and X. crassiusculus in non-native habitats involves detection of stress-induced ethanol emission and early colonization of living but weakened trees.
Flood Detection/Monitoring Using Adjustable Histogram Equalization Technique
Riaz, Muhammad Mohsin; Ghafoor, Abdul
2014-01-01
Flood monitoring technique using adjustable histogram equalization is proposed. The technique overcomes the limitations (overenhancement, artifacts, and unnatural look) of existing technique by adjusting the contrast of images. The proposed technique takes pre- and postimages and applies different processing steps for generating flood map without user interaction. The resultant flood maps can be used for flood monitoring and detection. Simulation results show that the proposed technique provides better output quality compared to the state of the art existing technique. PMID:24558332
29 CFR 1910.160 - Fixed extinguishing systems, general.
Code of Federal Regulations, 2012 CFR
2012-07-01
... sprinkler systems which are covered by § 1910.159. (2) This section also applies to fixed systems not... flooding systems by means of an approved fire detection device installed and interconnected with a pre... 29 Labor 5 2012-07-01 2012-07-01 false Fixed extinguishing systems, general. 1910.160 Section 1910...
29 CFR 1910.160 - Fixed extinguishing systems, general.
Code of Federal Regulations, 2011 CFR
2011-07-01
... sprinkler systems which are covered by § 1910.159. (2) This section also applies to fixed systems not... flooding systems by means of an approved fire detection device installed and interconnected with a pre... 29 Labor 5 2011-07-01 2011-07-01 false Fixed extinguishing systems, general. 1910.160 Section 1910...
29 CFR 1910.160 - Fixed extinguishing systems, general.
Code of Federal Regulations, 2013 CFR
2013-07-01
... sprinkler systems which are covered by § 1910.159. (2) This section also applies to fixed systems not... flooding systems by means of an approved fire detection device installed and interconnected with a pre... 29 Labor 5 2013-07-01 2013-07-01 false Fixed extinguishing systems, general. 1910.160 Section 1910...
29 CFR 1910.160 - Fixed extinguishing systems, general.
Code of Federal Regulations, 2014 CFR
2014-07-01
... sprinkler systems which are covered by § 1910.159. (2) This section also applies to fixed systems not... flooding systems by means of an approved fire detection device installed and interconnected with a pre... 29 Labor 5 2014-07-01 2014-07-01 false Fixed extinguishing systems, general. 1910.160 Section 1910...
Effects of HIFU induced cavitation on flooded lung parenchyma.
Wolfram, Frank; Dietrich, Georg; Boltze, Carsten; Jenderka, Klaus Vitold; Lesser, Thomas Günther
2017-01-01
High intensity focused ultrasound (HIFU) has gained clinical interest as a non-invasive local tumour therapy in many organs. In addition, it has been shown that lung cancer can be targeted by HIFU using One-Lung Flooding (OLF). OLF generates a gas free saline-lung compound in one lung wing and therefore acoustic access to central lung tumours. It can be assumed that lung parenchyma is exposed to ultrasound intensities in the pre-focal path and in cases of misguiding. If so, cavitation might be induced in the saline fraction of flooded lung and cause tissue damage. Therefore this study was aimed to determine the thresholds of HIFU induced cavitation and tissue erosion in flooded lung. Resected human lung lobes were flooded ex-vivo. HIFU (1,1 MHz) was targeted under sonographic guidance into flooded lung parenchyma. Cavitation events were counted using subharmonic passive cavitation detection (PCD). B-Mode imaging was used to detect cavitation and erosion sonographically. Tissue samples out of the focal zone were analysed histologically. In flooded lung, a PCD and a sonographic cavitation detection threshold of 625 Wcm - 2 ( p r = 4, 3 MPa ) and 3.600 Wcm - 2 ( p r = 8, 3 MPa ) was found. Cavitation in flooded lung appears as blurred hyperechoic focal region, which enhances echogenity with insonation time. Lung parenchyma erosion was detected at intensities above 7.200 Wcm - 2 ( p r = 10, 9 MPa ). Cavitation occurs in flooded lung parenchyma, which can be detected passively and by B-Mode imaging. Focal intensities required for lung tumour ablation are below levels where erosive events occur. Therefore focal cavitation events can be monitored and potential risk from tissue erosion in flooded lung avoided.
The 100-year flood seems to be changing. Can we really tell?
NASA Astrophysics Data System (ADS)
Ceres, R. L., Jr.; Forest, C. E.; Keller, K.
2017-12-01
Widespread flooding from Hurricane Harvey greatly exceeded the Federal Emergency Management Agency's 100-year flood levels. In the US, this flood level is often used as an important line of demarcation where areas above this level are considered safe, while areas below the line are at risk and require additional flood risk mitigation. In the wake of Harvey's damage, the US media has highlighted at least two important questions. First, has the 100-year flood level changed? Second, is the 100-year flood level a good metric for determining flood risk? To address the first question, we use an Observation System Simulation Experiment of storm surge flood levels and find that gradual changes to the 100-year storm surge level may not be reliably detected over the long lifespans expected of major flood risk mitigation strategies. Additionally, we find that common extreme value analysis models lead to biased results and additional uncertainty when incorrect assumptions are used for the underlying statistical model. These incorrect assumptions can lead to examples of negative learning. Addressing the second question, these findings further challenge the validity of using simple return levels such as the 100-year flood as a decision tool for assessing flood risk. These results indicate risk management strategies must account for such uncertainties to build resilient and robust planning tools that stakeholders desperately need.
Identification of flood-rich and flood-poor periods in flood series
NASA Astrophysics Data System (ADS)
Mediero, Luis; Santillán, David; Garrote, Luis
2015-04-01
Recently, a general concern about non-stationarity of flood series has arisen, as changes in catchment response can be driven by several factors, such as climatic and land-use changes. Several studies to detect trends in flood series at either national or trans-national scales have been conducted. Trends are usually detected by the Mann-Kendall test. However, the results of this test depend on the starting and ending year of the series, which can lead to different results in terms of the period considered. The results can be conditioned to flood-poor and flood-rich periods located at the beginning or end of the series. A methodology to identify statistically significant flood-rich and flood-poor periods is developed, based on the comparison between the expected sampling variability of floods when stationarity is assumed and the observed variability of floods in a given series. The methodology is applied to a set of long series of annual maximum floods, peaks over threshold and counts of annual occurrences in peaks over threshold series observed in Spain in the period 1942-2009. Mediero et al. (2014) found a general decreasing trend in flood series in some parts of Spain that could be caused by a flood-rich period observed in 1950-1970, placed at the beginning of the flood series. The results of this study support the findings of Mediero et al. (2014), as a flood-rich period in 1950-1970 was identified in most of the selected sites. References: Mediero, L., Santillán, D., Garrote, L., Granados, A. Detection and attribution of trends in magnitude, frequency and timing of floods in Spain, Journal of Hydrology, 517, 1072-1088, 2014.
Flood-inundation maps for the Wabash River at Terre Haute, Indiana
Lombard, Pamela J.
2013-01-01
Digital flood-inundation maps for a 6.3-mi reach of the Wabash River from 0.1 mi downstream of the Interstate 70 bridge to 1.1 miles upstream of the Route 63 bridge, Terre Haute, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to select water levels (stages) at the USGS streamgage Wabash River at Terre Haute (station number 03341500). Current conditions at the USGS streamgage may be obtained on the Internet from the USGS National Water Information System (http://waterdata.usgs.gov/in/nwis/uv/?site_no=03341500&agency_cd=USGS&p"). In addition, the same data are provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps//). Within this system, the NWS forecasts flood hydrographs for the Wabash River at Terre Haute that may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relation at the Wabash River at the Terre Haute streamgage. The hydraulic model was then used to compute 22 water-surface profiles for flood stages at 1-ft interval referenced to the streamgage datum and ranging from bank-full to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data having a 0.37-ft vertical accuracy and a 1.02-ft horizontal accuracy) to delineate the area flooded at each water level. The availability of these maps along with Internet information regarding the current stage from the USGS streamgage and forecasted stream stages from the NWS can provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post flood recovery efforts.
NASA Astrophysics Data System (ADS)
Akay, A. E.; Gencal, B.; Taş, İ.
2017-11-01
This short paper aims to detect spatiotemporal detection of land use/land cover change within Karacabey Flooded Forest region. Change detection analysis applied to Landsat 5 TM images representing July 2000 and a Landsat 8 OLI representing June 2017. Various image processing tools were implemented using ERDAS 9.2, ArcGIS 10.4.1, and ENVI programs to conduct spatiotemporal change detection over these two images such as band selection, corrections, subset, classification, recoding, accuracy assessment, and change detection analysis. Image classification revealed that there are five significant land use/land cover types, including forest, flooded forest, swamp, water, and other lands (i.e. agriculture, sand, roads, settlement, and open areas). The results indicated that there was increase in flooded forest, water, and other lands, while the cover of forest and swamp decreased.
Flash flood warnings for ungauged basins based on high-resolution precipitation forecasts
NASA Astrophysics Data System (ADS)
Demargne, Julie; Javelle, Pierre; Organde, Didier; de Saint Aubin, Céline; Janet, Bruno
2016-04-01
Early detection of flash floods, which are typically triggered by severe rainfall events, is still challenging due to large meteorological and hydrologic uncertainties at the spatial and temporal scales of interest. Also the rapid rising of waters necessarily limits the lead time of warnings to alert communities and activate effective emergency procedures. To better anticipate such events and mitigate their impacts, the French national service in charge of flood forecasting (SCHAPI) is implementing a national flash flood warning system for small-to-medium (up to 1000 km²) ungauged basins based on a discharge-threshold flood warning method called AIGA (Javelle et al. 2014). The current deterministic AIGA system has been run in real-time in the South of France since 2005 and has been tested in the RHYTMME project (rhytmme.irstea.fr/). It ingests the operational radar-gauge QPE grids from Météo-France to run a simplified hourly distributed hydrologic model at a 1-km² resolution every 15 minutes. This produces real-time peak discharge estimates along the river network, which are subsequently compared to regionalized flood frequency estimates to provide warnings according to the AIGA-estimated return period of the ongoing event. The calibration and regionalization of the hydrologic model has been recently enhanced for implementing the national flash flood warning system for the entire French territory by 2016. To further extend the effective warning lead time, the flash flood warning system is being enhanced to ingest Météo-France's AROME-NWC high-resolution precipitation nowcasts. The AROME-NWC system combines the most recent available observations with forecasts from the nowcasting version of the AROME convection-permitting model (Auger et al. 2015). AROME-NWC pre-operational deterministic precipitation forecasts, produced every hour at a 2.5-km resolution for a 6-hr forecast horizon, were provided for 3 significant rain events in September and November 2014 and ingested as time-lagged ensembles. The time-lagged approach is a practical choice of accounting for the atmospheric forecast uncertainty when no extensive forecast archive is available for statistical modelling. The evaluation on 185 basins in the South of France showed significant improvements in terms of flash flood event detection and effective warning lead-time, compared to warnings from the current AIGA setup (without any future precipitation). Various verification metrics (e.g., Relative Mean Error, Brier Skill Score) show the skill of ensemble precipitation and flow forecasts compared to single-valued persistency benchmarks. Planned enhancements include integrating additional probabilistic NWP products (e.g., AROME precipitation ensembles on longer forecast horizon), accounting for and reducing hydrologic uncertainties from the model parameters and initial conditions via data assimilation, and developing a comprehensive observational and post-event damage database to determine decision-relevant warning thresholds for flood magnitude and probability. Javelle, P., Demargne, J., Defrance, D., Arnaud, P., 2014. Evaluating flash flood warnings at ungauged locations using post-event surveys: a case study with the AIGA warning system. Hydrological Sciences Journal, doi: 10.1080/02626667.2014.923970 Auger, L., Dupont, O., Hagelin, S., Brousseau, P., Brovelli, P., 2015. AROME-NWC: a new nowcasting tool based on an operational mesoscale forecasting system. Quarterly Journal of the Royal Meteorological Society, 141: 1603-1611, doi: 10.1002/qj.2463
NASA Astrophysics Data System (ADS)
Tanguy, Marion; Bernier, Monique; Chokmani, Karem
2015-04-01
When a flood hits an inhabited area, managers and services responsible for public safety need precise, reliable and up to date maps of the areas affected by the flood, in order to quickly roll out and to coordinate the adequate intervention and assistance plans required to limit the human and material damages caused by the disaster. Synthetic aperture radar (SAR) sensors are now considered as one of the most adapted tool for flood detection and mapping in a context of crisis management. Indeed, due to their capacity to acquire data night and day, in almost all meteorological conditions, SAR sensors allow the acquisition of synoptic but detailed views of the areas affected by the flood, even during the active phases of the event. Moreover, new generation sensors such as RADARSAT-2, TerraSAR-X, COSMO-SkyMed, are providing very high resolution images of the disaster (down to 1m ground resolution). Further, critical improvements have been made on the temporal repetitivity of acquisitions and on data availability, through the development of satellite constellations (i.e the four COSMO-Skymed or the Sentinel-1A and 1B satellites) and thanks to the implementation of the International Charter "Space and Major Disasters", which guarantees high priority images acquisition and delivery with 4 to 12 hours. If detection of open water flooded areas is relatively straightforward with SAR imagery, flood detection in built-up areas is often associated with important issues. Indeed, because of the side looking geometry of the SAR sensors, structures such as tall vegetation and structures parallel to the satellite direction of travel may produce shadow and layover effects, leading to important over and under-detections of flooded pixels. Besides, the numerous permanent water-surfaces like radar response areas present in built-up environments, such as parking lots, roads etc., may be mixed up with flooded areas, resulting in substantial inaccuracies in the final flood map. In spite of the many efforts recently done toward the improvements of the accuracy of the processing algorithms for flood detection in urban areas with high resolution SAR imagery, these algorithms still encounter difficulties to detect urban flooded pixels with precision. The difficulties do not seem to be only ascribable to the choice of SAR image processing methods, but can also be imputed to the limitations of the SAR imaging technique itself in urban areas. We propose a fully automatic and effective approach for near-real time delineation of urban and rural flooded areas, which combines the capacity of SAR imagery to detect open water areas, and explicit hydrodynamic characteristics of the region affected by the flood, expressed through flood recurrence interval data. This innovative approach has been tested with RADARSAT-2 Fine and Ultrafine Mode images acquired during the 2011 Richelieu River flooding, in Canada. It proved successful in accurately delineating flooding in urban and rural areas, with a RMSE inferior to 2 pixels.
Sieczko, Anna; Peduzzi, Peter
2014-01-01
Spectroscopic techniques and extracellular enzyme activity measurements were combined with assessments of bacterial secondary production (BSP) to elucidate flood-pulse-linked differences in carbon (C) sources and related microbial processes in a river-floodplain system near Vienna (Austria). Surface connection with the main channel significantly influenced the quantity and quality of dissolved organic matter (DOM) in floodplain backwaters. The highest values of dissolved organic carbon (DOC) and chromophoric DOM (CDOM) were observed during the peak of the flood, when DOC increased from 1.36 to 4.37 mg l -1 and CDOM from 2.94 to 14.32 m -1 . The flood introduced DOC which consisted of more allochthonously-derived, aromatic compounds. Bacterial enzymatic activity, as a proxy to track the response to changes in DOM, indicated elevated utilization of imported allochthonous material. Based on the enzyme measurements, new parameters were calculated: metabolic effort and enzymatic indices (EEA 1 and EEA 2). During connection, bacterial glucosidase and protease activity were dominant, whereas during disconnected phases a switch to lignin degradation (phenol oxidase) occurred. The enzymatic activity analysis revealed that flooding mobilized reactive DOM, which then supported bacterial metabolism. No significant differences in overall BSP between the two phases were detected, indicating that heterogeneous sources of C sufficiently support BSP. The study demonstrates that floods are important for delivering DOM, which, despite its allochthonous origin, is reactive and can be effectively utilized by aquatic bacteria in this river-floodplain systems. The presence of active floodplains, characterized by hydrological connectivity with the main channel, creates the opportunity to process allochthonous DOC. This has potential consequences for carbon flux, enhancing C sequestration and mineralization processes in this river-floodplain system.
Kozak, Lidia; Skolasińska, Katarzyna; Niedzielski, Przemysław
2012-09-01
The paper presents the application of the hyphenated technique - high-performance liquid chromatography with atomic absorption spectrometry detection with hydride generation (HPLC-HG-AAS) - in the determinations of inorganic forms of arsenic: As(III) and As(V) in the exchangeable fraction of flood deposits. The separation of analytical signals of the determined arsenic forms was obtained using an ion-exchange column in a chromatographic system with the atomic absorption spectrometer as a detector, at the determination limits of 5 ngg(-1) for As(III) and 10 ngg(-1) for As(V). Flood deposits were collected after big flood event in valley of the Warta river which took place in summer 2010. Samples of overbank deposits were taken in Poznań agglomeration and vicinity (NW Poland). The results of determinations of arsenic forms in the exchangeable fraction of flood deposits allowed indication of a hypothetical path of deposits migration transported by a river during flood and environmental threats posed by their deposition by flood. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Yi, J.; Choi, C.
2014-12-01
Rainfall observation and forecasting using remote sensing such as RADAR(Radio Detection and Ranging) and satellite images are widely used to delineate the increased damage by rapid weather changeslike regional storm and flash flood. The flood runoff was calculated by using adaptive neuro-fuzzy inference system, the data driven models and MAPLE(McGill Algorithm for Precipitation Nowcasting by Lagrangian Extrapolation) forecasted precipitation data as the input variables.The result of flood estimation method using neuro-fuzzy technique and RADAR forecasted precipitation data was evaluated by comparing it with the actual data.The Adaptive Neuro Fuzzy method was applied to the Chungju Reservoir basin in Korea. The six rainfall events during the flood seasons in 2010 and 2011 were used for the input data.The reservoir inflow estimation results were comparedaccording to the rainfall data used for training, checking and testing data in the model setup process. The results of the 15 models with the combination of the input variables were compared and analyzed. Using the relatively larger clustering radius and the biggest flood ever happened for training data showed the better flood estimation in this study.The model using the MAPLE forecasted precipitation data showed better result for inflow estimation in the Chungju Reservoir.
Mining IP to Domain Name Interactions to Detect DNS Flood Attacks on Recursive DNS Servers.
Alonso, Roberto; Monroy, Raúl; Trejo, Luis A
2016-08-17
The Domain Name System (DNS) is a critical infrastructure of any network, and, not surprisingly a common target of cybercrime. There are numerous works that analyse higher level DNS traffic to detect anomalies in the DNS or any other network service. By contrast, few efforts have been made to study and protect the recursive DNS level. In this paper, we introduce a novel abstraction of the recursive DNS traffic to detect a flooding attack, a kind of Distributed Denial of Service (DDoS). The crux of our abstraction lies on a simple observation: Recursive DNS queries, from IP addresses to domain names, form social groups; hence, a DDoS attack should result in drastic changes on DNS social structure. We have built an anomaly-based detection mechanism, which, given a time window of DNS usage, makes use of features that attempt to capture the DNS social structure, including a heuristic that estimates group composition. Our detection mechanism has been successfully validated (in a simulated and controlled setting) and with it the suitability of our abstraction to detect flooding attacks. To the best of our knowledge, this is the first time that work is successful in using this abstraction to detect these kinds of attacks at the recursive level. Before concluding the paper, we motivate further research directions considering this new abstraction, so we have designed and tested two additional experiments which exhibit promising results to detect other types of anomalies in recursive DNS servers.
Mining IP to Domain Name Interactions to Detect DNS Flood Attacks on Recursive DNS Servers
Alonso, Roberto; Monroy, Raúl; Trejo, Luis A.
2016-01-01
The Domain Name System (DNS) is a critical infrastructure of any network, and, not surprisingly a common target of cybercrime. There are numerous works that analyse higher level DNS traffic to detect anomalies in the DNS or any other network service. By contrast, few efforts have been made to study and protect the recursive DNS level. In this paper, we introduce a novel abstraction of the recursive DNS traffic to detect a flooding attack, a kind of Distributed Denial of Service (DDoS). The crux of our abstraction lies on a simple observation: Recursive DNS queries, from IP addresses to domain names, form social groups; hence, a DDoS attack should result in drastic changes on DNS social structure. We have built an anomaly-based detection mechanism, which, given a time window of DNS usage, makes use of features that attempt to capture the DNS social structure, including a heuristic that estimates group composition. Our detection mechanism has been successfully validated (in a simulated and controlled setting) and with it the suitability of our abstraction to detect flooding attacks. To the best of our knowledge, this is the first time that work is successful in using this abstraction to detect these kinds of attacks at the recursive level. Before concluding the paper, we motivate further research directions considering this new abstraction, so we have designed and tested two additional experiments which exhibit promising results to detect other types of anomalies in recursive DNS servers. PMID:27548169
Boschetti, Mirco; Nutini, Francesco; Manfron, Giacinto; Brivio, Pietro Alessandro; Nelson, Andrew
2014-01-01
Identifying managed flooding in paddy fields is commonly used in remote sensing to detect rice. Such flooding, followed by rapid vegetation growth, is a reliable indicator to discriminate rice. Spectral indices (SIs) are often used to perform this task. However, little work has been done on determining which spectral combination in the form of Normalised Difference Spectral Indices (NDSIs) is most appropriate for surface water detection or which thresholds are most robust to separate water from other surfaces in operational contexts. To address this, we conducted analyses on satellite and field spectral data from an agronomic experiment as well as on real farming situations with different soil and plant conditions. Firstly, we review and select NDSIs proposed in the literature, including a new combination of visible and shortwave infrared bands. Secondly, we analyse spectroradiometric field data and satellite data to evaluate mixed pixel effects. Thirdly, we analyse MODIS data and Landsat data at four sites in Europe and Asia to assess NDSI performance in real-world conditions. Finally, we test the performance of the NDSIs on MODIS temporal profiles in the four sites. We also compared the NDSIs against a combined index previously used for agronomic flood detection. Analyses suggest that NDSIs using MODIS bands 4 and 7, 1 and 7, 4 and 6 or 1 and 6 perform best. A common threshold for each NDSI across all sites was more appropriate than locally adaptive thresholds. In general, NDSIs that use band 7 have a negligible increase in Commission Error over those that use band 6 but are more sensitive to water presence in mixed land cover conditions typical of moderate spatial resolution analyses. The best performing NDSI is comparable to the combined index but with less variability in performance across sites, suggesting a more succinct and robust flood detection method. PMID:24586381
Real World Experience With Ion Implant Fault Detection at Freescale Semiconductor
NASA Astrophysics Data System (ADS)
Sing, David C.; Breeden, Terry; Fakhreddine, Hassan; Gladwin, Steven; Locke, Jason; McHugh, Jim; Rendon, Michael
2006-11-01
The Freescale automatic fault detection and classification (FDC) system has logged data from over 3.5 million implants in the past two years. The Freescale FDC system is a low cost system which collects summary implant statistics at the conclusion of each implant run. The data is collected by either downloading implant data log files from the implant tool workstation, or by exporting summary implant statistics through the tool's automation interface. Compared to the traditional FDC systems which gather trace data from sensors on the tool as the implant proceeds, the Freescale FDC system cannot prevent scrap when a fault initially occurs, since the data is collected after the implant concludes. However, the system can prevent catastrophic scrap events due to faults which are not detected for days or weeks, leading to the loss of hundreds or thousands of wafers. At the Freescale ATMC facility, the practical applications of the FD system fall into two categories: PM trigger rules which monitor tool signals such as ion gauges and charge control signals, and scrap prevention rules which are designed to detect specific failure modes that have been correlated to yield loss and scrap. PM trigger rules are designed to detect shifts in tool signals which indicate normal aging of tool systems. For example, charging parameters gradually shift as flood gun assemblies age, and when charge control rules start to fail a flood gun PM is performed. Scrap prevention rules are deployed to detect events such as particle bursts and excessive beam noise, events which have been correlated to yield loss. The FDC system does have tool log-down capability, and scrap prevention rules often use this capability to automatically log the tool into a maintenance state while simultaneously paging the sustaining technician for data review and disposition of the affected product.
Olimpio, Joseph R.
2000-01-01
Ground-penetrating radar was used to measure the depth and extent of existing and infilled scour holes and previous scour surfaces at seven bridges in New Hampshire from April 1996 to November 1998. Ground-penetrating-radar survey techniques initially were used by the U.S. Geological Survey to study streambed scour at 30 bridges. Sixteen of the 30 bridges were re-surveyed where floods exceeded a 2-year recurrence interval. A 300-megahertz signal was used in the ground-penetrating radar system that penetrated through depths as great as 20 feet of water and as great as 32 feet of streambed materials. Existing scour-hole dimensions, infilled thickness, previous scour surfaces, and streambed materials were detected using ground-penetrating radar. Depths to riprap materials and pier footings were identified and verified with bridge plans. Post data-collection-processing techniques were applied to assist in the interpretation of the data, and the processed data were displayed and printed as line plots. Processing included distance normalization, migration, and filtering but processing was kept to a minimum and some interference from multiple reflections was left in the record. Of the 16 post-flood bridges, 22 ground-penetrating-radar cross sections at 7 bridges were compared and presented in this report. Existing scour holes were detected during 1996 (pre-flood) data collection in nine cross sections where scour depths ranged from 1 to 3 feet. New scour holes were detected during 1998 (post-flood) data collection in four cross sections where scour depths were as great as 4 feet deep. Infilled scour holes were detected in seven cross sections, where depths of infilling ranged from less than 1 to 4 feet. Depth of infilling by means of steel rod and hammer was difficult to verify in the field because of cobble and boulder streambeds or deep water. Previous scour surfaces in streambed materials were identified in 15 cross sections and the depths to these surfaces ranged from 1 to 10 feet below the streambed. Riprap materials or pier footings were identified in all cross sections. Calculated record depths generally agree with bridge plans. Pier footings were exposed at two bridges and steel pile was exposed at one bridge. Exposures were verified by field observations.
NASA Astrophysics Data System (ADS)
Galantowicz, J. F.; Picton, J.; Root, B.
2017-12-01
Passive microwave remote sensing can provided a distinct perspective on flood events by virtue of wide sensor fields of view, frequent observations from multiple satellites, and sensitivity through clouds and vegetation. During Hurricanes Harvey and Irma, we used AMSR2 (Advanced Microwave Scanning Radiometer 2, JAXA) data to map flood extents starting from the first post-storm rain-free sensor passes. Our standard flood mapping algorithm (FloodScan) derives flooded fraction from 22-km microwave data (AMSR2 or NASA's GMI) in near real time and downscales it to 90-m resolution using a database built from topography, hydrology, and Global Surface Water Explorer data and normalized to microwave data footprint shapes. During Harvey and Irma we tested experimental versions of the algorithm designed to map the maximum post-storm flood extent rapidly and made a variety of map products available immediately for use in storm monitoring and response. The maps have several unique features including spanning the entire storm-affected area and providing multiple post-storm updates as flood water shifted and receded. From the daily maps we derived secondary products such as flood duration, maximum flood extent (Figure 1), and flood depth. In this presentation, we describe flood extent evolution, maximum extent, and local details as detected by the FloodScan algorithm in the wake of Harvey and Irma. We compare FloodScan results to other available flood mapping resources, note observed shortcomings, and describe improvements made in response. We also discuss how best-estimate maps could be updated in near real time by merging FloodScan products and data from other remote sensing systems and hydrological models.
NASA Astrophysics Data System (ADS)
Zhang, Qiang; Gu, Xihui; Singh, Vijay P.; Shi, Peijun; Sun, Peng
2018-05-01
Flood risks across the Pearl River basin, China, were evaluated using a peak flood flow dataset covering a period of 1951-2014 from 78 stations and historical flood records of the past 1000 years. The generalized extreme value (GEV) model and the kernel estimation method were used to evaluate frequencies and risks of hazardous flood events. Results indicated that (1) no abrupt changes or significant trends could be detected in peak flood flow series at most of the stations, and only 16 out of 78 stations exhibited significant peak flood flow changes with change points around 1990. Peak flood flow in the West River basin increased and significant increasing trends were identified during 1981-2010; decreasing peak flood flow was found in coastal regions and significant trends were observed during 1951-2014 and 1966-2014. (2) The largest three flood events were found to cluster in both space and time. Generally, basin-scale flood hazards can be expected in the West and North River basins. (3) The occurrence rate of floods increased in the middle Pearl River basin but decreased in the lower Pearl River basin. However, hazardous flood events were observed in the middle and lower Pearl River basin, and this is particularly true for the past 100 years. However, precipitation extremes were subject to moderate variations and human activities, such as building of levees, channelization of river systems, and rapid urbanization; these were the factors behind the amplification of floods in the middle and lower Pearl River basin, posing serious challenges for developing measures of mitigation of flood hazards in the lower Pearl River basin, particularly the Pearl River Delta (PRD) region.
NASA Astrophysics Data System (ADS)
Shastri, Hiteshri; Ghosh, Subimal; Karmakar, Subhankar
2017-02-01
Forecasting of extreme precipitation events at a regional scale is of high importance due to their severe impacts on society. The impacts are stronger in urban regions due to high flood potential as well high population density leading to high vulnerability. Although significant scientific improvements took place in the global models for weather forecasting, they are still not adequate at a regional scale (e.g., for an urban region) with high false alarms and low detection. There has been a need to improve the weather forecast skill at a local scale with probabilistic outcome. Here we develop a methodology with quantile regression, where the reliably simulated variables from Global Forecast System are used as predictors and different quantiles of rainfall are generated corresponding to that set of predictors. We apply this method to a flood-prone coastal city of India, Mumbai, which has experienced severe floods in recent years. We find significant improvements in the forecast with high detection and skill scores. We apply the methodology to 10 ensemble members of Global Ensemble Forecast System and find a reduction in ensemble uncertainty of precipitation across realizations with respect to that of original precipitation forecasts. We validate our model for the monsoon season of 2006 and 2007, which are independent of the training/calibration data set used in the study. We find promising results and emphasize to implement such data-driven methods for a better probabilistic forecast at an urban scale primarily for an early flood warning.
Engineering Software for Interoperability through Use of Enterprise Architecture Techniques
2003-03-01
Response Home/ Business Security . To detect flood conditions (i.e. excess water levels) within the monitored area and alert authorities, as necessary...Response; Fire Detection & Response; and Flood Detection & Response. Functional Area Description Intruder Detection & Response Home/ Business ... Security . To monitor and detect unauthorized entry into the secured area and sound alarms/alert authorities, as necessary. Fire Detection
Hydrologic ensembles based on convection-permitting precipitation nowcasts for flash flood warnings
NASA Astrophysics Data System (ADS)
Demargne, Julie; Javelle, Pierre; Organde, Didier; de Saint Aubin, Céline; Ramos, Maria-Helena
2017-04-01
In order to better anticipate flash flood events and provide timely warnings to communities at risk, the French national service in charge of flood forecasting (SCHAPI) is implementing a national flash flood warning system for small-to-medium ungauged basins. Based on a discharge-threshold flood warning method called AIGA (Javelle et al. 2014), the current version of the system runs a simplified hourly distributed hydrologic model with operational radar-gauge QPE grids from Météo-France at a 1-km2 resolution every 15 minutes. This produces real-time peak discharge estimates along the river network, which are subsequently compared to regionalized flood frequency estimates to provide warnings according to the AIGA-estimated return period of the ongoing event. To further extend the effective warning lead time while accounting for hydrometeorological uncertainties, the flash flood warning system is being enhanced to include Météo-France's AROME-NWC high-resolution precipitation nowcasts as time-lagged ensembles and multiple sets of hydrological regionalized parameters. The operational deterministic precipitation forecasts, from the nowcasting version of the AROME convection-permitting model (Auger et al. 2015), were provided at a 2.5-km resolution for a 6-hr forecast horizon for 9 significant rain events from September 2014 to June 2016. The time-lagged approach is a practical choice of accounting for the atmospheric forecast uncertainty when no extensive forecast archive is available for statistical modelling. The evaluation on 781 French basins showed significant improvements in terms of flash flood event detection and effective warning lead-time, compared to warnings from the current AIGA setup (without any future precipitation). We also discuss how to effectively communicate verification information to help determine decision-relevant warning thresholds for flood magnitude and probability. Javelle, P., Demargne, J., Defrance, D., Arnaud, P., 2014. Evaluating flash flood warnings at ungauged locations using post-event surveys: a case study with the AIGA warning system. Hydrological Sciences Journal, doi: 10.1080/02626667.2014.923970 Auger, L., Dupont, O., Hagelin, S., Brousseau, P., Brovelli, P., 2015. AROME-NWC: a new nowcasting tool based on an operational mesoscale forecasting system. Quarterly Journal of the Royal Meteorological Society, 141: 1603-1611, doi:10.1002/qj.2463
Safety in the Chemical Laboratory: Flood Control.
ERIC Educational Resources Information Center
Pollard, Bruce D.
1983-01-01
Describes events leading to a flood in the Wehr Chemistry Laboratory at Marquette University, discussing steps taken to minimize damage upon discovery. Analyzes the problem of flooding in the chemical laboratory and outlines seven steps of flood control: prevention; minimization; early detection; stopping the flood; evaluation; clean-up; and…
Cesarz, Simone; Ciobanu, Marcel; Wright, Alexandra J; Ebeling, Anne; Vogel, Anja; Weisser, Wolfgang W; Eisenhauer, Nico
2017-07-01
The magnitude and frequency of extreme weather events are predicted to increase in the future due to ongoing climate change. In particular, floods and droughts resulting from climate change are thought to alter the ecosystem functions and stability. However, knowledge of the effects of these weather events on soil fauna is scarce, although they are key towards functioning of terrestrial ecosystems. Plant species richness has been shown to affect the stability of ecosystem functions and food webs. Here, we used the occurrence of a natural flood in a biodiversity grassland experiment that was followed by a simulated summer drought experiment, to investigate the interactive effects of plant species richness, a natural flood, and a subsequent summer drought on nematode communities. Three and five months after the natural flooding, effects of flooding severity were still detectable in the belowground system. We found that flooding severity decreased soil nematode food-web structure (loss of K-strategists) and the abundance of plant feeding nematodes. However, high plant species richness maintained higher diversity and abundance of higher trophic levels compared to monocultures throughout the flood. The subsequent summer drought seemed to be of lower importance but reversed negative flooding effects in some cases. This probably occurred because the studied grassland system is well adapted to drought, or because drought conditions alleviated the negative impact of long-term soil waterlogging. Using soil nematodes as indicator taxa, this study suggests that high plant species richness can maintain soil food web complexity after consecutive environmental perturbations.
NASA Astrophysics Data System (ADS)
Naulin, J.-P.; Payrastre, O.; Gaume, E.
2013-04-01
SummaryAccurate flood forecasts are critical to an efficient flood event management strategy. Until now, hydro-meteorological forecasts have mainly been used to establish early-warnings in France (meteorological and flood vigilance maps) or over the world (flash-flood guidances). These forecasts are typically limited either to the main streams covered by the flood forecasting services or to watersheds with specific assets like check dams, which in most cases are well gauged river sections, thus leaving aside large parts of the territory. This paper presents a distributed hydro-meteorological forecasting approach, which makes use of the high spatial and temporal resolution rainfall estimates that are now available, to provide information at ungauged sites. The proposed system intended to detect road inundation risks had initially been developed and tested in areas of limited size. This paper presents the extension of such a system to an entire region (i.e. the Gard region in Southern France), including over 2000 crossing points between rivers and roads and its validation with respect to a large data set of actual reported road inundations observed during recent flash flood events. These initial validation results appear to be most promising. The eventual proposed tool would provide the necessary information for flood event management services to identify the areas at risk and adopt appropriate safety and rescue measures: i.e. pre-positioning of rescue equipment, interruption of the traffic on the exposed roads and determination of safe access or evacuation routes. Moreover, beyond the specific application to the supervision of a road network, the research undertaken herein also provides results for the performance of hydro-meteorological forecasts on ungauged headwaters.
Flood-inundation maps for the St. Marys River at Fort Wayne, Indiana
Menke, Chad D.; Kim, Moon H.; Fowler, Kathleen K.
2012-01-01
Digital flood-inundation maps for a 9-mile reach of the St. Marys River that extends from South Anthony Boulevard to Main Street at Fort Wayne, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Fort Wayne. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at the USGS streamgage 04182000 St. Marys River near Fort Wayne, Ind. Current conditions at the USGS streamgages in Indiana may be obtained from the National Water Information System: Web Interface. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system. The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, water-surface profiles were simulated for the stream reach by means of a hydraulic one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relation at the USGS streamgage 04182000 St. Marys River near Fort Wayne, Ind. The hydraulic model was then used to simulate 11 water-surface profiles for flood stages at 1-ft intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. A flood inundation map was generated for each water-surface profile stage (11 maps in all) so that for any given flood stage users will be able to view the estimated area of inundation. The availability of these maps along with current stage from USGS streamgages and forecasted stream stages from the NWS provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post flood recovery efforts.
Flood-inundation maps for the East Fork White River at Columbus, Indiana
Lombard, Pamela J.
2013-01-01
Digital flood-inundation maps for a 5.4-mile reach of the East Fork White River at Columbus, Indiana, from where the Flatrock and Driftwood Rivers combine to make up East Fork White River to just upstream of the confluence of Clifty Creek with the East Fork White River, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at USGS streamgage 03364000, East Fork White River at Columbus, Indiana. Current conditions at the USGS streamgage may be obtained on the Internet from the USGS National Water Information System (http://waterdata.usgs.gov/in/nwis/uv/?site_no=03364000&agency_cd=USGS&). The National Weather Service (NWS) forecasts flood hydrographs for the East Fork White River at Columbus, Indiana at their Advanced Hydrologic Prediction Service (AHPS) flood warning system Website (http://water.weather.gov/ahps/), that may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at USGS streamgage 03364000, East Fork White River at Columbus, Indiana. The calibrated hydraulic model was then used to determine 15 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data), having a 0.37-ft vertical accuracy and a 1.02 ft horizontal accuracy), in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at Columbus, Indiana, and forecasted stream stages from the NWS will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post-flood recovery efforts.
Cooperative satellite-based flood detection, mapping, and river monitoring in near real time
NASA Technical Reports Server (NTRS)
Brakenridge, Robert G.; Nghiem, Son V.
2004-01-01
The North Atlantic Oscillation (NAO), the Pacific-North American (PNA) teleconnection pattern, and the El Nino-Southern Oscillation (ENSO) combine to influence the planetary wave structure over the northern hemisphere. Floods and droughts are associated around the world with ENSO through such teleconnections, and improved flood prediction relies on understanding them better. The scientific study of floods, and consistent measurements thereof, are needed in order to allow 'Greenhouse warming' predictions about flooding to be tested, and the hydrologic effects of other phenomena such as ENSO to be evaluated. The needed tasks are: 1) detection/warning of flooding, 2) flood magnitude assessment, 3) flood inundation mapping, and 4) preservation of the record of flooding. Accomplishing these same tasks provides direct local societal benefits as well: they can save lives and reduce economic loss. We emphasize that the basic science observations need not be divorced from the immediate practical applications: both can occur together, and just as is the case for meteorological remote sensing.
NASA Astrophysics Data System (ADS)
Tong, Xiaohua; Luo, Xin; Liu, Shuguang; Xie, Huan; Chao, Wei; Liu, Shuang; Liu, Shijie; Makhinov, A. N.; Makhinova, A. F.; Jiang, Yuying
2018-02-01
Remote sensing techniques offer potential for effective flood detection with the advantages of low-cost, large-scale, and real-time surface observations. The easily accessible data sources of optical remote sensing imagery provide abundant spectral information for accurate surface water body extraction, and synthetic aperture radar (SAR) systems represent a powerful tool for flood monitoring because of their all-weather capability. This paper introduces a new approach for flood monitoring by the combined use of both Landsat 8 optical imagery and COSMO-SkyMed radar imagery. Specifically, the proposed method applies support vector machine and the active contour without edges model for water extent determination in the periods before and during the flood, respectively. A map difference method is used for the flood inundation analysis. The proposed approach is particularly suitable for large-scale flood monitoring, and it was tested on a serious flood that occurred in northeastern China in August 2013, which caused immense loss of human lives and properties. High overall accuracies of 97.46% for the optical imagery and 93.70% for the radar imagery are achieved by the use of the techniques presented in this study. The results show that about 12% of the whole study area was inundated, corresponding to 5466 km2 of land surface.
Detection of Flood Inundation Information of the Kinu River Flooding in 2015 by Social Media
NASA Astrophysics Data System (ADS)
Shi, Y.; Sayama, T.; Takara, K. T.
2016-12-01
On September 10th, 2015, due to Kanto Tohoku heavy rainfall in Japan, an overtopping occurred from the Kinu River around 6:00. At the same day, levee breach occurred at the downstream area near Joso city in Ibaraki Prefecture, Japan. This flood disaster caused two people dead, several people injured, and enormous damages on houses and infrastructures in the city. In order to mitigate such flood disasters with large inundations, it is important to identify flood-affected areas on real-time basis. The real-time flood hazard map, which is our ultimate goal of the study, provides information on location of inundated areas during a flood. However, the technology has not been achieved yet mainly due to the difficulty in identifying the flood extent on real time. With the advantage of efficiency and wide coverage, social media, such as Twitter, appears as a good data source for collecting real-time flood information. However, there are some concerns on social media information, including the trustworthiness, and the amount of useful information in the case tweets from flood affected areas. This study collected tweet regarding the Kinu River flooding and investigated how many people in affected area posted tweets on the flooding and how the detected information is useful for the eventual goal on the real-time flood hazard mapping. The tweets were collected by three ways: advanced search on twitter web page; DISAster-information ANAlyzer system; and Twitter Application Programming Interfaces. As a result, 109 disaster relevant tweets were collected. Out of the 109 tweets, 32% of the total tweets are posted at real-time, 43% of total tweets are posted with photos and 46 tweets are related to the inundation information. 46% of the inundation related tweets were able to identify locations. In order to investigate the reliability of tweet post, the location identified tweets were marked on map to compare with the real inundation extent that measured by the Geospatial Information Authority of Japan (GSI) by helicopter on September 10, 2015. The result shows a good agreement between the actual inundation information and tweet post. Moreover, the tweet posts show an appropriate change of inundation extent. In addition, tweet posts show some additional inundated areas not reported by GSI, but confirmed the inundation after the disaster.
Magnitude and extent of flooding at selected river reaches in western Washington, January 2009
Mastin, M.C.; Gendaszek, A.S.; Barnas, C.R.
2010-01-01
A narrow plume of warm, moist tropical air produced prolonged precipitation and melted snow in low-to-mid elevations throughout western Washington in January 2009. As a result, peak-of-record discharges occurred at many long-term streamflow-gaging stations in the region. A disaster was declared by the President for eight counties in Washington State and by May 2009, aid payments by the Federal Emergency Management Agency (FEMA) had exceeded $17 million. In an effort to document the flood and to obtain flood information that could be compared with simulated flood extents that are commonly prepared in conjunction with flood insurance studies by FEMA, eight stream reaches totaling 32.6 miles were selected by FEMA for inundation mapping. The U.S. Geological Survey?s Washington Water Science Center used a survey-grade global positioning system (GPS) the following summer to survey high-water marks (HWMs) left by the January 2009 flood at these reaches. A Google Maps (copyright) application was developed to display all HWM data on an interactive mapping tool on the project?s web site soon after the data were collected. Water-surface profiles and maps that display the area and depth of inundation were produced through a geographic information system (GIS) analysis that combined surveyed HWM elevations with Light Detection and Ranging (LiDAR)-derived digital elevation models of the study reaches and surrounding terrain. In several of the reaches, floods were well confined in their flood plains and were relatively straightforward to map. More common, however, were reaches with more complicated hydraulic geometries where widespread flooding resulted in flows that separated from the main channel. These proved to be more difficult to map, required subjective hydrologic judgment, and relied on supplementary information, such as aerial photographs and descriptions of the flooding from local landowners and government officials to obtain the best estimates of the extent of flooding.
Flood-inundation maps for the Big Blue River at Shelbyville, Indiana
Fowler, Kathleen K.
2017-02-13
Digital flood-inundation maps for a 4.1-mile reach of the Big Blue River at Shelbyville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The floodinundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at https://water. usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Big Blue River at Shelbyville, Ind. (station number 03361500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata. usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at https://water.weather.gov/ ahps/, which also forecasts flood hydrographs at this site (SBVI3). Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Big Blue River at Shelbyville, Ind., streamgage. The calibrated hydraulic model was then used to compute 12 water-surface profiles for flood stages referenced to the streamgage datum and ranging from 9.0 feet, or near bankfull, to 19.4 feet, the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging [lidar] data having a 0.98-foot vertical accuracy and 4.9-foot horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at the Big Blue River at Shelbyville, Ind., and forecasted stream stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post-flood recovery efforts.
Flood-inundation maps for the Mississinewa River at Marion, Indiana, 2013
Coon, William F.
2014-01-01
Digital flood-inundation maps for a 9-mile (mi) reach of the Mississinewa River from 0.75 mi upstream from the Pennsylvania Street bridge in Marion, Indiana, to 0.2 mi downstream from State Route 15 were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Mississinewa River at Marion (station number 03326500). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the current stage-discharge relation at the Mississinewa River streamgage, in combination with water-surface profiles from historic floods and from the current (2002) flood-insurance study for Grant County, Indiana. The hydraulic model was then used to compute seven water-surface profiles for flood stages at 1-fo (ft) intervals referenced to the streamgage datum and ranging from 10 ft, which is near bankfull, to 16 ft, which is between the water levels associated with the estimated 10- and 2-percent annual exceedance probability floods (floods with recurrence interval between 10 and 50 years) and equals the “major flood stage” as defined by the NWS. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging (lidar) data having a 0.98 ft vertical accuracy and 4.9 ft horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Overton, Jr., William C.; Steyert, Jr., William A.
1984-01-01
A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.
Overton, W.C. Jr.; Steyert, W.A. Jr.
1981-05-22
A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.
Flood-inundation maps for the Tippecanoe River at Winamac, Indiana
Menke, Chad D.; Bunch, Aubrey R.
2015-09-25
For this study, flood profiles were computed for the Tippecanoe River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Tippecanoe River streamgage, in combination with the current (2014) Federal Emergency Management Agency flood-insurance study for Pulaski County. The calibrated hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability (AEP) flood stage (flood with recurrence intervals within 100 years) has not been determined yet for this streamgage location. The rating has not been developed for the 1-percent AEP because the streamgage dates to only 2001. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 03331753, Tippecanoe River at Winamac, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Hoard, C.J.; Fowler, K.K.; Kim, M.H.; Menke, C.D.; Morlock, S.E.; Peppler, M.C.; Rachol, C.M.; Whitehead, M.T.
2010-01-01
Digital flood-inundation maps for a 15-mile reach of the Kalamazoo River from Marshall to Battle Creek, Michigan, were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Environmental Protection Agency to help guide remediation efforts following a crude-oil spill on July 25, 2010. The spill happened on Talmadge Creek, a tributary of the Kalamazoo River near Marshall, during a flood. The floodwaters transported the spilled oil down the Kalamazoo River and deposited oil in impoundments and on the surfaces of islands and flood plains. Six flood-inundation maps were constructed corresponding to the flood stage (884.09 feet) coincident with the oil spill on July 25, 2010, as well as for floods with annual exceedance probabilities of 0.2, 1, 2, 4, and 10 percent. Streamflow at the USGS streamgage at Marshall, Michigan (USGS site ID 04103500), was used to calculate the flood probabilities. From August 13 to 18, 2010, 35 channel cross sections, 17 bridges and 1 dam were surveyed. These data were used to construct a water-surface profile for the July 25, 2010, flood by use of a one-dimensional step-backwater model. The calibrated model was used to estimate water-surface profiles for other flood probabilities. The resulting six flood-inundation maps were created with a geographic information system by combining flood profiles with a 1.2-foot vertical and 10-foot horizontal resolution digital elevation model derived from Light Detection and Ranging data.
Dynamic Flood Vulnerability Mapping with Google Earth Engine
NASA Astrophysics Data System (ADS)
Tellman, B.; Kuhn, C.; Max, S. A.; Sullivan, J.
2015-12-01
Satellites capture the rate and character of environmental change from local to global levels, yet integrating these changes into flood exposure models can be cost or time prohibitive. We explore an approach to global flood modeling by leveraging satellite data with computing power in Google Earth Engine to dynamically map flood hazards. Our research harnesses satellite imagery in two main ways: first to generate a globally consistent flood inundation layer and second to dynamically model flood vulnerability. Accurate and relevant hazard maps rely on high quality observation data. Advances in publicly available spatial, spectral, and radar data together with cloud computing allow us to improve existing efforts to develop a comprehensive flood extent database to support model training and calibration. This talk will demonstrate the classification results of algorithms developed in Earth Engine designed to detect flood events by combining observations from MODIS, Landsat 8, and Sentinel-1. Our method to derive flood footprints increases the number, resolution, and precision of spatial observations for flood events both in the US, recorded in the NCDC (National Climatic Data Center) storm events database, and globally, as recorded events from the Colorado Flood Observatory database. This improved dataset can then be used to train machine learning models that relate spatial temporal flood observations to satellite derived spatial temporal predictor variables such as precipitation, antecedent soil moisture, and impervious surface. This modeling approach allows us to rapidly update models with each new flood observation, providing near real time vulnerability maps. We will share the water detection algorithms used with each satellite and discuss flood detection results with examples from Bihar, India and the state of New York. We will also demonstrate how these flood observations are used to train machine learning models and estimate flood exposure. The final stage of our comprehensive approach to flood vulnerability couples inundation extent with social data to determine which flood exposed communities have the greatest propensity for loss. Specifically, by linking model outputs to census derived social vulnerability estimates (Indian and US, respectively) to predict how many people are at risk.
Murphy, Elizabeth A.; Soong, David T.; Sharpe, Jennifer B.
2012-01-01
Digital flood-inundation maps for a 9-mile reach of the Des Plaines River from Riverwoods to Mettawa, Illinois, were created by the U.S. Geological Survey (USGS) in cooperation with the Lake County Stormwater Management Commission and the Villages of Lincolnshire and Riverwoods. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights) at the USGS streamgage at Des Plaines River at Lincolnshire, Illinois (station no. 05528100). Current conditions at the USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?05528100. In addition, this streamgage is incorporated into the Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/) by the National Weather Service (NWS). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. The NWS forecasted peak-stage information, also shown on the Des Plaines River at Lincolnshire inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was then used to determine seven water-surface profiles for flood stages at roughly 1-ft intervals referenced to the streamgage datum and ranging from the 50- to 0.2-percent annual exceedance probability flows. The simulated water-surface profiles were then combined with a Geographic Information System (GIS) Digital Elevation Model (DEM) (derived from Light Detection And Ranging (LiDAR) data) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage height from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-rich and flood-poor periods in Spain in 1942-2009
NASA Astrophysics Data System (ADS)
Mediero, Luis; Santillán, David; Garrote, Luis
2016-04-01
Several studies to detect trends in flood series at either national or trans-national scales have been conducted. Mediero et al. (2015) studied flood trends by using the longest streamflow records available in Europe. They found a decreasing trend in the Atlantic, Continental and Scandinavian regions. More specifically, Mediero et al. (2014) found a general decreasing trend in flood series in Spain in the period 1959-2009. Trends in flood series are usually detected by the Mann-Kendall test applied to a given period. However, the result of the Mann-Kendall test can change in terms of the starting and ending year of the series. Flood oscillations can occur and flood-rich and flood-poor periods could condition the results, especially when they are located at the beginning or end of the series. A methodology to identify statistically significant flood-rich and flood-poor periods is developed, based on the comparison between the expected sampling variability of floods when stationarity is assumed and the observed variability of floods in a given series. The methodology is applied to the longest series of annual maximum floods, peaks over threshold and counts of annual occurrences in peaks over threshold series observed in Spain in the period 1942-2009. A flood-rich period in 1950-1970 and a flood-poor period in 1970-1990 are identified in most of the selected sites. The generalised decreasing trend in flood series found by Mediero et al. (2014) could be explained by a flood-rich period placed at the beginning of the series and a flood-poor period located at the end of the series. References: Mediero, L., Kjeldsen, T.R., Macdonald, N., Kohnova, S., Merz, B., Vorogushyn, S., Wilson, D., Alburquerque, T., Blöschl, G., Bogdanowicz, E., Castellarin, A., Hall, J., Kobold, M., Kriauciuniene, J., Lang, M., Madsen, H., Onuşluel Gül, G., Perdigão, R.A.P., Roald, L.A., Salinas, J.L., Toumazis, A.D., Veijalainen, N., Óðinn Þórarinsson. Identification of coherent flood regions across Europe using the longest streamflow records, Journal of Hydrology, 528, 341-360, 2015. Mediero, L., Santillán, D., Garrote, L., Granados, A. Detection and attribution of trends in magnitude, frequency and timing of floods in Spain, Journal of Hydrology, 517, 1072-1088, 2014.
On the significance of future trends in flood frequencies
NASA Astrophysics Data System (ADS)
Bernhardt, M.; Schulz, K.; Wieder, O.
2015-12-01
Floods are a significant threat for alpine headwater catchments and for the forelands. The formation of significant flood events is thereby often coupled on processes occurring in the alpine zone. Rain on snow events are just one example. The prediction of flood risks or trends of flood risks is of major interest to people under direct threat, policy and decision makers as well as for insurance companies. A lot of research was and is currently done in view of detecting future trends in flood extremes or return periods. From a pure physically based point of view, there is strong evidence that those trends exist. But, the central point question is if trends in flood events or other extreme events could be detected from a statistical point of view and on the basis of the available data. This study will investigate this question on the basis of different target parameters and by using long term measurements.
Analyzing Flash Flood Data in an Ultra-Urban Region
NASA Astrophysics Data System (ADS)
Smith, B. K.; Rodriguez, S.
2016-12-01
New York City is an ultra-urban region, with combined sewers and buried stream channels. Traditional flood studies rely on the presence of stream gages to detect flood stage and discharge, but ultra-urban regions frequently lack the surface stream channels and gages necessary for this approach. In this study we aggregate multiple non-traditional data for detecting flash flood events. These data including phone call reports, city records, and, for one particular flood event, news reports and social media reports. These data are compared with high-resolution bias-corrected radar rainfall fields to study flash flood events in New York City. We seek to determine if these non-traditional data will allow for a comprehensive study of rainfall-runoff relationships in New York City. We also seek to map warm season rainfall heterogeneities in the city and to compare them to spatial distribution of reported flood occurrence.
Survey of computer vision-based natural disaster warning systems
NASA Astrophysics Data System (ADS)
Ko, ByoungChul; Kwak, Sooyeong
2012-07-01
With the rapid development of information technology, natural disaster prevention is growing as a new research field dealing with surveillance systems. To forecast and prevent the damage caused by natural disasters, the development of systems to analyze natural disasters using remote sensing geographic information systems (GIS), and vision sensors has been receiving widespread interest over the last decade. This paper provides an up-to-date review of five different types of natural disasters and their corresponding warning systems using computer vision and pattern recognition techniques such as wildfire smoke and flame detection, water level detection for flood prevention, coastal zone monitoring, and landslide detection. Finally, we conclude with some thoughts about future research directions.
Flood-inundation maps for an 8.9-mile reach of the South Fork Little River at Hopkinsville, Kentucky
Lant, Jeremiah G.
2013-01-01
Digital flood-inundation maps for an 8.9-mile reach of South Fork Little River at Hopkinsville, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Hopkinsville Community Development Services. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky (station no. 03437495). Current conditions for the USGS streamgage may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis/inventory?agency_code=USGS&site_no=03437495). In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the South Fork Little River reach by using HEC-RAS, a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (2012) stage-discharge relation at the South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky, streamgage and measurements collected during recent flood events. The calibrated model was then used to calculate 13 water-surface profiles for a sequence of flood stages, most at 1-foot intervals, referenced to the streamgage datum and ranging from a stage near bank full to the estimated elevation of the 1.0-percent annual exceedance probability flood at the streamgage. To delineate the flooded area at each interval flood stage, the simulated water-surface profiles were combined with a Digital Elevation Model (DEM) of the study area by using Geographic Information System (GIS) software. The DEM consisted of bare-earth elevations within the study area and was derived from a Light Detection And Ranging (LiDAR) dataset having a 3.28-foot horizontal resolution. These flood-inundation maps, along with online information regarding current stages from USGS streamgage and forecasted stages from the NWS, provide emergency management and local residents with critical information for flood response activities such as evacuations, road closures, and post-flood recovery efforts.
Flood and Fire Monitoring and Forecasting Within the Chornobyl Exclusion Zone
NASA Astrophysics Data System (ADS)
Los, Victor
2001-03-01
Taking into consideration that radioactivity from the contaminating elements of the Chernobyl Exclusion Zone (CEZ) amounts to a huge number, one of the most urgent tasks, at present, is the resolution of problems related to secondary radioactive contamination caused by floods and fires. These factors may lead to critical consequences. For instance, if radioactive contaminants migrate into the water system, namely into the Dnipro River, a threat arises to more than 20 million inhabitants of Ukraine. Additionally, fires in the CEZ potentially could cause contaminants to be dispersed into the air and to migrate in the atmosphere for long distances. The elements of information support system for administrative decision-making to respond to the appearances and consequences of forest fires and floods in contaminated areas of the CEZ have been developed. The system proposes: using Earth Remote Sensing (R/S) data for timely detection of forest fires; integration by Geographic Information System (GIS) of mathematical models for radionuclide migration by air in order to forecast radiological consequences of forest fires; forecasting and assessing flood consequences by means of spatial analysis of GIS and R/S; and development of a system for dissemination of information. This project was performed within the framework of USAID Cooperative Agreement #121-A-00-98-00615-00, dedicated to the establishment of the Ukrainian Land and Resource Management Center.
NASA Astrophysics Data System (ADS)
Tekeli, Ahmet Emre; Fouli, Hesham
2016-10-01
Floods are among the most common disasters harming humanity. In particular, flash floods cause hazards to life, property and any type of structures. Arid and semi-arid regions are equally prone to flash floods like regions with abundant rainfall. Despite rareness of intensive and frequent rainfall events over Kingdom of Saudi Arabia (KSA); an arid/semi-arid region, occasional flash floods occur and result in large amounts of damaging surface runoff. The flooding of 16 November, 2013 in Riyadh; the capital city of KSA, resulted in killing some people and led to much property damage. The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Real Time (RT) data (3B42RT) are used herein for flash flood forecasting. 3B42RT detected high-intensity rainfall events matching with the distribution of observed floods over KSA. A flood early warning system based on exceedance of threshold limits on 3B42RT data is proposed for Riyadh. Three different indexes: Constant Threshold (CT), Cumulative Distribution Functions (CDF) and Riyadh Flood Precipitation Index (RFPI) are developed using 14-year 3B42RT data from 2000 to 2013. RFPI and CDF with 90% captured the three major flooding events that occurred in February 2005, May 2010 and November 2013 in Riyadh. CT with 3 mm/h intensity indicated the 2013 flooding, but missed those of 2005 and 2010. The methodology implemented herein is a first-step simple and accurate way for flash flood forecasting over Riyadh. The simplicity of the methodology enables its applicability for the TRMM follow-on missions like Global Precipitation Measurement (GPM) mission.
Monitoring forests at the speed of light.
Valerie Rapp
2005-01-01
Airborne laser scanning is a technology developed in the last 15 years. Commonly referred to as light detection and ranging, or LIDAR, these systems can map ground with up to a 6-inch elevation accuracy in open, flat terrain. LIDAR is being rapidly adopted for topographical and flood-plain mapping and the detection of earthquake faults hidden by vegetation, among other...
Flood-inundation maps for the West Branch Delaware River, Delhi, New York, 2012
Coon, William F.; Breaker, Brian K.
2012-01-01
Digital flood-inundation maps for a 5-mile reach of the West Branch Delaware River through the Village and part of the Town of Delhi, New York, were created by the U.S. Geological Survey (USGS) in cooperation with the Village of Delhi, the Delaware County Soil and Water Conservation District, and the Delaware County Planning Department. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the Federal Flood Inundation Mapper Web site at http://wim.usgs.gov/FIMI/FloodInundationMapper.html, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) referenced to the USGS streamgage at West Branch Delaware River upstream from Delhi, N.Y. (station number 01421900). In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model that had been used to produce the flood insurance rate maps for the most recent flood insurance study for the Town and Village of Delhi. This hydraulic model was used to compute 10 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 7 ft or near bankfull to 16 ft, which exceeds the stages that correspond to both the estimated 0.2-percent annual-exceedance-probability flood (500-year recurrence interval flood) and the maximum recorded peak flow. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model, which was derived from Light Detection and Ranging (LiDAR) data with a 1.2-ft (0.61-ft root mean squared error) vertical accuracy and 3.3-ft (1-meter) horizontal resolution, to delineate the area flooded at each water level. A map that was produced using this method to delineate the inundated area for the flood that occurred on August 28, 2011, agreed well with highwater marks that had been located in the field using a global positioning system. The availability of the 10 flood-inundation maps on the USGS Flood Inundation Mapping Science Web site, along with Internet information regarding current stage from the USGS streamgage, will provide emergency management personnel and residents with information that is critical for flood-response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Application of GPR Method for Detection of Loose Zones in Flood Levee
NASA Astrophysics Data System (ADS)
Gołębiowski, Tomisław; Małysa, Tomasz
2018-02-01
In the paper the results of non-invasive georadar (GPR) surveys carried out for detection of loose zones located in the flood levee was presented. Terrain measurements were performed on the Vistula river flood levee in the village of Wawrzeńczyce near Cracow. In the investigation site, during the flood in 2010, leakages of levee were observed, so detection of inner water filtration paths was an important matter taking into account the stability of the levee during the next flood. GPR surveys had reconnaissance character, so they were carried out with the use of short-offset reflection profiling (SORP) technique and radargrams were subjected to standard signal processing. The results of surveys allowed to outline main loose zone in the levee which were the reason of leakages in 2010. Additionally gravel interbeddings in sand were detected which had an important influence, due to higher porosity of such zones, to water filtration inside of the levee. In the paper three solutions which allow to increase quality and resolution of radargrams were presented, i.e. changeable-polarisation surveys, advanced signal processing and DHA procedure.
Identification and delineation of areas flood hazard using high accuracy of DEM data
NASA Astrophysics Data System (ADS)
Riadi, B.; Barus, B.; Widiatmaka; Yanuar, M. J. P.; Pramudya, B.
2018-05-01
Flood incidents that often occur in Karawang regency need to be mitigated. These expectations exist on technologies that can predict, anticipate and reduce disaster risks. Flood modeling techniques using Digital Elevation Model (DEM) data can be applied in mitigation activities. High accuracy DEM data used in modeling, will result in better flooding flood models. The result of high accuracy DEM data processing will yield information about surface morphology which can be used to identify indication of flood hazard area. The purpose of this study was to identify and describe flood hazard areas by identifying wetland areas using DEM data and Landsat-8 images. TerraSAR-X high-resolution data is used to detect wetlands from landscapes, while land cover is identified by Landsat image data. The Topography Wetness Index (TWI) method is used to detect and identify wetland areas with basic DEM data, while for land cover analysis using Tasseled Cap Transformation (TCT) method. The result of TWI modeling yields information about potential land of flood. Overlay TWI map with land cover map that produces information that in Karawang regency the most vulnerable areas occur flooding in rice fields. The spatial accuracy of the flood hazard area in this study was 87%.
Flood-inundation maps for the DuPage River from Plainfield to Shorewood, Illinois, 2013
Murphy, Elizabeth A.; Sharpe, Jennifer B.
2013-01-01
Digital flood-inundation maps for a 15.5-mi reach of the DuPage River from Plainfield to Shorewood, Illinois, were created by the U.S. Geological Survey (USGS) in cooperation with the Will County Stormwater Management Planning Committee. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights or stages) at the USGS streamgage at DuPage River at Shorewood, Illinois (sta. no. 05540500). Current conditions at the USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?05540500. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. The NWS-forecasted peak-stage information, also shown on the DuPage River at Shorewood inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-ft intervals referenced to the streamgage datum and ranging from NWS Action stage of 6 ft to the historic crest of 14.0 ft. The simulated water-surface profiles were then combined with a Digital Elevation Model (DEM) (derived from Light Detection And Ranging (LiDAR) data) by using a Geographic Information System (GIS) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage height from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for postflood recovery efforts.
Initial Results in Global Flood Monitoring System (GFMS) Using GPM Data
NASA Astrophysics Data System (ADS)
Wu, H.; Adler, R. F.; Kirschbaum, D.; Huffman, G. J.; Tian, Y.
2016-12-01
The Global Flood Monitoring System (GFMS) (http://flood.umd.edu) has been developed and used to provide real-time flood detection and streamflow estimates over the last few years with significant success shown by validation against global flood event data sets and observed streamflow variations. It has become a tool for various national and international organizations to appraise flood conditions in various areas, including where rainfall and hydrology information is limited. The GFMS has been using the TRMM Multi-satellite Precipitation Analysis (TMPA) as its main rainfall input. Now, with the advent of NASA's Global Precipitation Measurement (GPM) mission there is an opportunity to significantly improve global flood monitoring and forecasting. GPM's Integrated Multi-satellitE Retrievals for GPM (IMERG) multi-satellite product is designed to take advantage of various technical advances in the field and combine that with an efficient processing system producing "early" (4 hrs) and "late" (12 hrs) products for operational use. The products are also more uniform in results than TMPA among the various satellites going into the analysis and available at finer time and space resolutions. On the road to replacing TMPA with the IMERG in the operational version of the GFMS parallel systems were run for periods to understand the impact of the new type of data on the streamflow and flood estimates. Results of this comparison are the basis for this presentation. It is expected that an improvement will be noted both in the accuracy of the precipitation estimates and a smoother transition in and out of heavy rain events, helping to reduce "shock" in the hydrology model. The finer spatial resolution should also help in this regard. The GFMS will be initially run at its primary resolution of 1/8th degree latitude/longitude with both data sets to isolate the impact of the rain information change. Other aspects will also be examined, including higher latitude events, where GPM precipitation algorithms should also provide improvements. This initial work will help focus full implementation of the IMERG into GFMS and the retrospective calculations to be done for the full TRMM/GPM era.
Boldt, Justin A.
2018-01-16
A two-dimensional hydraulic model and digital flood‑inundation maps were developed for a 30-mile reach of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois. The flood-inundation maps, which can be accessed through the U.S. Geological Survey (USGS) Flood Inundation Mapping Science web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Wabash River at Mount Carmel, Ill (USGS station number 03377500). Near-real-time stages at this streamgage may be obtained on the internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS) at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS AHPS site MCRI2). The NWS AHPS forecasts peak stage information that may be used with the maps developed in this study to show predicted areas of flood inundation.Flood elevations were computed for the Wabash River reach by means of a two-dimensional, finite-volume numerical modeling application for river hydraulics. The hydraulic model was calibrated by using global positioning system measurements of water-surface elevation and the current stage-discharge relation at both USGS streamgage 03377500, Wabash River at Mount Carmel, Ill., and USGS streamgage 03378500, Wabash River at New Harmony, Indiana. The calibrated hydraulic model was then used to compute 27 water-surface elevations for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from less than the action stage (9 ft) to the highest stage (35 ft) of the current stage-discharge rating curve. The simulated water‑surface elevations were then combined with a geographic information system digital elevation model, derived from light detection and ranging data, to delineate the area flooded at each water level.The availability of these maps, along with information on the internet regarding current stage from the USGS streamgage at Mount Carmel, Ill., and forecasted stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood-response activities such as evacuations and road closures, as well as for postflood recovery efforts.
The 3D Elevation Program—Flood risk management
Carswell, William J.; Lukas, Vicki
2018-01-25
Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design and operation of such structures, (2) provide more accurate and accessible flood forecasting, and (3) shift the Federal Emergency Management Agency (FEMA) National Flood Insurance Program to a more balanced, less costly flood-insurance paradigm. Expanding the availability and use of high-quality, three-dimensional (3D) elevation information derived from modern light detection and ranging (lidar) technologies to provide essential terrain data poses a singular opportunity to dramatically enhance the effectiveness of all three components of this strategy. Additionally, FEMA, the National Weather Service, and the U.S. Geological Survey (USGS) have developed tools and joint program activities to support the national strategy.The USGS 3D Elevation Program (3DEP) has the programmatic infrastructure to produce and provide essential terrain data. This infrastructure includes (1) data acquisition partnerships that leverage funding and reduce duplicative efforts, (2) contracts with experienced private mapping firms that ensure acquisition of consistent, low-cost 3D elevation data, and (3) the technical expertise, standards, and specifications required for consistent, edge-to-edge utility across multiple collection platforms and public access unfettered by individual database designs and limitations.High-quality elevation data, like that collected through 3DEP, are invaluable for assessing and documenting flood risk and communicating detailed information to both responders and planners alike. Multiple flood-mapping programs make use of USGS streamflow and 3DEP data. Flood insurance rate maps, flood documentation studies, and flood-inundation map libraries are products of these programs.
Benedict, Stephen T.; Caldwell, Andral W.; Clark, Jimmy M.
2013-01-01
Digital flood-inundation maps for a 3.95-mile reach of the Saluda River from approximately 815 feet downstream from Old Easley Bridge Road to approximately 150 feet downstream from Saluda Lake Dam near Greenville, South Carolina, were developed by the U.S. Geological Survey (USGS). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Saluda River near Greenville, South Carolina (station 02162500). Current conditions at the USGS streamgage may be obtained through the National Water Information System Web site at http://waterdata.usgs.gov/sc/nwis/uv/?site_no=02162500&PARAmeter_cd=00065,00060,00062. The National Weather Service (NWS) forecasts flood hydrographs at many places that are often collocated with USGS streamgages. Forecasted peak-stage information is available on the Internet at the NWS Advanced Hydrologic Prediction Service (AHPS) flood-warning system Web site (http://water.weather.gov/ahps/) and may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation.In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-streamflow relations at USGS streamgage station 02162500, Saluda River near Greenville, South Carolina. The hydraulic model was then used to determine water-surface profiles for flood stages at 1.0-foot intervals referenced to the streamgage datum and ranging from approximately bankfull to 2 feet higher than the highest recorded water level at the streamgage. The simulated water-surface profiles were then exported to a geographic information system, ArcGIS, and combined with a digital elevation model (derived from Light Detection and Ranging [LiDAR] data with a 0.6-foot vertical Root Mean Square Error [RMSE] and a 3.0-foot horizontal RMSE), using HEC-GeoRAS tools in order to delineate the area flooded at each water level. The availability of these maps, along with real-time stage data from the USGS streamgage station 02162500 and forecasted stream stages from the NWS, can provide emergency management personnel and residents with information that is critical during flood-response and flood-recovery activities, such as evacuations, road closures, and disaster declarations.
High Resolution Sensing and Control of Urban Water Networks
NASA Astrophysics Data System (ADS)
Bartos, M. D.; Wong, B. P.; Kerkez, B.
2016-12-01
We present a framework to enable high-resolution sensing, modeling, and control of urban watersheds using (i) a distributed sensor network based on low-cost cellular-enabled motes, (ii) hydraulic models powered by a cloud computing infrastructure, and (iii) automated actuation valves that allow infrastructure to be controlled in real time. This platform initiates two major advances. First, we achieve a high density of measurements in urban environments, with an anticipated 40+ sensors over each urban area of interest. In addition to new measurements, we also illustrate the design and evaluation of a "smart" control system for real-world hydraulic networks. This control system improves water quality and mitigates flooding by using real-time hydraulic models to adaptively control releases from retention basins. We evaluate the potential of this platform through two ongoing deployments: (i) a flood monitoring network in the Dallas-Fort Worth metropolitan area that detects and anticipates floods at the level of individual roadways, and (ii) a real-time hydraulic control system in the city of Ann Arbor, MI—soon to be one of the most densely instrumented urban watersheds in the United States. Through these applications, we demonstrate that distributed sensing and control of water infrastructure can improve flash flood predictions, emergency response, and stormwater contaminant mitigation.
44 CFR 60.3 - Flood plain management criteria for flood-prone areas.
Code of Federal Regulations, 2012 CFR
2012-10-01
... minimize or eliminate infiltration of flood waters into the systems; and (6) Require within flood-prone... infiltration of flood waters into the systems and discharges from the systems into flood waters and (ii) onsite...
44 CFR 60.3 - Flood plain management criteria for flood-prone areas.
Code of Federal Regulations, 2014 CFR
2014-10-01
... minimize or eliminate infiltration of flood waters into the systems; and (6) Require within flood-prone... infiltration of flood waters into the systems and discharges from the systems into flood waters and (ii) onsite...
44 CFR 60.3 - Flood plain management criteria for flood-prone areas.
Code of Federal Regulations, 2013 CFR
2013-10-01
... minimize or eliminate infiltration of flood waters into the systems; and (6) Require within flood-prone... infiltration of flood waters into the systems and discharges from the systems into flood waters and (ii) onsite...
Rendon, Samuel H.; Ashworth, Chad E.; Smith, S. Jerrod
2012-01-01
Dams provide beneficial functions such as flood control, recreation, and reliable water supplies, but they also entail risk: dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or misoperation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. Accurate topographic data are vital for developing flood-inundation maps. This report presents results of a cooperative study by the city of Lawton, Oklahoma, and the U.S. Geological Survey (USGS) to model dam-breach scenarios at Lakes Ellsworth and Lawtonka near Lawton and to map the potential flood-inundation areas of such dam breaches. To assist the city of Lawton with completion of the emergency action plans for Lakes Ellsworth and Lawtonka Dams, the USGS collected light detection and ranging (lidar) data that were used to develop a high-resolution digital elevation model and a 1-foot contour elevation map for the flood plains downstream from Lakes Ellsworth and Lawtonka. This digital elevation model and field measurements, streamflow-gaging station data (USGS streamflow-gaging station 07311000, East Cache Creek near Walters, Okla.), and hydraulic values were used as inputs for the dynamic (unsteady-flow) model, Hydrologic Engineering Center's River Analysis System (HEC-RAS). The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum flood scenario and a sunny-day dam-breach scenario, as well as for maximum flood-inundation elevations and flood-wave arrival times for selected bridge crossings. Some areas of concern near the city of Lawton, if a dam breach occurs at Lakes Ellsworth or Lawtonka, include water treatment plants, wastewater treatment plants, recreational areas, and community-services offices.
Flood-inundation maps for the Patoka River in and near Jasper, southwestern Indiana
Fowler, Kathleen K.
2018-01-23
Digital flood-inundation maps for a 9.5-mile reach of the Patoka River in and near the city of Jasper, southwestern Indiana (Ind.), from the streamgage near County Road North 175 East, downstream to State Road 162, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science web site at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage Patoka River at Jasper, Ind. (station number 03375500). The Patoka streamgage is located at the upstream end of the 9.5-mile river reach. Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, although flood forecasts and stages for action and minor, moderate, and major flood stages are not currently (2017) available at this site (JPRI3).Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Patoka River at Jasper, Ind., streamgage and the documented high-water marks from the flood of April 30, 2017. The calibrated hydraulic model was then used to compute five water-surface profiles for flood stages referenced to the streamgage datum ranging from 15 feet (ft), or near bankfull, to 19 ft. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging [lidar] data having a 0.98 ft vertical accuracy and 4.9 ft horizontal resolution) to delineate the area flooded at each water level.The availability of these flood-inundation maps, along with real-time stage from the USGS streamgage at the Patoka River at Jasper, Ind., will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for postflood recovery efforts.
Flood-inundation maps for the North Branch Elkhart River at Cosperville, Indiana
Kim, Moon H.; Johnson, Esther M.
2014-01-01
Digital flood-inundation maps for a reach of the North Branch Elkhart River at Cosperville, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Army Corps of Engineers, Detroit District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 04100222, North Branch Elkhart River at Cosperville, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=04100222. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many places that are often colocated with USGS streamgages, including the North Branch Elkhart River at Cosperville, Ind. NWS AHPS-forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the North Branch Elkhart River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 04100222, North Branch Elkhart River at Cosperville, Ind., and preliminary high-water marks from the flood of March 1982. The calibrated hydraulic model was then used to determine four water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [LiDAR]) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 04100222, North Branch Elkhart River at Cosperville, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the St. Joseph River at Elkhart, Indiana
Martin, Zachary W.
2017-02-01
Digital flood-inundation maps for a 6.6-mile reach of the St. Joseph River at Elkhart, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind. Real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at https://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS site EKMI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current stage-discharge rating at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind., and the documented high-water marks from the flood of March 1982. The hydraulic model was then used to compute six water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum ranging from 23.0 ft (the NWS “action stage”) to 28.0 ft, which is the highest stage interval of the current USGS stage-discharge rating curve and 1 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging [lidar] data having a 0.49-ft root mean squared error and 4.9-ft horizontal resolution, resampled to a 10-ft grid) to delineate the area flooded at each stage.The availability of these maps, along with Internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-Inundation Maps for Sugar Creek at Crawfordsville, Indiana
Martin, Zachary W.
2016-06-06
Digital flood-inundation maps for a 6.5-mile reach of Sugar Creek at Crawfordsville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 03339500, Sugar Creek at Crawfordsville, Ind. Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS site CRWI3).Flood profiles were computed for the USGS streamgage 03339500, Sugar Creek at Crawfordsville, Ind., reach by means of a one-dimensional step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current stage-discharge rating at the USGS streamgage 03339500, Sugar Creek at Crawfordsville, Ind., and high-water marks from the flood of April 19, 2013, which reached a stage of 15.3 feet. The hydraulic model was then used to compute 13 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum ranging from 4.0 ft (the NWS “action stage”) to 16.0 ft, which is the highest stage interval of the current USGS stage-discharge rating curve and 2 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging [lidar]) data having a 0.49-ft root mean squared error and 4.9-ft horizontal resolution) to delineate the area flooded at each stage.The availability of these maps, along with Internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Guy, A C; Desutter, T M; Casey, F X M; Kolka, R; Hakk, H
2012-01-01
Spring flooding of the Red River of the North (RR) is common, but little information exits on how these flood events affect water and overbank sediment quality within an urban area. With the threat of the spring 2009 flood in the RR predicted to be the largest in recorded history and the concerns about the flooding of farmsteads, outbuildings, garages, and basements, the objectives of this study, which focused on Fargo, ND, and Moorhead, MN, were to assess floodwater quality and to determine the quantity and quality of overbank sediment deposited after floodwaters recede and the quality of soil underlying sediment deposits. 17β-Estradiol was detected in 9 of 24 water samples, with an average concentration of 0.61 ng L. Diesel-range organics were detected in 8 of 24 samples, with an average concentration of 80.0 μg L. The deposition of sediment across locations and transects ranged from 2 to 10 kg m, and the greatest mass deposition of chemicals was closest to the river channel. No gasoline-range organics were detected, but diesel-range organics were detected in 26 of the 27 overbank sediment samples (maximum concentration, 49.2 mg kg). All trace elements detected in the overbank sediments were within ranges for noncontaminated sites. Although flooding has economic, social, and environmental impacts, based on the results of this study, it does not appear that flooding in the RR in F-M led to decreased quality of water, sediment, or soil compared with normal river flows or resident soil. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Flood-inundation maps for the Flatrock River at Columbus, Indiana, 2012
Coon, William F.
2013-01-01
Digital flood-inundation maps for a 5-mile reach of the Flatrock River on the western side of Columbus, Indiana, from County Road 400N to the river mouth at the confluence with Driftwood River, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the Federal Flood Inundation Mapper Web site at http://wim.usgs.gov/FIMI/FloodInundationMapper.html, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Flatrock River at Columbus (station number 03363900). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service, which also presents the USGS data, at http:/water.weather.gov/ahps/. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation at the Flatrock River streamgage, high-water marks that were surveyed following the flood of June 7, 2008, and water-surface profiles from the current flood-insurance study for the City of Columbus. The hydraulic model was then used to compute 12 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 9 ft or near bankfull to 20 ft, which exceeds the stages that correspond to both the estimated 0.2-percent annual exceedance probability flood (500-year recurrence interval flood) and the maximum recorded peak flow. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from Light Detection and Ranging (LiDAR) data having a 0.37 ft vertical accuracy and 3.9 ft horizontal resolution) to delineate the area flooded at each water level. The availability of these maps on the USGS Federal Flood Inundation Mapper Web site, along with Internet information regarding current stage from the USGS streamgage, will provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Roland, Mark A.; Hoffman, Scott A.
2014-01-01
Digital flood-inundation maps for an approximate 8-mile reach of the West Branch Susquehanna River from approximately 2 miles downstream from the Borough of Lewisburg, extending upstream to approximately 1 mile upstream from the Borough of Milton, Pennsylvania, were created by the U.S. Geological Survey (USGS) in cooperation with the Susquehanna River Basin Commission (SRBC). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict the estimated areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa. In addition, the information has been provided to the Susquehanna River Basin Commission (SRBC) for incorporation into their Susquehanna Inundation Map Viewer (SIMV) flood warning system (http://maps.srbc.net/simv/). The National Weather Service (NWS) forecasted peak-stage information (http://water.weather.gov/ahps) for USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa., may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. Calibration of the model was achieved using the most current stage-discharge relations (rating number 11.1) at USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa., a documented water-surface profile from the December 2, 2010, flood, and recorded peak stage data. The hydraulic model was then used to determine 26 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum ranging from 14 feet (ft) to 39 ft. Modeled flood stages, as defined by NWS, include Action Stage, 14 ft; Flood Stage, 18 ft; Moderate Flood Stage, 23 ft; and Major Flood Stage, 28 ft. Geographic information system (GIS) technology was then used to combine the simulated water-surface profiles with a digital elevation model (DEM) derived from light detection and ranging (lidar) data to delineate the area flooded at each water level. The availability of these maps, along with World Wide Web information regarding current stage from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the Yellow River at Plymouth, Indiana
Menke, Chad D.; Bunch, Aubrey R.; Kim, Moon H.
2016-11-16
Digital flood-inundation maps for a 4.9-mile reach of the Yellow River at Plymouth, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 05516500, Yellow River at Plymouth, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=05516500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http:/water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many sites that are often collocated with USGS streamgages, including the Yellow River at Plymouth, Ind. NWS AHPS-forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood and forecasts of flood hydrographs at this site.For this study, flood profiles were computed for the Yellow River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the current stage-discharge relations at the Yellow River streamgage, in combination with the flood-insurance study for Marshall County (issued in 2011). The calibrated hydraulic model was then used to determine eight water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability flood profile elevation (flood elevation with recurrence intervals within 100 years) is within the calibrated water-surface elevations for comparison. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level.The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 05516500, Yellow River at Plymouth, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for postflood recovery efforts.
NASA Astrophysics Data System (ADS)
Hostache, Renaud; Chini, Marco; Matgen, Patrick; Giustarini, Laura
2013-04-01
There is a clear need for developing innovative processing chains based on earth observation (EO) data to generate products supporting emergency response and flood management at a global scale. Here an automatic flood mapping application is introduced. The latter is currently hosted on the Grid Processing on Demand (G-POD) Fast Access to Imagery (Faire) environment of the European Space Agency. The main objective of the online application is to deliver flooded areas using both recent and historical acquisitions of SAR data in an operational framework. It is worth mentioning that the method can be applied to both medium and high resolution SAR images. The flood mapping application consists of two main blocks: 1) A set of query tools for selecting the "crisis image" and the optimal corresponding pre-flood "reference image" from the G-POD archive. 2) An algorithm for extracting flooded areas using the previously selected "crisis image" and "reference image". The proposed method is a hybrid methodology, which combines histogram thresholding, region growing and change detection as an approach enabling the automatic, objective and reliable flood extent extraction from SAR images. The method is based on the calibration of a statistical distribution of "open water" backscatter values inferred from SAR images of floods. Change detection with respect to a pre-flood reference image helps reducing over-detection of inundated areas. The algorithms are computationally efficient and operate with minimum data requirements, considering as input data a flood image and a reference image. Stakeholders in flood management and service providers are able to log onto the flood mapping application to get support for the retrieval, from the rolling archive, of the most appropriate pre-flood reference image. Potential users will also be able to apply the implemented flood delineation algorithm. Case studies of several recent high magnitude flooding events (e.g. July 2007 Severn River flood, UK and March 2010 Red River flood, US) observed by high-resolution SAR sensors as well as airborne photography highlight advantages and limitations of the online application. A mid-term target is the exploitation of ESA SENTINEL 1 SAR data streams. In the long term it is foreseen to develop a potential extension of the application for systematically extracting flooded areas from all SAR images acquired on a daily, weekly or monthly basis. On-going research activities investigate the usefulness of the method for mapping flood hazard at global scale using databases of historic SAR remote sensing-derived flood inundation maps.
Flynn, Robert H.
2014-01-01
In addition to the two digital flood inundation maps, flood profiles were created that depict the study reach flood elevation of tropical storm Irene of August 2011 and the 10-, 2-, 1-, and 0.2-percent AEP floods, also known as the 10-, 50-, 100-, and 500-year floods, respectively. The 10-, 2-, 1-, and 0.2-percent AEP flood discharges were determined using annual peak flow data from the USGS Ottauquechee River near West Bridgewater, Vt. streamgage (station 01150900). Flood profiles were computed for the Ottauquechee River and Reservoir Brook by means of a one-dimensional step-backwater model. The model was calibrated using documented high-water marks of the peak of the tropical storm Irene flood of August 2011 as well as stage discharge data as determined for USGS Ottauquechee River near West Bridgewater, Vt. streamgage (station 01150900). The simulated water-surface profiles were combined with a digital elevation model within a geographic information system to delineate the areas flooded during tropical storm Irene and for the 1-percent AEP water-surface profile. The digital elevation model data were derived from light detection and ranging (lidar) data obtained for a 3,281-foot (1,000-meter) corridor along the Ottauquechee River study reach and were augmented with 33-foot (10- meter) contour interval data in the modeled flood-inundation areas outside the lidar corridor. The 33-foot (10-meter) contour interval USGS 15-minute quadrangle topographic digital raster graphics map used to augment lidar data was produced at a scale of 1:24,000. The digital flood inundation maps and flood profiles along with information regarding current stage from USGS streamgages on the Internet provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Fifty-year flood-inundation maps for El Progreso, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of El Progreso that would be inundated by a 50-year flood of Rio Pelo. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of El Progreso as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood on Rio Pelo at El Progreso were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. There are no nearby long-term stream-gaging stations on Rio Pelo; therefore, the 50-year-flood discharge for Rio Pelo, 235 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The drainage area and mean annual precipitation estimated for Rio Pelo at El Progreso are 47.4 square kilometers and 1,920 millimeters, respectively.
Fifty-year flood-inundation maps for Choloma, Honduras
Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Choloma that would be inundated by a 50-year flood of Rio Choloma. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Choloma as part of the in the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood on Rio Choloma at Choloma were determined using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light detection and ranging (LIDAR) topographic survey of the area. There are no nearby long-term stream-gaging stations on Rio Choloma; therefore, the 50-year-flood discharge for Rio Choloma, 370 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The drainage area and mean annual precipitation estimated for Rio Choloma at Choloma are 89.5 square kilometers and 2,164 millimeters, respectively.
Fifty-year flood-inundation maps for Catacamas, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Catacamas that would be inundated by a 50-year-flood of Rio Catacamas. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Catacamas as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/ floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood on Rio Catacamas at Catacamas were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. The 50-year-flood discharge for Rio Catacamas at Catacamas, 216 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation because there are no long-term stream-gaging stations on the river from which to estimate the discharge. The drainage area and mean annual precipitation estimated for Rio Catacamas at Catacamas are 45.4 square kilometers and 1,773 millimeters, respectively.
Fifty-year flood-inundation maps for Olanchito, Honduras
Kresch, David L.; Mastin, M.C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Olanchito that would be inundated by a 50-year-flood of Rio Uchapa. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Olanchito as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood discharge of 243 cubic meters per second on Rio Uchapa at Olanchito were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. There are no nearby long-term stream-gaging stations on Rio Uchapa; therefore, the 50-year-flood discharge for Rio Uchapa was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The drainage area and mean annual precipitation estimated for Rio Uchapa at Olanchito are 97.1 square kilometers and 1,178 millimeters, respectively.
Fifty-year flood-inundation maps for La Ceiba, Honduras
Kresch, David L.; Mastin, M.C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of La Ceiba that would be inundated by a 50-year-flood of Rio Cangrejal. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of La Ceiba as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood discharge of 1,030 cubic meters per second on Rio Cangrejal at La Ceiba were computed using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. There are no nearby long-term stream-gaging stations on Rio Cangrejal; therefore, the 50-year-flood discharge for Rio Cangrejal at La Ceiba was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The drainage area and mean annual precipitation estimated for Rio Cangrejal at La Ceiba are 498 square kilometers and 2,306 millimeters, respectively.
Kiage, L.M.; Walker, N.D.; Balasubramanian, S.; Babin, A.; Barras, J.
2005-01-01
The Louisiana coast is subjected to hurricane impacts including flooding of human settlements, river channels and coastal marshes, and salt water intrusion. Information on the extent of flooding is often required quickly for emergency relief, repairs of infrastructure, and production of flood risk maps. This study investigates the feasibility of using Radarsat-1 SAR imagery to detect flooded areas in coastal Louisiana after Hurricane Lili, October 2002. Arithmetic differencing and multi-temporal enhancement techniques were employed to detect flooding and to investigate relationships between backscatter and water level changes. Strong positive correlations (R2=0.7-0.94) were observed between water level and SAR backscatter within marsh areas proximate to Atchafalaya Bay. Although variations in elevation and vegetation type did influence and complicate the radar signature at individual sites, multi-date differences in backscatter largely reflected the patterns of flooding within large marsh areas. Preliminary analyses show that SAR imagery was not useful in mapping urban flooding in New Orleans after Hurricane Katrina's landfall on 29 August 2005. ?? 2005 Taylor & Francis.
A Global Geospatial Database of 5000+ Historic Flood Event Extents
NASA Astrophysics Data System (ADS)
Tellman, B.; Sullivan, J.; Doyle, C.; Kettner, A.; Brakenridge, G. R.; Erickson, T.; Slayback, D. A.
2017-12-01
A key dataset that is missing for global flood model validation and understanding historic spatial flood vulnerability is a global historical geo-database of flood event extents. Decades of earth observing satellites and cloud computing now make it possible to not only detect floods in near real time, but to run these water detection algorithms back in time to capture the spatial extent of large numbers of specific events. This talk will show results from the largest global historical flood database developed to date. We use the Dartmouth Flood Observatory flood catalogue to map over 5000 floods (from 1985-2017) using MODIS, Landsat, and Sentinel-1 Satellites. All events are available for public download via the Earth Engine Catalogue and via a website that allows the user to query floods by area or date, assess population exposure trends over time, and download flood extents in geospatial format.In this talk, we will highlight major trends in global flood exposure per continent, land use type, and eco-region. We will also make suggestions how to use this dataset in conjunction with other global sets to i) validate global flood models, ii) assess the potential role of climatic change in flood exposure iii) understand how urbanization and other land change processes may influence spatial flood exposure iv) assess how innovative flood interventions (e.g. wetland restoration) influence flood patterns v) control for event magnitude to assess the role of social vulnerability and damage assessment vi) aid in rapid probabilistic risk assessment to enable microinsurance markets. Authors on this paper are already using the database for the later three applications and will show examples of wetland intervention analysis in Argentina, social vulnerability analysis in the USA, and micro insurance in India.
Towards flash-flood prediction in the dry Dead Sea region utilizing radar rainfall information
NASA Astrophysics Data System (ADS)
Morin, Efrat; Jacoby, Yael; Navon, Shilo; Bet-Halachmi, Erez
2009-07-01
Flash-flood warning models can save lives and protect various kinds of infrastructure. In dry climate regions, rainfall is highly variable and can be of high-intensity. Since rain gauge networks in such areas are sparse, rainfall information derived from weather radar systems can provide useful input for flash-flood models. This paper presents a flash-flood warning model which utilizes radar rainfall data and applies it to two catchments that drain into the dry Dead Sea region. Radar-based quantitative precipitation estimates (QPEs) were derived using a rain gauge adjustment approach, either on a daily basis (allowing the adjustment factor to change over time, assuming available real-time gauge data) or using a constant factor value (derived from rain gauge data) over the entire period of the analysis. The QPEs served as input for a continuous hydrological model that represents the main hydrological processes in the region, namely infiltration, flow routing and transmission losses. The infiltration function is applied in a distributed mode while the routing and transmission loss functions are applied in a lumped mode. Model parameters were found by calibration based on the 5 years of data for one of the catchments. Validation was performed for a subsequent 5-year period for the same catchment and then for an entire 10-year record for the second catchment. The probability of detection and false alarm rates for the validation cases were reasonable. Probabilistic flash-flood prediction is presented applying Monte Carlo simulations with an uncertainty range for the QPEs and model parameters. With low probability thresholds, one can maintain more than 70% detection with no more than 30% false alarms. The study demonstrates that a flash-flood warning model is feasible for catchments in the area studied.
Towards flash flood prediction in the dry Dead Sea region utilizing radar rainfall information
NASA Astrophysics Data System (ADS)
Morin, E.; Jacoby, Y.; Navon, S.; Bet-Halachmi, E.
2009-04-01
Flash-flood warning models can save lives and protect various kinds of infrastructure. In dry climate regions, rainfall is highly variable and can be of high-intensity. Since rain gauge networks in such areas are sparse, rainfall information derived from weather radar systems can provide useful input for flash-flood models. This paper presents a flash-flood warning model utilizing radar rainfall data and applies it to two catchments that drain into the dry Dead Sea region. Radar-based quantitative precipitation estimates (QPEs) were derived using a rain gauge adjustment approach, either on a daily basis (allowing the adjustment factor to change over time, assuming available real-time gauge data) or using a constant factor value (derived from rain gauge data) over the entire period of the analysis. The QPEs served as input for a continuous hydrological model that represents the main hydrological processes in the region, namely infiltration, flow routing and transmission losses. The infiltration function is applied in a distributed mode while the routing and transmission loss functions are applied in a lumped mode. Model parameters were found by calibration based on five years of data for one of the catchments. Validation was performed for a subsequent five-year period for the same catchment and then for an entire ten year record for the second catchment. The probability of detection and false alarm rates for the validation cases were reasonable. Probabilistic flash-flood prediction is presented applying Monte Carlo simulations with an uncertainty range for the QPEs and model parameters. With low probability thresholds, one can maintain more than 70% detection with no more than 30% false alarms. The study demonstrates that a flash-flood-warning model is feasible for catchments in the area studied.
NASA AIRS Detects Extent of Pakistan Flooding
2010-08-19
This image from NASA Aqua spacecraft shows how surface emissivity -- how efficiently Earth surface radiates heat -- changed in several regions of Pakistan over a 32-day period between July 11 pre-flood and August 12 post-flood.
A global hydrographic array for early detection of floods and droughts
NASA Astrophysics Data System (ADS)
Brakenridge, G.; Nghiem, S.; Caquard, S.
An array of over 700 20 km-long river gaging reaches, distributed world-wide, is imaged by the SeaWinds radar scatterometer aboard QuikSCAT every 2.5 days. Strongly negative HH/VV polarity ratios indicate large amounts of surface water. We set individual reach thresholds so that the transition from bankfull to overbank river flow can be identified according to changes in this ratio. Similarly, the wide-swath MODIS optical sensors provide frequent repeat coverage of the reaches at much higher spatial resolution (250 m). In this case, several reach water surface area thresholds can be identified: low flow or drought conditions, normal in-channel flow, overbank flow, and extreme flood conditions. Sustained data collection for the reaches by both sensors allows the radar response to changing surface water to be defined, and allows evaluation of the sensitivity of the MODIS data to river discharge changes. New approaches, such as ``unmixing'' analysis of mixed water/land MODIS pixels can extend detection limits to smaller rivers and streams. It is now possible for wide-area, frequent revisit terrestrial remote sensing to provide human society with early warning of both floods and droughts and by direct observation of the runoff component of the Earth's hydrologic cycle. Examples of both radar and optical approaches towards this end are at the web sites below: http://www.dartmouth.edu/˜ floods/Modisrapidresponse.html http://www.dartmouth.edu/˜ floods/sensorweb/SensorWebindex.html http://www.dartmouth.edu/˜ floods/Quikscat/Regional2/CurrentTisza.jpg} In particular, early flood detection results are obtained over an extensive region in eastern Europe including the Tisza River basin, Romania, Hungary, and adjacent nations. Flood detection maps are updated weekly at the web site. The combination of QuikSCAT and MODIS takes advantage of the large-area coverage of these sensors together with the high temporal resolution of QuikSCAT and the high spatial resolution of MODIS. Such capabilities are also appropriate for early flood detection in Asian monsoon regions including India, Pakistan, Bangladesh, China, and southeast Asia.
Flood-inundation maps for North Fork Salt Creek at Nashville, Indiana
Martin, Zachary W.
2017-11-13
Digital flood-inundation maps for a 3.2-mile reach of North Fork Salt Creek at Nashville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding that correspond to selected water levels (stages) at the North Fork Salt Creek at Nashville, Ind., streamgage (USGS station number 03371650). Real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also shows observed USGS stages at the same site as the USGS streamgage (NWS site NFSI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current (2015) stage-discharge rating at the USGS streamgage 03371650, North Fork Salt Creek at Nashville, Ind. The hydraulic model was then used to compute 12 water-surface profiles for flood stages at 1-foot (ft) intervals, except for the highest profile of 22.9 ft, referenced to the streamgage datum ranging from 12.0 ft (the NWS “action stage”) to 22.9 ft, which is the highest stage of the current (2015) USGS stage-discharge rating curve and 1.9 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each stage.The availability of these maps, along with information regarding current stage from the USGS streamgage, will provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for postflood recovery efforts.
NASA Astrophysics Data System (ADS)
Pillosu, F. M.; Jurlina, T.; Baugh, C.; Tsonevsky, I.; Hewson, T.; Prates, F.; Pappenberger, F.; Prudhomme, C.
2017-12-01
During hurricane Harvey the greater east Texas area was affected by extensive flash flooding. Their localised nature meant they were too small for conventional large scale flood forecasting systems to capture. We are testing the use of two real time forecast products from the European Centre for Medium-range Weather Forecasts (ECMWF) in combination with local vulnerability information to provide flash flood forecasting tools at the medium range (up to 7 days ahead). Meteorological forecasts are the total precipitation extreme forecast index (EFI), a measure of how the ensemble forecast probability distribution differs from the model-climate distribution for the chosen location, time of year and forecast lead time; and the shift of tails (SOT) which complements the EFI by quantifying how extreme an event could potentially be. Both products give the likelihood of flash flood generating precipitation. For hurricane Harvey, 3-day EFI and SOT products for the period 26th - 29th August 2017 were used, generated from the twice daily, 18 km, 51 ensemble member ECMWF Integrated Forecast System. After regridding to 1 km resolution the forecasts were combined with vulnerable area data to produce a flash flood hazard risk area. The vulnerability data were floodplains (EU Joint Research Centre), road networks (Texas Department of Transport) and urban areas (Census Bureau geographic database), together reflecting the susceptibility to flash floods from the landscape. The flash flood hazard risk area forecasts were verified using a traditional approach against observed National Weather Service flash flood reports, a total of 153 reported flash floods have been detected in that period. Forecasts performed best for SOT = 5 (hit ratio = 65%, false alarm ratio = 44%) and EFI = 0.7 (hit ratio = 74%, false alarm ratio = 45%) at 72 h lead time. By including the vulnerable areas data, our verification results improved by 5-15%, demonstrating the value of vulnerability information within natural hazard forecasts. This research shows that flash flooding from hurricane Harvey was predictable up to 4 days ahead and that filtering the forecasts to vulnerable areas provides a more focused guidance to civil protection agencies planning their emergency response.
Fifty-year flood-inundation maps for Siguatepeque, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Siguatepeque that would be inundated by 50-year floods on Rio Selguapa, Rio Guique, Rio Celan, Rio Calan, and Quebrada Chalantuma. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Siguatepeque as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for 50-year-floods on each of the streams studied were computed using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and ground surveys at six bridges. There are no nearby long-term stream-gaging stations on any of the streams studied; therefore, the 50-year-flood discharges were estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The 50-year-flood discharges estimated for Rio Selguapa, Rio Guique, Rio Celan, Rio Calan, and Quebrada Chalantuma are 323, 168, 161, 146, and 90 cubic meters per second, respectively.
Jones, Joseph L.; Haluska, Tana L.; Kresch, David L.
2001-01-01
A method of updating flood inundation maps at a fraction of the expense of using traditional methods was piloted in Washington State as part of the U.S. Geological Survey Urban Geologic and Hydrologic Hazards Initiative. Large savings in expense may be achieved by building upon previous Flood Insurance Studies and automating the process of flood delineation with a Geographic Information System (GIS); increases in accuracy and detail result from the use of very-high-accuracy elevation data and automated delineation; and the resulting digital data sets contain valuable ancillary information such as flood depth, as well as greatly facilitating map storage and utility. The method consists of creating stage-discharge relations from the archived output of the existing hydraulic model, using these relations to create updated flood stages for recalculated flood discharges, and using a GIS to automate the map generation process. Many of the effective flood maps were created in the late 1970?s and early 1980?s, and suffer from a number of well recognized deficiencies such as out-of-date or inaccurate estimates of discharges for selected recurrence intervals, changes in basin characteristics, and relatively low quality elevation data used for flood delineation. FEMA estimates that 45 percent of effective maps are over 10 years old (FEMA, 1997). Consequently, Congress has mandated the updating and periodic review of existing maps, which have cost the Nation almost 3 billion (1997) dollars. The need to update maps and the cost of doing so were the primary motivations for piloting a more cost-effective and efficient updating method. New technologies such as Geographic Information Systems and LIDAR (Light Detection and Ranging) elevation mapping are key to improving the efficiency of flood map updating, but they also improve the accuracy, detail, and usefulness of the resulting digital flood maps. GISs produce digital maps without manual estimation of inundated areas between cross sections, and can generate working maps across a broad range of scales, for any selected area, and overlayed with easily updated cultural features. Local governments are aggressively collecting very-high-accuracy elevation data for numerous reasons; this not only lowers the cost and increases accuracy of flood maps, but also inherently boosts the level of community involvement in the mapping process. These elevation data are also ideal for hydraulic modeling, should an existing model be judged inadequate.
Deutsch, Morris; Ruggles, Fred
1974-01-01
Flooding along the Mississippi River and some of its tributaries was detected by the multispectral scanner (MSS) on the Earth Resources Technology Satellite (ERTS-1) on at least three orbits during the spring of 1973. The ERTS data provided the first opportunity for mapping the regional extent of flooding at the time of the imagery. Special optical data processing techniques were used to produce a variety of multispectral color composites enhancing flood-plain details. One of these, a 2-color composite of near infrared bands 6 and 7, was enlarged and registered to 1:250,000-scale topographic maps and used as the basis for preparation of flood image maps. Two specially filtered 3-color composites of MSS bands 5, 6, and 7 and 4, 5, and 7 were prepared to aid in the interpretation of the data. The extent of the flooding was vividly depicted on a single image by 2-color temporal composites produced on the additive-color viewer using band 7 flood data superimposed on pre-flood band 7 images. On May 24, when the floodwaters at St. Louis receded to bankfull stage, imagery was again obtained by ERTS. Analysis of temporal data composites of the pre-flood and post-flood band 7 images indicate that changes in surface reflectance characteristics caused by the flooding can be delineated, thus making it possible to map the overall area flooded without the necessity of a real-time system to track and image the peak flood waves. Regional planning and disaster relief agencies such as the Corps of Engineers, Office of Emergency Preparedness, Soil Conservation Service, interstate river basin commissions and state agencies, as well as private lending and insurance institutions, have indicated strong potential applications for ERTS image-maps of flood-prone areas.
Flood-inundation maps for the White River at Noblesville, Indiana
Martin, Zachary W.
2017-11-02
Digital flood-inundation maps for a 7.5-mile reach of the White River at Noblesville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the White River at Noblesville, Ind., streamgage (USGS station number 03349000). Real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at the same site as the USGS streamgage (NWS site NBLI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current (2016) stage-discharge rating at the USGS streamgage 03349000, White River at Noblesville, Ind., and documented high-water marks from the floods of September 4, 2003, and May 6, 2017. The hydraulic model was then used to compute 15 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum ranging from 10.0 ft (the NWS “action stage”) to 24.0 ft, which is the highest stage interval of the current (2016) USGS stage-discharge rating curve and 2 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each stage.The availability of these maps, along with internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for postflood recovery efforts.
Flood-inundation maps for the Wabash River at Lafayette, Indiana
Kim, Moon H.
2018-05-10
Digital flood-inundation maps for an approximately 4.8-mile reach of the Wabash River at Lafayette, Indiana (Ind.) were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science web site at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 03335500, Wabash River at Lafayette, Ind. Current streamflow conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the internet at https://waterdata.usgs.gov/in/nwis/uv?site_no=03335500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (https://water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many places that are often colocated with USGS streamgages, including the Wabash River at Lafayette, Ind. NWS AHPS-forecast peak-stage information may be used with the maps developed in this study to show predicted areas of flood inundation.For this study, flood profiles were computed for the Wabash River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 03335500, Wabash River at Lafayette, Ind., and high-water marks from the flood of July 2003 (U.S. Army Corps of Engineers [USACE], 2007). The calibrated hydraulic model was then used to determine 23 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system digital elevation model derived from light detection and ranging to delineate the area flooded at each water level. The availability of these maps, along with internet information regarding current stage from the USGS streamgage 03335500, Wabash River at Lafayette, Ind., and forecasted high-flow stages from the NWS AHPS, will provide emergency management personnel and residents with information that is critical for flood-response activities such as evacuations and road closures, and for postflood recovery efforts.
Flood inundation maps for the Wabash River at New Harmony, Indiana
Fowler, Kathleen K.
2016-10-11
Digital flood-inundation maps for a 3.68-mile reach of the Wabash River extending 1.77 miles upstream and 1.91 miles downstream from streamgage 03378500 at New Harmony, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Wabash River at New Harmony, Ind. (station 03378500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NHRI3).Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Wabash River at New Harmony, Ind., streamgage and the documented high-water marks from the flood of April 27–28, 2013. The calibrated hydraulic model was then used to compute 17 water-surface profiles for flood stages at approximately 1-foot intervals referenced to the streamgage datum and ranging from 10.0 feet, or near bankfull, to 25.4 feet, the highest stage of the stage-discharge rating curve used in the model. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging (lidar) data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each water level.The availability of these maps along with Internet information regarding current stage from the USGS streamgage at Wabash River at New Harmony, Ind., and forecasted stream stages from the NWS will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the East Fork White River near Bedford, Indiana
Fowler, Kathleen K.
2014-01-01
Digital flood-inundation maps for an 1.8-mile reach of the East Fork White River near Bedford, Indiana (Ind.) were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selectedwater levels (stages) at USGS streamgage 03371500, East Fork White River near Bedford, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=03371500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages, including the East Fork White River near Bedford, Ind. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the East Fork White River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 03371500, East Fork White River near Bedford, Ind., and documented high-water marks from the flood of June 2008. The calibrated hydraulic model was then used to determine 20 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging (LiDAR) data having a 0.593-foot vertical accuracy) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage near Bedford, Ind., and forecasted stream stages from the NWS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for postflood recovery eforts.
Multi-Hazard Assessment of Scour Damaged Bridges with UAS-Based Measurements
NASA Astrophysics Data System (ADS)
Özcan, O.; Ozcan, O.
2017-12-01
Flood and stream induced scour occurring in bridge piers constructed on rivers is one of the mostly observed failure reasons in bridges. Scour induced failure risk in bridges and determination of the alterations in bridge safety under seismic effects has the ultimate importance. Thus, for the determination of bridge safety under the scour effects, the scour amount under bridge piers should be designated realistically and should be tracked and updated continuously. Hereby, the scour induced failures in bridge foundation systems will be prevented and bridge substructure design will be conducted safely. In this study, in order to measure the amount of scour in bridge load bearing system (pile foundations and pile abutments) and to attain very high definition 3 dimensional models of river flood plain for the flood analysis, unmanned aircraft system (UAS) based measurement methods were implemented. UAS based measurement systems provide new and practical approach and bring high precision and reliable solutions considering recent measurement systems. For this purpose, the reinforced concrete (RC) bridge that is located on Antalya Boğaçayı River, Turkey and that failed in 2003 due to flood-induced scour was selected as the case study. The amount of scour occurred in bridge piers and piles was determined realistically and the behavior of bridge piers under scour effects was investigated. Future flood effects and the resultant amount of scour was determined with HEC-RAS software by using digital surface models that were obtained at regular intervals using UAS for the riverbed. In the light of the attained scour measurements and expected scour after a probable flood event, the behavior of scour damaged RC bridge was investigated by pushover and time history analyses under lateral and vertical seismic loadings. In the analyses, the load and displacement capacity of bridge was observed to diminish significantly under expected scour. Thus, the deterioration in multi hazard performance of the bridge was monitored significantly in the light of updated bridge load bearing system capacity. Regarding the case study, UAS based and continuously updated bridge multi hazard risk detection system was established that can be used for bridges located on riverbed.
Flood-inundation maps for a 6.5-mile reach of the Kentucky River at Frankfort, Kentucky
Lant, Jeremiah G.
2013-01-01
Digital flood-inundation maps for a 6.5-mile reach of Kentucky River at Frankfort, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Frankfort Office of Emergency Management. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage Kentucky River at Lock 4 at Frankfort, Kentucky (station no. 03287500). Current conditions for the USGS streamgage may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis/inventory?agency_code=USGS&site_no=03287500). In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the Kentucky River reach by using HEC–RAS, a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (2013) stage-discharge relation for the Kentucky River at Lock 4 at Frankfort, Kentucky, in combination with streamgage and high-water-mark measurements collected for a flood event in May 2010. The calibrated model was then used to calculate 26 water-surface profiles for a sequence of flood stages, at 1-foot intervals, referenced to the streamgage datum and ranging from a stage near bankfull to the elevation that breached the levees protecting the City of Frankfort. To delineate the flooded area at each interval flood stage, the simulated water-surface profiles were combined with a digital elevation model (DEM) of the study area by using geographic information system software. The DEM consisted of bare-earth elevations within the study area and was derived from a Light Detection And Ranging (LiDAR) dataset having a 5.0-foot horizontal resolution and an accuracy of 0.229 foot. The availability of these maps, along with Internet information regarding current stages from USGS streamgages and forecasted stages from the NWS, provides emergency management personnel and local residents with critical information for flood response activities such as evacuations, road closures, and postflood recovery efforts.
Flood-inundation maps for the Leaf River at Hattiesburg, Mississippi
Storm, John B.
2012-01-01
Digital flood-inundation maps for a 1.7-mile reach of the Leaf River were developed by the U.S. Geological Survey (USGS) in cooperation with the City of Hattiesburg, City of Petal, Forrest County, Mississippi Emergency Management Agency, Mississippi Department of Homeland Security, and the Emergency Management District. The Leaf River study reach extends from just upstream of the U.S. Highway 11 crossing to just downstream of East Hardy/South Main Street and separates the cities of Hattiesburg and Petal, Mississippi. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water-surface elevations (stages) at the USGS streamgage at Leaf River at Hattiesburg, Mississippi (02473000). Current conditions at the USGS streamgage may be obtained through the National Water Information System Web site at http://waterdata.usgs.gov/ms/nwis/uv/?site_no=02473000&PARAmeter_cd=00065,00060. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. The forecasted peak-stage information, available on the AHPS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the Leaf River at Hattiesburg, Mississippi, streamgage and documented high-water marks from recent and historical floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 1.0-foot intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water-surface elevation at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model [derived from Light Detection and Ranging (LiDAR) data having a 0.6-foot vertical accuracy and 9.84-foot horizontal resolution] in order to delineate the area flooded at each 1-foot increment of stream stage. The availability of these maps, when combined with real-time stage information from USGS streamgages and forecasted stream stage from the NWS, provides emergency management personnel and residents with critical information during flood-response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Use of Remote Sensing Products for the SERVIR Project
NASA Technical Reports Server (NTRS)
Policelli, Frederick S.
2010-01-01
The United Nations University (UNU) estimates that floods presently impacts greater than 520 million people per year worldwide, resulting in up to 25,000 annual deaths, extensive homelessness, disaster-induced disease, crop and livestock damage, famine, and other serious harm. Meanwhile, aid agencies such as the International Federation of Red Cross and Red Crescent Societies (IFRC) are increasingly seeking better information concerning flood hazards in order to plan for and help mitigate the effects of damaging floods. There is fertile ground to continue development of better remote sensing and modeling techniques to help manage flood related disasters. Disaster management and humanitarian aid organizations need accurate and timely information for making decisions regarding deployment of relief teams and emergency supplies during major floods. Flood maps based on the use of satellite data have proven extremely valuable to such organizations for identifying the location, extent, and severity of these events. However, despite extraordinary efforts on the part of remote sensing data providers to rapidly deliver such maps, there is typically a delay of several days or even weeks from the on-set of flooding until such maps are available to the disaster management community. This paper summarizes efforts at NASA to address this problem through development of an integrated and automated process of a) flood forecasting b) flood detection, c) satellite data acquisition, d) rapid flood mapping and distribution, and e) validation of flood forecasting and detection products.
NASA Astrophysics Data System (ADS)
Lotsari, Eliisa; House, Kyle; Alho, Petteri; Baker, Victor
2017-04-01
Analyses of the evolutionary trajectories of braided ephemeral channels enable identification of trends, magnitudes and periodicity of the processes that affect the channels. In addition to infrequent great floods, relatively frequent, small discharge events have been shown to be important for the evolution of ephemeral channels. However, evolutionary trajectories have rarely been studied in small ephemeral rivers, that predominantly transport gravel, cobles and boulders. Ephemeral tributary channels typify the Colorado River basin (USA), and two examples are Bronco Creek and Eldorado Canyon. These streams experienced extraordinary great floods in 1971 and 1974 respectively, and they are comparable to each other in both basin size, and climatic conditions. Annual precipitation is less than 50 cm, and the average temperature of each month is above 7°C. More importantly, earlier studies have shown similarities in the hydraulics and geomorphic characteristics of the extraordinary floods, which removed the pre-flood bar and braiding structure from the channels. Thus, these two channels are ideal for comparisons of their evolutionary trajecties. Moreover, the availability of high-resolutions aerial photographs for both channels since 1954 allowed for decadal analyses. Our research has analyzed and compared the long-term evolutionary trajectories of the two ephemeral channels within Colorado River Basin based on series of aerial photos and digital elevation models. (1) We detected the development and adjustment of braiding since the extraordinary floods. The detected parameters include the braiding index, bar area and number, channel area and width, confluence number and density, and the proportion of inactive and active areas. (2) We also analyzed the time required for the ephemeral river system to evolve back to its prior state before the high magnitude floods. Finally, (3) we analyzed whether these temporal changes in channel evolution can reveal new insights as to climatic and environmental conditions for these un-gauged basins.
Flood-inundation maps for Lake Champlain in Vermont and in northern Clinton County, New York
Flynn, Robert H.; Hayes, Laura
2016-06-30
Digital flood-inundation maps for an approximately100-mile length of Lake Champlain in Addison, Chittenden, Franklin, and Grand Isle Counties in Vermont and northern Clinton County in New York were created by the U.S. Geological Survey (USGS) in cooperation with the International Joint Commission (IJC). The flood-inundationmaps, which can be accessed through the International Joint Commission (IJC) Web site at http://www.ijc.org/en_/, depict estimates of the areal extent flooding correspondingto selected water levels (stages) at the USGS lake gage on the Richelieu River (Lake Champlain) at Rouses Point, N.Y. (station number 04295000). In this study, wind and seiche effects (standing oscillating wave with a long wavelength) were not taken into account and the flood-inundation mapsreflect 11 stages (elevations) for Lake Champlain that are static for the study length of the lake. Near-real-time stages at this lake gage, and others on Lake Champlain, may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at the Richelieu River (Lake Champlain) at Rouses Point.Static flood boundary extents were determined for LakeChamplain in Addison, Chittenden, Franklin, and Grand Isle Counties in Vermont and northern Clinton County in New York using recently acquired (2013–2014) lidar (light detection and ranging) and may be referenced to any of the five USGS lake gages on Lake Champlain. Of these five lakgages, USGS lake gage 04295000, Richelieu River (Lake Champlain) at Rouses Point, N.Y., is the only USGS lake gage that is also a National Weather Service prediction location. Flood boundary extents for the Lake Champlain static flood-inundation map corresponding to the May 201 flood(103.2 feet [ft], National Geodetic Vertical Datum [NGVD] 29) were evaluated by comparing these boundary extents against the inundation area extents determined for the May 2011 flood (which incorporated documented high-water marksfrom the flood of May 201) (Bjerklie and others, 2014).A digital elevation model (DEM) was created by USGS, within a geographic information system (GIS), from the recently flown and processed light detection and ranging(lidar) data (2013–2014) in Vermont and the lake shore area of northern Clinton County in New York. The lidar data have a vertical accuracy of 0.3 to 0.6-ft (9.6 to 18.0-centimeters [cm]) and a horizontal resolution of 2.3 to 4.6 ft (0.7 to 1.4 meters). This DEM was used in determining the floodboundary for 11 flood stages at 0.5-ft intervals from 100.0 to104.0 ft (NGVD 29) and 1-ft intervals from 104.0 to 106.0 ft (NGVD 29) as referenced to the USGS lake gage 04295000, Richelieu River (Lake Champlain) at Rouses Point, N.Y. In addition, the May 2011 flood-inundation area for elevation103.20 ft (NGVD 29) (102.77 ft, North American Vertical Datum [NAVD] 88) was determined from this DEM. The May 2011 flood is the highest recorded lake water level (stage)at the Rouses Point, N.Y., lake gage. Flood stages greater than 101.5 ft (NGVD 29) exceed the “major flood stage”as defined by the NationalWeather Service for USGS lake gage 04295000.The availability of these maps, along with Internet information regarding current stage from the USGS lake gage and forecasted high-flow stages from the NationalWeather Service, will provide emergency management personnel and residents with information that is critical for flood responseactivities such as evacuations and road closures, as well as for post-flood recovery eforts.
Hydrological Retrospective of floods and droughts: Case study in the Amazon
NASA Astrophysics Data System (ADS)
Wongchuig Correa, Sly; Cauduro Dias de Paiva, Rodrigo; Carlo Espinoza Villar, Jhan; Collischonn, Walter
2017-04-01
Recent studies have reported an increase in intensity and frequency of hydrological extreme events in many regions of the Amazon basin over last decades, these events such as seasonal floods and droughts have originated a significant impact in human and natural systems. Recently, methodologies such as climatic reanalysis are being developed in order to create a coherent register of climatic systems, thus taking this notion, this research efforts to produce a methodology called Hydrological Retrospective (HR), that essentially simulate large rainfall datasets over hydrological models in order to develop a record over past hydrology, enabling the analysis of past floods and droughts. We developed our methodology on the Amazon basin, thus we used eight large precipitation datasets (more than 30 years) through a large scale hydrological and hydrodynamic model (MGB-IPH), after that HR products were validated against several in situ discharge gauges dispersed throughout Amazon basin, given focus in maximum and minimum events. For better HR results according performance metrics, we performed a forecast skill of HR to detect floods and droughts considering in-situ observations. Furthermore, statistical temporal series trend was performed for intensity of seasonal floods and drought in the whole Amazon basin. Results indicate that better HR represented well most past extreme events registered by in-situ observed data and also showed coherent with many events cited by literature, thus we consider viable to use some large precipitation datasets as climatic reanalysis mainly based on land surface component and datasets based in merged products for represent past regional hydrology and seasonal hydrological extreme events. On the other hand, an increase trend of intensity was realized for maximum annual discharges (related to floods) in north-western regions and for minimum annual discharges (related to drought) in central-south regions of the Amazon basin, these features were previously detected by other researches. In the whole basin, we estimated an upward trend of maximum annual discharges at Amazon River. In order to estimate better future hydrological behavior and their impacts on the society, HR could be used as a methodology to understand past extreme events occurrence in many places considering the global coverage of rainfall datasets.
Flood-inundation maps for the East Fork White River at Shoals, Indiana
Boldt, Justin A.
2016-05-06
Digital flood-inundation maps for a 5.9-mile reach of the East Fork White River at Shoals, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the East Fork White River at Shoals, Ind. (USGS station number 03373500). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS) at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS AHPS site SHLI3). NWS AHPS forecast peak stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation.Flood profiles were computed for the East Fork White River reach by means of a one-dimensional, step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the current stage-discharge relation (USGS rating no. 43.0) at USGS streamgage 03373500, East Fork White River at Shoals, Ind. The calibrated hydraulic model was then used to compute 26 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from approximately bankfull (10 ft) to the highest stage of the current stage-discharge rating curve (35 ft). The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM), derived from light detection and ranging (lidar) data, to delineate the area flooded at each water level. The areal extent of the 24-ft flood-inundation map was verified with photographs from a flood event on July 20, 2015.The availability of these maps, along with information on the Internet regarding current stage from the USGS streamgage at East Fork White River at Shoals, Ind., and forecasted stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
An expanded model: flood-inundation maps for the Leaf River at Hattiesburg, Mississippi, 2013
Storm, John B.
2014-01-01
Digital flood-inundation maps for a 6.8-mile reach of the Leaf River at Hattiesburg, Mississippi (Miss.), were created by the U.S. Geological Survey (USGS) in cooperation with the City of Hattiesburg, City of Petal, Forrest County, Mississippi Emergency Management Agency, Mississippi Department of Homeland Security, and the Emergency Management District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Leaf River at Hattiesburg, Miss. (station no. 02473000). Current conditions for estimating near-real-time areas of inundation by use of USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relations at the Leaf River at Hattiesburg, Miss. streamgage (02473000) and documented high-water marks from recent and historical floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 1.0-foot intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM, derived from light detection and ranging (lidar) data having a 0.6-foot vertical and 9.84-foot horizontal resolution) in order to delineate the area flooded at each water level. Development of the estimated flood inundation maps as described in this report update previously published inundation estimates by including reaches of the Bouie and Leaf Rivers above their confluence. The availability of these maps along with Internet information regarding current stage from USGS streamgages and forecasted stream stages from the NWS provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post flood recovery efforts.
NASA Astrophysics Data System (ADS)
Naulin, Jean-Philippe; Payrastre, Olivier; Gaume, Eric; Delrieu, Guy
2013-04-01
Accurate flood forecasts are crucial for an efficient flood event management. Until now, hydro-meteorological forecasts have been mainly used for early-warnings in France (Meteorological and flood vigilance maps) or over the world (Flash-flood guidances). These forecasts are generally limited to the main streams covered by the flood forecasting services or to specific watersheds with particular assets like check dams which are in most cases well gauged river sections, leaving aside large parts of the territory. A distributed hydro-meteorological forecasting approach will be presented, able to take advantage of the high spatial and temporal resolution rainfall estimates that are now available to provide information at ungauged sites. The proposed system aiming at detecting road inundation risks had been initially developed and tested in areas of limited size. Its extension to a whole region (the Gard region in the South of France) will be presented, including over 2000 crossing points between rivers and roads and its validation against a large data set of actually reported road inundations observed during recent flash-flood events. These first validation results appear promising. Such a tool would provide the necessary information for flood event management services to identify the areas at risk and to take the appropriate safety and rescue measures: pre-positioning of rescue means, stopping of the traffic on exposed roads, determination of safe accesses or evacuation routes. Moreover, beyond the specific application to the supervision of a road network, this work provides also results concerning the performances of hydro-meteorological forecasts for ungauged headwaters.
UAVSAR and TerraSAR-X Based InSAR Detection of Localized Subsidence in the New Orleans Area
NASA Astrophysics Data System (ADS)
Blom, R. G.; An, K.; Jones, C. E.; Latini, D.
2014-12-01
Vulnerability of the US Gulf coast to inundation has received increased attention since hurricanes Katrina and Rita. Compounding effects of sea level rise, wetland loss, and regional and local subsidence makes flood protection a difficult challenge, and particularly for the New Orleans area. Key to flood protection is precise knowledge of elevations and elevation changes. Analysis of historical and continuing geodetic measurements show surprising complexity, including locations subsiding more rapidly than considered during planning of hurricane protection and coastal restoration projects. Combining traditional, precise geodetic data with interferometric synthetic aperture radar (InSAR) observations can provide geographically dense constraints on surface deformation. The Gulf Coast environment is challenging for InSAR techniques, especially with systems not designed for interferometry. We use two InSAR capable systems, the L- band (24 cm wavelength) airborne JPL/NASA UAVSAR, and the DLR/EADS Astrium spaceborne TerraSAR X-band (3 cm wavelength), and compare results. First, we are applying pair-wise InSAR to the longer wavelength UAVSAR data to detect localized elevation changes potentially impacting flood protection infrastructure from 2009 - 2014. We focus on areas on and near flood protection infrastructure to identify changes indicative of subsidence, structural deformation, and/or seepage. The Spaceborne TerraSAR X-band SAR system has relatively frequent observations, and dense persistent scatterers in urban areas, enabling measurement of very small displacements. We compare L-band UAVSAR results with permanent scatterer (PS-InSAR) and Short Baseline Subsets (SBAS) interferometric analyses of a stack composed by 28 TerraSAR X-band images acquired over the same period. Thus we can evaluate results from the different radar frequencies and analyses techniques. Preliminary results indicate subsidence features potentially of a variety of causes, including ground water pumping to post recent construction ground compaction. Our overall goal is to enable incorporation of InSAR into the decision making process via identification and delineation of areas of persistent subsidence, and provide input to improve monitoring and planning in flood risk areas.
NASA Technical Reports Server (NTRS)
Deutschman, W. A. (Principal Investigator)
1973-01-01
The author has identified the following significant results. Detection of short-lived events has continued. Forest fires, oil spills, vegetation damage, volcanoes, storm ridges, earthquakes, and floods have been detected and analyzed.
NASA Astrophysics Data System (ADS)
Ragettli, S.; Zhou, J.; Wang, H.; Liu, C.
2017-12-01
Flash floods in small mountain catchments are one of the most frequent causes of loss of life and property from natural hazards in China. Hydrological models can be a useful tool for the anticipation of these events and the issuing of timely warnings. Since sub-daily streamflow information is unavailable for most small basins in China, one of the main challenges is finding appropriate parameter values for simulating flash floods in ungauged catchments. In this study, we use decision tree learning to explore parameter set transferability between different catchments. For this purpose, the physically-based, semi-distributed rainfall-runoff model PRMS-OMS is set up for 35 catchments in ten Chinese provinces. Hourly data from more than 800 storm runoff events are used to calibrate the model and evaluate the performance of parameter set transfers between catchments. For each catchment, 58 catchment attributes are extracted from several data sets available for whole China. We then use a data mining technique (decision tree learning) to identify catchment similarities that can be related to good transfer performance. Finally, we use the splitting rules of decision trees for finding suitable donor catchments for ungauged target catchments. We show that decision tree learning allows to optimally utilize the information content of available catchment descriptors and outperforms regionalization based on a conventional measure of physiographic-climatic similarity by 15%-20%. Similar performance can be achieved with a regionalization method based on spatial proximity, but decision trees offer flexible rules for selecting suitable donor catchments, not relying on the vicinity of gauged catchments. This flexibility makes the method particularly suitable for implementation in sparsely gauged environments. We evaluate the probability to detect flood events exceeding a given return period, considering measured discharge and PRMS-OMS simulated flows with regionalized parameters. Overall, the probability of detection of an event with a return period of 10 years is 62%. 44% of all 10-year flood peaks can be detected with a timing error of 2 hours or less. These results indicate that the modeling system can provide useful information about the timing and magnitude of flood events at ungauged sites.
First evaluation of the utility of GPM precipitation in global flood monitoring
NASA Astrophysics Data System (ADS)
Wu, H.; Yan, Y.; Gao, Z.
2017-12-01
The Global Flood Monitoring System (GFMS) has been developed and used to provide real-time flood detection and streamflow estimates over the last few years with significant success shown by validation against global flood event data sets and observed streamflow variations (Wu et al., 2014). It has become a tool for various national and international organizations to appraise flood conditions in various areas, including where rainfall and hydrology information is limited. The GFMS has been using the TRMM Multi-satellite Precipitation Analysis (TMPA) as its main rainfall input. Now, with the advent of the Global Precipitation Measurement (GPM) mission there is an opportunity to significantly improve global flood monitoring and forecasting. GPM's Integrated Multi-satellitE Retrievals for GPM (IMERG) multi-satellite product is designed to take advantage of various technical advances in the field and combine that with an efficient processing system producing "early" (4 hrs) and "late" (12 hrs) products for operational use. Specifically, this study is focused on (1) understanding the difference between the new IMERG products and other existing satellite precipitation products, e.g., TMPA, CMORPH, and ground observations; (2) addressing the challenge in the usage of the IMERG for flood monitoring through hydrologic models, given that only a short period of precipitation data record has been accumulated since the lunch of GPM in 2014; and (3) comparing the statistics of flood simulation based on the DRIVE model with IMERG, TMPA, CMORPH etc. as precipitation inputs respectively. Derivation of a global threshold map is a necessary step to define flood events out of modelling results, which requires a relatively longer historic information. A set of sensitivity tests are conducted by adjusting IMERG's light, moderate, heavy rain to existing precipitation products with long-term records separately, to optimize the strategy of PDF matching. Other aspects are also examined, including higher latitude events, where GPM precipitation algorithms should also provide improvements. This study provides a first evaluating the utility of the new IMERG products in flood monitoring through hydrologic modeling at a global scale.
Fifty-year flood-inundation maps for Sonaguera, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Sonaguera that would be inundated by a 50-year flood of Rio Sonaguera and its tributary, Rio Juan Lazaro. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Sonaguera as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for an estimated 50-year-flood on Rio Sonaguera and Rio Juan Lazaro at Sonaguera were determined using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and a ground survey at the bridge. There are no nearby long-term stream-gaging stations on Rio Sonaguera or Rio Juan Lazaro; therefore, the 50-year-flood discharge for Rio Sonaguera above the confluence with Rio Juan Lazaro, 194 cubic meters per second; for Rio Juan Lazaro at its mouth, 168 cubic meters per second, and for Rio Sonaguera at the downstream end of the study area, 282 cubic meters per second; were estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation.
Detection and Mapping of the Geomorphic Effects of Flooding Using UAV Photogrammetry
NASA Astrophysics Data System (ADS)
Langhammer, Jakub; Vacková, Tereza
2018-04-01
In this paper, we present a novel technique for the objective detection of the geomorphological effects of flooding in riverbeds and floodplains using imagery acquired by unmanned aerial vehicles (UAVs, also known as drones) equipped with an panchromatic camera. The proposed method is based on the fusion of the two key data products of UAV photogrammetry, the digital elevation model (DEM), and the orthoimage, as well as derived qualitative information, which together serve as the basis for object-based segmentation and the supervised classification of fluvial forms. The orthoimage is used to calculate textural features, enabling detection of the structural properties of the image area and supporting the differentiation of features with similar spectral responses but different surface structures. The DEM is used to derive a flood depth model and the terrain ruggedness index, supporting the detection of bank erosion. All the newly derived information layers are merged with the orthoimage to form a multi-band data set, which is used for object-based segmentation and the supervised classification of key fluvial forms resulting from flooding, i.e., fresh and old gravel accumulations, sand accumulations, and bank erosion. The method was tested on the effects of a snowmelt flood that occurred in December 2015 in a montane stream in the Sumava Mountains, Czech Republic, Central Europe. A multi-rotor UAV was used to collect images of a 1-km-long and 200-m-wide stretch of meandering stream with fresh traces of fluvial activity. The performed segmentation and classification proved that the fusion of 2D and 3D data with the derived qualitative layers significantly enhanced the reliability of the fluvial form detection process. The assessment accuracy for all of the detected classes exceeded 90%. The proposed technique proved its potential for application in rapid mapping and detection of the geomorphological effects of flooding.
Flood-inundation maps for Cedar Creek at 18th Street at Auburn, Indiana
Fowler, Kathleen K.
2018-02-27
Digital flood-inundation maps for a 1.9-mile reach of Cedar Creek at Auburn, Indiana (Ind.), from the First Street bridge, downstream to the streamgage at 18th Street, then ending approximately 1,100 feet (ft) downstream of the Baltimore and Ohio railroad, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science web site at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on Cedar Creek at 18th Street at Auburn, Ind. (station number 04179520). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, although forecasts of flood hydrographs are not available at this site (ABBI3).Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Cedar Creek at 18th Street at Auburn, Ind. streamgage and the documented high-water marks from the flood of March 11, 2009. The calibrated hydraulic model was then used to compute seven water-surface profiles for flood stages referenced to the streamgage datum and ranging from 7 ft, or near bankfull, to 13 ft, in 1-foot increments. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging [lidar] data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each water level.The availability of these maps, along with internet information regarding current stage from the USGS streamgage at Cedar Creek at 18th Street at Auburn, Ind., and stream information from the National Weather Service, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for postflood recovery efforts.
Flood-inundation maps for the Elkhart River at Goshen, Indiana
Strauch, Kellan R.
2013-01-01
The U.S. Geological Survey (USGS), in cooperation with the Indiana Office of Community and Rural Affairs, created digital flood-inundation maps for an 8.3-mile reach of the Elkhart River at Goshen, Indiana, extending from downstream of the Goshen Dam to downstream from County Road 17. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to nine selected water levels (stages) at the USGS streamgage at Elkhart River at Goshen (station number 04100500). Current conditions for the USGS streamgages in Indiana may be obtained on the Internet at http://waterdata.usgs.gov/. In addition, stream stage data have been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relation at the Elkhart River at Goshen streamgage. The hydraulic model was then used to compute nine water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from approximately bankfull (5 ft) to greater than the highest recorded water level (13 ft). The simulated water-surface profiles were then combined with a geographic information system (GIS) digital-elevation model (DEM), derived from Light Detection and Ranging (LiDAR) data having a 0.37-ft vertical accuracy and 3.9-ft horizontal resolution in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for postflood recovery efforts.
NASA Astrophysics Data System (ADS)
Grossi, Giovanna; Caronna, Paolo; Ranzi, Roberto
2014-05-01
Within the framework of risk communication, the goal of an early warning system is to support the interaction between technicians and authorities (and subsequently population) as a prevention measure. The methodology proposed in the KULTURisk FP7 project aimed to build a closer collaboration between these actors, in the perspective of promoting pro-active actions to mitigate the effects of flood hazards. The transnational (Slovenia/ Italy) Soča/Isonzo case study focused on this concept of cooperation between stakeholders and hydrological forecasters. The DIMOSHONG_VIP hydrological model was calibrated for the Vipava/Vipacco River (650 km2), a tributary of the Soča/Isonzo River, on the basis of flood events occurred between 1998 and 2012. The European Centre for Medium-Range Weather Forecasts (ECMWF) provided the past meteorological forecasts, both deterministic (1 forecast) and probabilistic (51 ensemble members). The resolution of the ECMWF grid is currently about 15 km (Deterministic-DET) and 30 km (Ensemble Prediction System-EPS). A verification was conducted to validate the flood-forecast outputs of the DIMOSHONG_VIP+ECMWF early warning system. Basic descriptive statistics, like event probability, probability of a forecast occurrence and frequency bias were determined. Some performance measures were calculated, such as hit rate (probability of detection) and false alarm rate (probability of false detection). Relative Opening Characteristic (ROC) curves were generated both for deterministic and probabilistic forecasts. These analysis showed a good performance of the early warning system, in respect of the small size of the sample. A particular attention was spent to the design of flood-forecasting output charts, involving and inquiring stakeholders (Alto Adriatico River Basin Authority), hydrology specialists in the field, and common people. Graph types for both forecasted precipitation and discharge were set. Three different risk thresholds were identified ("attention", "pre-alarm" or "alert", "alarm"), with an "icon-style" representation, suitable for communication to civil protection stakeholders or the public. Aiming at showing probabilistic representations in a "user-friendly" way, we opted for the visualization of the single deterministic forecasted hydrograph together with the 5%, 25%, 50%, 75% and 95% percentiles bands of the Hydrological Ensemble Prediction System (HEPS). HEPS is generally used for 3-5 days hydrological forecasts, while the error due to incorrect initial data is comparable to the error due to the lower resolution with respect to the deterministic forecast. In the short term forecasting (12-48 hours) the HEPS-members show obviously a similar tendency; in this case, considering its higher resolution, the deterministic forecast is expected to be more effective. The plot of different forecasts in the same chart allows the use of model outputs from 4/5 days to few hours before a potential flood event. This framework was built to help a stakeholder, like a mayor, a civil protection authority, etc, in the flood control and management operations, and was designed to be included in a wider decision support system.
Assessing the quality of rainfall data when aiming to achieve flood resilience
NASA Astrophysics Data System (ADS)
Hoang, C. T.; Tchiguirinskaia, I.; Schertzer, D.; Lovejoy, S.
2012-04-01
A new EU Floods Directive entered into force five years ago. This Directive requires Member States to coordinate adequate measures to reduce flood risk. European flood management systems require reliable rainfall statistics, e.g. the Intensity-duration-Frequency curves for shorter and shorter durations and for a larger and larger range of return periods. Preliminary studies showed that the number of floods was lower when using low time resolution data of high intensity rainfall events, compared to estimates obtained with the help of higher time resolution data. These facts suggest that a particular attention should be paid to the rainfall data quality in order to adequately investigate flood risk aiming to achieve flood resilience. The potential consequences of changes in measuring and recording techniques have been somewhat discussed in the literature with respect to a possible introduction of artificial inhomogeneities in time series. In this paper, we discuss how to detect another artificiality: most of the rainfall time series have a lower recording frequency than that is assumed, furthermore the effective high-frequency limit often depends on the recording year due to algorithm changes. This question is particularly important for operational hydrology, because an error on the effective recording high frequency introduces biases in the corresponding statistics. In this direction, we developed a first version of a SERQUAL procedure to automatically detect the effective time resolution of highly mixed data. Being applied to the 166 rainfall time series in France, the SERQUAL procedure has detected that most of them have an effective hourly resolution, rather than a 5 minutes resolution. Furthermore, series having an overall 5 minute resolution do not have it for all years. These results raise serious concerns on how to benchmark stochastic rainfall models at a sub-hourly resolution, which are particularly desirable for operational hydrology. Therefore, database quality must be checked before use. Due to the fact that the multiple scales and possible scaling behaviour of hydrological data are particularly important for many applications, including flood resilience research, this paper first investigates the sensitivity of the scaling estimates and methods to the deficit of short duration rainfall data, and consequently propose a few simple criteria for a reliable evaluation of the data quality. Then we showed that our procedure SERQUAL enable us to extract high quality sub-series from longer time series that will be much more reliable to calibrate and/or validate short duration quantiles and hydrological models.
Glacier-induced Hazards in the Trans-Himalaya of Ladakh (NW-India)
NASA Astrophysics Data System (ADS)
Schmidt, Susanne; Dame, Juliane; Nüsser, Marcus
2016-04-01
Glaciers are important water resources for irrigated crop cultivation in the semi-arid Trans-Himalaya of Ladakh (NW-India). Due to global warming, many glaciers of South Asia have retreated over the last century and further ice loss will threaten local livelihoods in the long run. In the short term, an increase of flood events caused by melting glaciers and permafrost is expected for the Himalayan region. Beside large catastrophic events, small outburst floods are 'more' regularly reported for various parts of the region. This also holds true for the Trans-Himalayan region of Ladakh, where small glaciers exist at high altitudes. Caused by glacier retreat, a number of proglacial lakes have been formed, most of them dammed by ice filled moraines. The potential risk of these lakes is shown by recent reports on glacial lake outburst flood in the villages Nidder in October 2010 and Gya in August 2014. The 2014 flood destroyed several agricultural terraces, a new concrete bridge and two houses. Own remote sensing analyses shows the increase of a moraine dammed proglacial lake in the upper catchment area, which grew from about 0.03 to 0.08 km2 between 1969 and 2014. Because of the relatively stable altitude of the lake level, one can assume that the flood was caused by a piping process, initiated by melted ice bodies in the moraine. Already in the 1990s a small GLOF was observed in the village, which destroyed some fields. As in 2014, the lake was not completely spilled and a short-term decrease of the lake area is detectable in remote sensing data. Thus, further GLOF-events can be expected for the future. Beside physical risk factors, population growth and new infrastructure development along the streams and valleys increases potential damages of floods. Therefore, investigations are required to estimate the risks of these small glacial lakes and the potential flood effected area for the case study of Gya as well as for the whole region of Ladakh. Remote sensing data are used to detect glacial lakes and their dynamics, and to derive historical GLOF-events. These results will be contextualized with oral history and local interviews about historical flood events. Due to the small size of these glacial lakes and the fact that many of them are almost always frozen, a monitoring system based on high resolution images and field surveys is required to detect potential lake outburst hazards.
NASA Astrophysics Data System (ADS)
Zhang, W.; Hu, B.; Brown, G.
2018-04-01
The black duck population has decreased significantly due to loss of its breeding habitat. Wetlands are an important feature that relates to habitat management and requires monitoring. Synthetic Aperture Radar (SAR) systems are helpful to map the wetland as the microwave signals are sensitive to water content and can be used to map surface water extent, saturated soils, and flooded vegetation. In this study, RadarSat 2 Polarimetric data is employed to map surface water and track changes in extent over the years through image thresholding and reviewed different approaches of Polarimetric decompositions for detecting flooded vegetation. Also, object-based analysis associated with beaver activity is conducted with combined multispectral SPOT satellite imagery. Results show SAR data has proven ability to improve mapping open water areas and locate flooded vegetation areas.
Code of Federal Regulations, 2010 CFR
2010-10-01
... local flood protection systems no longer provide base flood protection. 65.14 Section 65.14 Emergency... § 65.14 Remapping of areas for which local flood protection systems no longer provide base flood protection. (a) General. (1) This section describes the procedures to follow and the types of information...
Code of Federal Regulations, 2013 CFR
2013-10-01
... local flood protection systems no longer provide base flood protection. 65.14 Section 65.14 Emergency... § 65.14 Remapping of areas for which local flood protection systems no longer provide base flood protection. (a) General. (1) This section describes the procedures to follow and the types of information...
Code of Federal Regulations, 2011 CFR
2011-10-01
... local flood protection systems no longer provide base flood protection. 65.14 Section 65.14 Emergency... § 65.14 Remapping of areas for which local flood protection systems no longer provide base flood protection. (a) General. (1) This section describes the procedures to follow and the types of information...
Uncertainty Comparison of Visual Sensing in Adverse Weather Conditions†
Lo, Shi-Wei; Wu, Jyh-Horng; Chen, Lun-Chi; Tseng, Chien-Hao; Lin, Fang-Pang; Hsu, Ching-Han
2016-01-01
This paper focuses on flood-region detection using monitoring images. However, adverse weather affects the outcome of image segmentation methods. In this paper, we present an experimental comparison of an outdoor visual sensing system using region-growing methods with two different growing rules—namely, GrowCut and RegGro. For each growing rule, several tests on adverse weather and lens-stained scenes were performed, taking into account and analyzing different weather conditions with the outdoor visual sensing system. The influence of several weather conditions was analyzed, highlighting their effect on the outdoor visual sensing system with different growing rules. Furthermore, experimental errors and uncertainties obtained with the growing rules were compared. The segmentation accuracy of flood regions yielded by the GrowCut, RegGro, and hybrid methods was 75%, 85%, and 87.7%, respectively. PMID:27447642
Flood-inundation maps for the Tippecanoe River near Delphi, Indiana
Menke, Chad D.; Bunch, Aubrey R.; Kim, Moon H.
2013-01-01
Digital flood-inundation maps for an 11-mile reach of the Tippecanoe River that extends from County Road W725N to State Road 18 below Oakdale Dam, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at USGS streamgage 03333050, Tippecanoe River near Delphi, Ind. Current conditions at the USGS streamgages in Indiana may be obtained online at http://waterdata.usgs.gov/in/nwis/current/?type=flow. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, water-surface profiles were simulated for the stream reach by means of a hydraulic one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation at USGS streamgage 03333050, Tippecanoe River near Delphi, Ind., and USGS streamgage 03332605, Tippecanoe River below Oakdale Dam, Ind. The hydraulic model was then used to simulate 13 water-surface profiles for flood stages at 1-foot intervals reference to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. A flood inundation map was generated for each water-surface profile stage (13 maps in all) so that, for any given flood stage, users will be able to view the estimated area of inundation. The availability of these maps, along with current stage from USGS streamgages and forecasted stream stages from the NWS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Impact of floods induced by extreme precipitation events on public health
NASA Astrophysics Data System (ADS)
Mavroulis, Spyridon; Mavrouli, Maria; Lekkas, Efthymios; Tsakris, Athanassios
2017-04-01
Hydrometeorological disasters comprise the most reported type of natural disaster, and floods account for the majority of disasters in this category in both developed and developing countries. Flooding can lead to extensive morbidity and mortality and pose multiple risks to public health throughout the world. This study involved an extensive and systematic literature review of 124 research publications related to public health impact of 98 floods that occurred globally (Oceania 4, Africa 9, America 22, Europe 24, Asia 39) from 1942 to 2014. The inclusion criteria were literature type comprising journal articles and official reports, natural disaster type including floods induced after extreme precipitation events (accumulation of rainwater in poorly-drained environments, riverine and flash floods), population type including humans, and outcome measure characterized by infectious diseases (ID) incidence increase. The potential post-flood ID are classified into 13 groups including rodent-borne (reported in 38 of the total 98 events, 38.78%), water-borne (33, 33.67%), vector-borne (25, 25.51%), respiratory (19, 19.39%), fecal-oral (14, 14.29%), skin (9, 9.18%), blood-borne (4, 4.08%), eye (3, 3.06%), soil-related (3, 3.06%), ear (2, 2.04%), fungal (1, 1.02%) and wound-borne (1, 1.02%) ID. Based on available age and genre data, it is concluded that the most vulnerable population groups are predominantly young children (age ≤ 5 years) and male. The most fatal post-flood ID are leptospirosis and diarrhea followed by respiratory tract infections. The detected risk factors include (1) poor economic status and living in flood prone areas, (2) destruction of infrastructures, disruption of public utilities and interruption of basic public health services such as vector control programs, (3) direct physical exposure to sewage-polluted flood water, (4) lack of adequate potable water and water-supply from contaminated ponds and tube wells along with lack of distribution of water purification tablets, (5) aggravation of environmental conditions comprising rapid cooling of the environment and heightened humidity, (6) population displacement resulting in densely populated and overcrowded regions, (7) unfavorable living conditions in emergency shelters (8) improper and inadequate sanitation or no access to clean water and sanitation, (9) proliferation and abrupt increase of vector and rodent populations after flooding, (10) contamination of water, damp soil, mud or vegetation caused by rodent urine, dead animals and overflow of latrines. In conclusion, various ID emerge after the flood onset, and outbreaks may result due to the combined effect of several aggravating socio-economic factors and unfavorable environmental conditions. Because of the increased potential for outbreaks after flooding disasters, enhanced public health services and surveillance systems are necessary for the early detection of emerging diseases and outbreaks, and the targeted intervention for disease control.
Preparing for floods: flood forecasting and early warning
NASA Astrophysics Data System (ADS)
Cloke, Hannah
2016-04-01
Flood forecasting and early warning has continued to stride ahead in strengthening the preparedness phases of disaster risk management, saving lives and property and reducing the overall impact of severe flood events. For example, continental and global scale flood forecasting systems such as the European Flood Awareness System and the Global Flood Awareness System provide early information about upcoming floods in real time to various decisionmakers. Studies have found that there are monetary benefits to implementing these early flood warning systems, and with the science also in place to provide evidence of benefit and hydrometeorological institutional outlooks warming to the use of probabilistic forecasts, the uptake over the last decade has been rapid and sustained. However, there are many further challenges that lie ahead to improve the science supporting flood early warning and to ensure that appropriate decisions are made to maximise flood preparedness.
Olson, Scott A.
2015-01-01
Eighteen high-water marks from Tropical Storm Irene were available along the studied reaches. The discharges in the Tropical Storm Irene HEC–RAS model were adjusted so that the resulting water-surface elevations matched the high-water mark elevations along the study reaches. This allowed for an estimation of the water-surface profile throughout the study area resulting from Tropical Storm Irene. From a comparison of the estimated water-surface profile of Tropical Storm Irene to the water-surface profiles of the 1- and 0.2-percent AEP floods, it was determined that the high-water elevations resulting from Tropical Storm Irene exceeded the estimated 1-percent AEP flood throughout the White River and Tweed River study reaches and exceeded the estimated 0.2-percent AEP flood in 16.7 of the 28.6 study reach miles. The simulated water-surface profiles were then combined with a geographic information system digital elevation model derived from light detection and ranging (lidar) data having a 18.2-centimeter vertical accuracy at the 95-percent confidence level and 1-meter horizontal resolution to delineate the area flooded for each water-surface profile.
An Integrated Urban Flood Analysis System in South Korea
NASA Astrophysics Data System (ADS)
Moon, Young-Il; Kim, Min-Seok; Yoon, Tae-Hyung; Choi, Ji-Hyeok
2017-04-01
Due to climate change and the rapid growth of urbanization, the frequency of concentrated heavy rainfall has caused urban floods. As a result, we studied climate change in Korea and developed an integrated flood analysis system that systematized technology to quantify flood risk and flood forecasting in urban areas. This system supports synthetic decision-making through real-time monitoring and prediction on flash rain or short-term rainfall by using radar and satellite information. As part of the measures to deal with the increase of inland flood damage, we have found it necessary to build a systematic city flood prevention system that systematizes technology to quantify flood risk as well as flood forecast, taking into consideration both inland and river water. This combined inland-river flood analysis system conducts prediction on flash rain or short-term rainfall by using radar and satellite information and performs prompt and accurate prediction on the inland flooded area. In addition, flood forecasts should be accurate and immediate. Accurate flood forecasts signify that the prediction of the watch, warning time and water level is precise. Immediate flood forecasts represent the forecasts lead time which is the time needed to evacuate. Therefore, in this study, in order to apply rainfall-runoff method to medium and small urban stream for flood forecasts, short-term rainfall forecasting using radar is applied to improve immediacy. Finally, it supports synthetic decision-making for prevention of flood disaster through real-time monitoring. Keywords: Urban Flood, Integrated flood analysis system, Rainfall forecasting, Korea Acknowledgments This research was supported by a grant (16AWMP-B066744-04) from Advanced Water Management Research Program (AWMP) funded by Ministry of Land, Infrastructure and Transport of Korean government.
NASA Astrophysics Data System (ADS)
Demir, I.
2013-12-01
Recent developments in web technologies make it easy to manage and visualize large data sets with general public. Novel visualization techniques and dynamic user interfaces allow users to create realistic environments, and interact with data to gain insight from simulations and environmental observations. The floodplain simulation system is a web-based 3D interactive flood simulation environment to create real world flooding scenarios. The simulation systems provides a visually striking platform with realistic terrain information, and water simulation. Students can create and modify predefined scenarios, control environmental parameters, and evaluate flood mitigation techniques. The web-based simulation system provides an environment to children and adults learn about the flooding, flood damage, and effects of development and human activity in the floodplain. The system provides various scenarios customized to fit the age and education level of the users. This presentation provides an overview of the web-based flood simulation system, and demonstrates the capabilities of the system for various flooding and land use scenarios.
Flood-inundation maps for the White River at Spencer, Indiana
Nystrom, Elizabeth A.
2013-01-01
Digital flood-inundation maps for a 5.3-mile reach of the White River at Spencer, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage White River at Spencer, Indiana (sta. no. 03357000). Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/. National Weather Service (NWS)-forecasted peak-stage inforamation may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation at the White River at Spencer, Indiana, streamgage and documented high-water marks from the flood of June 8, 2008. The hydraulic model was then used to compute 20 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from the NWS action stage (9 feet) to the highest rated stage (28 feet) at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps along with Internet information regarding the current stage from the Spencer USGS streamgage and forecasted stream stages from the NWS will provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Implementing the national AIGA flash flood warning system in France
NASA Astrophysics Data System (ADS)
Organde, Didier; Javelle, Pierre; Demargne, Julie; Arnaud, Patrick; Caseri, Angelica; Fine, Jean-Alain; de Saint Aubin, Céline
2015-04-01
The French national hydro-meteorological and flood forecasting centre (SCHAPI) aims to implement a national flash flood warning system to improve flood alerts for small-to-medium (up to 1000 km2) ungauged basins. This system is based on the AIGA method, co-developed by IRSTEA these last 10 years. The method, initially set up for the Mediterranean area, is based on a simple event-based hourly hydrologic distributed model run every 15 minutes (Javelle et al. 2014). The hydrologic model ingests operational radar-gauge rainfall grids from Météo-France at a 1-km² resolution to produce discharges for successive outlets along the river network. Discharges are then compared to regionalized flood quantiles of given return periods and warnings (expressed as the range of the return period estimated in real-time) are provided on a river network map. The main interest of the method is to provide forecasters and emergency services with a synthetic view in real time of the ongoing flood situation, information that is especially critical in ungauged flood prone areas. In its enhanced national version, the hourly event-based distributed model is coupled to a continuous daily rainfall-runoff model which provides baseflow and a soil moisture index (for each 1-km² pixel) at the beginning of the hourly simulation. The rainfall-runoff models were calibrated on a selection of 700 French hydrometric stations with Météo-France radar-gauge reanalysis dataset for the 2002-2006 period. To estimate model parameters for ungauged basins, the 2 hydrologic models were regionalised by testing both regressions (using different catchment attributes, such as catchment area, soil type, and climate characteristic) and spatial proximity techniques (transposing parameters from neighbouring donor catchments), as well as different homogeneous hydrological areas. The most valuable regionalisation method was determined for each model through jack-knife cross-validation. The system performance was then evaluated with contingency criteria (e.g., Critical Success Index, Probability Of Detection, Success Ratio) using operational rainfall radar-gauge products from Météo-France for the 2009-2012 period. The regionalised parameters of the distributed model were finally adjusted for each homogeneous hydrological area to optimize the Heidke skill score (HSS) calculated with three levels of warnings (2-, 10- and 50-year flood quantiles). This work is currently being implemented by the SCHAPI to set up an automated national flash flood warning system by 2016. Planned improvements include developing a unique continuous model to be run at a sub-hourly timestep, discharge assimilation, as well as integrating precipitation forecasts while accounting for the main sources of forecast uncertainty. Javelle, P., Demargne, J., Defrance, D., and Arnaud, P. 2014. Evaluating flash flood warnings at ungauged locations using post-event surveys: a case study with the AIGA warning system. Hydrological Sciences Journal, DOI: 10.1080/02626667.2014.923970
Climate, orography and scale controls on flood frequency in Triveneto (Italy)
NASA Astrophysics Data System (ADS)
Persiano, Simone; Castellarin, Attilio; Salinas, Jose Luis; Domeneghetti, Alessio; Brath, Armando
2016-05-01
The growing concern about the possible effects of climate change on flood frequency regime is leading Authorities to review previously proposed reference procedures for design-flood estimation, such as national flood frequency models. Our study focuses on Triveneto, a broad geographical region in North-eastern Italy. A reference procedure for design flood estimation in Triveneto is available from the Italian NCR research project "VA.PI.", which considered Triveneto as a single homogeneous region and developed a regional model using annual maximum series (AMS) of peak discharges that were collected up to the 1980s by the former Italian Hydrometeorological Service. We consider a very detailed AMS database that we recently compiled for 76 catchments located in Triveneto. All 76 study catchments are characterized in terms of several geomorphologic and climatic descriptors. The objective of our study is threefold: (1) to inspect climatic and scale controls on flood frequency regime; (2) to verify the possible presence of changes in flood frequency regime by looking at changes in time of regional L-moments of annual maximum floods; (3) to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI). Our study leads to the following conclusions: (1) climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found in Europe; (2) a single year characterized by extreme floods can have a remarkable influence on regional flood frequency models and analyses for detecting possible changes in flood frequency regime; (3) no significant change was detected in the flood frequency regime, yet an update of the existing reference procedure for design flood estimation is highly recommended and we propose the RoI approach for properly representing climate and scale controls on flood frequency in Triveneto, which cannot be regarded as a single homogeneous region.
Impacts of extreme flooding on riverbank filtration water quality.
Ascott, M J; Lapworth, D J; Gooddy, D C; Sage, R C; Karapanos, I
2016-06-01
Riverbank filtration schemes form a significant component of public water treatment processes on a global level. Understanding the resilience and water quality recovery of these systems following severe flooding is critical for effective water resources management under potential future climate change. This paper assesses the impact of floodplain inundation on the water quality of a shallow aquifer riverbank filtration system and how water quality recovers following an extreme (1 in 17 year, duration >70 days, 7 day inundation) flood event. During the inundation event, riverbank filtrate water quality is dominated by rapid direct recharge and floodwater infiltration (high fraction of surface water, dissolved organic carbon (DOC) >140% baseline values, >1 log increase in micro-organic contaminants, microbial detects and turbidity, low specific electrical conductivity (SEC) <90% baseline, high dissolved oxygen (DO) >400% baseline). A rapid recovery is observed in water quality with most floodwater impacts only observed for 2-3 weeks after the flooding event and a return to normal groundwater conditions within 6 weeks (lower fraction of surface water, higher SEC, lower DOC, organic and microbial detects, DO). Recovery rates are constrained by the hydrogeological site setting, the abstraction regime and the water quality trends at site boundary conditions. In this case, increased abstraction rates and a high transmissivity aquifer facilitate rapid water quality recoveries, with longer term trends controlled by background river and groundwater qualities. Temporary reductions in abstraction rates appear to slow water quality recoveries. Flexible operating regimes such as the one implemented at this study site are likely to be required if shallow aquifer riverbank filtration systems are to be resilient to future inundation events. Development of a conceptual understanding of hydrochemical boundaries and site hydrogeology through monitoring is required to assess the suitability of a prospective riverbank filtration site. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Pope, K. O.; Sheffner, E. J.; Linthicum, K. J.; Bailey, C. L.; Logan, T. M.; Kasischke, E. S.; Birney, K.; Njogu, A. R.; Roberts, C. R.
1992-01-01
Rift Valley Fever (RVF) is a mosquito-borne virus that affects livestock and humans in Africa. Landsat TM data are shown to be effective in identifying dambos, intermittently flooded areas that are potential mosquite breeding sites, in an area north of Nairobi, Kenya. Positive results were obtained from a limited test of flood detection in dambos with airborne high resolution L, C, and X band multipolarization SAR imagery. L and C bands were effective in detecting flooded dambos, but LHH was by far the best channel for discrimination between flooded and nonflooded sites in both sedge and short-grass environments. This study demonstrates the feasibility of a combined passive and active remote sensing program for monitoring the location and condition of RVF vector habitats, thus making future control of the disease more promising.
NASA Astrophysics Data System (ADS)
Alberto, R. T.; Hernando, P. J. C.; Tagaca, R. C.; Celestino, A. B.; Palado, G. C.; Camaso, E. E.; Damian, G. B.
2017-09-01
Climate change has wide-ranging effects on the environment and socio-economic and related sectors which includes water resources, agriculture and food security, human health, terrestrial ecosystems, coastal zones and biodiversity. Farmers are under pressure to the changing weather and increasing unpredictable water supply. Because of rainfall deficiencies, artificial application of water has been made through irrigation. Irrigation is a basic determinant of agriculture because its inadequacies are the most powerful constraints on the increase of agricultural production. Irrigation networks are permanent and temporary conduits that supply water to agricultural areas from an irrigation source. Detection of irrigation networks using LiDAR DTM, and flood susceptible assessment of irrigation networks could give baseline information on the development and management of sustainable agriculture. Map Gully Depth (MGD) in Whitebox GAT was used to generate the potential irrigation networks. The extracted MGD was overlaid in ArcGIS as guide in the digitization of potential irrigation networks. A flood hazard map was also used to identify the flood susceptible irrigation networks in the study area. The study was assessed through field validation of points which were generated using random sampling method. Results of the study showed that most of the detected irrigation networks have low to moderate susceptibility to flooding while the rest have high susceptibility to flooding which is due to shifting weather. These irrigation networks may cause flood when it overflows that could also bring huge damage to rice and other agricultural areas.
2013-01-01
Background Sonography has become the imaging technique of choice for guiding intraoperative interventions in abdominal surgery. Due to artefacts from residual air content, however, videothoracoscopic and open intraoperative ultrasound-guided thermoablation of lung malignancies are impossible. Lung flooding is a new method that allows complete ultrasound imaging of lungs and their tumours. Methods Fourteen resected tumourous human lung lobes were examined transpleurally with B-mode ultrasound before (in atelectasis) and after lung flooding with isotonic saline solution. In two swine, the left lung was filled with 15 ml/kg isotonic saline solution through the left side of a double-lumen tube. Lung tumours were simulated by transthoracic ultrasound-guided injection of 5 ml of purified bovine serum albumin in glutaraldehyde, centrally into the left lower lung lobe. The rate of tumour detection, the severity of disability caused by residual gas, and sonomorphology of the lungs and tumours were assessed. Results The ex vivo tumour detection rate was 100% in flooded human lung lobes and 43% (6/14) in atelectatic lungs. In all cases of atelectasis, sonographic tumour imaging was impaired by residual gas. Tumours and atelectatic tissue were isoechoic. In 28% of flooded lungs, a little residual gas was observed that did not impair sonographic tumour imaging. In contrast to tumours, flooded lung tissue was hyperechoic, homogeneous, and of fine-grained structure. Because of the bronchial wall three-laminar structure, sonographic differentiation of vessels and bronchi was possible. In all cases, malignant tumours in the flooded lung appeared well-demarcated from the lung parenchyma. Adenocarcinoma, squamous, and large cell carcinomas were hypoechoic. Bronchioloalveolar cell carcinoma was slightly hyperechoic. Transpleural sonography identifies endobronchial tumour growth and bronchial wall destruction. With transthoracic sonography, the flooded animal lung can be completely examined in vivo. There is no residual gas, which interferes with ultrasound. Pulmonary vessels and bronchi are clearly differentiated. Simulated lung lesions can easily be detected inside the lung lobe. Conclusions Lung flooding enables complete lung sonography and tumour detection. We have developed a novel method that efficiently uses ultrasound for guiding intraoperative interventions in open and endoscopic lung surgery. PMID:23841910
Niemoczynski, Michal J.; Watson, Kara M.
2016-10-19
Digital flood-inundation maps for an approximate 7.5-mile reach of the Peckman River in New Jersey, which extends from Verona Lake Dam in the Township of Verona downstream through the Township of Cedar Grove and the Township of Little Falls to the confluence with the Passaic River in the Borough of Woodland Park, were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the probable areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Peckman River at Ozone Avenue at Verona, New Jersey (station number 01389534). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/.Flood profiles were simulated for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at USGS streamgages on the Peckman River at Ozone Avenue at Verona, New Jersey (station number 01389534) and the Peckman River at Little Falls, New Jersey (station number 01389550). The hydraulic model was then used to compute eight water-surface profiles for flood stages at 0.5-foot (ft) intervals ranging from 3.0 ft or near bankfull to 6.5 ft, which is approximately the highest recorded water level during the period of record (1979–2014) at USGS streamgage 01389534, Peckman River at Ozone Avenue at Verona, New Jersey. The simulated water-surface profiles were then combined with a geographic information system digital elevation model derived from light detection and ranging (lidar) data to delineate the area flooded at each water level.The availability of these maps along with Internet information regarding current stage from the USGS streamgage provides emergency management personnel and residents with information, such as estimates of inundation extents, based on water stage, that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the Wabash River at Memorial Bridge at Vincennes, Indiana
Fowler, Kathleen K.; Menke, Chad D.
2017-08-23
Digital flood-inundation maps for a 10.2-mile reach of the Wabash River from Sevenmile Island to 3.7 mile downstream of Memorial Bridge (officially known as Lincoln Memorial Bridge) at Vincennes, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 03343010, Wabash River at Memorial Bridge at Vincennes, Ind. Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site.For this study, flood profiles were computed for the Wabash River reach by means of a one-dimensional stepbackwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 03343010, Wabash River at Memorial Bridge at Vincennes, Ind., and preliminary high-water marks from a high-water event on April 27, 2013. The calibrated hydraulic model was then used to determine 19 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from 10 feet (ft) or near bankfull to 28 ft, the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a Geographic Information System (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar] data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) in order to delineate the area flooded at each water level.The availability of these maps—along with Internet information regarding current stage from the USGS streamgage 03343010, and forecast stream stages from the NWS AHPS—provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Musser, Jonathan W.
2012-01-01
Digital flood-inundation maps for a 6.9-mile reach of Suwanee Creek, from the confluence of Ivy Creek to the Noblin Ridge Drive bridge, were developed by the U.S. Geological Survey (USGS) in cooperation with Gwinnett County, Georgia. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Suwanee Creek at Suwanee, Georgia (02334885). Current stage at this USGS streamgage may be obtained at http://waterdata.usgs.gov/ and can be used in conjunction with these maps to estimate near real-time areas of inundation. The National Weather Service (NWS) is incorporating results from this study into the Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that commonly are collocated at USGS streamgages. The forecasted peak-stage information for the USGS streamgage at Suwanee Creek at Suwanee (02334885), available through the AHPS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. A one-dimensional step-backwater model was developed using the U.S. Army Corps of Engineers HEC-RAS software for Suwanee Creek and was used to compute flood profiles for a 6.9-mile reach of the creek. The model was calibrated using the most current stage-discharge relations at the Suwanee Creek at Suwanee streamgage (02334885). The hydraulic model was then used to determine 19 water-surface profiles for flood stages at the Suwanee Creek streamgage at 0.5-foot intervals referenced to the streamgage. The profiles ranged from just above bankfull stage (7.0 feet) to approximately 1.7 feet above the highest recorded water level at the streamgage (16.0 feet). The simulated water-surface profiles were then combined with a geographic information system digital elevation model - derived from light detection and ranging (LiDAR) data having a 5.0-foot horizontal resolution - to delineate the area flooded for each 0.5-foot increment of stream stage. The availability of these maps, when combined with real-time stage information from USGS streamgages and forecasted stream stage from the NWS, provides emergency management personnel and residents with critical information during flood-response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
New NASA Maps Show Flooding Changes In Aftermath of Hurricane Harvey
2017-09-13
Data from NASA's Soil Moisture Active Passive (SMAP) satellite have been used to create new surface flooding maps of Southeast Texas and the Tennessee Valley following Hurricane Harvey. The SMAP observations detect the proportional cover of surface water within the satellite sensor's field of view. This sequence of images shows changes in the extent of surface flooding from successive five-day SMAP observation composite images. Widespread flooding can be seen in the Houston metropolitan area on Aug. 27 following record rainfall from the Category 4 hurricane, which made landfall on Aug. 25th, 2017 (left image). Flood waters around Houston had substantially receded by Aug. 31 (middle image), while flooding had increased across Louisiana, eastern Arkansas, and western Tennessee as then Tropical Storm Harvey passed over the area. The far right image shows the change in flooded area between Aug. 27 and Aug. 31, with regions showing the most flooding recession depicted in yellow and orange shades and those where flooding had increased depicted in blue shades. The SMAP satellite has a low-frequency (L-band) microwave radiometer with enhanced capabilities for detecting surface water changes in nearly all weather conditions and under low-to-moderate vegetation cover. SMAP provides global coverage with one-to-three-day repeat sampling that is well suited for global monitoring of inland surface water cover dynamics. https://photojournal.jpl.nasa.gov/catalog/PIA21951
Fifty-year flood-inundation maps for Comayagua, Hondura
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Comayagua that would be inundated by 50-year floods on Rio Humuya and Rio Majada. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Comayagua as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for 50-year-floods on Rio Humuya and Rio Majada at Comayagua were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. The 50-year-flood discharge for Rio Humuya at Comayagua, 1,400 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The reasonableness of the regression discharge was evaluated by comparing it with drainage-area-adjusted 50-year-flood discharges estimated for three long-term Rio Humuya stream-gaging stations. The drainage-area-adjusted 50-year-flood discharges estimated from the gage records ranged from 946 to 1,365 cubic meters per second. Because the regression equation discharge agrees closely with the high end of the range of discharges estimated from the gaging-station records, it was used for the hydraulic modeling to ensure that the resulting 50-year-flood water-surface elevations would not be underestimated. The 50-year-flood discharge for Rio Majada at Comayagua (230 cubic meters per second) was estimated using the regression equation because there are no long-term gaging-stations on this river from which to estimate the discharge.
Xu, Kui; Ma, Chao; Lian, Jijian; Bin, Lingling
2014-01-01
Catastrophic flooding resulting from extreme meteorological events has occurred more frequently and drawn great attention in recent years in China. In coastal areas, extreme precipitation and storm tide are both inducing factors of flooding and therefore their joint probability would be critical to determine the flooding risk. The impact of storm tide or changing environment on flooding is ignored or underestimated in the design of drainage systems of today in coastal areas in China. This paper investigates the joint probability of extreme precipitation and storm tide and its change using copula-based models in Fuzhou City. The change point at the year of 1984 detected by Mann-Kendall and Pettitt’s tests divides the extreme precipitation series into two subsequences. For each subsequence the probability of the joint behavior of extreme precipitation and storm tide is estimated by the optimal copula. Results show that the joint probability has increased by more than 300% on average after 1984 (α = 0.05). The design joint return period (RP) of extreme precipitation and storm tide is estimated to propose a design standard for future flooding preparedness. For a combination of extreme precipitation and storm tide, the design joint RP has become smaller than before. It implies that flooding would happen more often after 1984, which corresponds with the observation. The study would facilitate understanding the change of flood risk and proposing the adaption measures for coastal areas under a changing environment. PMID:25310006
Xu, Kui; Ma, Chao; Lian, Jijian; Bin, Lingling
2014-01-01
Catastrophic flooding resulting from extreme meteorological events has occurred more frequently and drawn great attention in recent years in China. In coastal areas, extreme precipitation and storm tide are both inducing factors of flooding and therefore their joint probability would be critical to determine the flooding risk. The impact of storm tide or changing environment on flooding is ignored or underestimated in the design of drainage systems of today in coastal areas in China. This paper investigates the joint probability of extreme precipitation and storm tide and its change using copula-based models in Fuzhou City. The change point at the year of 1984 detected by Mann-Kendall and Pettitt's tests divides the extreme precipitation series into two subsequences. For each subsequence the probability of the joint behavior of extreme precipitation and storm tide is estimated by the optimal copula. Results show that the joint probability has increased by more than 300% on average after 1984 (α = 0.05). The design joint return period (RP) of extreme precipitation and storm tide is estimated to propose a design standard for future flooding preparedness. For a combination of extreme precipitation and storm tide, the design joint RP has become smaller than before. It implies that flooding would happen more often after 1984, which corresponds with the observation. The study would facilitate understanding the change of flood risk and proposing the adaption measures for coastal areas under a changing environment.
NASA Astrophysics Data System (ADS)
Leitão, J. P.; de Sousa, L. M.
2018-06-01
Newly available, more detailed and accurate elevation data sets, such as Digital Elevation Models (DEMs) generated on the basis of imagery from terrestrial LiDAR (Light Detection and Ranging) systems or Unmanned Aerial Vehicles (UAVs), can be used to improve flood-model input data and consequently increase the accuracy of the flood modelling results. This paper presents the first application of the MBlend merging method and assesses the impact of combining different DEMs on flood modelling results. It was demonstrated that different raster merging methods can have different and substantial impacts on these results. In addition to the influence associated with the method used to merge the original DEMs, the magnitude of the impact also depends on (i) the systematic horizontal and vertical differences of the DEMs, and (ii) the orientation between the DEM boundary and the terrain slope. The greater water depth and flow velocity differences between the flood modelling results obtained using the reference DEM and the merged DEMs ranged from -9.845 to 0.002 m, and from 0.003 to 0.024 m s-1 respectively; these differences can have a significant impact on flood hazard estimates. In most of the cases investigated in this study, the differences from the reference DEM results were smaller for the MBlend method than for the results of the two conventional methods. This study highlighted the importance of DEM merging when conducting flood modelling and provided hints on the best DEM merging methods to use.
NASA Astrophysics Data System (ADS)
Matgen, Patrick; Giustarini, Laura; Hostache, Renaud
2012-10-01
This paper introduces an automatic flood mapping application that is hosted on the Grid Processing on Demand (GPOD) Fast Access to Imagery (Faire) environment of the European Space Agency. The main objective of the online application is to deliver operationally flooded areas using both recent and historical acquisitions of SAR data. Having as a short-term target the flooding-related exploitation of data generated by the upcoming ESA SENTINEL-1 SAR mission, the flood mapping application consists of two building blocks: i) a set of query tools for selecting the "crisis image" and the optimal corresponding "reference image" from the G-POD archive and ii) an algorithm for extracting flooded areas via change detection using the previously selected "crisis image" and "reference image". Stakeholders in flood management and service providers are able to log onto the flood mapping application to get support for the retrieval, from the rolling archive, of the most appropriate reference image. Potential users will also be able to apply the implemented flood delineation algorithm. The latter combines histogram thresholding, region growing and change detection as an approach enabling the automatic, objective and reliable flood extent extraction from SAR images. Both algorithms are computationally efficient and operate with minimum data requirements. The case study of the high magnitude flooding event that occurred in July 2007 on the Severn River, UK, and that was observed with a moderateresolution SAR sensor as well as airborne photography highlights the performance of the proposed online application. The flood mapping application on G-POD can be used sporadically, i.e. whenever a major flood event occurs and there is a demand for SAR-based flood extent maps. In the long term, a potential extension of the application could consist in systematically extracting flooded areas from all SAR images acquired on a daily, weekly or monthly basis.
Development of Integrated Flood Analysis System for Improving Flood Mitigation Capabilities in Korea
NASA Astrophysics Data System (ADS)
Moon, Young-Il; Kim, Jong-suk
2016-04-01
Recently, the needs of people are growing for a more safety life and secure homeland from unexpected natural disasters. Flood damages have been recorded every year and those damages are greater than the annual average of 2 trillion won since 2000 in Korea. It has been increased in casualties and property damages due to flooding caused by hydrometeorlogical extremes according to climate change. Although the importance of flooding situation is emerging rapidly, studies related to development of integrated management system for reducing floods are insufficient in Korea. In addition, it is difficult to effectively reduce floods without developing integrated operation system taking into account of sewage pipe network configuration with the river level. Since the floods result in increasing damages to infrastructure, as well as life and property, structural and non-structural measures should be urgently established in order to effectively reduce the flood. Therefore, in this study, we developed an integrated flood analysis system that systematized technology to quantify flood risk and flood forecasting for supporting synthetic decision-making through real-time monitoring and prediction on flash rain or short-term rainfall by using radar and satellite information in Korea. Keywords: Flooding, Integrated flood analysis system, Rainfall forecasting, Korea Acknowledgments This work was carried out with the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ011686022015)" Rural Development Administration, Republic of Korea
Flood inundation maps for the Wabash and Eel Rivers at Logansport, Indiana
Fowler, Kathleen K.
2014-01-01
Digital flood-inundation maps for an 8.3-mile reach of the Wabash River and a 7.6-mile reach of the Eel River at Logansport, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage Wabash River at Logansport, Ind. (sta. no. 03329000) and USGS streamgage Eel River near Logansport, Ind. (sta. no. 03328500). Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgages 03329000, Wabash River at Logansport, Ind., and 03328500, Eel River near Logansport, Ind. The calibrated hydraulic model was then used to determine five water-surface profiles for flood stage at 1-foot intervals referenced to the Wabash River streamgage datum, and four water-surface profiles for flood stages at 1-foot intervals referenced to the Eel River streamgage datum. The stages range from bankfull to approximately the highest stages that have occurred since 1967 when three flood control dams were built upstream of Logansport, Ind. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar] data having a 0.37-foot vertical accuracy and 3.9-foot horizontal resolution) in order to delineate the area flooded at each stage. The availability of these maps, along with information available on the Internet regarding current stages from the USGS streamgages at Logansport, Ind., and forecasted stream stages from the NWS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post flood recovery efforts.
Probabilistic flood warning using grand ensemble weather forecasts
NASA Astrophysics Data System (ADS)
He, Y.; Wetterhall, F.; Cloke, H.; Pappenberger, F.; Wilson, M.; Freer, J.; McGregor, G.
2009-04-01
As the severity of floods increases, possibly due to climate and landuse change, there is urgent need for more effective and reliable warning systems. The incorporation of numerical weather predictions (NWP) into a flood warning system can increase forecast lead times from a few hours to a few days. A single NWP forecast from a single forecast centre, however, is insufficient as it involves considerable non-predictable uncertainties and can lead to a high number of false or missed warnings. An ensemble of weather forecasts from one Ensemble Prediction System (EPS), when used on catchment hydrology, can provide improved early flood warning as some of the uncertainties can be quantified. EPS forecasts from a single weather centre only account for part of the uncertainties originating from initial conditions and stochastic physics. Other sources of uncertainties, including numerical implementations and/or data assimilation, can only be assessed if a grand ensemble of EPSs from different weather centres is used. When various models that produce EPS from different weather centres are aggregated, the probabilistic nature of the ensemble precipitation forecasts can be better retained and accounted for. The availability of twelve global EPSs through the 'THORPEX Interactive Grand Global Ensemble' (TIGGE) offers a new opportunity for the design of an improved probabilistic flood forecasting framework. This work presents a case study using the TIGGE database for flood warning on a meso-scale catchment. The upper reach of the River Severn catchment located in the Midlands Region of England is selected due to its abundant data for investigation and its relatively small size (4062 km2) (compared to the resolution of the NWPs). This choice was deliberate as we hypothesize that the uncertainty in the forcing of smaller catchments cannot be represented by a single EPS with a very limited number of ensemble members, but only through the variance given by a large number ensembles and ensemble system. A coupled atmospheric-hydrologic-hydraulic cascade system driven by the TIGGE ensemble forecasts is set up to study the potential benefits of using the TIGGE database in early flood warning. Physically based and fully distributed LISFLOOD suite of models is selected to simulate discharge and flood inundation consecutively. The results show the TIGGE database is a promising tool to produce forecasts of discharge and flood inundation comparable with the observed discharge and simulated inundation driven by the observed discharge. The spread of discharge forecasts varies from centre to centre, but it is generally large, implying a significant level of uncertainties. Precipitation input uncertainties dominate and propagate through the cascade chain. The current NWPs fall short of representing the spatial variability of precipitation on a comparatively small catchment. This perhaps indicates the need to improve NWPs resolution and/or disaggregation techniques to narrow down the spatial gap between meteorology and hydrology. It is not necessarily true that early flood warning becomes more reliable when more ensemble forecasts are employed. It is difficult to identify the best forecast centre(s), but in general the chance of detecting floods is increased by using the TIGGE database. Only one flood event was studied because most of the TIGGE data became available after October 2007. It is necessary to test the TIGGE ensemble forecasts with other flood events in other catchments with different hydrological and climatic regimes before general conclusions can be made on its robustness and applicability.
Fifty-year flood-inundation maps for Tocoa, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Tocoa that would be inundated by a 50-year flood of Rio Tocoa. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Tocoa as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for an estimated 50-year-flood on Rio Tocoa at Tocoa were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and a ground survey at one bridge. There are no nearby long-term stream-gaging stations on Rio Tocoa; therefore, the 50-year-flood discharge for Rio Tocoa, 552 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The drainage area and mean annual precipitation estimated for Rio Tocoa at Tocoa are 204 square kilometers and 1,987 millimeters, respectively. It was assumed that a portion of the 50-year flood, 200 cubic meters per second, would escape the main channel and flow down a side channel before re-entering the main channel again near the lower end of the study area.
Fifty-year flood-inundation maps for Tegucigalpa, Honduras
Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Tegucigalpa that would be inundated by a 50-year flood of Rio Choluteca, Rio Grande, Rio Guacerique, and Rio Chiquito. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Tegucigalpa as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for an estimated 50-year-flood on Rio Choluteca, Rio Grande, Rio Guacerique, and Rio Chiquito at Tegucigalpa were determined using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and ground surveys at bridges. There are no nearby long-term stream-gaging stations; therefore, the 50-year-flood discharges were estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The estimated 50-year-flood discharge is 922 cubic meters per second at Rio Choluteca at downstream end of the study area boundary, 663 cubic meters per second at the mouth of the Rio Grande, 475 cubic meters per second at the mouth of the Rio Guacerique, and 254 cubic meters per second at the mouth of the Rio Chiquito.
Hot wet spots of Swiss buildings - detecting clusters of flood exposure
NASA Astrophysics Data System (ADS)
Röthlisberger, Veronika; Zischg, Andreas; Keiler, Margreth
2016-04-01
Where are the hotspots of flood exposure in Switzerland? There is no single answer but rather a wide range of findings depending on the databases and methods used. In principle, the analysis of flood exposure is the overlay of two spatial datasets, one on flood hazard and one on assets, e.g. buildings. The presented study aims to test a new developed approach which is based on public available Swiss data. On the hazard side, these are two different types of flood hazard maps each representing a similar return period beyond the dimensioning of structural protection systems. When it comes to assets we use nationwide harmonized data on building, namely a complete dataset of building polygons to which we assign features as volume, residents and monetary value. For the latter we apply findings of multivariate analyses of insurance data. By overlaying building polygons with the flood hazard map we identify the exposed buildings. We analyse the resulting spatial distribution of flood exposure at different levels of scales (local to regional) using administrative units (e.g. municipalities) but also artificial grids with a corresponding size (e.g. 5 000 m). The presentation focuses on the identification of hotspots highlighting the influence of the applied data and methods, e.g. local scan statistics testing intensities within and without potential clusters or log relative exposure surfaces based on kernel intensity estimates. We find a major difference of identified hotspots between absolute values and normalized values of exposure. Whereas the hotspots of flood exposure in absolute figures mirrors the underlying distribution of buildings, the hotspots of flood exposure ratios show very different pictures. We conclude that findings on flood exposure vary depending on the data and moreover the methods used and therefore need to be communicated carefully and appropriate to different stakeholders who may use the information for decision making on flood risk management.
Main flood peaks in the medieval Carpathian Basin (1000-1500): Annual and decadal overview
NASA Astrophysics Data System (ADS)
Kiss, Andrea
2013-04-01
The analysis of over 140 reported floods is mainly based on contemporary legal evidence (charters), partly on other types of contemporary documentary evidence. Majority of sources contains data on individual flood events (i.e. occurrence, seasonality, magnitude). Concerning main flood peaks, evidence on annual and multi-annual (decadal, multi-decadal) level is also available. Despite data increase in the 13th century, only in the 14th-15th centuries documentation is representative enough to draw further conclusions. Apart from secondary flood peaks (probably in the mid-13th century and the turn of the 13th-14th centuries), three main periods with high flood frequencies are detected: 1330s-1350s, 1390s-1430s, and the late 1480s-1490s (continuing in the early 16th century). The first major flood peak was primarily reported in the eastern Carpathian Basin (the Tisa catchment), and can be characterised by a number of high-intensity flood events (with 1342-1343 in centre). During the second major, prolonged flood peak of 1390s-1430s, and that of the third, late 15th century one the importance of floods occurred on the Danube and in the Danube catchment area has to be as well highlighted. Moreover, in the first half of the 15th century long-term hydrological problems (prolonged high water-level and high flood frequency problems) can be identified. In some cases high flood-frequency periods were accompanied by documented hydromorphological impacts and some impacts on society can be also detected. Results show good agreement with the decadal precipitation reconstruction based on speleothem investigations carried out in North-Hungary.
A Semantic Sensor Web for Environmental Decision Support Applications
Gray, Alasdair J. G.; Sadler, Jason; Kit, Oles; Kyzirakos, Kostis; Karpathiotakis, Manos; Calbimonte, Jean-Paul; Page, Kevin; García-Castro, Raúl; Frazer, Alex; Galpin, Ixent; Fernandes, Alvaro A. A.; Paton, Norman W.; Corcho, Oscar; Koubarakis, Manolis; De Roure, David; Martinez, Kirk; Gómez-Pérez, Asunción
2011-01-01
Sensing devices are increasingly being deployed to monitor the physical world around us. One class of application for which sensor data is pertinent is environmental decision support systems, e.g., flood emergency response. For these applications, the sensor readings need to be put in context by integrating them with other sources of data about the surrounding environment. Traditional systems for predicting and detecting floods rely on methods that need significant human resources. In this paper we describe a semantic sensor web architecture for integrating multiple heterogeneous datasets, including live and historic sensor data, databases, and map layers. The architecture provides mechanisms for discovering datasets, defining integrated views over them, continuously receiving data in real-time, and visualising on screen and interacting with the data. Our approach makes extensive use of web service standards for querying and accessing data, and semantic technologies to discover and integrate datasets. We demonstrate the use of our semantic sensor web architecture in the context of a flood response planning web application that uses data from sensor networks monitoring the sea-state around the coast of England. PMID:22164110
Identifying Changes of Complex Flood Dynamics with Recurrence Analysis
NASA Astrophysics Data System (ADS)
Wendi, D.; Merz, B.; Marwan, N.
2016-12-01
Temporal changes in flood hazard system are known to be difficult to detect and attribute due to multiple drivers that include complex processes that are non-stationary and highly variable. These drivers, such as human-induced climate change, natural climate variability, implementation of flood defense, river training, or land use change, could impact variably on space-time scales and influence or mask each other. Flood time series may show complex behavior that vary at a range of time scales and may cluster in time. Moreover hydrological time series (i.e. discharge) are often subject to measurement errors, such as rating curve error especially in the case of extremes where observation are actually derived through extrapolation. This study focuses on the application of recurrence based data analysis techniques (recurrence plot) for understanding and quantifying spatio-temporal changes in flood hazard in Germany. The recurrence plot is known as an effective tool to visualize the dynamics of phase space trajectories i.e. constructed from a time series by using an embedding dimension and a time delay, and it is known to be effective in analyzing non-stationary and non-linear time series. Sensitivity of the common measurement errors and noise on recurrence analysis will also be analyzed and evaluated against conventional methods. The emphasis will be on the identification of characteristic recurrence properties that could associate typical dynamic to certain flood events.
Fuel cell flooding detection and correction
DiPierno Bosco, Andrew; Fronk, Matthew Howard
2000-08-15
Method and apparatus for monitoring an H.sub.2 -O.sub.2 PEM fuel cells to detect and correct flooding. The pressure drop across a given H.sub.2 or O.sub.2 flow field is monitored and compared to predetermined thresholds of unacceptability. If the pressure drop exists a threshold of unacceptability corrective measures are automatically initiated.
USDA-ARS?s Scientific Manuscript database
Pesticides are frequently detected in rivers, lakes and groundwater sources in regions where rice is cultivated in Brazil. The transport of these compounds to water sources is strongly related to the irrigation system adopted in paddy fields. However, information on the dissipation of clomazone, ima...
Pluvial, urban flood mechanisms and characteristics - Assessment based on insurance claims
NASA Astrophysics Data System (ADS)
Sörensen, Johanna; Mobini, Shifteh
2017-12-01
Pluvial flooding is a problem in many cities and for city planning purpose the mechanisms behind pluvial flooding are of interest. Previous studies seldom use insurance claim data to analyse city scale characteristics that lead to flooding. In the present study, two long time series (∼20 years) of flood claims from property owners have been collected and analysed in detail to investigate the mechanisms and characteristics leading to urban flooding. The flood claim data come from the municipal water utility company and property owners with insurance that covers property loss from overland flooding, groundwater intrusion through basement walls and flooding from the drainage system. These data are used as a proxy for flood severity for several events in the Swedish city of Malmö. It is discussed which rainfall characteristics give most flooding and why some rainfall events do not lead to severe flooding, how city scale topography and sewerage system type influence spatial distribution of flood claims, and which impact high sea level has on flooding in Malmö. Three severe flood events are described in detail and compared with a number of smaller flood events. It was found that the main mechanisms and characteristics of flood extent and its spatial distribution in Malmö are intensity and spatial distribution of rainfall, distance to the main sewer system as well as overland flow paths, and type of drainage system, while high sea level has little impact on the flood extent. Finally, measures that could be taken to lower the flood risk in Malmö, and other cities with similar characteristics, are discussed.
Novel Flood Detection and Analysis Method Using Recurrence Property
NASA Astrophysics Data System (ADS)
Wendi, Dadiyorto; Merz, Bruno; Marwan, Norbert
2016-04-01
Temporal changes in flood hazard are known to be difficult to detect and attribute due to multiple drivers that include processes that are non-stationary and highly variable. These drivers, such as human-induced climate change, natural climate variability, implementation of flood defence, river training, or land use change, could impact variably on space-time scales and influence or mask each other. Flood time series may show complex behavior that vary at a range of time scales and may cluster in time. This study focuses on the application of recurrence based data analysis techniques (recurrence plot) for understanding and quantifying spatio-temporal changes in flood hazard in Germany. The recurrence plot is known as an effective tool to visualize the dynamics of phase space trajectories i.e. constructed from a time series by using an embedding dimension and a time delay, and it is known to be effective in analyzing non-stationary and non-linear time series. The emphasis will be on the identification of characteristic recurrence properties that could associate typical dynamic behavior to certain flood situations.
Rapid Disaster Analysis based on Remote Sensing: A Case Study about the Tohoku Tsunami Disaster 2011
NASA Astrophysics Data System (ADS)
Yang, C. H.; Soergel, U.; Lanaras, Ch.; Baltsavias, E.; Cho, K.; Remondino, F.; Wakabayashi, H.
2014-09-01
In this study, we present first results of RAPIDMAP, a project funded by European Union in a framework aiming to foster the cooperation of European countries with Japan in R&D. The main objective of RAPIDMAP is to construct a Decision Support System (DSS) based on remote sensing data and WebGIS technologies, where users can easily access real-time information assisting with disaster analysis. In this paper, we present a case study of the Tohoku Tsunami Disaster 2011. We address two approaches namely change detection based on SAR data and co-registration of optical and SAR satellite images. With respect to SAR data, our efforts are subdivided into three parts: (1) initial coarse change detection for entire area, (2) flood area detection, and (3) linearfeature change detection. The investigations are based on pre- and post-event TerraSAR-X images. In (1), two pre- and post-event TerraSAR-X images are accurately co-registered and radiometrically calibrated. Data are fused in a false-color image that provides a quick and rough overview of potential changes, which is useful for initial decision making and identifying areas worthwhile to be analysed further in more depth. However, a bunch of inevitable false alarms appear within the scene caused by speckle, temporal decorrelation, co-registration inaccuracy and so on. In (2), the post-event TerraSAR-X data are used to extract the flood area by using thresholding and morphological approaches. The validated result indicates that using SAR data combining with suitable morphological approaches is a quick and effective way to detect flood area. Except for usage of SAR data, the false-color image composed of optical images are also used to detect flood area for further exploration in this part. In (3), Curvelet filtering is applied in the difference image of pre- and post-event TerraSAR-X images not only to suppress false alarms of irregular-features, but also to enhance the change signals of linear-features (e.g. buildings) in settlements. Afterwards, thresholding is exploited to extract the linear-feature changes. In rapid mapping of disasters various sensors are often employed, including optical and SAR, since they provide complementary information. Such data needs to be analyzed in an integrated fashion and the results from each dataset should be integrated in a GIS with a common coordinate reference system. Thus, if no orthoimages can be generated, the images should be co-registered employing matching of common features. We present results of co-registration between optical (FORMOSAT-2) and TerraSAR-X images based on different matching methods, and also techniques for detecting and eliminating matching errors.
Fifty-year flood-inundation maps for Choluteca, Honduras
Kresch, David L.; Mastin, Mark C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Choluteca that would be inundated by 50-year floods on Rio Choluteca and Rio Iztoca. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Choluteca as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for 50-year-floods on Rio Choluteca and Rio Iztoca at Choluteca were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. The estimated 50-year-flood discharge for Rio Choluteca at Choluteca is 4,620 cubic meters per second, which is the drainage-area-adjusted weighted-average of two independently estimated 50-year-flood discharges for the gaging station Rio Choluteca en Puente Choluteca. One discharge, 4,913 cubic meters per second, was estimated from a frequency analysis of the 17 years of peak discharge record for the gage, and the other, 2,650 cubic meters per second, was estimated from a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The weighted-average of the two discharges at the gage is 4,530 cubic meters per second. The 50-year-flood discharge for the study area reach of Rio Choluteca was estimated by multiplying the weighted discharge at the gage by the ratio of the drainage areas upstream from the two locations. The 50-year-flood discharge for Rio Iztoca, which was estimated from the regression equation, is 430 cubic meters per second.
Flood-inundation maps for the Iroquois River at Rensselaer, Indiana
Fowler, Kathleen K.; Bunch, Aubrey R.
2013-01-01
Digital flood-inundation maps for a 4.0-mile reach of the Iroquois River at Rensselaer, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 05522500, Iroquois River at Rensselaer, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at (http://waterdata.usgs.gov/in/nwis/uv?site_no=05522500). In addition, the National Weather Service (NWS) forecasts flood hydrographs at the Rensselaer streamgage. That forecasted peak-stage information, also available on the Internet (http://water.weather.gov/ahps/), may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the Iroquois River reach by means of a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (June 27, 2012) stage-discharge relations at USGS streamgage 05522500, Iroquois River at Rensselaer, Ind., and high-water marks from the flood of July 2003. The calibrated hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at Rensselaer, Ind., and forecasted stream stages from the NWS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the White River at Newberry, Indiana
Fowler, Kathleen K.; Kim, Moon H.; Menke, Chad D.
2012-01-01
Digital flood-inundation maps for a 4.9-mile reach of the White River at Newberry, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at USGS streamgage 03360500, White River at Newberry, Ind. Current conditions at the USGS streamgage may be obtained on the Internet (http://waterdata.usgs.gov/in/nwis/uv?site_no=03360500). The National Weather Service (NWS) forecasts flood hydrographs at the Newberry streamgage. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the White River reach by means of a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current stage-discharge relation at USGS streamgage 03360500, White River at Newberry, Ind., and high-water marks from a flood in June 2008.The calibrated hydraulic model was then used to determine 22 water-surface profiles for flood stages a1-foot intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at Newberry, Ind., and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post-flood recovery efforts.
NASA Astrophysics Data System (ADS)
Moon, Young-Il; Kim, Jong-Suk
2015-04-01
Due to rapid urbanization and climate change, the frequency of concentrated heavy rainfall has increased, causing urban floods that result in casualties and property damage. As a consequence of natural disasters that occur annually, the cost of damage in Korea is estimated to be over two billion US dollars per year. As interest in natural disasters increase, demands for a safe national territory and efficient emergency plans are on the rise. In addition to this, as a part of the measures to cope with the increase of inland flood damage, it is necessary to build a systematic city flood prevention system that uses technology to quantify flood risk as well as flood forecast based on both rivers and inland water bodies. Despite the investment and efforts to prevent landside flood damage, research and studies of landside-river combined hydro-system is at its initial stage in Korea. Therefore, the purpose of this research introduces the causes of flood damage in Seoul and shows a flood forecasting and warning system in urban streams of Seoul. This urban flood forecasting and warning system conducts prediction on flash rain or short-term rainfall by using radar and satellite information and performs prompt and accurate prediction on the inland flooded area and also supports synthetic decision-making for prevention through real-time monitoring. Although we cannot prevent damage from typhoons or localized heavy rain, we can minimize that damage with accurate and timely forecast and a prevention system. To this end, we developed a flood forecasting and warning system, so in case of an emergency there is enough time for evacuation and disaster control. Keywords: urban flooding, flood risk, inland-river system, Korea Acknowledgments This research was supported by a grant (13AWMP-B066744-01) from Advanced Water Management Research Program (AWMP) funded by Ministry of Land, Infrastructure and Transport of Korean government.
Field Testing of Energy-Efficient Flood-Damage-Resistant Residential Envelope Systems Summary Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aglan, H.
2005-08-04
The primary purpose of the project was to identify materials and methods that will make the envelope of a house flood damage resistant. Flood damage resistant materials and systems are intended to be used to repair houses subsequent to flooding. This project was also intended to develop methods of restoring the envelopes of houses that have been flooded but are repairable and may be subject to future flooding. Then if the house floods again, damage will not be as extensive as in previous flood events and restoration costs and efforts will be minimized. The purpose of the first pair ofmore » field tests was to establish a baseline for typical current residential construction practice. The first test modules used materials and systems that were commonly found in residential envelopes throughout the U.S. The purpose of the second pair of field tests was to begin evaluating potential residential envelope materials and systems that were projected to be more flood-damage resistant and restorable than the conventional materials and systems tested in the first pair of tests. The purpose of testing the third slab-on-grade module was to attempt to dry flood proof the module (no floodwater within the structure). If the module could be sealed well enough to prevent water from entering, then this would be an effective method of making the interior materials and systems flood damage resistant. The third crawl space module was tested in the same manner as the previous modules and provided an opportunity to do flood tests of additional residential materials and systems. Another purpose of the project was to develop the methodology to collect representative, measured, reproducible (i.e. scientific) data on how various residential materials and systems respond to flooding conditions so that future recommendations for repairing flood damaged houses could be based on scientific data. An additional benefit of collecting this data is that it will be used in the development of a standard test procedure which could lead to the certification of building materials and systems as flood damage resistant.« less
Dynamic building risk assessment theoretic model for rainstorm-flood utilization ABM and ABS
NASA Astrophysics Data System (ADS)
Lai, Wenze; Li, Wenbo; Wang, Hailei; Huang, Yingliang; Wu, Xuelian; Sun, Bingyun
2015-12-01
Flood is one of natural disasters with the worst loss in the world. It needs to assess flood disaster risk so that we can reduce the loss of flood disaster. Disaster management practical work needs the dynamic risk results of building. Rainstorm flood disaster system is a typical complex system. From the view of complex system theory, flood disaster risk is the interaction result of hazard effect objects, rainstorm flood hazard factors, and hazard environments. Agent-based modeling (ABM) is an important tool for complex system modeling. Rainstorm-flood building risk dynamic assessment method (RFBRDAM) was proposed using ABM in this paper. The interior structures and procedures of different agents in proposed meth had been designed. On the Netlogo platform, the proposed method was implemented to assess the building risk changes of the rainstorm flood disaster in the Huaihe River Basin using Agent-based simulation (ABS). The results indicated that the proposed method can dynamically assess building risk of the whole process for the rainstorm flood disaster. The results of this paper can provide one new approach for flood disaster building risk dynamic assessment and flood disaster management.
Flood Damage and Loss Estimation for Iowa on Web-based Systems using HAZUS
NASA Astrophysics Data System (ADS)
Yildirim, E.; Sermet, M. Y.; Demir, I.
2016-12-01
Importance of decision support systems for flood emergency response and loss estimation increases with its social and economic impacts. To estimate the damage of the flood, there are several software systems available to researchers and decision makers. HAZUS-MH is one of the most widely used desktop program, developed by FEMA (Federal Emergency Management Agency), to estimate economic loss and social impacts of disasters such as earthquake, hurricane and flooding (riverine and coastal). HAZUS used loss estimation methodology and implements through geographic information system (GIS). HAZUS contains structural, demographic, and vehicle information across United States. Thus, it allows decision makers to understand and predict possible casualties and damage of the floods by running flood simulations through GIS application. However, it doesn't represent real time conditions because of using static data. To close this gap, an overview of a web-based infrastructure coupling HAZUS and real time data provided by IFIS (Iowa Flood Information System) is presented by this research. IFIS is developed by the Iowa Flood Center, and a one-stop web-platform to access community-based flood conditions, forecasts, visualizations, inundation maps and flood-related data, information, and applications. Large volume of real-time observational data from a variety of sensors and remote sensing resources (radars, rain gauges, stream sensors, etc.) and flood inundation models are staged on a user-friendly maps environment that is accessible to the general public. Providing cross sectional analyses between HAZUS-MH and IFIS datasets, emergency managers are able to evaluate flood damage during flood events easier and more accessible in real time conditions. With matching data from HAZUS-MH census tract layer and IFC gauges, economical effects of flooding can be observed and evaluated by decision makers. The system will also provide visualization of the data by using augmented reality for see-through displays. Emergency management experts can take advantage of this visualization mode to manage flood response activities in real time. Also, forecast system developed by the Iowa Flood Center will be used to predict probable damage of the flood.
Flood and Landslide Applications of Near Real-time Satellite Rainfall Products
NASA Technical Reports Server (NTRS)
Hong, Yang; Adler, Robert F.; Negri, Andrew; Huffman, George J.
2007-01-01
Floods and associated landslides are one of the most widespread natural hazards on Earth, responsible for tens of thousands of deaths and billions of dollars in property damage every year. During 1993-2002, over 1000 of the more than 2,900 natural disasters reported were due to floods. These floods and associated landslides claimed over 90,000 lives, affected over 1.4 billion people and cost about $210 billion. The impact of these disasters is often felt most acutely in less developed regions. In many countries around the world, satellite-based precipitation estimation may be the best source of rainfall data due to lack of surface observing networks. Satellite observations can be of essential value in improving our understanding of the occurrence of hazardous events and possibly in lessening their impact on local economies and in reducing injuries, if they can be used to create reliable warning systems in cost-effective ways. This article addressed these opportunities and challenges by describing a combination of satellite-based real-time precipitation estimation with land surface characteristics as input, with empirical and numerical models to map potential of landslides and floods. In this article, a framework to detect floods and landslides related to heavy rain events in near-real-time is proposed. Key components of the framework are: a fine resolution precipitation acquisition system; a comprehensive land surface database; a hydrological modeling component; and landslide and debris flow model components. A key precipitation input dataset for the integrated applications is the NASA TRMM-based multi-satellite precipitation estimates. This dataset provides near real-time precipitation at a spatial-temporal resolution of 3 hours and 0.25deg x 0.25deg. By careful integration of remote sensing and in-situ observations, and assimilation of these observations into hydrological and landslide/debris flow models with surface topographic information, prediction of useful probabilistic maps of landslide and floods for emergency management in a timely manner is possible. Early results shows that the potential exists for successful application of satellite precipitation data in improving/developing global monitoring systems for flood/landslide disaster preparedness and management. The scientific and technological prototype can be first applied in a representative test-bed and then the information deliverables for the region can be tailored to the societal and economic needs of the represented affected countries.
Landslide and Flood Warning System Prototypes based on Wireless Sensor Networks
NASA Astrophysics Data System (ADS)
Hloupis, George; Stavrakas, Ilias; Triantis, Dimos
2010-05-01
Wireless sensor networks (WSNs) are one of the emerging areas that received great attention during the last few years. This is mainly due to the fact that WSNs have provided scientists with the capability of developing real-time monitoring systems equipped with sensors based on Micro-Electro-Mechanical Systems (MEMS). WSNs have great potential for many applications in environmental monitoring since the sensor nodes that comprised from can host several MEMS sensors (such as temperature, humidity, inertial, pressure, strain-gauge) and transducers (such as position, velocity, acceleration, vibration). The resulting devices are small and inexpensive but with limited memory and computing resources. Each sensor node contains a sensing module which along with an RF transceiver. The communication is broadcast-based since the network topology can change rapidly due to node failures [1]. Sensor nodes can transmit their measurements to central servers through gateway nodes without any processing or they make preliminary calculations locally in order to produce results that will be sent to central servers [2]. Based on the above characteristics, two prototypes using WSNs are presented in this paper: A Landslide detection system and a Flood warning system. Both systems sent their data to central processing server where the core of processing routines exists. Transmission is made using Zigbee and IEEE 802.11b protocol but is capable to use VSAT communication also. Landslide detection system uses structured network topology. Each measuring node comprises of a columnar module that is half buried to the area under investigation. Each sensing module contains a geophone, an inclinometer and a set of strain gauges. Data transmitted to central processing server where possible landslide evolution is monitored. Flood detection system uses unstructured network topology since the failure rate of sensor nodes is expected higher. Each sensing module contains a custom water level sensor (based on plastic optical fiber). Data transmitted directly to server where the early warning algorithms monitor the water level variations in real time. Both sensor nodes use power harvesting techniques in order to extend their battery life as much as possible. [1] Yick J.; Mukherjee, B.; Ghosal, D. Wireless sensor network survey. Comput. Netw. 2008, 52, 2292-2330. [2] Garcia, M.; Bri, D.; Boronat, F.; Lloret, J. A new neighbor selection strategy for group-based wireless sensor networks, In The Fourth International Conference on Networking and Services (ICNS 2008), Gosier, Guadalupe, March 16-21, 2008.
Boudaghpour, Siamak; Bagheri, Majid; Bagheri, Zahra
2014-01-01
High flood occurrences with large environmental damages have a growing trend in Iran. Dynamic movements of water during a flood cause different environmental damages in geographical areas with different characteristics such as topographic conditions. In general, environmental effects and damages caused by a flood in an area can be investigated from different points of view. The current essay is aiming at detecting environmental effects of flood occurrences in Halilrood catchment area of Kerman province in Iran using flood zone mapping techniques. The intended flood zone map was introduced in four steps. Steps 1 to 3 pave the way to calculate and estimate flood zone map in the understudy area while step 4 determines the estimation of environmental effects of flood occurrence. Based on our studies, wide range of accuracy for estimating the environmental effects of flood occurrence was introduced by using of flood zone mapping techniques. Moreover, it was identified that the existence of Jiroft dam in the study area can decrease flood zone from 260 hectares to 225 hectares and also it can decrease 20% of flood peak intensity. As a result, 14% of flood zone in the study area can be saved environmentally.
A dimension reduction method for flood compensation operation of multi-reservoir system
NASA Astrophysics Data System (ADS)
Jia, B.; Wu, S.; Fan, Z.
2017-12-01
Multiple reservoirs cooperation compensation operations coping with uncontrolled flood play vital role in real-time flood mitigation. This paper come up with a reservoir flood compensation operation index (ResFCOI), which formed by elements of flood control storage, flood inflow volume, flood transmission time and cooperation operations period, then establish a flood cooperation compensation operations model of multi-reservoir system, according to the ResFCOI to determine a computational order of each reservoir, and lastly the differential evolution algorithm is implemented for computing single reservoir flood compensation optimization in turn, so that a dimension reduction method is formed to reduce computational complexity. Shiguan River Basin with two large reservoirs and an extensive uncontrolled flood area, is used as a case study, results show that (a) reservoirs' flood discharges and the uncontrolled flood are superimposed at Jiangjiaji Station, while the formed flood peak flow is as small as possible; (b) cooperation compensation operations slightly increase in usage of flood storage capacity in reservoirs, when comparing to rule-based operations; (c) it takes 50 seconds in average when computing a cooperation compensation operations scheme. The dimension reduction method to guide flood compensation operations of multi-reservoir system, can make each reservoir adjust its flood discharge strategy dynamically according to the uncontrolled flood magnitude and pattern, so as to mitigate the downstream flood disaster.
iFLOOD: A Real Time Flood Forecast System for Total Water Modeling in the National Capital Region
NASA Astrophysics Data System (ADS)
Sumi, S. J.; Ferreira, C.
2017-12-01
Extreme flood events are the costliest natural hazards impacting the US and frequently cause extensive damages to infrastructure, disruption to economy and loss of lives. In 2016, Hurricane Matthew brought severe damage to South Carolina and demonstrated the importance of accurate flood hazard predictions that requires the integration of riverine and coastal model forecasts for total water prediction in coastal and tidal areas. The National Weather Service (NWS) and the National Ocean Service (NOS) provide flood forecasts for almost the entire US, still there are service-gap areas in tidal regions where no official flood forecast is available. The National capital region is vulnerable to multi-flood hazards including high flows from annual inland precipitation events and surge driven coastal inundation along the tidal Potomac River. Predicting flood levels on such tidal areas in river-estuarine zone is extremely challenging. The main objective of this study is to develop the next generation of flood forecast systems capable of providing accurate and timely information to support emergency management and response in areas impacted by multi-flood hazards. This forecast system is capable of simulating flood levels in the Potomac and Anacostia River incorporating the effects of riverine flooding from the upstream basins, urban storm water and tidal oscillations from the Chesapeake Bay. Flood forecast models developed so far have been using riverine data to simulate water levels for Potomac River. Therefore, the idea is to use forecasted storm surge data from a coastal model as boundary condition of this system. Final output of this validated model will capture the water behavior in river-estuary transition zone far better than the one with riverine data only. The challenge for this iFLOOD forecast system is to understand the complex dynamics of multi-flood hazards caused by storm surges, riverine flow, tidal oscillation and urban storm water. Automated system simulations will help to develop a seamless integration with the boundary systems in the service-gap area with new insights into our scientific understanding of such complex systems. A visualization system is being developed to allow stake holders and the community to have access to the flood forecasting for their region with sufficient lead time.
Coupling flood forecasting and social media crowdsourcing
NASA Astrophysics Data System (ADS)
Kalas, Milan; Kliment, Tomas; Salamon, Peter
2016-04-01
Social and mainstream media monitoring is being more and more recognized as valuable source of information in disaster management and response. The information on ongoing disasters could be detected in very short time and the social media can bring additional information to traditional data feeds (ground, remote observation schemes). Probably the biggest attempt to use the social media in the crisis management was the activation of the Digital Humanitarian Network by the United Nations Office for the Coordination of Humanitarian Affairs in response to Typhoon Yolanda. The network of volunteers performing rapid needs & damage assessment by tagging reports posted to social media which were then used by machine learning classifiers as a training set to automatically identify tweets referring to both urgent needs and offers of help. In this work we will present the potential of coupling a social media streaming and news monitoring application ( GlobalFloodNews - www.globalfloodsystem.com) with a flood forecasting system (www.globalfloods.eu) and the geo-catalogue of the OGC services discovered in the Google Search Engine (WMS, WFS, WCS, etc.) to provide a full suite of information available to crisis management centers as fast as possible. In GlobalFloodNews we use advanced filtering of the real-time Twitter stream, where the relevant information is automatically extracted using natural language and signal processing techniques. The keyword filters are adjusted and optimized automatically using machine learning algorithms as new reports are added to the system. In order to refine the search results the forecasting system will be triggering an event-based search on the social media and OGC services relevant for crisis response (population distribution, critical infrastructure, hospitals etc.). The current version of the system makes use of USHAHIDI Crowdmap platform, which is designed to easily crowdsource information using multiple channels, including SMS, email, Twitter and the web we want to show the potential of monitoring floods at the global scale.
NASA Astrophysics Data System (ADS)
Zhang, B.; Wdowinski, S.; Oliver-Cabrera, T.; Koirala, R.; Jo, M. J.; Osmanoglu, B.
2018-04-01
During Hurricane Irma's passage over Florida in September 2017, many sections of the state experienced heavy rain and sequent flooding. In order to drain water out of potential flooding zones and assess property damage, it is important to map the extent and magnitude of the flooded areas at various stages of the storm. We use Synthetic Aperture Radar (SAR) and Interferometric SAR (InSAR) observations, acquired by Sentinel-1 before, during and after the hurricane passage, which enable us to evaluate surface condition during different stages of the hurricane. This study uses multi-temporal images acquired under dry condition before the hurricane to constrain the background backscattering signature. Flooded areas are detected when the backscattering during the hurricane is statistically significantly different from the average dry conditions. The detected changes can be either an increase or decrease of the backscattering, which depends on the scattering characteristics of the surface. In addition, water level change information in Palmdale, South Florida is extracted from an interferogram with the aid of a local water gauge as the reference. The results of our flooding analysis revealed that the majority of the study area in South Florida was flooded during Hurricane Irma.
Street floods in Metro Manila and possible solutions.
Lagmay, Alfredo Mahar; Mendoza, Jerico; Cipriano, Fatima; Delmendo, Patricia Anne; Lacsamana, Micah Nieves; Moises, Marc Anthony; Pellejera, Nicanor; Punay, Kenneth Niño; Sabio, Glenn; Santos, Laurize; Serrano, Jonathan; Taniza, Herbert James; Tingin, Neil Eneri
2017-09-01
Urban floods from thunderstorms cause severe problems in Metro Manila due to road traffic. Using Light Detection and Ranging (LiDAR)-derived topography, flood simulations and anecdotal reports, the root of surface flood problems in Metro Manila is identified. Majority of flood-prone areas are along the intersection of creeks and streets located in topographic lows. When creeks overflow or when rapidly accumulated street flood does not drain fast enough to the nearest stream channel, the intersecting road also gets flooded. Possible solutions include the elevation of roads or construction of well-designed drainage structures leading to the creeks. Proposed solutions to the flood problem of Metro Manila may avoid paralyzing traffic problems due to short-lived rain events, which according to Japan International Cooperation Agency (JICA) cost the Philippine economy 2.4billionpesos/day. Copyright © 2017. Published by Elsevier B.V.
Fifty-year flood-inundation maps for Juticalpa, Honduras
Kresch, David L.; Mastin, M.C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Juticalpa that would be inundated by a 50-year flood of Rio Juticalpa. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Juticalpa as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for a 50-year-flood on Rio Juticalpa at Juticalpa were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. The estimated 50-year-flood discharge for Rio Juticalpa at Juticalpa, 1,360 cubic meters per second, was computed as the drainage-area-adjusted weighted average of two independently estimated 50-year-flood discharges for the gaging station Rio Juticalpa en El Torito, located about 2 kilometers upstream from Juticalpa. One discharge, 1,551 cubic meters per second, was estimated from a frequency analysis of the 33 years of peak-discharge record for the gage, and the other, 486 cubic meters per second, was estimated from a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The weighted-average of the two discharges at the gage is 1,310 cubic meters per second. The 50-year flood discharge for the study area reach of Rio Juticalpa was estimated by multiplying the weighted discharge at the gage by the ratio of the drainage areas upstream from the two locations.
NASA Astrophysics Data System (ADS)
Adler, R. F.; Wu, H.
2016-12-01
The Global Flood Monitoring System (GFMS) (http://flood.umd.edu) has been developed and used in recent years to provide real-time flood detection, streamflow estimates and inundation calculations for most of the globe. The GFMS is driven by satellite-based precipitation, with the accuracy of the flood estimates being primarily dependent on the accuracy of the precipitation analyses and the land surface and routing models used. The routing calculations are done at both 12 km and 1 km resolution. Users of GFMS results include international and national flood response organizations. The devastating floods in October 2015 in South Carolina are analyzed indicating that the GFMS estimated streamflow is accurate and useful indicating significant flooding in the upstream basins. Further downstream the GFMS streamflow underestimates due to the presence of dams which are not accounted for in GFMS. Other examples are given for Yemen and Somalia and for Sri Lanka and southern India. A forecast flood event associated with a typhoon hitting Taiwan is also examined. One-kilometer resolution inundation mapping from GFMS holds the promise of highly useful information for flood disaster response. The algorithm is briefly described and examples are shown for recent cases where inundation estimates available from optical and Synthetic Aperture Radar (SAR) satellite sensors are available. For a case of significant flooding in Texas in May and June along the Brazos River the GFMS calculated streamflow compares favorably with the observed. Available Landsat-based (May 28) and MODIS-based (June 2) inundation analyses from U. of Colorado shows generally good agreement with the GFMS inundation calculation in most of the area where skies were clear and the optical techniques could be applied. The GFMS provides very useful disaster response information on a timely basis. However, there is still significant room for improvement, including improved precipitation information from NASA's Global Precipitation Measurement (GPM) mission, inclusion of dam algorithms in the routing model and integration with or assimilation of observed flood extent from satellite optical and SAR sensors.
Healthy riparian ecosystems in arid and semi-arid regions exhibit shifting patterns of vegetation in response to periodic flooding. Their conditions also depend upon the amount of grazing and other human uses. Taking advantage of these system properties, we developed and tested a...
NASA Astrophysics Data System (ADS)
Cabello, Angels; Velasco, Marc; Escaler, Isabel
2010-05-01
Floods, including flash floods and debris flow events, are one of the most important hazards in Europe regarding both economic and life loss. Moreover, changes in precipitation patterns and intensity are very likely to increase due to the observed and predicted global warming, rising the risk in areas that are already vulnerable to floods. Therefore, it is very important to carry out new strategies to improve flood protection, but it is also crucial to take into account historical data to identify high risk areas. The main objective of this paper is to show a comparative analysis of the flood risk management information compiled in four test-bed basins (Llobregat, Guadalhorce, Gardon d'Anduze and Linth basins) from three different European countries (Spain, France and Switzerland) and to identify which are the lessons learnt from their past experiences in order to propose future strategies on risk management. This work is part of the EU 7th FP project IMPRINTS which aims at reducing loss of life and economic damage through the improvement of the preparedness and the operational risk management of flash flood and debris flow (FF & DF) events. The methodology followed includes the following steps: o Specific survey on the effectivity of the implemented emergency plans and risk management procedures sent to the test-bed basin authorities that participate in the project o Analysis of the answers from the questionnaire and further research on their methodologies for risk evaluation o Compilation of available follow-up studies carried out after major flood events in the four test-bed basins analyzed o Collection of the lessons learnt through a comparative analysis of the previous information o Recommendations for future strategies on risk management based on lessons learnt and management gaps detected through the process As the Floods Directive (FD) already states, the flood risks associated to FF & DF events should be assessed through the elaboration of Flood Risk Management Plans (FRMP) with tailored solutions for each basin, evaluating their flood mitigation potential, promoting environmental objectives and increasing the efficiency of the already adopted measures. The FRMP should focus on prevention (and protection), preparedness and response, and these have been the three main risk management phases of a flood crisis that have been assessed when extracting the lessons learnt from past events. Lessons learnt concerning dissemination through the three previously mentioned phases and also related to education initiatives have also been included. A common response to most of the events described in this paper was to upgrade the meteorological and hydrological forecasting systems, making the forecasting lead-time as large as possible. Another common recommendation from the test-beds was the need to implement and accomplish the land use regulations. All the basins also detected that structural measures are necessary to increase the population's protection level, but replacing the traditional safety mentality by a risk culture based on a comprehensive analysis of the flood risk. The four basins studied have also highlighted the importance of collecting information when FF & DF events occur and creating historic databases that will provide extremely useful information in the future.
NASA Astrophysics Data System (ADS)
Shim, J. B.; Won, C. Y.; Park, J.; Lee, K.
2017-12-01
Korea experiences frequent flood disasters, which cause considerable economic losses and damages to towns and farms. Especially, a regional torrential storm is about 98.5mm/hr on September 21, 2010 in Seoul. The storm exceeds the capacity of urban drainage system of 75mm/hr, and 9,419 houses. How to monitor and control the urban flood disasters is an important issue in Korea. To mitigate the flood damage, a customizing system was developed to estimate urban floods and inundation using by integrating drainage system data and river information database which are managed by local governments and national agencies. In the case of Korean urban city, there are a lot of detention ponds and drainage pumping stations on end of drainage system and flow is going into river. The drainage pumping station, it is very important hydraulic facility for flood control between river and drainage system. So, it is possible to occur different patterns of flood inundation according to operation rule of drainage pumping station. A flood disaster is different damage as how to operate drainage pumping station and plan operation rule.
Welch, Heather L.; Coupe, Richard H.; Aulenbach, Brent T.
2014-01-01
High streamflow associated with the April–July 2011 Mississippi River flood forced the simultaneous opening of the three major flood-control structures in the lower Mississippi-Atchafalaya River subbasin for the first time in history in order to manage the amount of water moving through the system. The U.S. Geological Survey (USGS) collected samples for analysis of field properties, suspended-sediment concentration, particle-size, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, and up to 136 pesticides at 11 water-quality stations and 2 flood-control structures in the lower Mississippi-Atchafalaya River subbasin from just above the confluence of the upper Mississippi and Ohio Rivers downstream from April through July 2011. Monthly fluxes of suspended sediment, suspended sand, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, simazine, metolachlor, and acetochlor were estimated at 9 stations and 2 flood-control structures during the flood period. Although concentrations during the 2011 flood were within the range of what has been observed historically, concentrations decreased during peak streamflow on the lower Mississippi River. Prior to the 2011 flood, high concentrations of suspended sediment and nitrate were observed in March 2011 at stations downstream of the confluence of the upper Mississippi and Ohio Rivers, which probably resulted in a loss of available material for movement during the flood. In addition, the major contributor of streamflow to the lower Mississippi-Atchafalaya River subbasin during April and May was the Ohio River, whose water contained lower concentrations of suspended sediment, pesticides, and nutrients than water from the upper Mississippi River. Estimated fluxes for the 4-month flood period were still quite high and contributed approximately 50 percent of the estimated annual suspended sediment, nitrate, and total phosphorus fluxes in 2011; the largest fluxes were estimated at the water-quality station located at Vicksburg, Mississippi. The majority of the suspended-sediment flux introduce into the lower Mississippi-Atchafalaya River subbasin during the 2011 flood was in the form of fine-grained particles from the upper Mississippi River—77 percent of the suspended-sediment flux compared to 23 percent from the Ohio River. As water moved downstream along the lower Mississippi River, there were losses in suspended-sediment flux because of deposition and backwater areas. Fluxes showed a greater response to increased streamflow in the Atchafalaya River than in the lower Mississippi River. The result was a gain in suspended-sediment flux with distance downstream in the Atchafalaya River because of resuspension of previously deposited materials—particularly sand particles. Overall, 13 percent less suspended sediment left the lower Mississippi-Atchafalaya River subbasin than entered it from the confluence of the upper Mississippi and Ohio Rivers during the flood. The loss in suspended-sediment flux during the flood accounted for 14 percent of the 2011 annual suspended-sediment flux loss within the lower Mississippi-Atchafalaya River subbasin. Nitrate composed approximately 70 percent of the total nitrogen flux at all of the sampled water-quality stations, excluding the Arkansas River. Almost 2.4 times more nitrate flux entered the lower Mississippi-Atchafalaya River subbasin from the upper Mississippi River than from the Ohio River. As nitrate moved down the lower Mississippi River and the Atchafalaya River, there were no substantial losses or gains in flux, indicating that nitrate moved conservatively within the subbasin during the 2011 flood. Although streamflow was the largest on record, nitrate flux during the flood period resulted in a zone of hypoxia in the Gulf of Mexico that was only the tenth largest on record. The flux of total phosphorus in the lower Mississippi-Atchafalaya River subbasin during the 2011 flood was strongly related to suspended-sediment flux at most of the stations. There were significant gains in total phosphorus flux in the Atchafalaya River during the flood period and losses between the stations along the lower Mississippi River. Overall, however, the amount of total phosphorus flux that left the lower Mississippi-Atchafalaya River subbasin was only 1.7 percent less than the flux that entered it from the upper Mississippi River and the Ohio River, indicating that total phosphorus flux within the subbasin during the flood was conservative. As streamflow was decreasing within the lower Mississippi-Atchafalaya River subbasin, orthophosphate composed an increasing percentage of the total phosphorus concentration, probably because of the return of waters low in oxygen concentration from areas such as inundated lands, backwater streams, and floodways. Poorly oxygenated waters promote the release of sediment-bound phosphorus into the more-readily available dissolved form (measured as orthophosphate in this study). Because of processing within the subbasin during the flood period, there was a 25-percent gain in orthophosphate flux between the confluence of the upper Mississippi and Ohio Rivers and the outlet of the subbasin. Of the 136 pesticide compounds and degradates that were analyzed, only 18 were detected above the method reporting level. The 18 compounds that were detected fell into three categories: (1) compounds that were frequently detected and showed a response in concentration to the flood; (2) compounds that were detected in almost every sample at every station but at low concentrations; and (3) compounds that were infrequently detected. Fluxes for the most frequently detected pesticides having the highest concentrations (atrazine, metolachlor, acetochlor, and simazine) were within the low-to-middle range of historic fluxes. An average of 66,450 cubic feet per second of streamflow was diverted from the lower Mississippi River through the Morganza Floodway into the Atchafalaya River from May 14 through July 7, 2011. Dissolved oxygen concentrations in the floodway decreased with the amount of time that the flood control structure was open, which affected nitrate and orthophosphate concentrations. As dissolved oxygen concentrations decreased in the floodway, nitrate concentrations decreased and orthophosphate concentrations increased. Oil and gas samples were also collected at 1 station upstream and 1 station downstream from the outlet of the Morganza Floodway into the Atchafalaya River. There were no detections of petroleum hydrocarbons in the upstream or downstream samples. All concentrations of oil and grease were relatively low, and the effect of water from the floodway on water quality in the Atchafalaya River could not be determined because oil and grease samples were not collected from the floodway.
Distillation Column Flooding Predictor
DOE Office of Scientific and Technical Information (OSTI.GOV)
George E. Dzyacky
2010-11-23
The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillationmore » columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid/vapor traffic that produce increased contact area and lead to substantial increases in separation efficiency – which translates to a 10% increase in energy efficiency on a BTU/bbl basis. The Flooding Predictor™ operates on the principle that between five to sixty minutes in advance of a flooding event, certain column variables experience an oscillation, a pre-flood pattern. The pattern recognition system of the Flooding Predictor™ utilizes the mathematical first derivative of certain column variables to identify the column’s pre-flood pattern(s). This pattern is a very brief, highly repeatable, simultaneous movement among the derivative values of certain column variables. While all column variables experience negligible random noise generated from the natural frequency of the process, subtle pre-flood patterns are revealed among sub-sets of the derivative values of column variables as the column approaches its hydraulic limit. The sub-set of column variables that comprise the pre-flood pattern is identified empirically through in a two-step process. First, 2ndpoint’s proprietary off-line analysis tool is used to mine historical data for pre-flood patterns. Second, the column is flood-tested to fine-tune the pattern recognition for commissioning. Then the Flooding Predictor™ is implemented as closed-loop advanced control strategy on the plant’s distributed control system (DCS), thus automating control of the column at its hydraulic limit.« less
Evaluation of satellite rainfall estimates for drought and flood monitoring in Mozambique
Tote, Carolien; Patricio, Domingos; Boogaard, Hendrik; van der Wijngaart, Raymond; Tarnavsky, Elena; Funk, Christopher C.
2015-01-01
Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and floods and thus, an understanding of the strengths and weaknesses of different rainfall products is valuable. Three dekadal (10-day) gridded satellite rainfall products (TAMSAT African Rainfall Climatology And Time-series (TARCAT) v2.0, Famine Early Warning System NETwork (FEWS NET) Rainfall Estimate (RFE) v2.0, and Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS)) are compared to independent gauge data (2001–2012). This is done using pairwise comparison statistics to evaluate the performance in estimating rainfall amounts and categorical statistics to assess rain-detection capabilities. The analysis was performed for different rainfall categories, over the seasonal cycle and for regions dominated by different weather systems. Overall, satellite products overestimate low and underestimate high dekadal rainfall values. The RFE and CHIRPS products perform as good, generally outperforming TARCAT on the majority of statistical measures of skill. TARCAT detects best the relative frequency of rainfall events, while RFE underestimates and CHIRPS overestimates the rainfall events frequency. Differences in products performance disappear with higher rainfall and all products achieve better results during the wet season. During the cyclone season, CHIRPS shows the best results, while RFE outperforms the other products for lower dekadal rainfall. Products blending thermal infrared and passive microwave imagery perform better than infrared only products and particularly when meteorological patterns are more complex, such as over the coastal, central and south regions of Mozambique, where precipitation is influenced by frontal systems.
Fews-Risk: A step towards risk-based flood forecasting
NASA Astrophysics Data System (ADS)
Bachmann, Daniel; Eilander, Dirk; de Leeuw, Annemargreet; Diermanse, Ferdinand; Weerts, Albrecht; de Bruijn, Karin; Beckers, Joost; Boelee, Leonore; Brown, Emma; Hazlewood, Caroline
2015-04-01
Operational flood prediction and the assessment of flood risk are important components of flood management. Currently, the model-based prediction of discharge and/or water level in a river is common practice for operational flood forecasting. Based on the prediction of these values decisions about specific emergency measures are made within operational flood management. However, the information provided for decision support is restricted to pure hydrological or hydraulic aspects of a flood. Information about weak sections within the flood defences, flood prone areas and assets at risk in the protected areas are rarely used in a model-based flood forecasting system. This information is often available for strategic planning, but is not in an appropriate format for operational purposes. The idea of FEWS-Risk is the extension of existing flood forecasting systems with elements of strategic flood risk analysis, such as probabilistic failure analysis, two dimensional flood spreading simulation and the analysis of flood impacts and consequences. Thus, additional information is provided to the decision makers, such as: • Location, timing and probability of failure of defined sections of the flood defence line; • Flood spreading, extent and hydraulic values in the hinterland caused by an overflow or a breach flow • Impacts and consequences in case of flooding in the protected areas, such as injuries or casualties and/or damages to critical infrastructure or economy. In contrast with purely hydraulic-based operational information, these additional data focus upon decision support for answering crucial questions within an operational flood forecasting framework, such as: • Where should I reinforce my flood defence system? • What type of action can I take to mend a weak spot in my flood defences? • What are the consequences of a breach? • Which areas should I evacuate first? This presentation outlines the additional required workflows towards risk-based flood forecasting systems. In a cooperation between HR Wallingford and Deltares, the extended workflows are being integrated into the Delft-FEWS software system. Delft-FEWS provides modules for managing the data handling and forecasting process. Results of a pilot study that demonstrates the new tools are presented. The value of the newly generated information for decision support during a flood event is discussed.
The framework of a UAS-aided flash flood modeling system for coastal regions
NASA Astrophysics Data System (ADS)
Zhang, H.; Xu, H.
2016-02-01
Flash floods cause severe economic damage and are one of the leading causes of fatalities connected with natural disasters in the Gulf Coast region. Current flash flood modeling systems rely on empirical hydrological models driven by precipitation estimates only. Although precipitation is the driving factor for flash floods, soil moisture, urban drainage system and impervious surface have been recognized to have significant impacts on the development of flash floods. We propose a new flash flooding modeling system that integrates 3-D hydrological simulation with satellite and multi-UAS observations. It will have three advantages over existing modeling systems. First, it will incorporate 1-km soil moisture data through integrating satellite images from European SMOS mission and NASA's SMAP mission. The utilization of high-resolution satellite images will provide essential information to determine antecedent soil moisture condition, which is an essential control on flood generation. Second, this system is able to adjust flood forecasting based on real-time inundation information collected by multi-UAS. A group of UAS will be deployed during storm events to capture the changing extent of flooded areas and water depth at multiple critical locations simultaneously. Such information will be transmitted to a hydrological model to validate and improve flood simulation. Third, the backbone of this system is a state-of-the-art 3-D hydrological model that assimilates the hydrological information from satellites and multi-UAS. The model is able to address surface water-groundwater interactions and reflect the effects of various infrastructures. Using Web-GIS technologies, the modeling results will be available online as interactive flood maps accessible to the public. To support the development and verification of this modeling system, surface and subsurface hydrological observations will be conducted in a number of small watersheds in the Coastal Bend region. We envision this system will provide an innovative means to benefit the forecasting, evaluation and mitigation of flash floods in costal regions.
Modeling urban flood risk territories for Riga city
NASA Astrophysics Data System (ADS)
Piliksere, A.; Sennikovs, J.; Virbulis, J.; Bethers, U.; Bethers, P.; Valainis, A.
2012-04-01
Riga, the capital of Latvia, is located on River Daugava at the Gulf of Riga. The main flooding risks of Riga city are: (1) storm caused water setup in South part of Gulf of Riga (storm event), (2) water level increase caused by Daugava River discharge maximums (spring snow melting event) and (3) strong rainfall or rapid snow melting in densely populated urban areas. The first two flooding factors were discussed previously (Piliksere et al, 2011). The aims of the study were (1) the identification of the flood risk situations in densely populated areas, (2) the quantification of the flooding scenarios caused by rain and snow melting events of different return periods nowadays, in the near future (2021-2050), far future (2071-2100) taking into account the projections of climate change, (3) estimation of groundwater level for Riga city, (4) the building and calibration of the hydrological mathematical model based on SWMM (EPA, 2004) for the domain potentially vulnerable for rain and snow melt flooding events, (5) the calculation of rain and snow melting flood events with different return periods, (6) mapping the potentially flooded areas on a fine grid. The time series of short term precipitation events during warm time period of year (id est. rain events) were analyzed for 35 year long time period. Annual maxima of precipitation intensity for events with different duration (5 min; 15 min; 1h; 3h; 6h; 12h; 1 day; 2 days; 4 days; 10 days) were calculated. The time series of long term simultaneous precipitation data and observations of the reduction of thickness of snow cover were analyzed for 27 year long time period. Snow thawing periods were detected and maximum of snow melting intensity for events with different intensity (1day; 2 days; 4 days; 7 days; 10 days) were calculated. According to the occurrence probability six scenarios for each event for nowadays, near and far future with return period once in 5, 10, 20, 50, 100 and 200 years were constructed based on the Gumbell extreme value analysis. The hydrological modelling driven by the temperature and precipitation data series from regional climate models were used for evaluation of rain event maximums in the future periods. The usage of the climate model data in hydrological models causes systematic errors; therefore the bias correction method (Sennikovs, Bethers, 2009) was applied for determination of the future rainfall intensities. SWMM model was built for the urban area. Objects of hydraulic importance (manifold, penstock, ditch, pumping station, weir, well, catchment sub-basin etc.) were included in the model. There exist pure rain sewage system and mixed rain-water/household sewage system in Riga. Sewage system with wastewater load proportional to population density was taken account and calibrated. Model system was calibrated for a real rain event against the water flux time series into sewage treatment plant of Riga. High resolution (~1.5 points per square meter) digital terrain map was used as the base for finite element mesh for the geospatial mapping of results of hydraulic calculations. Main results of study are (1) detection of the hot spots of densely populated urban areas; (2) identification of the weak chains of the melioration and sewage systems; (3) mapping the elevation of ground water mainly caused by snow melting. A.Piliksere, A.Valainis, J.Seņņikovs, (2011), A flood risk assessment for Riga city taking account climate changes, EGU, Vienna, Austria. EPA, (2004), Storm water management model. User's manual version 5.0. US Environmental Protection Agency J.Sennikovs, U.Bethers, (2009), Statistical downscaling method of regional climate model results for hydrological modelling. 18th World IMACS/MODSIM Congress, Cairns, Australia.
Prospects for development of unified global flood observation and prediction systems (Invited)
NASA Astrophysics Data System (ADS)
Lettenmaier, D. P.
2013-12-01
Floods are among the most damaging of natural hazards, with global flood losses in 2011 alone estimated to have exceeded $100B. Historically, flood economic damages have been highest in the developed world (due in part to encroachment on historical flood plains), but loss of life, and human impacts have been greatest in the developing world. However, as the 2011 Thailand floods show, industrializing countries, many of which do not have well developed flood protection systems, are increasingly vulnerable to economic damages as they become more industrialized. At present, unified global flood observation and prediction systems are in their infancy; notwithstanding that global weather forecasting is a mature field. The summary for this session identifies two evolving capabilities that hold promise for development of more sophisticated global flood forecast systems: global hydrologic models and satellite remote sensing (primarily of precipitation, but also of flood inundation). To this I would add the increasing sophistication and accuracy of global precipitation analysis (and forecast) fields from numerical weather prediction models. In this brief overview, I will review progress in all three areas, and especially the evolution of hydrologic data assimilation which integrates modeling and data sources. I will also comment on inter-governmental and inter-agency cooperation, and related issues that have impeded progress in the development and utilization of global flood observation and prediction systems.
A global flash flood forecasting system
NASA Astrophysics Data System (ADS)
Baugh, Calum; Pappenberger, Florian; Wetterhall, Fredrik; Hewson, Tim; Zsoter, Ervin
2016-04-01
The sudden and devastating nature of flash flood events means it is imperative to provide early warnings such as those derived from Numerical Weather Prediction (NWP) forecasts. Currently such systems exist on basin, national and continental scales in Europe, North America and Australia but rely on high resolution NWP forecasts or rainfall-radar nowcasting, neither of which have global coverage. To produce global flash flood forecasts this work investigates the possibility of using forecasts from a global NWP system. In particular we: (i) discuss how global NWP can be used for flash flood forecasting and discuss strengths and weaknesses; (ii) demonstrate how a robust evaluation can be performed given the rarity of the event; (iii) highlight the challenges and opportunities in communicating flash flood uncertainty to decision makers; and (iv) explore future developments which would significantly improve global flash flood forecasting. The proposed forecast system uses ensemble surface runoff forecasts from the ECMWF H-TESSEL land surface scheme. A flash flood index is generated using the ERIC (Enhanced Runoff Index based on Climatology) methodology [Raynaud et al., 2014]. This global methodology is applied to a series of flash floods across southern Europe. Results from the system are compared against warnings produced using the higher resolution COSMO-LEPS limited area model. The global system is evaluated by comparing forecasted warning locations against a flash flood database of media reports created in partnership with floodlist.com. To deal with the lack of objectivity in media reports we carefully assess the suitability of different skill scores and apply spatial uncertainty thresholds to the observations. To communicate the uncertainties of the flash flood system output we experiment with a dynamic region-growing algorithm. This automatically clusters regions of similar return period exceedence probabilities, thus presenting the at-risk areas at a spatial resolution appropriate to the NWP system. We then demonstrate how these warning areas could eventually complement existing global systems such as the Global Flood Awareness System (GloFAS), to give warnings of flash floods. This work demonstrates the possibility of creating a global flash flood forecasting system based on forecasts from existing global NWP systems. Future developments, in post-processing for example, will need to address an under-prediction bias, for extreme point rainfall, that is innate to current-generation global models.
Development of a model-based flood emergency management system in Yujiang River Basin, South China
NASA Astrophysics Data System (ADS)
Zeng, Yong; Cai, Yanpeng; Jia, Peng; Mao, Jiansu
2014-06-01
Flooding is the most frequent disaster in China. It affects people's lives and properties, causing considerable economic loss. Flood forecast and operation of reservoirs are important in flood emergency management. Although great progress has been achieved in flood forecast and reservoir operation through using computer, network technology, and geographic information system technology in China, the prediction accuracy of models are not satisfactory due to the unavailability of real-time monitoring data. Also, real-time flood control scenario analysis is not effective in many regions and can seldom provide online decision support function. In this research, a decision support system for real-time flood forecasting in Yujiang River Basin, South China (DSS-YRB) is introduced in this paper. This system is based on hydrological and hydraulic mathematical models. The conceptual framework and detailed components of the proposed DSS-YRB is illustrated, which employs real-time rainfall data conversion, model-driven hydrologic forecasting, model calibration, data assimilation methods, and reservoir operational scenario analysis. Multi-tiered architecture offers great flexibility, portability, reusability, and reliability. The applied case study results show the development and application of a decision support system for real-time flood forecasting and operation is beneficial for flood control.
Impact of social preparedness on flood early warning systems
NASA Astrophysics Data System (ADS)
Girons Lopez, M.; Di Baldassarre, G.; Seibert, J.
2017-01-01
Flood early warning systems play a major role in the disaster risk reduction paradigm as cost-effective methods to mitigate flood disaster damage. The connections and feedbacks between the hydrological and social spheres of early warning systems are increasingly being considered as key aspects for successful flood mitigation. The behavior of the public and first responders during flood situations, determined by their preparedness, is heavily influenced by many behavioral traits such as perceived benefits, risk awareness, or even denial. In this study, we use the recency of flood experiences as a proxy for social preparedness to assess its impact on the efficiency of flood early warning systems through a simple stylized model and implemented this model using a simple mathematical description. The main findings, which are based on synthetic data, point to the importance of social preparedness for flood loss mitigation, especially in circumstances where the technical forecasting and warning capabilities are limited. Furthermore, we found that efforts to promote and preserve social preparedness may help to reduce disaster-induced losses by almost one half. The findings provide important insights into the role of social preparedness that may help guide decision-making in the field of flood early warning systems.
Study and optimisation of SIMS performed with He+ and Ne+ bombardment
NASA Astrophysics Data System (ADS)
Pillatsch, L.; Vanhove, N.; Dowsett, D.; Sijbrandij, S.; Notte, J.; Wirtz, T.
2013-10-01
The combination of the high-brightness He+/Ne+ atomic level ion source with the detection capabilities of secondary ion mass spectrometry (SIMS) opens up the prospect of obtaining chemical information with high lateral resolution and high sensitivity on the Zeiss ORION helium ion microscope (HIM). A feasibility study with He+ and Ne+ ion bombardment is presented in order to determine the performance of SIMS analyses using the HIM. Therefore, the sputtering yields, useful yields and detection limits obtained for metallic (Al, Ni and W) as well as semiconductor samples (Si, Ge, GaAs and InP) were investigated. All the experiments were performed on a Cameca IMS4f SIMS instrument which was equipped with a caesium evaporator and oxygen flooding system. For most of the elements, useful yields in the range of 10-4 to 3 × 10-2 were measured with either O2 or Cs flooding. SIMS experiments performed directly on the ORION with a prototype secondary ion extraction and detection system lead to results that are consistent with those obtained on the IMS4f. Taking into account the obtained useful yields and the analytical conditions, such as the ion current and typical dwell time on the ORION HIM, detection limits in the at% range and better can be obtained during SIMS imaging at 10 nm lateral resolution with Ne+ bombardment and down to the ppm level when a lateral resolution of 100 nm is chosen. Performing SIMS on the HIM with a good detection limit while maintaining an excellent lateral resolution (<50 nm) is therefore very promising.
Urban flood risk mitigation: from vulnerability assessment to resilient city
NASA Astrophysics Data System (ADS)
Serre, D.; Barroca, B.
2009-04-01
Urban flood risk mitigation: from vulnerability assessment to resilient city Bruno Barroca1, Damien Serre2 1Laboratory of Urban Engineering, Environment and Building (L G U E H) - Université de Marne-la-Vallée - Pôle Ville, 5, Bd Descartes - Bâtiment Lavoisier - 77454 Marne la Vallée Cedex 2 - France 2City of Paris Engineering School, Construction - Environment Department, 15 rue Fénelon, 75010 Paris, France In France, as in Europe and more generally throughout the world, river floods have been increasing in frequency and severity over the last ten years, and there are more instances of rivers bursting their banks, aggravating the impact of the flooding of areas supposedly protected by flood defenses. Despite efforts made to well maintain the flood defense assets, we often observe flood defense failures leading to finally increase flood risk in protected area during major flood events. Furthermore, flood forecasting models, although they benefit continuous improvements, remain partly inaccurate due to uncertainties populated all along data calculation processes. These circumstances obliged stakeholders and the scientific communities to manage flood risk by integrating new concepts like stakes management, vulnerability assessments and more recently urban resilience development. Definitively, the goal is to reduce flood risk by managing of course flood defenses and improving flood forecasting models, but also stakes and vulnerability of flooded areas to achieve urban resilience face to flood events. Vulnerability to flood is essentially concentrated in urban areas. Assessing vulnerability of a city is very difficult. Indeed, urban area is a complex system composed by a sum of technical sub-systems as complex as the urban area itself. Assessing city vulnerability consists in talking into account each sub system vulnerability and integrating all direct and indirect impacts generally depending from city shape and city spatial organization. At this time, although some research activities have been undertaken, there are no specific methods and tools to assess flood vulnerability at the scale of the city. Indeed, by studying literature we can list some vulnerability indicators and a few Geographic Information System (GIS) tools. But generally indicators and GIS are not developed specifically at the city scale: often a regional scale is used. Analyzing vulnerability at this scale needs more accurate and formalized indicators and GIS tools. The second limit of existing GIS is temporal: even if vulnerability could be assessed and localized through GIS, such tools cannot assist city managers in their decision to efficiency recover after a severe flood event. Due to scale and temporal limits, methods and tools available to assess urban vulnerability need large improvements. Talking into account all these considerations and limits, our research is focusing on: • vulnerability indicators design; • recovery scenarios design; • GIS for city vulnerability assessment and recovery scenarios. Dealing with vulnerability indicators, the goal is to design a set of indicators of city sub systems. Sub systems are seen like assets of high value and complex and interdependent infrastructure networks (i.e. power supplies, communications, water, transport etc.). The infrastructure networks are critical for the continuity of economic activities as well as for the people's basic living needs. Their availability is also required for fast and effective recovery after flood disasters. The severity of flood damage therefore largely depends on the degree that both high value assets and critical urban infrastructure are affected, either directly or indirectly. To face the challenge of designing indicators, a functional model of the city system (and sub systems) has to be built to analyze the system response to flood solicitation. Then, a coherent and an efficient set of vulnerability of indicators could be built up. With such methods city stakeholders will be informed on how and how much their systems are vulnerable. It is a first level of information that has to be completed to become a real decision making tool. Indeed, we have seen that major floods cause almost always failures in the flood defense system. So potentially the city could face a flood event and managers recovery works. Knowing the vulnerability of the city, direct and indirect impacts, how can managers optimize recovery actions? Our research will focus first on proposing recovery scenarios based on the city system and second on vulnerability indicators to first limit damages during floods and to speed up recovery actions. At last, a GIS will be developed to assist stakeholders to take spatial measures to reduce city system weakness before a flood event and to help them to decide on how to optimize recovery actions after a flood event. Dealing with these two temporal scales will allow obtaining more flood resilient cities.
Coastal Floods: Urban Planning as a Resilience System
NASA Astrophysics Data System (ADS)
Diez Gonzalez, J. J.; Esteban, M. D.; Monnot, J. V.; López Gutiérrez, J. S.; Negro Valdecantos, V.; Calderón, E. J.; Márquez Paniagua, P.; Silvestre, J. M.
2012-04-01
Despite some research efforts can be found across the literature, FRe system (Flood resilient system) is still a vaguely defined concept. Therefore, a comprehensive presentation of existing FRe systems would provide valuable contribution in order to illuminate objects laying behind this term. A systematical literature review scanning existing FRe objects will submerge us in a melting pot involving an extremely wide and heterogeneous range of elements like land planning, opening barriers, river channeling, rain forecasting… Carrying out an analyze of the resulting matter and focusing on the nature and spatial range of application of each element, a FRe objects comprehensive typology will be sorted out, leading into the end to a better understanding of the ways human societies can improve their resilience against floods. Coastal areas have been characterized by an urban expansion due mainly to the increase and displacement of the population, being this process highly increasing during the last century. On the other hand, climate has been changing leading to the increase of coastal floods, through both sea level rise and several meteorological phenomena accentuation. And also, other longer term local/regional coastal changes, most occasionally favoring floods, interfere leading to more frequent and intense flood risks and damages. As "living with floods" became an objective in many coastal cities, the previous clas-sification will be put into practice focusing on one particular FRe system scale: Urban Flood Resilience. This resilience can be achieved by means of planning procedures and building infrastructures, but in many cases these measures cannot be enough, having to be complemented with different technologies and systems. With suitable applications, Flood Resilience Systems substantially reduce damages, costs and health impacts associated with flood hazards. The importance of the urban planning as a Flood Resilience System in coastal areas will be analyzed in the research project FP7 - SMARTEST by means of different cases study: cold drop floods (Valencia 1776, 1957 and 1982; and Murcia, 1879 and 1997), hurricanes on Caribbean and western North-Atlantic areas, or to typhoons.
Flood-Inundation Maps for a 1.6-Mile Reach of Salt Creek, Wood Dale, Illinois
Soong, David T.; Murphy, Elizabeth A.; Sharpe, Jennifer B.
2012-01-01
Digital flood-inundation maps for a 1.6-mile reach of Salt Creek from upstream of the Chicago, Milwaukee, St. Paul & Pacific Railroad to Elizabeth Drive, Wood Dale, Illinois, were created by the U.S. Geological Survey (USGS) in cooperation with the DuPage County Stormwater Management Division. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights) at the USGS streamgage on Salt Creek at Wood Dale, Illinois (station number 05531175). Current conditions at the USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?05531175. In this study, flood profiles were computed for the stream reach by means of a one-dimensional unsteady flow Full EQuations (FEQ) model. The unsteady flow model was verified by comparing the rating curve output for a September 2008 flood event to discharge measurements collected at the Salt Creek at Wood Dale gage. The hydraulic model was then used to determine 14 water-surface profiles for gage heights at 0.5-ft intervals referenced to the streamgage datum and ranging from less than bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a Geographic Information System (GIS) Digital Elevation Model (DEM) (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The areal extent of the inundation was verified with high-water marks from a flood in July 2010 with a peak gage height of 14.08 ft recorded at the Salt Creek at Wood Dale gage. The availability of these maps along with Internet information regarding current gage height from USGS streamgages provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post-flood recovery efforts.
NASA Astrophysics Data System (ADS)
Matingo, Thomas; Gumindoga, Webster; Makurira, Hodson
2018-05-01
Flash floods are experienced almost annually in the ungauged Mbire District of the Middle Zambezi Basin. Studies related to hydrological modelling (rainfall-runoff) and flood forecasting require major inputs such as precipitation which, due to shortage of observed data, are increasingly using indirect methods for estimating precipitation. This study therefore evaluated performance of CMORPH and TRMM satellite rainfall estimates (SREs) for 30 min, 1 h, 3 h and daily intensities through hydrologic and flash flood modelling in the Lower Middle Zambezi Basin for the period 2013-2016. On a daily timestep, uncorrected CMORPH and TRMM show Probability of Detection (POD) of 61 and 59 %, respectively, when compared to rain gauge observations. The best performance using Correlation Coefficient (CC) was 70 and 60 % on daily timesteps for CMORPH and TRMM, respectively. The best RMSE for CMORPH was 0.81 % for 30 min timestep and for TRMM was 2, 11 % on 3 h timestep. For the year 2014 to 2015, the HEC-HMS (Hydrological Engineering Centre-Hydrological Modelling System) daily model calibration Nash Sutcliffe efficiency (NSE) for Musengezi sub catchment was 59 % whilst for Angwa it was 55 %. Angwa sub-catchment daily NSE results for the period 2015-2016 was 61 %. HEC-RAS flash flood modeling at 100, 50 and 25 year return periods for Angwa sub catchment, inundated 811 and 867 ha for TRMM rainfall simulated discharge at 3 h and daily timesteps, respectively. For CMORPH generated rainfall, the inundation was 818, 876, 890 and 891 ha at daily, 3 h, 1 h and 30 min timesteps. The 30 min time step for CMORPH effectively captures flash floods with the measure of agreement between simulated flood extent and ground control points of 69 %. For TRMM, the 3 h timestep effectively captures flash floods with coefficient of 67 %. The study therefore concludes that satellite products are most effective in capturing localized hydrological processes such as flash floods for sub-daily rainfall, because of improved spatial and temporal resolution.
An experimental system for flood risk forecasting at global scale
NASA Astrophysics Data System (ADS)
Alfieri, L.; Dottori, F.; Kalas, M.; Lorini, V.; Bianchi, A.; Hirpa, F. A.; Feyen, L.; Salamon, P.
2016-12-01
Global flood forecasting and monitoring systems are nowadays a reality and are being applied by an increasing range of users and practitioners in disaster risk management. Furthermore, there is an increasing demand from users to integrate flood early warning systems with risk based forecasts, combining streamflow estimations with expected inundated areas and flood impacts. To this end, we have developed an experimental procedure for near-real time flood mapping and impact assessment based on the daily forecasts issued by the Global Flood Awareness System (GloFAS). The methodology translates GloFAS streamflow forecasts into event-based flood hazard maps based on the predicted flow magnitude and the forecast lead time and a database of flood hazard maps with global coverage. Flood hazard maps are then combined with exposure and vulnerability information to derive flood risk. Impacts of the forecasted flood events are evaluated in terms of flood prone areas, potential economic damage, and affected population, infrastructures and cities. To further increase the reliability of the proposed methodology we integrated model-based estimations with an innovative methodology for social media monitoring, which allows for real-time verification of impact forecasts. The preliminary tests provided good results and showed the potential of the developed real-time operational procedure in helping emergency response and management. In particular, the link with social media is crucial for improving the accuracy of impact predictions.
NASA Astrophysics Data System (ADS)
Khanh Triet Nguyen, Van; Dung Nguyen, Viet; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko
2017-04-01
Flooding in the Mekong Delta is an annual phenomenon causing inundation of large parts of the delta. This flooding is vital for the geomorphological stability of the delta, but is also the backbone of the highly productive agro-economy. However, extraordinary high floods are on the other hand a major hazard for the millions of people living in the delta. Therefore large scale developments of hydraulic structures took place in the Vietnamese part of the delta in the last decades. Particularly in the areas prone to deep and long lasting inundations many flood protection structures, mainly dykes, were built. These structures enable a blocking of inundation in large parts of these areas and by this the cropping of a third crop per year during the flood season. However, these structures are frequently blamed for increasing water levels in the areas downstream. Thus this study aimed at the investigation and attribution of changes in flood hazard in the Vietnamese Mekong Delta (VMD) due to high-dyke construction in deep flood prone areas, mainly in An Giang and Dong Thap provinces. This analysis started with the estimation of monotonic trends at key gauging stations in the delta: Kratie at the apex of the Mekong delta; Tan Chau and Chau Doc in the VMD just upstream of the areas with high-dyke construction; and Can Tho and My Thuan, located downstream of the high-dyke areas. The tests were undertaken assuming different magnitudes of errors in the data using historical records from 1978 - 2015, using the Mann-Kendall test and Sen's slope estimation. The obtained trends were thus tested for robustness against data errors. In order to obtain a better understanding of trends in the flood dynamics, the tests are performed on both flood peak and flood duration. In addition, the Pettitt test was applied to identify step changes in the water level data at 4 gauge stations located in the VMD. After the trend analysis, the impacts of high-dyke development were quantified with the help of a quasi-2D hydrodynamic flood inundation model, using the latest comprehensive dyke survey and topographical data for the VMD. Changes in delta inundation dynamics with-/without- high-dyke systems were investigated in two different model setups, simulating the two recent most severe flood events in 2000 and 2011 with their original dike system as reference, and interchanged dyke system in order to quantify the induced hydraulic changes. In a similar manner the specific influence of the upper boundary, i.e. the flood characteristics of the two events, and the lower boundary, i.e. the tidal influence, on the water levels in the VMD was quantified and compared to the influence of the dyke system. Results of the trend test revealed negative but low significant trends at Chau Doc (p ≥ 0.1) and Tan Chau (p ≥ 0.05) at the upper part of the delta within the studied period. On the contrary, strong increasing and highly significant trends were detected at Can Tho and My Thuan downstream of fully flood protection areas, with a step change around the year 2000 (p < 0.001). Of which, an increase of ˜9.0÷13.0 cm in flood peak and ˜10 days in duration were attributed to high-dyke development upstream as results of the model simulation. We also found that the most dominant factor altering flood dynamics at these locations are changes of lower boundaries, causing differences of about +19.0 cm and +32.0 cm at My Thuan and Can Tho respectively for the two flood events. The third considered factor, influence of changing of inflow, was mostly dominant in the upper parts of the VMD. It was accounted for ˜7÷8 cm of total water level alteration in the middle parts of the delta, compared to about -27 cm at the border of Vietnam and Cambodia. Thus the claims that the dyke development has altered the water levels during floods in the areas downstream can be confirmed, but it has to be noted that the lower boundary, i.e. higher sea levels caused by sea level rise in combination with the widely observed land subsidence have an even larger impact. Based on these results, it is recommended to develop flood risk management strategies that use the high dyke areas as retention areas in order to mitigate the flood hazard downstream, if large flood events are forecasted.
A fiber Bragg grating acceleration sensor for ground surveillance
NASA Astrophysics Data System (ADS)
Jiang, Shaodong; Zhang, Faxiang; Lv, Jingsheng; Ni, Jiasheng; Wang, Chang
2017-10-01
Ground surveillance system is a kind of intelligent monitoring equipment for detecting and tracking the ground target. This paper presents a fiber Bragg grating (FBG) acceleration sensor for ground surveillance, which has the characteristics of no power supply, anti-electromagnetic interference, easy large-scale networking, and small size. Which make it able to achieve the advantage of the ground surveillance system while avoiding the shortcoming of the electric sensing. The sensor has a double cantilever beam structure with a sensitivity of 1000 pm/g. Field experiment has been carried out on a flood beach to examine the sensor performance. The result shows that the detection distance on the walking of personnel reaches 70m, and the detection distance on the ordinary motor vehicle reaches 200m. The performance of the FBG sensor can satisfy the actual needs of the ground surveillance system.
NASA Technical Reports Server (NTRS)
2009-01-01
Topics covered include: Direct-Solve Image-Based Wavefront Sensing; Use of UV Sources for Detection and Identification of Explosives; Using Fluorescent Viruses for Detecting Bacteria in Water; Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System; Volcano Monitor: Autonomous Triggering of In-Situ Sensors; Wireless Fluid-Level Sensors for Harsh Environments; Interference-Detection Module in a Digital Radar Receiver; Modal Vibration Analysis of Large Castings; Structural/Radiation-Shielding Epoxies; Integrated Multilayer Insulation; Apparatus for Screening Multiple Oxygen-Reduction Catalysts; Determining Aliasing in Isolated Signal Conditioning Modules; Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems; Spectrum Analyzers Incorporating Tunable WGM Resonators; Quantum-Well Thermophotovoltaic Cells; Bounded-Angle Iterative Decoding of LDPC Codes; Conversion from Tree to Graph Representation of Requirements; Parallel Hybrid Vehicle Optimal Storage System; and Anaerobic Digestion in a Flooded Densified Leachbed.
Near Real Time Flood Warning System for National Capital Territory of Delhi
NASA Astrophysics Data System (ADS)
Goyal, A.; Yadav, H.; Tyagi, H.; Gosain, A. K.
2017-12-01
Extreme floods are common phenomena during Indian Monsoons. The National Capital Territory area of India, Delhi, frequently experiences fluvial as well as pluvial inundation due to its proximity to river Yamuna and poor functioning of its stormwater drainage system. The urban floods result in severe waterlogging and heavy traffic snarls, bringing life in this megapolis to a halt. The city has witnessed six major floods since 1900 and thus its residents are well conscious of potential flood risks but the city still lacks a flood warning system. The flood related risks can be considerably reduced, if not eliminated, by issuing timely warnings and implementing adaptive measures. Therefore, the present study attempts to develop a web based platform that integrates Web-GIS technology and mathematical simulation modelling to provide an effective and reliable early flood warning service for Delhi. The study makes use of India Metorological Department's Doppler radar-derived near real time rainfall estimates of 15 minutes time step. The developed SWMM model has been validated using information from gauges, monitoring sensors and crowd sourcing techniques and utilises capabilities of cloud computing on server side for fast processing. This study also recommends safe evacuation policy and remedial measures for flooding hotspots as part of flood risk management plan. With heightened risk of floods in fast urbanizing areas, this work becomes highly pertinent as flood warning system with adequate lead time can not only save precious lives but can also substantially reduce flood damages.
Urban Flood Prevention and Early Warning System in Jinan City
NASA Astrophysics Data System (ADS)
Feng, Shiyuan; Li, Qingguo
2018-06-01
The system construction of urban flood control and disaster reduction in China is facing pressure and challenge from new urban water disaster. Under the circumstances that it is difficult to build high standards of flood protection engineering measures in urban areas, it is particularly important to carry out urban flood early warning. In Jinan City, a representative inland area, based on the index system of early warning of flood in Jinan urban area, the method of fuzzy comprehensive evaluation was adopted to evaluate the level of early warning. Based on the cumulative rainfall of 3 hours, the CAflood simulation results based on cellular automaton model of urban flooding were used as evaluation indexes to realize the accuracy and integration of urban flood control early warning.
Flood- and drought-related natural hazards activities of the U.S. Geological Survey in New England
Lombard, Pamela J.
2016-03-23
Tools for natural hazard assessment and mitigation • Light detection and ranging (lidar) remote sensing technology • StreamStats Web-based tool for streamflow statistics • Flood inundation mapper
Urban Flood Management with Integrated Inland-River System in Seoul
NASA Astrophysics Data System (ADS)
Moon, Y. I.; Kim, J. S.; Yuk, J. M.
2015-12-01
Global warming and climate change have caused significant damage and loss of life worldwide. The pattern of natural disasters has gradually diversified and their frequency is increasing. The impact of climate change on flood risk in urban rivers is of particular interest because these areas are typically densely populated. The occurrence of urban river flooding due to climate change not only causes significant loss of life and property but also causes health and social problems. It is therefore necessary to develop a scientific urban flood management system to cope with and reduce the impacts of climate change, including flood damage. In this study, we are going to introduce Integrated Inland-River Flood Analysis System in Seoul to conduct predictions on flash rain or short-term rainfall by using radar and satellite information and perform prompt and accurate prediction on the inland flooded areas. In addition, this urban flood management system can be used as a tool for decision making of systematic disaster prevention through real-time monitoring.
Social sensing of floods in the UK
Williams, Hywel T. P.
2018-01-01
“Social sensing” is a form of crowd-sourcing that involves systematic analysis of digital communications to detect real-world events. Here we consider the use of social sensing for observing natural hazards. In particular, we present a case study that uses data from a popular social media platform (Twitter) to detect and locate flood events in the UK. In order to improve data quality we apply a number of filters (timezone, simple text filters and a naive Bayes ‘relevance’ filter) to the data. We then use place names in the user profile and message text to infer the location of the tweets. These two steps remove most of the irrelevant tweets and yield orders of magnitude more located tweets than we have by relying on geo-tagged data. We demonstrate that high resolution social sensing of floods is feasible and we can produce high-quality historical and real-time maps of floods using Twitter. PMID:29385132
Social sensing of floods in the UK.
Arthur, Rudy; Boulton, Chris A; Shotton, Humphrey; Williams, Hywel T P
2018-01-01
"Social sensing" is a form of crowd-sourcing that involves systematic analysis of digital communications to detect real-world events. Here we consider the use of social sensing for observing natural hazards. In particular, we present a case study that uses data from a popular social media platform (Twitter) to detect and locate flood events in the UK. In order to improve data quality we apply a number of filters (timezone, simple text filters and a naive Bayes 'relevance' filter) to the data. We then use place names in the user profile and message text to infer the location of the tweets. These two steps remove most of the irrelevant tweets and yield orders of magnitude more located tweets than we have by relying on geo-tagged data. We demonstrate that high resolution social sensing of floods is feasible and we can produce high-quality historical and real-time maps of floods using Twitter.
Cohn, T.A.; England, J.F.; Berenbrock, C.E.; Mason, R.R.; Stedinger, J.R.; Lamontagne, J.R.
2013-01-01
he Grubbs-Beck test is recommended by the federal guidelines for detection of low outliers in flood flow frequency computation in the United States. This paper presents a generalization of the Grubbs-Beck test for normal data (similar to the Rosner (1983) test; see also Spencer and McCuen (1996)) that can provide a consistent standard for identifying multiple potentially influential low flows. In cases where low outliers have been identified, they can be represented as “less-than” values, and a frequency distribution can be developed using censored-data statistical techniques, such as the Expected Moments Algorithm. This approach can improve the fit of the right-hand tail of a frequency distribution and provide protection from lack-of-fit due to unimportant but potentially influential low flows (PILFs) in a flood series, thus making the flood frequency analysis procedure more robust.
NASA Astrophysics Data System (ADS)
Cohn, T. A.; England, J. F.; Berenbrock, C. E.; Mason, R. R.; Stedinger, J. R.; Lamontagne, J. R.
2013-08-01
The Grubbs-Beck test is recommended by the federal guidelines for detection of low outliers in flood flow frequency computation in the United States. This paper presents a generalization of the Grubbs-Beck test for normal data (similar to the Rosner (1983) test; see also Spencer and McCuen (1996)) that can provide a consistent standard for identifying multiple potentially influential low flows. In cases where low outliers have been identified, they can be represented as "less-than" values, and a frequency distribution can be developed using censored-data statistical techniques, such as the Expected Moments Algorithm. This approach can improve the fit of the right-hand tail of a frequency distribution and provide protection from lack-of-fit due to unimportant but potentially influential low flows (PILFs) in a flood series, thus making the flood frequency analysis procedure more robust.
Flood-inundation maps for Indian Creek and Tomahawk Creek, Johnson County, Kansas, 2014
Peters, Arin J.; Studley, Seth E.
2016-01-25
Digital flood-inundation maps for a 6.4-mile upper reach of Indian Creek from College Boulevard to the confluence with Tomahawk Creek, a 3.9-mile reach of Tomahawk Creek from 127th Street to the confluence with Indian Creek, and a 1.9-mile lower reach of Indian Creek from the confluence with Tomahawk Creek to just beyond the Kansas/Missouri border at State Line Road in Johnson County, Kansas, were created by the U.S. Geological Survey in cooperation with the city of Overland Park, Kansas. The flood-inundation maps, which can be accessed through the U.S. Geological Survey Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgages on Indian Creek at Overland Park, Kansas; Indian Creek at State Line Road, Leawood, Kansas; and Tomahawk Creek near Overland Park, Kansas. Near real time stages at these streamgages may be obtained on the Web from the U.S. Geological Survey National Water Information System at http://waterdata.usgs.gov/nwis or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at these sites.Flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model. The model was calibrated for each reach by using the most current stage-discharge relations at the streamgages. The hydraulic models were then used to determine 15 water-surface profiles for Indian Creek at Overland Park, Kansas; 17 water-surface profiles for Indian Creek at State Line Road, Leawood, Kansas; and 14 water-surface profiles for Tomahawk Creek near Overland Park, Kansas, for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the next interval above the 0.2-percent annual exceedance probability flood level (500-year recurrence interval). The simulated water-surface profiles were then combined in a geographic information system with a digital elevation model derived from light detection and ranging data (having a 0.429-foot vertical and 0.228-foot horizontal accuracy) to delineate the area flooded at each water level.The availability of these maps, along with Web information regarding current stage from the U.S. Geological Survey streamgages and forecasted high-flow stages from the National Weather Service, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations, road closures, and postflood recovery efforts.
Information Communication using Knowledge Engine on Flood Issues
NASA Astrophysics Data System (ADS)
Demir, I.; Krajewski, W. F.
2012-04-01
The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to and visualization of flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, and other flood-related data for communities in Iowa. The system is designed for use by general public, often people with no domain knowledge and poor general science background. To improve effective communication with such audience, we have introduced a new way in IFIS to get information on flood related issues - instead of by navigating within hundreds of features and interfaces of the information system and web-based sources-- by providing dynamic computations based on a collection of built-in data, analysis, and methods. The IFIS Knowledge Engine connects to distributed sources of real-time stream gauges, and in-house data sources, analysis and visualization tools to answer questions grouped into several categories. Users will be able to provide input based on the query within the categories of rainfall, flood conditions, forecast, inundation maps, flood risk and data sensors. Our goal is the systematization of knowledge on flood related issues, and to provide a single source for definitive answers to factual queries. Long-term goal of this knowledge engine is to make all flood related knowledge easily accessible to everyone, and provide educational geoinformatics tool. The future implementation of the system will be able to accept free-form input and voice recognition capabilities within browser and mobile applications. We intend to deliver increasing capabilities for the system over the coming releases of IFIS. This presentation provides an overview of our Knowledge Engine, its unique information interface and functionality as an educational tool, and discusses the future plans for providing knowledge on flood related issues and resources.
Fifty-year flood-inundation maps for Nacaome, Honduras
Kresch, David L.; Mastin, M.C.; Olsen, T.D.
2002-01-01
After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Nacaome that would be inundated by 50-year floods on Rio Nacaome, Rio Grande, and Rio Guacirope. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Nacaome as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for 50-year-floods on Rio Nacaome, Rio Grande, and Rio Guacirope at Nacaome were computed using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and ground surveys at two bridges. The estimated 50-year-flood discharge for Rio Nacaome at Nacaome, 5,040 cubic meters per second, was computed as the drainage-area-adjusted weighted average of two independently estimated 50-year-flood discharges for the gaging station Rio Nacaome en Las Mercedes, located about 13 kilometers upstream from Nacaome. One of the discharges, 4,549 cubic meters per second, was estimated from a frequency analysis of the 16 years of peak-discharge record for the gage, and the other, 1,922 cubic meters per second, was estimated from a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The weighted-average of the two discharges is 3,770 cubic meters per second. The 50-year-flood discharges for Rio Grande, 3,890 cubic meters per second, and Rio Guacirope, 1,080 cubic meters per second, were also computed by adjusting the weighted-average 50-year-flood discharge for the Rio Nacaome en Las Mercedes gaging station for the difference in drainage areas between the gage and these river reaches.
Flood-inundation maps for the Driftwood River and Sugar Creek near Edinburgh, Indiana
Fowler, Kathleen K.; Kim, Moon H.; Menke, Chad D.
2012-01-01
Digital flood-inundation maps for an 11.2 mile reach of the Driftwood River and a 5.2 mile reach of Sugar Creek, both near Edinburgh, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Camp Atterbury Joint Maneuver Training Center, Edinburgh, Indiana. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. Current conditions at the USGS streamgage in Indiana may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/current/?type=flow. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system at http://water.weather.gov/ahps/. The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. The hydraulic model was then used to determine elevations throughout the study reaches for nine water-surface profiles for flood stages at 1-ft intervals referenced to the streamgage datum and ranging from bankfull to nearly the highest recorded water level at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. The simulated water-surface profiles were then combined with a geospatial digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps along with real-time information available online regarding current stage from USGS streamgages and forecasted stream stages from the NWS provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post flood recovery efforts.
An operational procedure for rapid flood risk assessment in Europe
NASA Astrophysics Data System (ADS)
Dottori, Francesco; Kalas, Milan; Salamon, Peter; Bianchi, Alessandra; Alfieri, Lorenzo; Feyen, Luc
2017-07-01
The development of methods for rapid flood mapping and risk assessment is a key step to increase the usefulness of flood early warning systems and is crucial for effective emergency response and flood impact mitigation. Currently, flood early warning systems rarely include real-time components to assess potential impacts generated by forecasted flood events. To overcome this limitation, this study describes the benchmarking of an operational procedure for rapid flood risk assessment based on predictions issued by the European Flood Awareness System (EFAS). Daily streamflow forecasts produced for major European river networks are translated into event-based flood hazard maps using a large map catalogue derived from high-resolution hydrodynamic simulations. Flood hazard maps are then combined with exposure and vulnerability information, and the impacts of the forecasted flood events are evaluated in terms of flood-prone areas, economic damage and affected population, infrastructures and cities.An extensive testing of the operational procedure has been carried out by analysing the catastrophic floods of May 2014 in Bosnia-Herzegovina, Croatia and Serbia. The reliability of the flood mapping methodology is tested against satellite-based and report-based flood extent data, while modelled estimates of economic damage and affected population are compared against ground-based estimations. Finally, we evaluate the skill of risk estimates derived from EFAS flood forecasts with different lead times and combinations of probabilistic forecasts. Results highlight the potential of the real-time operational procedure in helping emergency response and management.
Timing of floods in southeastern China: Seasonal properties and potential causes
NASA Astrophysics Data System (ADS)
Zhang, Qiang; Gu, Xihui; Singh, Vijay P.; Shi, Peijun; Luo, Ming
2017-09-01
Flood hazards and flood risks in southeastern China have been causing increasing concerns due to dense population and highly-developed economy. This study attempted to address changes of seasonality, timing of peak floods and variability of occurrence date of peak floods using circular statistical methods and the modified Mann-Kendall trend detection method. The causes of peak flood changes were also investigated. Results indicated that: (1) floods were subject to more seasonality and temporal clustering when compared to precipitation extremes. However, seasonality of floods and extreme precipitation was subject to spatial heterogeneity in northern Guangdong. Similar changing patterns of peak floods and extreme precipitation were found in coastal regions; (2) significant increasing/decreasing seasonality, but no confirmed spatial patterns, were observed for peak floods and extreme precipitation. Peak floods in northern Guangdong province had decreasing variability, but had larger variability in coastal regions; (3) tropical cyclones had remarkable impacts on extreme precipitation changes in coastal regions of southeastern China, and peak floods as well. The landfalling of tropical cyclones was decreasing and concentrated during June-September; this is the major reason for earlier but enhanced seasonality of peak floods in coastal regions. This study sheds new light on flood behavior in coastal regions in a changing environment.
NASA Astrophysics Data System (ADS)
Salagnac, J.-L.; Diez, J.; Tourbier, J.
2012-04-01
Flooding has always been a major risk world-wide. Humans chose to live and develop settlements close to water (rivers, seas) due to the resources water brings, i.e. food, energy, capacity to economically transport persons and goods, and recreation. However, the risk from flooding, including pluvial flooding, often offsets these huge advantages. Floods sometimes have terrible consequences from both a human and economic point of view. The permanence and growth of urban areas in flood-prone zones despite these risks is a clear indication of the choices of concerned human groups. The observed growing concentration of population along the sea shore, the increase of urban population worldwide, the exponential growth of the world population and possibly climate change are factors that confirm flood will remain a major issue for the next decades. Flood management systems are designed and implemented to cope with such situations. In spite of frequent events, lessons look to be difficult to draw out and progresses are rather slow. The list of potential triggers to improve flood management systems is nevertheless well established: information, education, awareness raising, alert, prevention, protection, feedback from events, ... Many disciplines are concerned which cover a wide range of soft and hard sciences. A huge amount of both printed and electronic literature is available. Regulations are abundant. In spite of all these potentially favourable elements, similar questions spring up after each new significant event: • Was the event forecast precise enough? • Was the alert system efficient? • Why were buildings built in identified flood prone areas? • Why did the concerned population not follow instructions? • Why did the dike break? • What should we do to avoid it happens again? • What about damages evaluation, wastes and debris evacuation, infrastructures and buildings repair, activity recovery, temporary relocation of inhabitants, health concerns, insurance concerns, water-resistant materials, vulnerability assessment ? Flood resilient system (FReS) concept has been proposed as a new framework to address flood situations. Such systems intend to better approach such situations from a holistic point of view. FReS encompass ecologic, spatial, structural, social, disaster relief and flood risk aspects. FReS design and implementation conditions have been addressed by the FP7 SMARTeST (Smart Resilience Technology, Systems and Tools) project. The focus of this Project on the use of available and innovative communication, forecasting and flood protection technologies leads to an original contribution which highlights both the scope and the limits of this technology driven approach. These reflexions contribute to the elaboration of guidelines for the design of FReS.
Roy, W.R.; Chou, S.-F.J.; Krapac, I.G.
1995-01-01
Twenty retail agrichemical facilities were flooded. There was a concern that pesticide-contaminated road fill at these facilities had been transported into residential areas by the flooding. Forty fill and flood- related sediment samples were collected at six facilities. No significant accumulation of sediments was present at any of the six facilities. At five of the six facilities, it did not appear that road fill had been transported off-site. Pesticides were detected in sediment samples collected off-site adjacent to five of the facilities. Of the 21 samples collected off-site, atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazide) and metolachlor (2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)acet-o-toluidine) were detected in 86 and 81% of the samples, respectively. When compared with on-site concentrations, off-site pesticide concentrations were either at similar levels, or were as much as three orders of magnitude less. The interpretation of the pesticide data was difficult and often inconclusive, because there were no background data on the occurrence and distribution of pesticides at each site before flooding.
Septic Systems - What to Do after the Flood
Where can I find information on my septic system? Do I pump my tank during flooded or saturated drainfield conditions? What if my septic system has been used to dispose wastewater from my business? What do I do with my septic system after the flood?
Bergholz, Peter W; Strawn, Laura K; Ryan, Gina T; Warchocki, Steven; Wiedmann, Martin
2016-03-01
Although flooding introduces microbiological, chemical, and physical hazards onto croplands, few data are available on the spatial extent, patterns, and development of contamination over time postflooding. To address this paucity of information, we conducted a spatially explicit study of Escherichia coli and Salmonella contamination prevalence and genetic diversity in produce fields after the catastrophic flooding that occurred in New England during 2011. Although no significant differences were detected between the two participating farms, both random forest and logistic regression revealed changes in the spatial pattern of E. coli contamination in drag swab samples over time. Analyses also indicated that E. coli detection was associated with changes in farm management to remediate the land after flooding. In particular, E. coli was widespread in drag swab samples at 21 days postflooding, but the spatial pattern changed by 238 days postflooding such that E. coli was then most prevalent in close proximity to surface water features. The combined results of several population genetics analyses indicated that over time postflooding E. coli populations on the farms (i) changed in composition and (ii) declined overall. Salmonella was primarily detected in surface water features, but some Salmonella strains were isolated from soil and drag swab samples at 21 and 44 days postflooding. Although postflood contamination and land management responses should always be evaluated in the context of each unique farm landscape, our results provide quantitative data on the general patterns of contamination after flooding and support the practice of establishing buffer zones between flood-contaminated cropland and harvestable crops in produce fields.
Strategies for detection of floodplain inundation with multi-frequency polarimetric SAR
NASA Technical Reports Server (NTRS)
Hess, Laura L.; Melack, John M.
1992-01-01
Mapping of floodplain inundation patterns is a key element in developing hydrological and biogeochemical models for large tropical river basins such as the Amazon. Knowledge of the time sequence of inundation is necessary to determine both water routing and biogenic gas fluxes. Synthetic Aperture Radar (SAR) is uniquely suited for this application because of its ability to penetrate cloud cover and, in many cases, to detect flooding beneath a forest or herbaceous canopy. A procedure for discriminating flooded forest, flooded herbaceous vegetation, and open water from other cover types for a coastal wetland site on the lower Altamaha floodplain, Georgia, emphasizing robust classifiers that are not site-specific is currently being developed.
Rapid flood loss estimation for large scale floods in Germany
NASA Astrophysics Data System (ADS)
Schröter, Kai; Kreibich, Heidi; Merz, Bruno
2013-04-01
Rapid evaluations of flood events are needed for efficient responses both in emergency management and financial appraisal. Beyond that, closely monitoring and documenting the formation and development of flood events and their impacts allows for an improved understanding and in depth analyses of the interplay between meteorological, hydrological, hydraulic and societal causes leading to flood damage. This contribution focuses on the development of a methodology for the rapid assessment of flood events. In the first place, the focus is on the prediction of damage to residential buildings caused by large scale floods in Germany. For this purpose an operational flood event analysis system is developed. This system has basic spatial thematic data available and supports data capturing about the current flood situation. This includes the retrieval of online gauge data and the integration of remote sensing data. Further, it provides functionalities to evaluate the current flood situation, to assess the hazard extent and intensity and to estimate the current flood impact using the flood loss estimation model FLEMOps+r. The operation of the flood event analysis system will be demonstrated for the past flood event from January 2011 with a focus on the Elbe/Saale region. On this grounds, further requirements and potential for improving the information basis as for instance by including hydrological and /or hydraulic model results as well as information from social sensors will be discussed.
Murshed, Mohamad Fared; Aslam, Zeeshan; Lewis, Rosmala; Chow, Christopher; Wang, Dongsheng; Drikas, Mary; van Leeuwen, John
2014-10-01
The treatment of organics present in the lower reaches of a major river system (the Murray-Darling Basin, Australia) before (March-July 2010), during (December 2010-May 2011) and after (April-December 2012) a major flood period was investigated. The flood period (over 6months) occurred during an intense La Niña cycle, leading to rapid and high increases in river flows and organic loads in the river water. Dissolved organic carbon (DOC) increased (2-3 times) to high concentrations (up to 16mg/L) and was found to correlate with river flow rates. The treatability of organics was studied using conventional jar tests with alum and an enhanced coagulation model (mEnCo©). Predicted mean alum dose rates (per mg DOC) were higher before (9.1mg alum/mg DOC) and after (8.5mg alum/mg DOC) than during the flood event (8.0mg alum/mg DOC), indicating differences in the character of the organics in raw waters. To assess the character of natural organic matter present in raw and treated waters, high performance size exclusion chromatography with UV and fluorescence detectors were used. During the flood period, high molecular weight UV absorbing compounds (>2kDa) were mostly detected in waters collected, but were not evident in waters collected before and afterwards. The relative abundances of humic-like and protein-like compounds during and following the flood period were also investigated and found to be of a higher molecular weight during the flood period. The treatability of the organics was found to vary over the three climate conditions investigated. Copyright © 2014. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Thompson, Chris; Croke, Jacky
2016-04-01
The year 2010-2011 was the wettest on record for the state of Queensland, Australia producing catastrophic floods. A tropical low pressure system in 2013 delivered further extreme flood events across South East Queensland (SEQ) which prompted state and local governments to conduct studies into flood magnitude and frequency in the region and catchment factors contributing to flood hazards. The floods in the region are strongly influenced by El Nino-Southern Oscillation (ENSO) phenomenon, but also modulated by the Interdecadal Pacific Oscillation (IPO) which leads to flood and drought dominated regimes and high hydrological variability. One geomorphic feature in particular exerted a significant control on the transmission speed, the magnitude of flood inundation and resultant landscape resilience. This feature was referred to as a 'macrochannel', a term used to describe a 'large-channel' which has bankfull recurrence intervals generally greater than 10 years. The macrochannels display non-linear downstream hydraulic geometry which leads to zones of flood expansion (when hydraulic geometry decreases) and zones of flood contraction (when hydraulic geometry increases). The pattern of contraction and expansion zones determines flood hazard zones. The floods caused significant wet flow bank mass failures that mobilised over 1,000,000 m3 of sediment in one subcatchment. Results suggest that the wetflow bank mass failures are a stage in a cyclical evolution process which maintains the macrochannel morphology, hence channel resilience to floods. Chronological investigations further show the macrochannels are laterally stable and identify periods of heightened flood activity over the past millennium and upper limits on flood magnitude. This paper elaborates on the results of the geomorphic investigations on Lockyer Creek in SEQ and how the results have alerted managers and policy makers to the different flood responses of these systems and how flood risk management plans can be developed based on the identified hazard zones and geomorphic processes of macrochannel systems.
On the stationarity of Floods in west African rivers
NASA Astrophysics Data System (ADS)
NKA, B. N.; Oudin, L.; Karambiri, H.; Ribstein, P.; Paturel, J. E.
2014-12-01
West Africa undergoes a big change since the years 1970-1990, characterized by very low precipitation amounts, leading to low stream flows in river basins, except in the Sahelian region where the impact of human activities where pointed out to justify the substantial increase of floods in some catchments. More recently, studies showed an increase in the frequency of intense rainfall events, and according to observations made over the region, increase of flood events is also noticeable during the rainy season. Therefore, the assumption of stationarity on flood events is questionable and the reliability of flood evolution and climatic patterns is justified. In this work, we analyzed the trends of floods events for several catchments in the Sahelian and Sudanian regions of Burkina Faso. We used thirteen tributaries of large river basins (Niger, Nakambe, Mouhoun, Comoé) for which daily rainfall and flow data were collected from national hydrological and meteorological services of the country. We used Mann-Kendall and Pettitt tests to detect trends and break points in the annual time series of 8 rainfall indices and the annual maximum discharge records. We compare the trends of precipitation indices and flood size records to analyze the possible causality link between floods size and rainfall pattern. We also analyze the stationary of the frequency of flood exceeding the ten year return period level. The samples were extracted by a Peak over threshold method and the quantification of change in flood frequency was assessed by using a test developed by Lang M. (1995). The results exhibit two principal behaviors. Generally speaking, no trend is detected on catchments annual maximum discharge, but positive break points are pointed out in a group of three right bank tributaries of the Niger river that are located in the sahelian region between 300mm to 650mm. These same catchments show as well an increase of the yearly number of flood greater than the ten year flood since 1980. However, there is no consistency between rain fall pattern and flood size pattern in the entire region.
NASA Astrophysics Data System (ADS)
Neumann, Jessica; Arnal, Louise; Magnusson, Linus; Cloke, Hannah
2017-04-01
Seasonal river flow forecasts are important for many aspects of the water sector including flood forecasting, water supply, hydropower generation and navigation. In addition to short term predictions, seasonal forecasts have the potential to realise higher benefits through more optimal and consistent decisions. Their operational use however, remains a challenge due to uncertainties posed by the initial hydrologic conditions (e.g. soil moisture, groundwater levels) and seasonal climate forcings (mainly forecasts of precipitation and temperature), leading to a decrease in skill with increasing lead times. Here we present a stakeholder-led case study for the Thames catchment (UK), currently being undertaken as part of the H2020 IMPREX project. The winter of 2013-14 was the wettest on record in the UK; driven by 12 major Atlantic depressions, the Thames catchment was subject to compound (concurrent) flooding from fluvial and groundwater sources. Focusing on the 2013-14 floods, this study aims to see whether increased skill in meteorological input translates through to more accurate forecasting of compound flood events at seasonal timescales in the Thames catchment. An earlier analysis of the ECMWF System 4 (S4) seasonal meteorological forecasts revealed that it did not skilfully forecast the extreme event of winter 2013-14. This motivated the implementation of an atmospheric experiment by the ECMWF to force the S4 to more accurately represent the low-pressure weather conditions prevailing in winter 2013-14 [1]. Here, we used both the standard and the "improved" S4 seasonal meteorological forecasts to force the EFAS (European Flood Awareness System) LISFLOOD hydrological model. Both hydrological forecasts were started on the 1st of November 2013 and run for 4 months of lead time to capture the peak of the 2013-14 flood event. Comparing the seasonal hydrological forecasts produced with both meteorological forcing data will enable us to assess how the improved meteorology translates into skill in the hydrological forecast for this extreme compound event. As primary stakeholders involved in the study, the Environment Agency and Flood Forecasting Centre are responsible for managing flood risk in the UK. For them, the detection of a potential flood signal weeks or months in advance could be of great value in terms of operational practice, decision-making and early warning. [1] Rodwell, M.J., Ferranti, L., Magnusson, L., Weisheimer, A., Rabier, F. & Richardson, D. (2015) Diagnosis of northern hemispheric regime behaviour during winter 2013/14. ECMWF Technical Memoranda 769.
Yanosky, Thomas M.
1983-01-01
Ash trees along the Potomac River flood plain near Washington, D.C., were studied to determine changes in wood anatomy related to flood damage, and anomalous growth was compared to flood records for April 15 to August 31, 1930-79. Collectively, anatomical evidence was detected for 33 of the 34 growing-season floods during the study period. Evidence of 12 floods prior to 1930 was also noted, including catastrophic ones in 1889 and 1924. Trees damaged after the transition from earlywood to latewood growth typically formed ' flood rings ' of enlarged vessels within the latewood zone. Trees damaged near the beginning of the growth year developed flood rings within, or contiguous with, the earlywood. Both patterns are assumed to have developed when flood-damaged trees produced a second crop of leaves. Trees damaged by high-magnitude floods developed well formed flood rings along the entire height and around the entire circumference of the stem. Small floods were generally associated wtih diffuse or discontinuous anomalies restricted to stem apices. Frequency of flood rings was positively related to flood magnitude, and time of flood generation during the tree-growth season was estimated from the radial position of anomalous growth relative to annual ring width. Reconstructing tree heights in a year of flood-ring formation gives a minimum stage estimate along local stream reaches. Some trees provided evidence of numerous floods. Those with the greatest number of flood rings grew on frequently flooded surfaces subject to flood-flow velocities of at least 1 m/s, and more typically greater than 2 m/s. Tree size, more than age, was related to flood-ring formation. Trees kept small by frequent flood damage had more flood rings than taller trees of comparable age. (USGS)
NASA Technical Reports Server (NTRS)
Wu, Huan; Adler, Robert F.; Tian, Yudong; Huffman, George J.; Li, Hongyi; Wang, JianJian
2014-01-01
A widely used land surface model, the Variable Infiltration Capacity (VIC) model, is coupled with a newly developed hierarchical dominant river tracing-based runoff-routing model to form the Dominant river tracing-Routing Integrated with VIC Environment (DRIVE) model, which serves as the new core of the real-time Global Flood Monitoring System (GFMS). The GFMS uses real-time satellite-based precipitation to derive flood monitoring parameters for the latitude band 50 deg. N - 50 deg. S at relatively high spatial (approximately 12 km) and temporal (3 hourly) resolution. Examples of model results for recent flood events are computed using the real-time GFMS (http://flood.umd.edu). To evaluate the accuracy of the new GFMS, the DRIVE model is run retrospectively for 15 years using both research-quality and real-time satellite precipitation products. Evaluation results are slightly better for the research-quality input and significantly better for longer duration events (3 day events versus 1 day events). Basins with fewer dams tend to provide lower false alarm ratios. For events longer than three days in areas with few dams, the probability of detection is approximately 0.9 and the false alarm ratio is approximately 0.6. In general, these statistical results are better than those of the previous system. Streamflow was evaluated at 1121 river gauges across the quasi-global domain. Validation using real-time precipitation across the tropics (30 deg. S - 30 deg. N) gives positive daily Nash-Sutcliffe Coefficients for 107 out of 375 (28%) stations with a mean of 0.19 and 51% of the same gauges at monthly scale with a mean of 0.33. There were poorer results in higher latitudes, probably due to larger errors in the satellite precipitation input.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Huan; Adler, Robert F.; Tian, Yudong
2014-03-01
A widely used land surface model, the Variable Infiltration Capacity (VIC) model, is coupled with a newly developed hierarchical dominant river tracing-based runoff-routing model to form the Dominant river tracing-Routing Integrated with VIC Environment (DRIVE) model, which serves as the new core of the real-time Global Flood Monitoring System (GFMS). The GFMS uses real-time satellite-based precipitation to derive flood monitoring parameters for the latitude band 50°N–50°S at relatively high spatial (~12 km) and temporal (3 hourly) resolution. Examples of model results for recent flood events are computed using the real-time GFMS (http://flood.umd.edu). To evaluate the accuracy of the new GFMS,more » the DRIVE model is run retrospectively for 15 years using both research-quality and real-time satellite precipitation products. Evaluation results are slightly better for the research-quality input and significantly better for longer duration events (3 day events versus 1 day events). Basins with fewer dams tend to provide lower false alarm ratios. For events longer than three days in areas with few dams, the probability of detection is ~0.9 and the false alarm ratio is ~0.6. In general, these statistical results are better than those of the previous system. Streamflow was evaluated at 1121 river gauges across the quasi-global domain. Validation using real-time precipitation across the tropics (30°S–30°N) gives positive daily Nash-Sutcliffe Coefficients for 107 out of 375 (28%) stations with a mean of 0.19 and 51% of the same gauges at monthly scale with a mean of 0.33. Finally, there were poorer results in higher latitudes, probably due to larger errors in the satellite precipitation input.« less
Flood Resilient Systems and their Application for Flood Resilient Planning
NASA Astrophysics Data System (ADS)
Manojlovic, N.; Gabalda, V.; Antanaskovic, D.; Gershovich, I.; Pasche, E.
2012-04-01
Following the paradigm shift in flood management from traditional to more integrated approaches, and considering the uncertainties of future development due to drivers such as climate change, one of the main emerging tasks of flood managers becomes the development of (flood) resilient cities. It can be achieved by application of non-structural - flood resilience measures, summarised in the 4As: assistance, alleviation, awareness and avoidance (FIAC, 2007). As a part of this strategy, the key aspect of development of resilient cities - resilient built environment can be reached by efficient application of Flood Resilience Technology (FReT) and its meaningful combination into flood resilient systems (FRS). FRS are given as [an interconnecting network of FReT which facilitates resilience (including both restorative and adaptive capacity) to flooding, addressing physical and social systems and considering different flood typologies] (SMARTeST, http://www.floodresilience.eu/). Applying the system approach (e.g. Zevenbergen, 2008), FRS can be developed at different scales from the building to the city level. Still, a matter of research is a method to define and systematise different FRS crossing those scales. Further, the decision on which resilient system is to be applied for the given conditions and given scale is a complex task, calling for utilisation of decision support tools. This process of decision-making should follow the steps of flood risk assessment (1) and development of a flood resilience plan (2) (Manojlovic et al, 2009). The key problem in (2) is how to match the input parameters that describe physical&social system and flood typology to the appropriate flood resilient system. Additionally, an open issue is how to integrate the advances in FReT and findings on its efficiency into decision support tools. This paper presents a way to define, systematise and make decisions on FRS at different scales of an urban system developed within the 7th FP Project SMARTeST. A web based three tier advisory system FLORETO-KALYPSO (http://floreto.wb.tu-harburg.de/, Manojlovic et al, 2009) devoted to support decision-making process at the building level has been further developed to support multi-scale decision making on resilient systems, improving the existing data mining algorithms of the Business Logic tier. Further tuning of the algorithms is to be performed based on the new developments and findings in applicability and efficiency of different FRe Technology for different flood typologies. The first results obtained at the case studies in Greater Hamburg, Germany indicate the potential of this approach to contribute to the multiscale resilient planning on the road to flood resilient cities. FIAC (2007): "Final report form the Awareness and Assistance Sub-committee", FIAC, Scottish Government Zevenbergen C. et al (2008) "Challenges in urban flood management: travelling across spatial and temporal scales", Journal of FRM Volume 1 Issue 2, p 81-88 Manojlovic N., et al (2009): "Capacity Building in FRM through a DSS Utilising Data Mining Approach", Proceed. 8th HIC, Concepcion, Chile, January, 2009
Design of flood early warning system with wifi network based on smartphone
NASA Astrophysics Data System (ADS)
Supani, Ahyar; Andriani, Yuli; Taqwa, Ahmad
2017-11-01
Today, the development using internet of things enables activities surrounding us to be monitored, controlled, predicted and calculated remotely through connections to the internet network such as monitoring activities of long-distance flood warning with information technology. Applying an information technology in the field of flood early warning has been developed in the world, either connected to internet network or not. The internet network that has been done in this paper is the design of WiFi network to access data of rainfall, water level and flood status at any time with a smartphone coming from flood early warning system. The results obtained when test of data accessing with smartphone are in form of rainfall and water level graphs against time and flood status indicators consisting of 3 flood states: Standby 2, Standby 1 and Flood. It is concluded that data are from flood early warning system has been able to accessed and displayed on smartphone via WiFi network in any time and real time.
Quantifying the Impact of Floods on Bacillary Dysentery in Dalian City, China, From 2004 to 2010.
Xu, Xin; Ding, Guoyong; Zhang, Ying; Liu, Zhidong; Liu, Qiyong; Jiang, Baofa
2017-04-01
Studies quantifying relationships between floods and diarrheal diseases have mainly been conducted in low-latitude regions. It's therefore increasingly important to examine these relationships in midlatitude regions, where they may have significant public health implications. This study aimed to examine the association between floods and bacillary dysentery in the city of Dalian, China. A generalized additive mixed model was applied to examine the association between floods and bacillary dysentery. The relative risk (RR) of flood impact on bacillary dysentery was estimated. A total of 18,976 cases of bacillary dysentery were reported in Dalian during the study period. Two weeks' lagged effect was detected from the impact of floods on bacillary dysentery. The RR of flood impact on bacillary dysentery was 1.17 (95% CI: 1.03-1.33). Floods have significantly increased the risk of bacillary dysentery in Dalian. More studies should focus on the association between floods and infectious diseases in different regions. Our findings have significant implications for managing the negative health impact of floods in the midlatitude region of China. (Disaster Med Public Health Preparedness. 2017;11:190-195).
Proteomic and Biochemical Analyses of the Cotyledon and Root of Flooding-Stressed Soybean Plants
Komatsu, Setsuko; Makino, Takahiro; Yasue, Hiroshi
2013-01-01
Background Flooding significantly reduces the growth and grain yield of soybean plants. Proteomic and biochemical techniques were used to determine whether the function of cotyledon and root is altered in soybean under flooding stress. Results Two-day-old soybean plants were flooded for 2 days, after which the proteins from root and cotyledon were extracted for proteomic analysis. In response to flooding stress, the abundance of 73 and 28 proteins was significantly altered in the root and cotyledon, respectively. The accumulation of only one protein, 70 kDa heat shock protein (HSP70) (Glyma17g08020.1), increased in both organs following flooding. The ratio of protein abundance of HSP70 and biophoton emission in the cotyledon was higher than those detected in the root under flooding stress. Computed tomography and elemental analyses revealed that flooding stress decreases the number of calcium oxalate crystal the cotyledon, indicating calcium ion was elevated in the cotyledon under flooding stress. Conclusion These results suggest that calcium might play one role through HSP70 in the cotyledon under flooding stress. PMID:23799004
Environment Agency England flood warning systems
NASA Astrophysics Data System (ADS)
Strong, Chris; Walters, Mark; Haynes, Elizabeth; Dobson, Peter
2015-04-01
Context In England around 5 million homes are at risk of flooding. We invest significantly in flood prevention and management schemes but we can never prevent all flooding. Early alerting systems are fundamental to helping us reduce the impacts of flooding. The Environment Agency has had the responsibility for flood warning since 1996. In 2006 we invested in a new dissemination system that would send direct messages to pre-identified recipients via a range of channels. Since then we have continuously improved the system and service we offer. In 2010 we introduced an 'opt-out' service where we pre-registered landline numbers in flood risk areas, significantly increasing the customer base. The service has performed exceptionally well under intense flood conditions. Over a period of 3 days in December 2013, when England was experiencing an east coast storm surge, the system sent nearly 350,000 telephone messages, 85,000 emails and 70,000 text messages, with a peak call rate of around 37,000 per hour and 100% availability. The Floodline Warnings Direct (FWD) System FWD provides warnings in advance of flooding so that people at risk and responders can take action to minimise the impact of the flood. Warnings are sent via telephone, fax, text message, pager or e-mail to over 1.1 million properties located within flood risk areas in England. Triggers for issuing alerts and warnings include attained and forecast river levels and rainfall in some rapidly responding locations. There are three levels of warning: Flood Alert, Flood Warning and Severe Flood Warning, and a stand down message. The warnings can be updated to include relevant information to help inform those at risk. Working with our current provider Fujitsu, the system is under a programme of continuous improvement including expanding the 'opt-out' service to mobile phone numbers registered to at risk addresses, allowing mobile registration to the system for people 'on the move' and providing access to registration via third parties. The 'Future Flood Warning System' Our research shows that people want more choice on how they access and receive warnings. Many want a service tailored to their own risk, rather than that of their community. They also want more information about the forecast and the situation to that they can make decisions personal to their circumstances. Our future flood warning system will build upon the success of our existing service and will aim to: • provide our customers with a more flexible and personalised self-service approach which caters for the diverse range of user needs • alert people wherever they are, not just in properties • be flexible enough to respond to user feedback to make improvements and utilise new technology as it becomes available • provide real-time visualisation of system performance, to assist our flood response • capture greater levels of information from the recipients of our warnings • be efficient for operators of the system and utilise automation where relevant • take a risk based approach to resilience to provide the highest level of reliability when needed at a reduced cost
Musser, Jonathan W.
2018-01-31
Digital flood-inundation maps for a 12.6-mile reach of the Withlacoochee River from Skipper Bridge Road to St. Augustine Road (Georgia State Route 133) were developed to depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey (USGS) streamgage at Withlacoochee River at Skipper Bridge Road, near Bemiss, Ga. (023177483). Real-time stage information from this streamgage can be used with these maps to estimate near real-time areas of inundation. The forecasted peak-stage information for the USGS streamgage at Withlacoochee River at Skipper Bridge Road, near Bemiss, Ga. (023177483), can be used in conjunction with the maps developed for this study to show predicted areas of flood inundation.A one-dimensional step-backwater model was developed using the U.S. Army Corps of Engineers Hydrologic Engineer-ing Center’s River Analysis System (HEC–RAS) software for the Withlacoochee River and was used to compute flood profiles for a 12.6-mile reach of the Withlacoochee River. The hydraulic model was then used to simulate 23 water-surface profiles at 1.0-foot (ft) intervals at the Withlacoochee River near the Bemiss streamgage. The profiles ranged from the National Weather Service action stage of 10.7 ft, which is 131.0 ft above the North American Vertical Datum of 1988 (NAVD 88), to a stage of 32.7 ft, which is 153.0 ft above NAVD 88. The simulated water-surface profiles were then combined with a geographic information system digital elevation model—derived from light detection and ranging (lidar) data having a 4.0-ft horizontal resolution—to delineate the area flooded at each 1.0-ft interval of stream stage.
Ledien, Julia; Sorn, Sopheak; Hem, Sopheak; Huy, Rekol; Buchy, Philippe
2017-01-01
Remote sensing can contribute to early warning for diseases with environmental drivers, such as flooding for leptospirosis. In this study we assessed whether and which remotely-sensed flooding indicator could be used in Cambodia to study any disease for which flooding has already been identified as an important driver, using leptospirosis as a case study. The performance of six potential flooding indicators was assessed by ground truthing. The Modified Normalized Difference Water Index (MNDWI) was used to estimate the Risk Ratio (RR) of being infected by leptospirosis when exposed to floods it detected, in particular during the rainy season. Chi-square tests were also calculated. Another variable—the time elapsed since the first flooding of the year—was created using MNDWI values and was also included as explanatory variable in a generalized linear model (GLM) and in a boosted regression tree model (BRT) of leptospirosis infections, along with other explanatory variables. Interestingly, MNDWI thresholds for both detecting water and predicting the risk of leptospirosis seroconversion were independently evaluated at -0.3. Value of MNDWI greater than -0.3 was significantly related to leptospirosis infection (RR = 1.61 [1.10–1.52]; χ2 = 5.64, p-value = 0.02, especially during the rainy season (RR = 2.03 [1.25–3.28]; χ2 = 8.15, p-value = 0.004). Time since the first flooding of the year was a significant risk factor in our GLM model (p-value = 0.042). These results suggest that MNDWI may be useful as a risk indicator in an early warning remote sensing tool for flood-driven diseases like leptospirosis in South East Asia. PMID:28704461
Ledien, Julia; Sorn, Sopheak; Hem, Sopheak; Huy, Rekol; Buchy, Philippe; Tarantola, Arnaud; Cappelle, Julien
2017-01-01
Remote sensing can contribute to early warning for diseases with environmental drivers, such as flooding for leptospirosis. In this study we assessed whether and which remotely-sensed flooding indicator could be used in Cambodia to study any disease for which flooding has already been identified as an important driver, using leptospirosis as a case study. The performance of six potential flooding indicators was assessed by ground truthing. The Modified Normalized Difference Water Index (MNDWI) was used to estimate the Risk Ratio (RR) of being infected by leptospirosis when exposed to floods it detected, in particular during the rainy season. Chi-square tests were also calculated. Another variable-the time elapsed since the first flooding of the year-was created using MNDWI values and was also included as explanatory variable in a generalized linear model (GLM) and in a boosted regression tree model (BRT) of leptospirosis infections, along with other explanatory variables. Interestingly, MNDWI thresholds for both detecting water and predicting the risk of leptospirosis seroconversion were independently evaluated at -0.3. Value of MNDWI greater than -0.3 was significantly related to leptospirosis infection (RR = 1.61 [1.10-1.52]; χ2 = 5.64, p-value = 0.02, especially during the rainy season (RR = 2.03 [1.25-3.28]; χ2 = 8.15, p-value = 0.004). Time since the first flooding of the year was a significant risk factor in our GLM model (p-value = 0.042). These results suggest that MNDWI may be useful as a risk indicator in an early warning remote sensing tool for flood-driven diseases like leptospirosis in South East Asia.
Flood disaster risk assessment of rural housings--a case study of Kouqian Town in China.
Zhang, Qi; Zhang, Jiquan; Jiang, Liupeng; Liu, Xingpeng; Tong, Zhijun
2014-04-03
Floods are a devastating kind of natural disaster. About half of the population in China lives in rural areas. Therefore, it is necessary to assess the flood disaster risk of rural housings. The results are valuable for guiding the rescue and relief goods layout. In this study, we take the severe flood disaster that happened at Kouqian Town in Jilin, China in 2010 as an example to build an risk assessment system for flood disaster on rural housings. Based on the theory of natural disaster risk formation and "3S" technology (remote sensing, geography information systems and global positioning systems), taking the rural housing as the bearing body, we assess the flood disaster risk from three aspects: hazard, exposure and vulnerability. The hazard presented as the flood submerging range and depth. The exposure presented as the values of the housing and the property in it. The vulnerability presented as the relationship between the losses caused by flood and flood depth. We validate the model by the field survey after the flood disaster. The risk assessment results highly coincide with the field survey losses. This model can be used to assess the risk of other flood events in this area.
An experimental system for flood risk forecasting and monitoring at global scale
NASA Astrophysics Data System (ADS)
Dottori, Francesco; Alfieri, Lorenzo; Kalas, Milan; Lorini, Valerio; Salamon, Peter
2017-04-01
Global flood forecasting and monitoring systems are nowadays a reality and are being applied by a wide range of users and practitioners in disaster risk management. Furthermore, there is an increasing demand from users to integrate flood early warning systems with risk based forecasting, combining streamflow estimations with expected inundated areas and flood impacts. Finally, emerging technologies such as crowdsourcing and social media monitoring can play a crucial role in flood disaster management and preparedness. Here, we present some recent advances of an experimental procedure for near-real time flood mapping and impact assessment. The procedure translates in near real-time the daily streamflow forecasts issued by the Global Flood Awareness System (GloFAS) into event-based flood hazard maps, which are then combined with exposure and vulnerability information at global scale to derive risk forecast. Impacts of the forecasted flood events are evaluated in terms of flood prone areas, potential economic damage, and affected population, infrastructures and cities. To increase the reliability of our forecasts we propose the integration of model-based estimations with an innovative methodology for social media monitoring, which allows for real-time verification and correction of impact forecasts. Finally, we present the results of preliminary tests which show the potential of the proposed procedure in supporting emergency response and management.
Looking at flood trends with different eyes: the value of a fuzzy flood classification scheme
NASA Astrophysics Data System (ADS)
Sikorska, A. E.; Viviroli, D.; Brunner, M. I.; Seibert, J.
2016-12-01
Natural floods can be governed by several processes such as heavy rainfall or intense snow- or glacier-melt. These processes result in different flood characteristics in terms of flood shape and magnitude. Pooling floods of different types might therefore impair the analyses of flood frequencies and trends. Thus, the categorization of flood events into different flood type classes and the determination of their respective frequencies is essential for a better understanding and for the prediction of floods. In reality however most flood events are caused by a mix of processes and a unique determination of a flood type per event often becomes difficult. This study proposes an innovative method for a more reliable categorization of floods according to similarities in flood drivers. The categorization of floods into subgroups relies on a fuzzy decision tree. While the classical (crisp) decision tree allows for the identification of only one flood type per event, the fuzzy approach enables the detection of mixed types. Hence, events are represented as a spectrum of six possible flood types, while a degree of acceptance attributed to each of them specifies the importance of each type during the event formation. Considered types are flash, short rainfall, long rainfall, snow-melt, rainfall-on-snow, and, in high altitude watersheds, also glacier-melt floods. The fuzzy concept also enables uncertainty present in the identification of flood processes and in the method to be incorporated into the flood categorization process. We demonstrate, for a set of nine Swiss watersheds and 30 years of observations, that this new concept provides more reliable flood estimates than the classical approach as it allows for a more dedicated flood prevention technique adapted to a specific flood type.
Flood-inundation maps for the Meramec River at Valley Park and at Fenton, Missouri, 2017
Dietsch, Benjamin J.; Sappington, Jacob N.
2017-09-29
Two sets of digital flood-inundation map libraries that spanned a combined 16.7-mile reach of the Meramec River that extends upstream from Valley Park, Missouri, to downstream from Fenton, Mo., were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Army Corps of Engineers, St. Louis Metropolitan Sewer District, Missouri Department of Transportation, Missouri American Water, and Federal Emergency Management Agency Region 7. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the cooperative USGS streamgages on the Meramec River at Valley Park, Mo., (USGS station number 07019130) and the Meramec River at Fenton, Mo. (USGS station number 07019210). Near-real-time stage data at these streamgages may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at these sites (listed as NWS sites vllm7 and fnnm7, respectively).Flood profiles were computed for the stream reaches by means of a calibrated one-dimensional step-backwater hydraulic model. The model was calibrated using a stage-discharge relation at the Meramec River near Eureka streamgage (USGS station number 07019000) and documented high-water marks from the flood of December 2015 through January 2016.The calibrated hydraulic model was used to compute two sets of water-surface profiles: one set for the streamgage at Valley Park, Mo. (USGS station number 07019130), and one set for the USGS streamgage on the Meramec River at Fenton, Mo. (USGS station number 07019210). The water-surface profiles were produced for stages at 1-foot (ft) intervals referenced to the datum from each streamgage and ranging from the NWS action stage, or near bankfull discharge, to the stage corresponding to the estimated 0.2-percent annual exceedance probability (500-year recurrence interval) flood, as determined at the Eureka streamgage (USGS station number 07019000). The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.28-ft vertical accuracy and 3.28-ft horizontal resolution) to delineate the area flooded at each flood stage (water level).The availability of these maps, along with internet information regarding current stage from the USGS streamgages and forecasted high-flow stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures and for postflood recovery efforts.
Flood Warning and Forecasting System in Slovakia
NASA Astrophysics Data System (ADS)
Leskova, Danica
2016-04-01
In 2015, it finished project Flood Warning and Forecasting System (POVAPSYS) as part of the flood protection in Slovakia till 2010. The aim was to build POVAPSYS integrated computerized flood forecasting and warning system. It took a qualitatively higher level of output meteorological and hydrological services in case of floods affecting large territorial units, as well as local flood events. It is further unfolding demands on performance and coordination of meteorological and hydrological services, troubleshooting observation, evaluation of data, fast communication, modeling and forecasting of meteorological and hydrological processes. Integration of all information entering and exiting to and from the project POVAPSYS provides Hydrological Flood Forecasting System (HYPOS). The system provides information on the current hydrometeorological situation and its evolution with the generation of alerts and notifications in case of exceeding predefined thresholds. HYPOS's functioning of the system requires flawless operability in critical situations while minimizing the loss of its key parts. HYPOS is a core part of the project POVAPSYS, it is a comprehensive software solutions based on a modular principle, providing data and processed information including alarms, in real time. In order to achieve full functionality of the system, in proposal, we have put emphasis on reliability, robustness, availability and security.
[Study on influence of floods on bacillary dysentery incidence in Liaoning province, 2004 -2010].
Xu, X; Liu, Z D; Han, D B; Xu, Y Q; Jiang, B F
2016-05-01
To understand the influence of floods on bacillary dysentery in Liaoning province. The monthly surveillance data of bacillary dysentery, floods, meteorological and demographic data in Liaoning from 2004 to 2010 were collected. Panel Poisson regression analysis was conducted to evaluate the influence of floods on the incidence of bacillary dysentery in Liaoning. The mean monthly morbidity of bacillary dysentery was 2.17 per 100 000 during the study period, the bacillary dysentery cases mainly occurred in during July-September. Spearman correlation analysis showed that no lagged effect was detected in the influence of floods on the incidence of bacillary dysentery. After adjusting the influence of meteorological factors, panel data analysis showed that the influence of floods on the incidence of bacillary dysentery existed and the incidence rate ratio was 1.439 4(95%CI: 1.408 1-1.471 4). Floods could significantly increase the risk of bacillary dysentery for population in Liaoning.
Varying effects of geomorphic change on floodplain inundation and forest communities
NASA Astrophysics Data System (ADS)
Keim, R.; Johnson, E. L.; Edwards, B. L.; King, S. L.; Hupp, C. R.
2015-12-01
Overbank flooding in floodplains is an important control on vegetation, but effects of changing flooding are difficult to predict because sensitivities of plant communities to multidimensional flooding (frequency, depth, duration, and timing) are not well understood. We used HEC-RAS to model the changing flooding regime in the lower White River floodplain, Arkansas, in response to rapid incision of the Mississippi River in the 1930s, and quantified flood frequency, depth, and duration by forest community type. Incision has decreased flooding especially in terms of frequency, which is one of the most important variables for ecological processes. Modeled depth-duration curves varied more among floodplain reaches than among forest communities within the same reach, but forest communities are now arranged in accordance with new flood regimes in place after river incision. Forest responses to subtle geomorphic change are slower than other vegetation communities, so detection of the full ramifications of ecohydrologic change may require decades.
Increasing risk of great floods in a changing climate
Milly, P.C.D.; Wetherald, R.T.; Dunne, K.A.; Delworth, T.L.
2002-01-01
Radiative effects of anthropogenic changes in atmospheric composition are expected to cause climate changes, in particular an intensification of the global water cycle with a consequent increase in flood risk. But the detection of anthropogenically forced changes in flooding is difficult because of the substantial natural variability; the dependence of streamflow trends on flow regime further complicates the issue. Here we investigate the changes in risk of great floods - that is, floods with discharges exceeding 100-year levels from basins larger than 200,000 km2 - using both streamflow measurements and numerical simulations of the anthropogenic climate change associated with greenhouse gases and direct radiative effects of sulphate aerosols. We find that the frequency of great floods increased substantially during the twentieth century. The recent emergence of a statistically significant positive trend in risk of great floods is consistent with results from the climate model, and the model suggests that the trend will continue.
NASA Astrophysics Data System (ADS)
Li, Jiren; Yesou, Herve; Malosti, Rita; Andreoli, Remi; Huang, Shifeng; Xin, Jingfeng; Cattaneo, Fabrizia
2008-04-01
The Flood Dragon project enhances the Envisat contribution for natural disaster monitoring. Flood DFRAGON project had much more exploited the ENVISAT resource for crisis management than the International Charter Space and major Disasters since 2002. Indeed, during the 2005, 2006 and 2007 Chinese flood seasons, over the 27 attempted NRT exploitations of Envisat, 23 were successful. Obtained results over floods, affecting Yangtze and Songua, Huaihe watersheds as pollution events on Taihue lake and Nen River are illustrated. Lessons are discussed in terms of programming, downloading, processing, and images type and format. Recommendations for the background mission of the future Sentinel 1 constellation are given.
NASA Astrophysics Data System (ADS)
Mirosław-Świątek, Dorota; Grygoruk, Mateusz
2016-04-01
Temporal, volumetric and areal trends of flooding remain dominant factors shaping habitat conditions of riparian wetlands. In contemporary Europe, where the pristine extent of riparian wetlands strongly decreased due to antropopression and the flow regime of majority of rivers was decently modified in agricultural and hydropower purposes, valuable riparian habitats that remained in good ecological state require appropriate maintenance of floods. Even though multiple environmental regulations were implemented worldwide in order to mitigate negative effects of antropopression to flow regime and habitats, it is the climatic change that challenges riparian ecosystem management to the extent comparable (if not higher) than the direct human interventions. Wishing to detect probable influence of the ongoing climatic change on the flood regime one should search for catchment systems of a low antropopression, where the long term variability of flood extents, flood depths and recurrence intervals are likely to reflect climatic changes rather than human activity. In our study we analysed 60-years long time series of the discharge data of Biebrza river (NE Poland) that was found in numerous studies a reference in a temperate-continental European riparian and mire ecosystem research. Daily data of river discharge was used as boundary conditions in the WETFLOD - a developed integrated river-floodplain-groundwater flow model applied to the environment of Lower Biebrza Basin. The model was used to simulate and analyze trends of changes in flood extent and water depths in selected, well preserved vegetation patches namely the Caricetum appropinquatae, Caricetum gracilis, Phragmitetum communis and Glycerietum maximae. Temporal trends were analysed on the basis of distribution deciles of flood extents, depths and recurrence intervals. Study revealed that flood extents and flood depths in the first decade of the 21st century were decently different from the ones modeled for the second part of the 20th century. This is considered a challenge for habitat management as the most recent hydrological dynamics of these riparian habitats entail different temporal balance of oxic-anoxic conditions.
Designing Flood Management Systems for Joint Economic and Ecological Robustness
NASA Astrophysics Data System (ADS)
Spence, C. M.; Grantham, T.; Brown, C. M.; Poff, N. L.
2015-12-01
Freshwater ecosystems across the United States are threatened by hydrologic change caused by water management operations and non-stationary climate trends. Nonstationary hydrology also threatens flood management systems' performance. Ecosystem managers and flood risk managers need tools to design systems that achieve flood risk reduction objectives while sustaining ecosystem functions and services in an uncertain hydrologic future. Robust optimization is used in water resources engineering to guide system design under climate change uncertainty. Using principles introduced by Eco-Engineering Decision Scaling (EEDS), we extend robust optimization techniques to design flood management systems that meet both economic and ecological goals simultaneously across a broad range of future climate conditions. We use three alternative robustness indices to identify flood risk management solutions that preserve critical ecosystem functions in a case study from the Iowa River, where recent severe flooding has tested the limits of the existing flood management system. We seek design modifications to the system that both reduce expected cost of flood damage while increasing ecologically beneficial inundation of riparian floodplains across a wide range of plausible climate futures. The first robustness index measures robustness as the fraction of potential climate scenarios in which both engineering and ecological performance goals are met, implicitly weighting each climate scenario equally. The second index builds on the first by using climate projections to weight each climate scenario, prioritizing acceptable performance in climate scenarios most consistent with climate projections. The last index measures robustness as mean performance across all climate scenarios, but penalizes scenarios with worse performance than average, rewarding consistency. Results stemming from alternate robustness indices reflect implicit assumptions about attitudes toward risk and reveal the tradeoffs between using structural and non-structural flood management strategies to ensure economic and ecological robustness.
44 CFR 61.12 - Rates based on a flood protection system involving Federal funds.
Code of Federal Regulations, 2013 CFR
2013-10-01
... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program INSURANCE COVERAGE AND RATES § 61.12 Rates based on a flood protection system involving... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Rates based on a flood...
44 CFR 61.12 - Rates based on a flood protection system involving Federal funds.
Code of Federal Regulations, 2010 CFR
2010-10-01
... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program INSURANCE COVERAGE AND RATES § 61.12 Rates based on a flood protection system involving... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Rates based on a flood...
44 CFR 61.12 - Rates based on a flood protection system involving Federal funds.
Code of Federal Regulations, 2014 CFR
2014-10-01
... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program INSURANCE COVERAGE AND RATES § 61.12 Rates based on a flood protection system involving... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Rates based on a flood...
44 CFR 61.12 - Rates based on a flood protection system involving Federal funds.
Code of Federal Regulations, 2011 CFR
2011-10-01
... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program INSURANCE COVERAGE AND RATES § 61.12 Rates based on a flood protection system involving... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Rates based on a flood...
44 CFR 61.12 - Rates based on a flood protection system involving Federal funds.
Code of Federal Regulations, 2012 CFR
2012-10-01
... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program INSURANCE COVERAGE AND RATES § 61.12 Rates based on a flood protection system involving... 44 Emergency Management and Assistance 1 2012-10-01 2011-10-01 true Rates based on a flood...
Detection and attribution of flood change across the United States
NASA Astrophysics Data System (ADS)
Archfield, Stacey
2017-04-01
In the United States, there have a been an increasing number of studies quantifying trends in the annual maximum flood; yet, few studies examine trends in floods that may occur more than once in a given year and even fewer assess trends in floods on rivers that have undergone substantial changes due to urbanization, land-cover change, and agricultural drainage practices. Previous research has shown that, for streamgages having minimal direct human intervention, trends in the peak magnitude, frequency, duration and volume of frequent floods (floods occurring at an average of two events per year relative to a base period) across the United States show large changes; however, few trends are found to be statistically significant. This study extends previous research to provide a comprehensive assessment of flood change across the United States that includes streamgages having experienced confounding alterations to streamflow (urbanization, storage, and land-cover changes) that provides a comprehensive assessment of flood change. Attribution of these changes is also explored.
Has dyke development in the Vietnamese Mekong Delta shifted flood hazard downstream?
NASA Astrophysics Data System (ADS)
Van Khanh Triet, Nguyen; Viet Dung, Nguyen; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko
2017-08-01
In the Vietnamese part of the Mekong Delta (VMD) the areas with three rice crops per year have been expanded rapidly during the last 15 years. Paddy-rice cultivation during the flood season has been made possible by implementing high-dyke flood defenses and flood control structures. However, there are widespread claims that the high-dyke system has increased water levels in downstream areas. Our study aims at resolving this issue by attributing observed changes in flood characteristics to high-dyke construction and other possible causes. Maximum water levels and duration above the flood alarm level are analysed for gradual trends and step changes at different discharge gauges. Strong and robust increasing trends of peak water levels and duration downstream of the high-dyke areas are found with a step change in 2000/2001, i.e. immediately after the disastrous flood which initiated the high-dyke development. These changes are in contrast to the negative trends detected at stations upstream of the high-dyke areas. This spatially different behaviour of changes in flood characteristics seems to support the public claims. To separate the impact of the high-dyke development from the impact of the other drivers - i.e. changes in the flood hydrograph entering the Mekong Delta, and changes in the tidal dynamics - hydraulic model simulations of the two recent large flood events in 2000 and 2011 are performed. The hydraulic model is run for a set of scenarios whereas the different drivers are interchanged. The simulations reveal that for the central VMD an increase of 9-13 cm in flood peak and 15 days in duration can be attributed to high-dyke development. However, for this area the tidal dynamics have an even larger effect in the range of 19-32 cm. However, the relative contributions of the three drivers of change vary in space across the delta. In summary, our study confirms the claims that the high-dyke development has raised the flood hazard downstream. However, it is not the only and not the most important driver of the observed changes. It has to be noted that changes in tidal levels caused by sea level rise in combination with the widely observed land subsidence and the temporal coincidence of high water levels and spring tides have even larger impacts. It is recommended to develop flood risk management strategies using the high-dyke areas as retention zones to mitigate the flood hazard downstream.
The Evaluation of Foam Performance and Flooding Efficiency
NASA Astrophysics Data System (ADS)
Keliang, Wang; Yuhao, Chen; Gang, Wang; Gen, Li
2017-12-01
ROSS-Miles and spinning drop interfacial tensionmeter are used to select suitable foam system through foam composite index (FCI) and interfacial tension (IT). The selected foam system are taken to conduct further test. The further tests are evaluating the foam system resistance to adsorption with multi-round core flooding dynamic adsorption test and evaluating the performance of foam system with four kinds of different transport distance, quantitatively analyzing the foam system effective distance after dynamic adsorption. The result shows that the foaming ability and the mobilizing ability of the foam system decrease with the increase of the round of dynamic adsorption. As the transport distance increases, the foaming ability and the mobilizing ability of the foam system decrease. This result further reveals the flooding characteristics of nitrogen foam flooding, which provides a reference for the implementation of nitrogen foam flooding technology.
44 CFR 64.3 - Flood Insurance Maps.
Code of Federal Regulations, 2011 CFR
2011-10-01
... flood hazard that results from the decertification of a previously accredited flood protection system that is determined to be in the process of being restored to provide base flood protection V Area of... tidal floods (coastal high hazard area) V1-30, VE Area of special flood hazards, with water surface...
Preliminary Cost Benefit Assessment of Systems for Detection of Hazardous Weather. Volume I,
1981-07-01
not be sufficient for adequate stream flow forecasting , it has important potential for real - time flash flood warning. This was illustrated by the 1977...provide a finer spatial resolution of the gridded data. See Table 9. 42 The results of a demonstration of the real - time capabilities of a radar-man system ...detailed real time measurement capabilities and scope for quantitative forecasting is most likely to provide the degree of lead time required if maximum
Applications of ASFCM(Assessment System of Flood Control Measurement) in Typhoon Committee Members
NASA Astrophysics Data System (ADS)
Kim, C.
2013-12-01
Due to extreme weather environment such as global warming and greenhouse effect, the risks of having flood damage has been increased with larger scale of flood damages. Therefore, it became necessary to consider modifying climate change, flood damage and its scale to the previous dimension measurement evaluation system. In this regard, it is needed to establish a comprehensive and integrated system to evaluate the most optimized measures for flood control through eliminating uncertainties of socio-economic impacts. Assessment System of Structural Flood Control Measures (ASFCM) was developed for determining investment priorities of the flood control measures and establishing the social infrastructure projects. ASFCM consists of three modules: 1) the initial setup and inputs module, 2) the flood and damage estimation module, and 3) the socio-economic analysis module. First, we have to construct the D/B for flood damage estimation, which is the initial and input data about the estimation unit, property, historical flood damages, and applied area's topographic & hydrological data. After that, it is important to classify local characteristic for constructing flood damage data. Five local characteristics (big city, medium size city, small city, farming area, and mountain area) are classified by criterion of application (population density). Next step is the floodplain simulation with HEC-RAS which is selected to simulate inundation. Through inputting the D/B and damage estimation, it is able to estimate the total damage (only direct damage) that is the amount of cost to recover the socio-economic activities back to the safe level before flood did occur. The last module suggests the economic analysis index (B/C ratio) with Multidimensional Flood Damage Analysis. Consequently, ASFCM suggests the reference index in constructing flood control measures and planning non-structural systems to reduce water-related damage. It is possible to encourage flood control planners and managers to consider and apply the socio-economic analysis results. ASFCM was applied in Republic of Korea, Thailand and Philippines to review efficiency and applicability. Figure 1. ASFCM Application(An-yang Stream, Republic of Korea)
The dynamics of human-water systems: comparing observations and simulations
NASA Astrophysics Data System (ADS)
Di Baldassarre, G.; Ciullo, A.; Castellarin, A.; Viglione, A.
2016-12-01
Real-word data of human-flood interactions are compared to the results of stylized socio-hydrological models. These models build on numerous examples from different parts of the world and consider two main prototypes of floodplain systems. Green systems, whereby societies cope with flood risk via non-structural measures, e.g. resettling out of floodplain areas ("living with floods" approach); and Technological systems, whereby societies cope with flood risk by also via structural measures, e.g. building levees ("fighting floods" approach). The floodplain systems of the Tiber River in Rome and the Ganges-Brahmaputra-Meghna Rivers in Bangladesh systems are used as case studies. The comparison of simulations and observations shows the potential of socio-hydrological models in capturing the dynamics of risk emerging from the interactions and feedbacks between social and hydrological processes, such as learning and forgetting effects. It is then discussed how the proposed approach can contribute to a better understanding of flood risk changes and therefore support the process of disaster risk reduction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collins, E.K.
1979-08-01
Three separate reviews of the Turkey Point Units 3 and 4 were conducted by the FPLCO between 1972 and 1975. Initially, at the request of NBC in 1972, the FPLCO reviewed several water systems as sources of flooding. Subsequently, as a result of an abnormal occurrence, the drainage system was reviewed. Finally, the facilities were again reviewed at NRC's request and both the potential sources of flooding and safety-related equipment which could be damaged by flooding were identified. The sources of flooding and the appropriate safety equipment are discussed. An evaluation is presented of measures that were taken by FPLCOmore » to minimize the danger of flooding and to protect safety-related equipment.« less
NASA Astrophysics Data System (ADS)
Zhang, B.; Koirala, R.; Oliver-Cabrera, T.; Wdowinski, S.; Osmanoglu, B.
2017-12-01
Hurricanes can cause winds, rainfall and storm surge, all of which could result in flooding. Between August and September 2017, Hurricanes Harvey, Irma and Maria made landfall over Texas, Florida and Puerto Rico causing destruction and damages. Flood mapping is important for water management and to estimate risks and property damage. Though water gauges are able to monitor water levels, they are normally distributed sparsely. To map flooding products of these extreme events, we use Synthetic Aperture Radar (SAR) observations acquired by the European satellite constellation Sentinel-1. We obtained two acquisitions from before each flooding event, a single acquisition during the hurricane, and two after each event, a total of five acquisitions. We use both amplitude and phase observations to map extent and magnitude of flooding respectively. To map flooding extents, we use amplitude images from before, after and if possible during the hurricane pass. A calibration is used to convert the image raw data to backscatter coefficient, termed sigma nought. We generate a composite of the two image layers using red and green bands to show the change of sigma nought between acquisitions, which directly reflects the extent of flooding. Because inundation can result with either an increase or decrease of sigma nought values depending on the surface scattering characteristics, we map flooded areas in location where sigma nought changes were above a detection threshold. To study magnitude of flooding we study Interferometric Synthetic Aperture Radar (InSAR) phase changes. Changes in the water level can be detected by the radar when the signal is reflected away from water surface and bounces again by another object (e.g. trees and/or buildings) known as double bounce phase. To generate meaningful interferograms, we compare phase information with the nearest water gauge records to verify our results. Preliminary results show that the three hurricanes caused flooding condition over wide area including both rural and urban areas. The flooding in Everglades National Park in Florida following hurricane Irma covered area 1087.35 km2. Flooding in Puerto Rico main island was limited to low flat areas covering 287.84 km2. Preliminary results of the InSAR analysis shows that flooding magnitude reached in some location level of 1 m.
Global Rapid Flood Mapping System with Spaceborne SAR Data
NASA Astrophysics Data System (ADS)
Yun, S. H.; Owen, S. E.; Hua, H.; Agram, P. S.; Fattahi, H.; Liang, C.; Manipon, G.; Fielding, E. J.; Rosen, P. A.; Webb, F.; Simons, M.
2017-12-01
As part of the Advanced Rapid Imaging and Analysis (ARIA) project for Natural Hazards, at NASA's Jet Propulsion Laboratory and California Institute of Technology, we have developed an automated system that produces derived products for flood extent map generation using spaceborne SAR data. The system takes user's input of area of interest polygons and time window for SAR data search (pre- and post-event). Then the system automatically searches and downloads SAR data, processes them to produce coregistered SAR image pairs, and generates log amplitude ratio images from each pair. Currently the system is automated to support SAR data from the European Space Agency's Sentinel-1A/B satellites. We have used the system to produce flood extent maps from Sentinel-1 SAR data for the May 2017 Sri Lanka floods, which killed more than 200 people and displaced about 600,000 people. Our flood extent maps were delivered to the Red Cross to support response efforts. Earlier we also responded to the historic August 2016 Louisiana floods in the United States, which claimed 13 people's lives and caused over $10 billion property damage. For this event, we made synchronized observations from space, air, and ground in close collaboration with USGS and NOAA. The USGS field crews acquired ground observation data, and NOAA acquired high-resolution airborne optical imagery within the time window of +/-2 hours of the SAR data acquisition by JAXA's ALOS-2 satellite. The USGS coordinates of flood water boundaries were used to calibrate our flood extent map derived from the ALOS-2 SAR data, and the map was delivered to FEMA for estimating the number of households affected. Based on the lessons learned from this response effort, we customized the ARIA system automation for rapid flood mapping and developed a mobile friendly web app that can easily be used in the field for data collection. Rapid automatic generation of SAR-based global flood maps calibrated with independent observations from ground, air, and space will provide reliable snapshot extent of many flooding events. SAR missions with easy data access, such as the Sentinel-1 and NASA's upcoming NISAR mission, combined with the ARIA system, will enable forming a library of flood extent maps, which can soon support flood modeling community, by providing observation-based constraints.
RF-CLASS: A Remote-sensing-based Interoperable Web service system for Flood Crop Loss Assessment
NASA Astrophysics Data System (ADS)
Di, L.; Yu, G.; Kang, L.
2014-12-01
Flood is one of the worst natural disasters in the world. Flooding often causes significant crop loss over large agricultural areas in the United States. Two USDA agencies, the National Agricultural Statistics Service (NASS) and Risk Management Agency (RMA), make decisions on flood statistics, crop insurance policy, and recovery management by collecting, analyzing, reporting, and utilizing flooded crop acreage and crop loss information. NASS has the mandate to report crop loss after all flood events. RMA manages crop insurance policy and uses crop loss information to guide the creation of the crop insurance policy and the aftermath compensation. Many studies have been conducted in the recent years on monitoring floods and assessing the crop loss due to floods with remote sensing and geographic information technologies. The Remote-sensing-based Flood Crop Loss Assessment Service System (RF-CLASS), being developed with NASA and USDA support, aims to significantly improve the post-flood agricultural decision-making supports in USDA by integrating and advancing the recently developed technologies. RF-CLASS will operationally provide information to support USDA decision making activities on collecting and archiving flood acreage and duration, recording annual crop loss due to flood, assessing the crop insurance rating areas, investigating crop policy compliance, and spot checking of crop loss claims. This presentation will discuss the remote sensing and GIS based methods for deriving the needed information to support the decision making, the RF-CLASS cybersystem architecture, the standards and interoperability arrangements in the system, and the current and planned capabilities of the system.
Yin, Xiaojian; Hiraga, Susumu; Hajika, Makita; Nishimura, Minoru; Komatsu, Setsuko
2017-03-01
Soybean is highly sensitive to flooding stress and exhibits markedly reduced plant growth and grain yield under flooding conditions. To explore the mechanisms underlying initial flooding tolerance in soybean, RNA sequencing-based transcriptomic analysis was performed using a flooding-tolerant line and ABA-treated soybean. A total of 31 genes included 12 genes that exhibited similar temporal patterns were commonly changed in these plant groups in response to flooding and they were mainly involved in RNA regulation and protein metabolism. The mRNA expression of matrix metalloproteinase, glucose-6-phosphate isomerase, ATPase family AAA domain-containing protein 1, and cytochrome P450 77A1 was up-regulated in wild-type soybean under flooding conditions; however, no changes were detected in the flooding-tolerant line or ABA-treated soybean. The mRNA expression of cytochrome P450 77A1 was specifically up-regulated in root tips by flooding stress, but returned to the level found in control plants following treatment with the P450 inhibitor uniconazole. The survival ratio and root fresh weight of plants were markedly improved by 3-h uniconazole treatment under flooding stress. Taken together, these results suggest that cytochrome P450 77A1 is suppressed by uniconazole treatment and that this inhibition may enhance soybean tolerance to flooding stress.
Detecting seasonal flood changes in the Upper Danube River basin
NASA Astrophysics Data System (ADS)
Kohnová, Silvia; Jeneiová, Katarína; Parajka, Juraj; Hall, Julia; Marková, Romana
2017-04-01
Due to a number of large-scale floods observed worldwide in recent years, the analysis of changes in long-term hydrological time series is becoming increasingly important. This study focuses on the Upper Danube region, which was struck by many flood events in the past decade. The flood seasonality of the study region, defined as the area of Germany, the Czech Republic, Switzerland, Austria and Slovakia, is examined to interpret the dominant flood processes. A spatial assessment of the seasonality indices of the annual maximum discharges and the seasonal discharges (derived from daily average discharges) was conducted for 117 gauging stations. Hot spots for potential changes in the mean dates of occurrence of the discharges were identified, and the results were linked with derived spatial characteristics for the catchments. The first results of the study of the seasonal discharges revealed that the variability of occurrence of summer floods is higher than winter floods in lowlands of the upper Danube catchment. In high Alpine catchments the winter floods variability of occurrence is the same or higher than for the summer floods. The summer season floods tend to appear for all catchment sizes in the same time period. With increased magnitude of floods in the summer season, the variability of occurrence of the floods is higher.
Mhuantong, Wuttichai; Wongwilaiwalin, Sarunyou; Laothanachareon, Thanaporn; Eurwilaichitr, Lily; Tangphatsornruang, Sithichoke; Boonchayaanant, Benjaporn; Limpiyakorn, Tawan; Pattaragulwanit, Kobchai; Punmatharith, Thantip; McEvoy, John; Khan, Eakalak; Rachakornkij, Manaskorn; Champreda, Verawat
2015-01-01
The Thailand flood crisis in 2011 was one of the largest recorded floods in modern history, causing enormous damage to the economy and ecological habitats of the country. In this study, bacterial and fungal diversity in sediments and waters collected from ten flood areas in Bangkok and its suburbs, covering residential and agricultural areas, were analyzed using high-throughput 454 pyrosequencing of 16S rRNA gene and internal transcribed spacer sequences. Analysis of microbial community showed differences in taxa distribution in water and sediment with variations in the diversity of saprophytic microbes and sulfate/nitrate reducers among sampling locations, suggesting differences in microbial activity in the habitats. Overall, Proteobacteria represented a major bacterial group in waters, while this group co-existed with Firmicutes, Bacteroidetes, and Actinobacteria in sediments. Anaeromyxobacter, Steroidobacter, and Geobacter were the dominant bacterial genera in sediments, while Sulfuricurvum, Thiovirga, and Hydrogenophaga predominated in waters. For fungi in sediments, Ascomycota, Glomeromycota, and Basidiomycota, particularly in genera Philipsia, Rozella, and Acaulospora, were most frequently detected. Chytridiomycota and Ascomycota were the major fungal phyla, and Rhizophlyctis and Mortierella were the most frequently detected fungal genera in water. Diversity of sulfate-reducing bacteria, related to odor problems, was further investigated using analysis of the dsrB gene which indicated the presence of sulfate-reducing bacteria of families Desulfobacteraceae, Desulfobulbaceae, Syntrobacteraceae, and Desulfoarculaceae in the flood sediments. The work provides an insight into the diversity and function of microbes related to biological processes in flood areas.
NASA Astrophysics Data System (ADS)
Kaur, K.; Laanearu, J.; Annus, I.
2017-10-01
The numerical experiments are carried out for qualitative and quantitative interpretation of a multi-phase flow processes associated with malfunctioning of the Tallinn storm-water system during rain storms. The investigations are focused on the single-line inverted siphon, which is used as under-road connection of pipes of the storm-water system under interest. A multi-phase flow solver of Computational Fluid Dynamics software OpenFOAM is used for simulating the three-phase flow dynamics in the hydraulic system. The CFD simulations are performed with different inflow rates under same initial conditions. The computational results are compared essentially in two cases 1) design flow rate and 2) larger flow rate, for emptying the initially filled inverted siphon from a slurry-fluid. The larger flow-rate situations are under particular interest to detected possible flooding. In this regard, it is anticipated that the CFD solutions provide an important insight to functioning of inverted siphon under a restricted water-flow conditions at simultaneous presence of air and slurry-fluid.
NASA Astrophysics Data System (ADS)
Pingel, N.; Liang, Y.; Bindra, A.
2016-12-01
More than 1 million Californians live and work in the floodplains of the Sacramento-San Joaquin Valley where flood risks are among the highest in the nation. In response to this threat to people, property and the environment, the Department of Water Resources (DWR) has been called to action to improve flood risk management. This has transpired through significant advances in development of flood information and tools, analysis, and planning. Senate Bill 5 directed DWR to prepare the Central Valley Flood Protection Plan (CVFPP) and update it every 5 years. A key component of this aggressive planning approach is answering the question: What is the current flood risk, and how would proposed improvements change flood risk throughout the system? Answering this question is a substantial challenge due to the size and complexity of the watershed and flood control system. The watershed is roughly 42,000 sq mi, and flows are controlled by numerous reservoirs, bypasses, and levees. To overcome this challenge, the State invested in development of a comprehensive analysis "tool box" through various DWR programs. Development of the tool box included: collection of hydro-meteorological, topographic, geotechnical, and economic data; development of rainfall-runoff, reservoir operation, hydraulic routing, and flood risk analysis models; and development of specialized applications and computing schemes to accelerate the analysis. With this toolbox, DWR is analyzing flood hazard, flood control system performance, exposure and vulnerability of people and property to flooding, consequence of flooding for specific events, and finally flood risk for a range of CVFPP alternatives. Based on the results, DWR will put forward a State Recommended Plan in the 2017 CVFPP. Further, the value of the analysis tool box extends beyond the CVFPP. It will serve as a foundation for other flood studies for years to come and has already been successfully applied for inundation mapping to support emergency response, reservoir operation analysis, and others.
NASA Astrophysics Data System (ADS)
Kiss, Andrea; Laszlovszky, József
2014-05-01
In the present paper an overview of published and unpublished results of archaeological and sedimentary investigations, predominantly reflect on 14th-16th-century changes, are provided and compared to documentary information on flood events and long-term changes. Long-term changes in flood behaviour and average water-level conditions had long-term detectable impacts on sedimentation and fluvio-morphological processes. Moreover, the available archaeological evidence might also provide information on the reaction of the society, in the form of changes in settlement organisation, building structures and processes. At present, information is mainly available concerning the 16th, and partly to the 14th-15th centuries. Medium and short term evidence mainly corresponds to the main flood peaks or even to single catastrophic flood events. Such processes may be identified in archaeological evidence concerning the second half of the 14th, early 15th centuries; while most of the cases listed above were connected to the flood peak (and/or generally increasing water-level conditions) of the late 15th and early 16th centuries. In other cases connections between sedimentary/archaeological evidence and the mid- and late 16th-century high flood-frequency period were presumed. Documentary evidence referring to the same period suggests that higher flood frequency and intensity periods occurred in the early and mid 16th century; a probably more prolonged flood rich period took place in the second half of the 16th century, with a peak in the late 1560s-early 1570s and maybe with another at the end of the 16th century. Earlier flood peaks in documentary evidence were detected on the Danube at the turn of the 14th-15th centuries and in the last decades of the 15th century, continuing in the early 16th century.
Else, Mark A; Taylor, June M; Atkinson, Christopher J
2006-01-01
In flooded soils, the rapid effects of decreasing oxygen availability on root metabolic activity are likely to generate many potential chemical signals that may impact on stomatal apertures. Detached leaf transpiration tests showed that filtered xylem sap, collected at realistic flow rates from plants flooded for 2 h and 4 h, contained one or more factors that reduced stomatal apertures. The closure could not be attributed to increased root output of the glucose ester of abscisic acid (ABA-GE), since concentrations and deliveries of ABA conjugates were unaffected by soil flooding. Although xylem sap collected from the shoot base of detopped flooded plants became more alkaline within 2 h of flooding, this rapid pH change of 0.5 units did not alter partitioning of root-sourced ABA sufficiently to prompt a transient increase in xylem ABA delivery. More shoot-sourced ABA was detected in the xylem when excised petiole sections were perfused with pH 7 buffer, compared with pH 6 buffer. Sap collected from the fifth oldest leaf of "intact" well-drained plants and plants flooded for 3 h was more alkaline, by approximately 0.4 pH units, than sap collected from the shoot base. Accordingly, xylem [ABA] was increased 2-fold in sap collected from the fifth oldest petiole compared with the shoot base of flooded plants. However, water loss from transpiring, detached leaves was not reduced when the pH of the feeding solution containing 3-h-flooded [ABA] was increased from 6.7 to 7.1 Thus, the extent of the pH-mediated, shoot-sourced ABA redistribution was not sufficient to raise xylem [ABA] to physiologically active levels. Using a detached epidermis bioassay, significant non-ABA anti-transpirant activity was also detected in xylem sap collected at intervals during the first 24 h of soil flooding.
Study of the impact of cyclogenesis at the Mediterranean Sea
NASA Astrophysics Data System (ADS)
Ribo, M.; Llasat, C.
2009-09-01
The Mediterranean Basin is usually affected by high impact weather events, generating high impacts in all Mediterranean countries and causing important damages. This basin is surrounded by mountains and arid regions, and the interaction of the air flow with the orography barriers produces many effects, the most important is the formation of low pressure centers. This is one of the reasons why the Mediterranean Sea is considered to be the most cyclogenetic area in the world (Jansà, 1997). Floods are also one of the most important natural hazards in the Mediterranean Basin. Flood events occur when soil absorption, runoff or drainage cannot adequately disperse intense rainfall from quasi-stationary or stationary weather systems in short time periods. In some occasions these floods produce high social impact in the affected areas. Our work presents the study of the relationship between the flood episodes and the presence of cyclones in the Mediterranean Basin during those episodes, between 1990 and 2004. Information about social impact of each event has also been considered. To do these analyses the MEDEX database (MEDiterranean EXperiment on cyclones that produce high impact weather in the Mediterranean) has been improved in the frame work of the European FLASH project, and information about cyclones and rainfall has been extracted from the MEDEX cyclones database. A total of 217 flood events had been identified. Once the presence of one or more cyclones during each flood episode has been identified, temporal and regional analyses were made to determine the distribution of the cyclonic centers and to study the evolution of the events. Mediterranean cyclogenesis is leaded by influence of external systems (along the African coast, from the Atlantic Ocean, and from the west of Europe), although the majority of the cyclones (87% of the studied cases) are generated in the Mediterranean Basin, under influence of preexistent systems. There are different Mediterranean cyclones, from weak mesoscale depressions to strong, intense and more extensive depressions, and are classified using different criteria. In our study each cyclone identified was characterized using two dynamic criteria: vertical structure and geostrophic circulation. The first characterization is based on the vertical profiles of the laplacian of temperature, depending on which atmospheric level is reached by the cyclone. The second characterization is based on the geostrophic circulation, defined with the geostrophic vorticity in the cyclone domain. From these two characterizations, we have classified the cyclonic centers into six different types: deep, medium and shallow; strong, moderate and weak cyclones. Results show that between 1990 and 2004, 25% of the days in this time period have recorded a flood event in the Mediterranean Basin, and 90.7% of these flood events were related to a cyclonic center. 57% of these events had been located at the western Mediterranean part, although some flood prone areas can be identified in all the Mediterranean Basin; Eastern Spain and Balearic Islands, northern of Italy (gulf of Genève), north of Africa (Sahara) and Cyprus and Turkey. Cyclones related with floods in the western part are mainly superficial cyclones. An important nucleus of deep cyclones related with floods can be found near Cyprus. The spatial distribution of cyclones related with floods, for the period from 1990 to 2004, is coherent with the general distribution of cyclones showed by Gil et al. 2002. There is a general tendency of increase of detected flood events with cyclonic center in the vicinity in the time period analyzed. A total of 4724 victims where counted during flood episodes. Results of the relationship between flood episodes and cyclonic centers show that 40% of the flood episodes with higher damages were related to weak cyclones.
Development of a flood-induced health risk prediction model for Africa
NASA Astrophysics Data System (ADS)
Lee, D.; Block, P. J.
2017-12-01
Globally, many floods occur in developing or tropical regions where the impact on public health is substantial, including death and injury, drinking water, endemic disease, and so on. Although these flood impacts on public health have been investigated, integrated management of floods and flood-induced health risks is technically and institutionally limited. Specifically, while the use of climatic and hydrologic forecasts for disaster management has been highlighted, analogous predictions for forecasting the magnitude and impact of health risks are lacking, as is the infrastructure for health early warning systems, particularly in developing countries. In this study, we develop flood-induced health risk prediction model for African regions using season-ahead flood predictions with climate drivers and a variety of physical and socio-economic information, such as local hazard, exposure, resilience, and health vulnerability indicators. Skillful prediction of flood and flood-induced health risks can contribute to practical pre- and post-disaster responses in both local- and global-scales, and may eventually be integrated into multi-hazard early warning systems for informed advanced planning and management. This is especially attractive for areas with limited observations and/or little capacity to develop flood-induced health risk warning systems.
Thorndahl, Søren; Nielsen, Jesper Ellerbæk; Jensen, David Getreuer
2016-12-01
Flooding produced by high-intensive local rainfall and drainage system capacity exceedance can have severe impacts in cities. In order to prepare cities for these types of flood events - especially in the future climate - it is valuable to be able to simulate these events numerically, both historically and in real-time. There is a rather untested potential in real-time prediction of urban floods. In this paper, radar data observations with different spatial and temporal resolution, radar nowcasts of 0-2 h leadtime, and numerical weather models with leadtimes up to 24 h are used as inputs to an integrated flood and drainage systems model in order to investigate the relative difference between different inputs in predicting future floods. The system is tested on the small town of Lystrup in Denmark, which was flooded in 2012 and 2014. Results show it is possible to generate detailed flood maps in real-time with high resolution radar rainfall data, but rather limited forecast performance in predicting floods with leadtimes more than half an hour.
76 FR 17019 - List of Approved Spent Fuel Storage Casks: HI-STORM Flood/Wind Addition
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-28
... Storage Casks: HI-STORM Flood/Wind Addition AGENCY: Nuclear Regulatory Commission. ACTION: Direct final... regulations to add the HI-STORM Flood/Wind cask system to the ``List of Approved Spent Fuel Storage Casks... cask designs. Discussion This rule will add the Holtec HI-STORM Flood/Wind (FW) cask system to the list...
NASA Astrophysics Data System (ADS)
Sanders, B. F.
2017-12-01
Flooding of coastal and fluvial systems are the most significant natural hazards facing society, and damages have been escalating for decades globally and in the U.S. Almost all metropolitan areas are exposed to flood risk. The threat from river flooding is especially high in India and China, and coastal cities around the world are threatened by storm surge and rising sea levels. Several trends including rising sea levels, urbanization, deforestation, and rural-to-urban population shifts will increase flood exposure in the future. Flood impacts are escalating despite advances in hazards science and extensive effort to manage risks. The fundamental issue is not that flooding is becoming more severe, even though it is in some places, but rather that societies are become more vulnerable to flood impacts. A critical factor contributing to the escalation of flood impacts is that the most vulnerable sectors of communities are left out of processes to prepare for and respond to flooding. Furthermore, the translation of knowledge about flood hazards and vulnerabilities into actionable information for communities has not been effective. In Southern and Baja California, an interdisciplinary team of researchers has partnered with stakeholders in flood vulnerable communities to co-develop flood hazard information systems designed to meet end-user needs for decision-making. The initiative leveraged the power of advanced, fine-scale hydraulic models of flooding to craft intuitive visualizations of context-sensitive scenarios. This presentation will cover the ways by which the process of flood inundation modeling served as a focal point for knowledge development, as well as the unique visualizations that populate on-line information systems accessible here: http://floodrise.uci.edu/online-flood-hazard-viewers/
Flood Disaster Risk Assessment of Rural Housings — A Case Study of Kouqian Town in China
Zhang, Qi; Zhang, Jiquan; Jiang, Liupeng; Liu, Xingpeng; Tong, Zhijun
2014-01-01
Floods are a devastating kind of natural disaster. About half of the population in China lives in rural areas. Therefore, it is necessary to assess the flood disaster risk of rural housings. The results are valuable for guiding the rescue and relief goods layout. In this study, we take the severe flood disaster that happened at Kouqian Town in Jilin, China in 2010 as an example to build an risk assessment system for flood disaster on rural housings. Based on the theory of natural disaster risk formation and “3S” technology (remote sensing, geography information systems and global positioning systems), taking the rural housing as the bearing body, we assess the flood disaster risk from three aspects: hazard, exposure and vulnerability. The hazard presented as the flood submerging range and depth. The exposure presented as the values of the housing and the property in it. The vulnerability presented as the relationship between the losses caused by flood and flood depth. We validate the model by the field survey after the flood disaster. The risk assessment results highly coincide with the field survey losses. This model can be used to assess the risk of other flood events in this area. PMID:24705363
The link between land use and flood risk assessment in urban areas
NASA Astrophysics Data System (ADS)
Sörensen, Johanna; Kalantari, Zahra
2017-04-01
Densification of urban areas rises a concern for increased pluvial flooding. Flood risk in urban areas might rise under impact of land use changes. Urbanisation involves conversion of natural areas to impermeable areas giving lower infiltration rates and increased runoff. When high-intense rainfall excess the capacity of the drainage system in a city, high runoff causes pluvial flooding in low-laying areas. In the present study, a long time series (20 years) of geo-referenced flood claims from property owners has been collected and analysed in detail to assess flood risk under impact of land use changes in urban areas. The flood claim data come from property owners with flood insurance that covers property loss from overland flooding, groundwater intrusion through basement walls, as well as flooding from the drainage system, and are used as a proxy for flood severity. The spatial relationships between land use change and flood occurrences in different urban areas were analysed. Special emphasis were put on how nature-based solutions and blue-green infrastructure relates to flood risk. The relationships defined by a statistical method explaining the tendencies where the land use change contributes to flood risk changes and others engaged factors.
Flood and Landslide Applications of High Time Resolution Satellite Rain Products
NASA Technical Reports Server (NTRS)
Adler, Robert F.; Hong, Yang; Huffman, George J.
2006-01-01
Experimental, potentially real-time systems to detect floods and landslides related to heavy rain events are described. A key basis for these applications is high time resolution satellite rainfall analyses. Rainfall is the primary cause for devastating floods across the world. However, in many countries, satellite-based precipitation estimation may be the best source of rainfall data due to insufficient ground networks and absence of data sharing along many trans-boundary river basins. Remotely sensed precipitation from the NASA's TRMM Multi-satellite Precipitation Analysis (TMPA) operational system (near real-time precipitation at a spatial-temporal resolution of 3 hours and 0.25deg x 0.25deg) is used to monitor extreme precipitation events. Then these data are ingested into a macro-scale hydrological model which is parameterized using spatially distributed elevation, soil and land cover datasets available globally from satellite remote sensing. Preliminary flood results appear reasonable in terms of location and frequency of events, with implementation on a quasi-global basis underway. With the availability of satellite rainfall analyses at fine time resolution, it has also become possible to assess landslide risk on a near-global basis. Early results show that landslide occurrence is closely associated with the spatial patterns and temporal distribution of TRMM rainfall characteristics. Particularly, the number of landslides triggered by rainfall is related to rainfall climatology, antecedent rainfall accumulation, and intensity-duration of rainstorms. For the purpose of prediction, an empirical TMPA-based rainfall intensity-duration threshold is developed and shown to have skill in determining potential areas of landslides. These experimental findings, in combination with landslide surface susceptibility information based on satellite-based land surface information, form a starting point towards a potential operational landslide monitoring/warning system around the globe.
NASA Astrophysics Data System (ADS)
Wan, X. Y.
2017-12-01
The extensive constructions of reservoirs change the hydrologic characteristics of the associated watersheds, which obviously increases the complexity of watershed flood control decisions. By evaluating the impacts of the multi-reservoir system on the flood hydrograph, it becomes possible to improve the effectiveness of the flood control decisions. In this paper we compare the non-reservoir flood hydrograph with the actual observed flood hydrograph using the Lutaizi upstream of Huai river in East China as a representative case, where 20 large-scale/large-sized reservoirs have been built. Based on the total impact of the multi-reservoir system, a novel strategy, namely reservoir successively added (RSA) method, is presented to evaluate the contribution of each reservoir to the total impact. According each reservoir contribution, the "highly effective" reservoirs for watershed flood control are identified via hierarchical clustering. Moreover, we estimate further the degree of impact of the reservoir current operation rules on the flood hydrograph on the base of the impact of dams themselves. As a result, we find that the RSA method provides a useful method for analysis of multi-reservoir systems by partitioning the contribution of each reservoir to the total impacts on the flooding at the downstream section. For all the historical large floods examined, the multi-reservoir system in the Huai river watershed has a significant impact on flooding at the downstream Lutaizi section, on average reducing the flood volume and peak discharge by 13.92 × 108 m3 and 18.7% respectively. It is more informative to evaluate the maximum impact of each reservoir (on flooding at the downstream section) than to examine the average impact. Each reservoir has a different impact on the flood hydrograph at the Lutaizi section. In particular, the Meishan, Xianghongdian, Suyahu, Nanwan, Nianyushan and Foziling reservoirs exert a strong influence on the flood hydrograph, and are therefore important for flood control on the Huai river. Under the current operation rules, the volume and peak discharge of flooding at the Lutaizi section are reduced by 13.69 × 108m3 and 1429 m3/s respectively, accounting for 98% and 80.5% of the real reduction respectively.
Geographical information system (GIS) application for flood prediction at Sungai Sembrong
NASA Astrophysics Data System (ADS)
Kamin, Masiri; Ahmad, Nor Farah Atiqah; Razali, Siti Nooraiin Mohd; Hilaham, Mashuda Mohamad; Rahman, Mohamad Abdul; Ngadiman, Norhayati; Sahat, Suhaila
2017-10-01
The occurrence of flood is one of natural disaster that often beset Malaysia. The latest incident that happened in 2007 was the worst occurrence of floods ever be set in Johor. Reporting floods mainly focused on rising water rising levels, so about once a focus on the area of flood delineation. A study focused on the effectiveness of using Geographic Information System (GIS) to predict the flood by taking Sg. Sembrong, Batu Pahat, Johor as study area. This study combined hydrological model and water balance model in the display to show the expected flood area for future reference. The minimum, maximum and average rainfall data for January 2007 at Sg Sembrong were used in this study. The data shows that flood does not occurs at the minimum and average rainfall of 17.2mm and 2mm respectively. At maximum rainfall, 203mm, shows the flood area was 9983 hectares with the highest level of the water depth was 2m. The result showed that the combination of hydrological models and water balance model in GIS is very suitable to be used as a tool to obtain preliminary information on flood immediately. Besides that, GIS system is a very powerful tool used in hydrology engineering to help the engineer and planner to imagine the real situation of flood events, doing flood analysis, problem solving and provide a rational, accurate and efficient decision making.
NASA Astrophysics Data System (ADS)
Alberola, Armando; Barriendos, Mariano; Gil-Guirado, Salvador; Pérez-Morales, Alfredo; Balasch, Carles; Castelltort, Xavier; Mazón, Jordi; Pino, David; Lluís Ruiz-Bellet, Josep; Tuset, Jordi
2016-04-01
Historical flood data series of Eastern Spanish Coast (14th-20th centuries). Improving identification of climatic patterns and human factors of flood events from primary documentary sources Armando Alberola, Barriendos, M., Gil-Guirado, S., Pérez Morales, A., Balasch, C., Castelltort, X., Mazón, J., Pino, D., Ruiz-Bellet, J.L., Tuset, J. Historical flood events in eastern spanish coast have been studied by different research groups and projects. Complexity of flood processes, involving atmospheric, surface and human factors, is not easily understandable when long time series are required. Present analysis from PREDIFLOOD Project Consortium defines a new step of flood event databases: Improved access to primary (documentary) and secondary (bibliographical) sources, data collection for all possible locations where floods are detected, and improved system of classification (Barriendos et al., 2014). A first analysis is applied to 8 selected flood series. Long chronologies from PREDIFLOOD Project for Catalonia region (Girona, Barcelona, Tarragona, Lleida, Tortosa). In addition, to cover all sector of spanish mediterranean coast, we introduce Valencia city in Turia River basin. South Eastern sector is cover with Murcia and Caravaca cities, Segura River basin. Extension of area under study required contributions of research teams experienced in work of documentary primary sources (Alberola, 2006; Gil-Guirado, 2013). Flood frequency analysis for long scale periods show natural climatic oscillations into so-called Little Ice Age. There are general patterns, affecting most of basins, but also some local anomalies or singularities. To explain these differences and analogies it is not enough to use purely climatic factors. In this way, we analyze human factors that have been able to influence the variability of floods along last 6 centuries (demography, hydraulic infrastructures, urban development...). This approach improves strongly understanding of mechanisms producing major flood events on Eastern coast of Iberian Peninsula, with identification and evaluation of natural and human factors involved on that. References: Alberola, A. 2006. "Entre la sequía y la inundación. Una aproximación a las avenidas históricas de los ríos valencianos durante el siglo XVIII", in Gérard Chastagnaret and Antonio Gil Olcina (eds.), Riesgo de inundaciones en el Mediterráneo occidental, Casa de Velázquez-Universidad de Alicante, p. 1-30. ISBN 84-95555-89-1. Barriendos, M., Ruiz-Bellet, J.L., Tuset, J., Mazón, J., Balasch, C., Pino, D., Ayala, J.L.: 2014, "The 'Prediflood' database of historical floods in Catalonia (NE Iberian Peninsula) AD 1035-2013, and its potential applications in flood analysis", Hydrology and Earth System Sciences, 18: 1-17. DOI: 10.5194/hess-18-1-2014. Gil-Guirado, S.: 2013. Reconstrucción climática histórica y análisis evolutivo de la vulnerabilidad y adaptación a las sequías e inundaciones en la Cuenca del Segura (España) y en la Cuenca del Río Mendoza (Argentina). Doctoral dissertation. Universidad de Murcia, Murcia, España.
Flood impacts on a water distribution network
NASA Astrophysics Data System (ADS)
Arrighi, Chiara; Tarani, Fabio; Vicario, Enrico; Castelli, Fabio
2017-12-01
Floods cause damage to people, buildings and infrastructures. Water distribution systems are particularly exposed, since water treatment plants are often located next to the rivers. Failure of the system leads to both direct losses, for instance damage to equipment and pipework contamination, and indirect impact, since it may lead to service disruption and thus affect populations far from the event through the functional dependencies of the network. In this work, we present an analysis of direct and indirect damages on a drinking water supply system, considering the hazard of riverine flooding as well as the exposure and vulnerability of active system components. The method is based on interweaving, through a semi-automated GIS procedure, a flood model and an EPANET-based pipe network model with a pressure-driven demand approach, which is needed when modelling water distribution networks in highly off-design conditions. Impact measures are defined and estimated so as to quantify service outage and potential pipe contamination. The method is applied to the water supply system of the city of Florence, Italy, serving approximately 380 000 inhabitants. The evaluation of flood impact on the water distribution network is carried out for different events with assigned recurrence intervals. Vulnerable elements exposed to the flood are identified and analysed in order to estimate their residual functionality and to simulate failure scenarios. Results show that in the worst failure scenario (no residual functionality of the lifting station and a 500-year flood), 420 km of pipework would require disinfection with an estimated cost of EUR 21 million, which is about 0.5 % of the direct flood losses evaluated for buildings and contents. Moreover, if flood impacts on the water distribution network are considered, the population affected by the flood is up to 3 times the population directly flooded.
12 CFR 614.4945 - Forced placement of flood insurance.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Forced placement of flood insurance. 614.4945... OPERATIONS Flood Insurance Requirements § 614.4945 Forced placement of flood insurance. If a System... not covered by flood insurance or are covered by flood insurance in an amount less than the amount...
NASA Astrophysics Data System (ADS)
Tellman, B.; Sullivan, J.; Kettner, A.; Brakenridge, G. R.; Slayback, D. A.; Kuhn, C.; Doyle, C.
2016-12-01
There is an increasing need to understand flood vulnerability as the societal and economic effects of flooding increases. Risk models from insurance companies and flood models from hydrologists must be calibrated based on flood observations in order to make future predictions that can improve planning and help societies reduce future disasters. Specifically, to improve these models both traditional methods of flood prediction from physically based models as well as data-driven techniques, such as machine learning, require spatial flood observation to validate model outputs and quantify uncertainty. A key dataset that is missing for flood model validation is a global historical geo-database of flood event extents. Currently, the most advanced database of historical flood extent is hosted and maintained at the Dartmouth Flood Observatory (DFO) that has catalogued 4320 floods (1985-2015) but has only mapped 5% of these floods. We are addressing this data gap by mapping the inventory of floods in the DFO database to create a first-of- its-kind, comprehensive, global and historical geospatial database of flood events. To do so, we combine water detection algorithms on MODIS and Landsat 5,7 and 8 imagery in Google Earth Engine to map discrete flood events. The created database will be available in the Earth Engine Catalogue for download by country, region, or time period. This dataset can be leveraged for new data-driven hydrologic modeling using machine learning algorithms in Earth Engine's highly parallelized computing environment, and we will show examples for New York and Senegal.
Flood mapping from Sentinel-1 and Landsat-8 data: a case study from river Evros, Greece
NASA Astrophysics Data System (ADS)
Kyriou, Aggeliki; Nikolakopoulos, Konstantinos
2015-10-01
Floods are suddenly and temporary natural events, affecting areas which are not normally covered by water. The influence of floods plays a significant role both in society and the natural environment, therefore flood mapping is crucial. Remote sensing data can be used to develop flood map in an efficient and effective way. This work is focused on expansion of water bodies overtopping natural levees of the river Evros, invading the surroundings areas and converting them in flooded. Different techniques of flood mapping were used using data from active and passive remote sensing sensors like Sentinlel-1 and Landsat-8 respectively. Space borne pairs obtained from Sentinel-1 were processed in this study. Each pair included an image during the flood, which is called "crisis image" and another one before the event, which is called "archived image". Both images covering the same area were processed producing a map, which shows the spread of the flood. Multispectral data From Landsat-8 were also processed in order to detect and map the flooded areas. Different image processing techniques were applied and the results were compared to the respective results of the radar data processing.
Yin, Xiaojian; Sakata, Katsumi; Nanjo, Yohei; Komatsu, Setsuko
2014-06-25
Flooding has a severe negative effect on soybean cultivation in the early stages of growth. To obtain a better understanding of the response mechanisms of soybean to flooding stress, initial changes in root tip proteins under flooding were analyzed using two proteomic techniques. Two-day-old soybeans were treated with flooding for 3, 6, 12, and 24h. The weight of soybeans increased during the first 3h of flooding, but root elongation was not observed. Using gel-based and gel-free proteomic techniques, 115 proteins were identified in root tips, of which 9 proteins were commonly detected by both methods. The 71 proteins identified by the gel-free proteomics were analyzed by a hierarchical clustering method based on induction levels during the flooding, and the proteins were divided into 5 clusters. Additional interaction analysis of the proteins revealed that ten proteins belonging to cluster I formed the center of a protein interaction network. mRNA expression analysis of these ten proteins showed that citrate lyase and heat shock protein 70 were down-regulated, whereas calreticulin was up-regulated in initial phase of flooding. These results suggest that flooding stress to soybean induces calcium-related signal transduction, which might play important roles in the early responses to flooding. Flooding has a severe negative effect on soybean cultivation, particularly in the early stages of growth. To better understand the response mechanisms of soybean to the early stages of flooding stress, two proteomic techniques were used. Two-day-old soybeans were treated without or with flooding for 3, 6, 12, and 24h. The fresh weight of soybeans increased during the first 3h of flooding stress, but the growth then slowed and no root elongation was observed. Using gel-based and gel-free proteomic techniques, 115 proteins were identified in root tips, of which 9 proteins were commonly detected by both methods. The 71 proteins identified by the gel-free proteomics were analyzed by a hierarchical clustering method based on induction levels during the flooding stress, and 5 protein clusters were recognized. Protein interaction analysis revealed that ten proteins belonging to cluster I formed the center of a protein interaction network. mRNA expression analysis of these ten proteins showed that citrate lyase and heat shock protein 70 were down-regulated in response to flooding stress, whereas calreticulin was up-regulated. These results suggest that flooding stress to soybean induces calcium-related signal transduction, which might play important roles in the early responses to flooding. Copyright © 2014 Elsevier B.V. All rights reserved.
Analysis of flood inundation in ungauged basins based on multi-source remote sensing data.
Gao, Wei; Shen, Qiu; Zhou, Yuehua; Li, Xin
2018-02-09
Floods are among the most expensive natural hazards experienced in many places of the world and can result in heavy losses of life and economic damages. The objective of this study is to analyze flood inundation in ungauged basins by performing near-real-time detection with flood extent and depth based on multi-source remote sensing data. Via spatial distribution analysis of flood extent and depth in a time series, the inundation condition and the characteristics of flood disaster can be reflected. The results show that the multi-source remote sensing data can make up the lack of hydrological data in ungauged basins, which is helpful to reconstruct hydrological sequence; the combination of MODIS (moderate-resolution imaging spectroradiometer) surface reflectance productions and the DFO (Dartmouth Flood Observatory) flood database can achieve the macro-dynamic monitoring of the flood inundation in ungauged basins, and then the differential technique of high-resolution optical and microwave images before and after floods can be used to calculate flood extent to reflect spatial changes of inundation; the monitoring algorithm for the flood depth combining RS and GIS is simple and easy and can quickly calculate the depth with a known flood extent that is obtained from remote sensing images in ungauged basins. Relevant results can provide effective help for the disaster relief work performed by government departments.
Effects of Flood Control Strategies on Flood Resilience Under Sociohydrological Disturbances
NASA Astrophysics Data System (ADS)
Sung, Kyungmin; Jeong, Hanseok; Sangwan, Nikhil; Yu, David J.
2018-04-01
A community capacity to cope with flood hazards, or community flood resilience, emerges from the interplay of hydrological and social processes. This interplay can be significantly influenced by the flood control strategy adopted by a society, i.e., how a society sets its desired flood protection level and strives to achieve this goal. And this interplay can be further complicated by rising land-sea level differences, seasonal water level fluctuations, and economic change. But not much research has been done on how various forms of flood control strategies affect human-flood interactions under these disturbances and therefore flood resilience in the long run. The current study is an effort to address these issues by developing a conceptual model of human-flood interaction mediated by flood control strategies. Our model extends the existing model of Yu et al. (2017), who investigated the flood resilience of a community-based flood protection system in coastal Bangladesh. The major extensions made in this study are inclusions of various forms of flood control strategies (both adaptive and nonadaptive ones), the challenge of rising land-sea level differences, and various high tide level scenarios generated from modifying the statistical variances and averages. Our results show that adaptive forms of flood control strategies tend to outperform nonadaptive ones for maintaining the model community's flood protection system. Adaptive strategies that dynamically adjust target flood protection levels through close monitoring of flood damages and social memories of flood risk can help the model community deal with various disturbances.
Somerset County Flood Information System
Hoppe, Heidi L.
2007-01-01
The timely warning of a flood is crucial to the protection of lives and property. One has only to recall the floods of August 2, 1973, September 16 and 17, 1999, and April 16, 2007, in Somerset County, New Jersey, in which lives were lost and major property damage occurred, to realize how costly, especially in terms of human life, an unexpected flood can be. Accurate forecasts and warnings cannot be made, however, without detailed information about precipitation and streamflow in the drainage basin. Since the mid 1960's, the National Weather Service (NWS) has been able to forecast flooding on larger streams in Somerset County, such as the Raritan and Millstone Rivers. Flooding on smaller streams in urban areas was more difficult to predict. In response to this problem the NWS, in cooperation with the Green Brook Flood Control Commission, installed a precipitation gage in North Plainfield, and two flash-flood alarms, one on Green Brook at Seeley Mills and one on Stony Brook at Watchung, in the early 1970's. In 1978, New Jersey's first countywide flood-warning system was installed by the U.S. Geological Survey (USGS) in Somerset County. This system consisted of a network of eight stage and discharge gages equipped with precipitation gages linked by telephone telemetry and eight auxiliary precipitation gages. The gages were installed throughout the county to collect precipitation and runoff data that could be used to improve flood-monitoring capabilities and flood-frequency estimates. Recognizing the need for more detailed hydrologic information for Somerset County, the USGS, in cooperation with Somerset County, designed and installed the Somerset County Flood Information System (SCFIS) in 1990. This system is part of a statewide network of stream gages, precipitation gages, weather stations, and tide gages that collect data in real time. The data provided by the SCFIS improve the flood forecasting ability of the NWS and aid Somerset County and municipal agencies in the planning and execution of flood-preparation and emergency-evacuation procedures in the county. This fact sheet describes the SCFIS and identifies its benefits.
The role of interactions along the flood process chain and implications for risk assessment
NASA Astrophysics Data System (ADS)
Vorogushyn, Sergiy; Apel, Heiko; Viet Nguyen, Dung; Guse, Björn; Kreibich, Heidi; Lüdtke, Stefan; Schröter, Kai; Merz, Bruno
2017-04-01
Floods with their manifold characteristics are shaped by various processes along the flood process chain - from triggering meteorological extremes through catchment and river network process down to impacts on societies. In flood risk systems numerous interactions and feedbacks along the process chain may occur which finally shape spatio-temporal flood patterns and determine the ultimate risk. In this talk, we review some important interactions in the atmosphere-catchment, river-dike-floodplain and vulnerability compartments of the flood risk system. We highlight the importance of spatial interactions for flood hazard and risk assessment. For instance, the role of spatial rainfall structure or wave superposition in river networks is elucidated with selected case studies. In conclusion, we show the limits of current methods in assessment of large-scale flooding and outline the approach to more comprehensive risk assessment based on our regional flood risk model (RFM) for Germany.
The Financial Benefit of Early Flood Warnings in Europe
NASA Astrophysics Data System (ADS)
Pappenberger, Florian; Cloke, Hannah L.; Wetterhall, Fredrik; Parker, Dennis J.; Richardson, David; Thielen, Jutta
2015-04-01
Effective disaster risk management relies on science based solutions to close the gap between prevention and preparedness measures. The outcome of consultations on the UNIDSR post-2015 framework for disaster risk reduction highlight the need for cross-border early warning systems to strengthen the preparedness phases of disaster risk management in order to save people's lives and property and reduce the overall impact of severe events. In particular, continental and global scale flood forecasting systems provide vital information to various decision makers with which early warnings of floods can be made. Here the potential monetary benefits of early flood warnings using the example of the European Flood Awareness System (EFAS) are calculated based on pan-European Flood damage data and calculations of potential flood damage reductions. The benefits are of the order of 400 Euro for every 1 Euro invested. Because of the uncertainties which accompany the calculation, a large sensitivity analysis is performed in order to develop an envelope of possible financial benefits. Current EFAS system skill is compared against perfect forecasts to demonstrate the importance of further improving the skill of the forecasts. Improving the response to warnings is also essential in reaping the benefits of flood early warnings.
Testing an innovative framework for flood forecasting, monitoring and mapping in Europe
NASA Astrophysics Data System (ADS)
Dottori, Francesco; Kalas, Milan; Lorini, Valerio; Wania, Annett; Pappenberger, Florian; Salamon, Peter; Ramos, Maria Helena; Cloke, Hannah; Castillo, Carlos
2017-04-01
Between May and June 2016, France was hit by severe floods, particularly in the Loire and Seine river basins. In this work, we use this case study to test an innovative framework for flood forecasting, mapping and monitoring. More in detail, the system integrates in real-time two components of the Copernicus Emergency mapping services, namely the European Flood Awareness System and the satellite-based Rapid Mapping, with new procedures for rapid risk assessment and social media and news monitoring. We explore in detail the performance of each component of the system, demonstrating the improvements in respect to stand-alone flood forecasting and monitoring systems. We show how the performances of the forecasting component can be refined using the real-time feedback from social media monitoring to identify which areas were flooded, to evaluate the flood intensity, and therefore to correct impact estimations. Moreover, we show how the integration with impact forecast and social media monitoring can improve the timeliness and efficiency of satellite based emergency mapping, and reduce the chances of missing areas where flooding is already happening. These results illustrate how the new integrated approach leads to a better and earlier decision making and a timely evaluation of impacts.
Watson, Kara M.; Niemoczynski, Michal J.
2014-01-01
Digital flood-inundation maps for a 5.4-mile reach of the Saddle River in New Jersey from Hollywood Avenue in Ho-Ho-Kus Borough downstream through the Village of Ridgewood and Paramus Borough to the confluence with Hohokus Brook in the Village of Ridgewood were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Saddle River at Ridgewood, New Jersey (station 01390500). Current conditions for estimating near real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/nwis/uv?site_no=01390500 or at the National Weather Services (NWS) Advanced Hydrologic Prediction Service (AHPS) at http://water.weather.gov/ahps2/hydrograph.php?wfo=okx&gage=rwdn4. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation (March 11, 2011) at the USGS streamgage 01390500, Saddle River at Ridgewood, New Jersey. The hydraulic model was then used to compute 10 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum, North American Vertical Datum of 1988 (NAVD 88), and ranging from 5 ft, the NWS “action and minor flood stage”, to 14 ft, which is the maximum extent of the stage-discharge rating and 0.6 ft higher than the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system 3-meter (9.84-ft) digital elevation model derived from Light Detection and Ranging (lidar) data in order to delineate the area flooded at each water level. The availability of these maps along with information on the Internet regarding current stage from the USGS streamgage provides emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures as well as for post-flood recovery efforts.
Circulation in a bay influenced by flooding of a river discharging outside the bay
NASA Astrophysics Data System (ADS)
Kakehi, Shigeho; Takagi, Takamasa; Okabe, Katsuaki; Takayanagi, Kazufumi
2017-03-01
To investigate the influence of a river discharging outside a bay on circulation in the bay, we carried out current and salinity measurements from mooring systems and hydrographic observations in Matsushima Bay, Japan, and off the Naruse River, which discharges outside the bay. Previously, enhancement of horizontal circulation in the bay induced by increased freshwater input from the Naruse River was reported to have degraded the seedling yield of wild Pacific oysters in the bay, but the freshwater inflow from the river was not directly measured. Our hydrographic observations in Katsugigaura Strait, approximately 3 km southwest of the Naruse River mouth, detected freshwater derived from the river. The mooring data revealed that freshwater discharged by the river flowed into Matsushima Bay via the strait and that the freshwater transport increased when the river was in flood. The inflow through straits other than Katsugigaura was estimated by a box model analysis to be 26-145 m3 s-1 under normal river discharge conditions, and it decreased to 6 m3 s-1 during flood conditions. During flood events, the salt and water budgets in the bay were maintained by the horizontal circulation: inflow occurred mainly via Katsugigaura Strait, and outflow was mainly via other straits.
NASA Astrophysics Data System (ADS)
Xuejiao, M.; Chang, J.; Wang, Y.
2017-12-01
Flood risk reduction with non-engineering measures has become the main idea for flood management. It is more effective for flood risk management to take various non-engineering measures. In this paper, a flood control operation model for cascade reservoirs in the Upper Yellow River was proposed to lower the flood risk of the water system with multi-reservoir by combining the reservoir flood control operation (RFCO) and flood early warning together. Specifically, a discharge control chart was employed to build the joint RFCO simulation model for cascade reservoirs in the Upper Yellow River. And entropy-weighted fuzzy comprehensive evaluation method was adopted to establish a multi-factorial risk assessment model for flood warning grade. Furthermore, after determining the implementing mode of countermeasures with future inflow, an intelligent optimization algorithm was used to solve the optimization model for applicable water release scheme. In addition, another model without any countermeasure was set to be a comparative experiment. The results show that the model developed in this paper can further decrease the flood risk of water system with cascade reservoirs. It provides a new approach to flood risk management by coupling flood control operation and flood early warning of cascade reservoirs.
Predicting Flood Hazards in Systems with Multiple Flooding Mechanisms
NASA Astrophysics Data System (ADS)
Luke, A.; Schubert, J.; Cheng, L.; AghaKouchak, A.; Sanders, B. F.
2014-12-01
Delineating flood zones in systems that are susceptible to flooding from a single mechanism (riverine flooding) is a relatively well defined procedure with specific guidance from agencies such as FEMA and USACE. However, there is little guidance in delineating flood zones in systems that are susceptible to flooding from multiple mechanisms such as storm surge, waves, tidal influence, and riverine flooding. In this study, a new flood mapping method which accounts for multiple extremes occurring simultaneously is developed and exemplified. The study site in which the method is employed is the Tijuana River Estuary (TRE) located in Southern California adjacent to the U.S./Mexico border. TRE is an intertidal coastal estuary that receives freshwater flows from the Tijuana River. Extreme discharge from the Tijuana River is the primary driver of flooding within TRE, however tide level and storm surge also play a significant role in flooding extent and depth. A comparison between measured flows at the Tijuana River and ocean levels revealed a correlation between extreme discharge and ocean height. Using a novel statistical method based upon extreme value theory, ocean heights were predicted conditioned up extreme discharge occurring within the Tijuana River. This statistical technique could also be applied to other systems in which different factors are identified as the primary drivers of flooding, such as significant wave height conditioned upon tide level, for example. Using the predicted ocean levels conditioned upon varying return levels of discharge as forcing parameters for the 2D hydraulic model BreZo, the 100, 50, 20, and 10 year floodplains were delineated. The results will then be compared to floodplains delineated using the standard methods recommended by FEMA for riverine zones with a downstream ocean boundary.
NASA Astrophysics Data System (ADS)
Izumida, Atsuto; Uchiyama, Shoichiro; Sugai, Toshihiko
2017-09-01
Geomorphic impacts of a disastrous crevasse splay that formed in September 2015 and its post-formation modifications were quantitatively documented by using repeated, high-definition digital surface models (DSMs) of an inhabited and cultivated floodplain of the Kinu River, central Japan. The DSMs were based on pre-flood (resolution: 2 m) and post-flood (resolution: 1 m) aerial light detection and ranging (lidar) data from January 2007 and September 2015, respectively, and on structure-from-motion (SfM) photogrammetry data (resolution: 3.84 cm) derived from aerial photos taken by an unmanned aerial vehicle (UAV) in December 2015. After elimination of systematic errors among the DSMs and down-sampling of the SfM-derived DSM, elevation changes on the order of 10-1 m - including not only topography but also growth of vegetation, vanishing of flood waters, and restoration and repair works - were detected. Comparison of the DSMs showed that the volume eroded by the flood was more than twice the deposited volume in the area within 300-500 m of the breached artificial levee, where the topography was significantly affected. The results suggest that DSMs based on a combination of UAV-SfM and lidar data can be used to quantify, rapidly and in rich detail, topographic changes on floodplains caused by floods.
NASA Astrophysics Data System (ADS)
Dittes, Beatrice; Špačková, Olga; Ebrahimian, Negin; Kaiser, Maria; Rieger, Wolfgang; Disse, Markus; Straub, Daniel
2017-04-01
Flood risk estimates are subject to significant uncertainties, e.g. due to limited records of historic flood events, uncertainty in flood modeling, uncertain impact of climate change or uncertainty in the exposure and loss estimates. In traditional design of flood protection systems, these uncertainties are typically just accounted for implicitly, based on engineering judgment. In the AdaptRisk project, we develop a fully quantitative framework for planning of flood protection systems under current and future uncertainties using quantitative pre-posterior Bayesian decision analysis. In this contribution, we focus on the quantification of the uncertainties and study their relative influence on the flood risk estimate and on the planning of flood protection systems. The following uncertainty components are included using a Bayesian approach: 1) inherent and statistical (i.e. limited record length) uncertainty; 2) climate uncertainty that can be learned from an ensemble of GCM-RCM models; 3) estimates of climate uncertainty components not covered in 2), such as bias correction, incomplete ensemble, local specifics not captured by the GCM-RCM models; 4) uncertainty in the inundation modelling; 5) uncertainty in damage estimation. We also investigate how these uncertainties are possibly reduced in the future when new evidence - such as new climate models, observed extreme events, and socio-economic data - becomes available. Finally, we look into how this new evidence influences the risk assessment and effectivity of flood protection systems. We demonstrate our methodology for a pre-alpine catchment in southern Germany: the Mangfall catchment in Bavaria that includes the city of Rosenheim, which suffered significant losses during the 2013 flood event.
From Environmental Risks, As Problems, To Earth Observations As Solutions To Those Problems
NASA Astrophysics Data System (ADS)
Rycroft, M. J.
This paper introduces the topic of space techniquesfor environmental risks. It does this by giving someexamples of the damage and havoc wrought in recent tragic events -mudslides, floods, cyclones, earthquakes and theChernobyl disaster. It introduces the concept ofa Geographic Information System where informationderived from remote sensing observations made fromspace is combined with other types of informationand processed in a computer.Seven examples are then considered in more detail -the early 1995 flood in The Netherlands and otherhydrological issues, land use studies for agriculture,the Vegetation Index and land degradation ordesertification, hurricane Fran over South andNorth Carolina in September 1996, change detection,ocean catastrophes and atmospheric disasters. Theyillustrate some ways in which information derivedfrom space observations can be used to benefitthe Earth's population.
NASA Astrophysics Data System (ADS)
Liu, Y.; Zhou, J.; Song, L.; Zou, Q.; Guo, J.; Wang, Y.
2014-02-01
In recent years, an important development in flood management has been the focal shift from flood protection towards flood risk management. This change greatly promoted the progress of flood control research in a multidisciplinary way. Moreover, given the growing complexity and uncertainty in many decision situations of flood risk management, traditional methods, e.g., tight-coupling integration of one or more quantitative models, are not enough to provide decision support for managers. Within this context, this paper presents a beneficial methodological framework to enhance the effectiveness of decision support systems, through the dynamic adaptation of support regarding the needs of the decision-maker. In addition, we illustrate a loose-coupling technical prototype for integrating heterogeneous elements, such as multi-source data, multidisciplinary models, GIS tools and existing systems. The main innovation is the application of model-driven concepts, which put the system in a state of continuous iterative optimization. We define the new system as a model-driven decision support system (MDSS ). Two characteristics that differentiate the MDSS are as follows: (1) it is made accessible to non-technical specialists; and (2) it has a higher level of adaptability and compatibility. Furthermore, the MDSS was employed to manage the flood risk in the Jingjiang flood diversion area, located in central China near the Yangtze River. Compared with traditional solutions, we believe that this model-driven method is efficient, adaptable and flexible, and thus has bright prospects of application for comprehensive flood risk management.
NASA Astrophysics Data System (ADS)
Llasat, Maria Carmen; Marcos, Raul; Turco, Marco; Gilabert, Joan; Llasat-Botija, Montserrat
2016-10-01
The aim of this paper is to analyse the potential relationship between flash flood events and convective precipitation in Catalonia, as well as any related trends. The paper starts with an overview of flash floods and their trends in the Mediterranean region, along with their associated factors, followed by the definition of, identification of, and trends in convective precipitation. After this introduction the paper focuses on the north-eastern Iberian Peninsula, for which there is a long-term precipitation series (since 1928) of 1-min precipitation from the Fabra Observatory, as well as a shorter (1996-2011) but more extensive precipitation series (43 rain gauges) of 5-min precipitation. Both series have been used to characterise the degree of convective contribution to rainfall, introducing the β parameter as the ratio between convective precipitation versus total precipitation in any period. Information about flood events was obtained from the INUNGAMA database (a flood database created by the GAMA team), with the aim of finding any potential links to convective precipitation. These flood data were gathered using information on damage where flood is treated as a multifactorial risk, and where any trend or anomaly might have been caused by one or more factors affecting hazard, vulnerability or exposure. Trend analysis has shown an increase in flash flood events. The fact that no trends were detected in terms of extreme values of precipitation on a daily scale, nor on the associated ETCCDI (Expert Team on Climate Change Detection and Indices) extreme index, could point to an increase in vulnerability, an increase in exposure, or changes in land use. However, the summer increase in convective precipitation was concentrated in less torrential events, which could partially explain this positive trend in flash flood events. The β parameter has been also used to characterise the type of flood event according to the features of the precipitation. The highest values correspond to short and local events, usually with daily β values above 0.5, while the minimum threshold of daily β for catastrophic flash floods is 0.31.
Probabilistic mapping of flood-induced backscatter changes in SAR time series
NASA Astrophysics Data System (ADS)
Schlaffer, Stefan; Chini, Marco; Giustarini, Laura; Matgen, Patrick
2017-04-01
The information content of flood extent maps can be increased considerably by including information on the uncertainty of the flood area delineation. This additional information can be of benefit in flood forecasting and monitoring. Furthermore, flood probability maps can be converted to binary maps showing flooded and non-flooded areas by applying a threshold probability value pF = 0.5. In this study, a probabilistic change detection approach for flood mapping based on synthetic aperture radar (SAR) time series is proposed. For this purpose, conditional probability density functions (PDFs) for land and open water surfaces were estimated from ENVISAT ASAR Wide Swath (WS) time series containing >600 images using a reference mask of permanent water bodies. A pixel-wise harmonic model was used to account for seasonality in backscatter from land areas caused by soil moisture and vegetation dynamics. The approach was evaluated for a large-scale flood event along the River Severn, United Kingdom. The retrieved flood probability maps were compared to a reference flood mask derived from high-resolution aerial imagery by means of reliability diagrams. The obtained performance measures indicate both high reliability and confidence although there was a slight under-estimation of the flood extent, which may in part be attributed to topographically induced radar shadows along the edges of the floodplain. Furthermore, the results highlight the importance of local incidence angle for the separability between flooded and non-flooded areas as specular reflection properties of open water surfaces increase with a more oblique viewing geometry.
NASA Global Flood Mapping System
NASA Technical Reports Server (NTRS)
Policelli, Fritz; Slayback, Dan; Brakenridge, Bob; Nigro, Joe; Hubbard, Alfred
2017-01-01
Product utility key factors: Near real time, automated production; Flood spatial extent Cloudiness Pixel resolution: 250m; Flood temporal extent; Flash floods short duration on ground?; Landcover--Water under vegetation cover vs open water
Box, Stephen E.; Bookstrom, Arthur A.; Ikramuddin, Mohammed
2005-01-01
Environmental problems associated with the dispersion of metal-enriched sediment into the Coeur d'Alene-Spokane River system downstream from the Coeur d'Alene Mining District in northern Idaho have been a cause of litigation since 1903, 18 years after the initiation of mining for lead, zinc, and silver. Although direct dumping of waste materials into the river by active mining operations stopped in 1968, metal-enriched sediment continues to be mobilized during times of high runoff and deposited on valley flood plains and in Coeur d'Alene Lake (Horowitz and others, 1993). To gauge the geographic and temporal variations in the metal contents of flood sediment and to provide constraints on the sources and processes responsible for those variations, we collected samples of suspended sediment and overbank deposits during and after four high-flow events in 1995, 1996, and 1997 in the Coeur d'Alene-Spokane River system with estimated recurrence intervals ranging from 2 to 100 years. Suspended sediment enriched in lead, zinc, silver, antimony, arsenic, cadmium, and copper was detected over a distance of more than 130 mi (the downstream extent of sampling) downstream of the mining district. Strong correlations of all these elements in suspended sediment with each other and with iron and manganese are apparent when samples are grouped by reach (tributaries to the South Fork of the Coeur d'Alene River, the South Fork of the Coeur d'Alene River, the main stem of the Coeur d'Alene River, and the Spokane River). Elemental correlations with iron and manganese, along with observations by scanning electron microscopy, indicate that most of the trace metals are associated with Fe and Mn oxyhydroxide compounds. Changes in elemental correlations by reach suggest that the sources of metal-enriched sediment change along the length of the drainage. Metal contents of suspended sediment generally increase through the mining district along the South Fork of the Coeur d'Alene River, decrease below the confluence of the North and South Forks, and then increase again downstream of the gradient flattening below Cataldo. Metal contents of suspended sediment in the Spokane River below Coeur d'Alene Lake were comparable to those of suspended sediment in the main stem of the Coeur d'Alene River above the lake during the 1997 spring runoff, but with somewhat higher Zn contents. Daily suspended-sediment loads were about 100 times larger in the 1996 flood (50-100-year recurrence interval) than in the smaller 1997 floods (2-5-year recurrence intervals). Significant differences in metal ratios and contents are also apparent between the two flood types. The predominant source of suspended sediment in the larger 1996 flood was previously deposited, metal-enriched flood-plain sediment, identified by its Zn/Pb ratio less than 1. Suspended sediment in the smaller 1997 floods had metal ratios distinct from those of the flood-plain deposits and was primarily derived from metal-enriched sediment stored within the stream channel, identified by a Zn/Pb ratio greater than 1. Sediment deposited during overbank flooding on the immediate streambank or natural levee of the river typically consists of sandy material with metal ratios and contents similar to those of the sandy streambed sediment in the adjacent river reach. Samples of overbank deposits in backlevee marshes collected after the 1996 flood have metal ratios similar to those of peak-flow suspended sediment in the same river reach, but generally lower metal contents.
NASA Astrophysics Data System (ADS)
Bao, Hongjun; Zhao, Linna
2012-02-01
A coupled atmospheric-hydrologic-hydraulic ensemble flood forecasting model, driven by The Observing System Research and Predictability Experiment (THORPEX) Interactive Grand Global Ensemble (TIGGE) data, has been developed for flood forecasting over the Huaihe River. The incorporation of numerical weather prediction (NWP) information into flood forecasting systems may increase forecast lead time from a few hours to a few days. A single NWP model forecast from a single forecast center, however, is insufficient as it involves considerable non-predictable uncertainties and leads to a high number of false alarms. The availability of global ensemble NWP systems through TIGGE offers a new opportunity for flood forecast. The Xinanjiang model used for hydrological rainfall-runoff modeling and the one-dimensional unsteady flow model applied to channel flood routing are coupled with ensemble weather predictions based on the TIGGE data from the Canadian Meteorological Centre (CMC), the European Centre for Medium-Range Weather Forecasts (ECMWF), the UK Met Office (UKMO), and the US National Centers for Environmental Prediction (NCEP). The developed ensemble flood forecasting model is applied to flood forecasting of the 2007 flood season as a test case. The test case is chosen over the upper reaches of the Huaihe River above Lutaizi station with flood diversion and retarding areas. The input flood discharge hydrograph from the main channel to the flood diversion area is estimated with the fixed split ratio of the main channel discharge. The flood flow inside the flood retarding area is calculated as a reservoir with the water balance method. The Muskingum method is used for flood routing in the flood diversion area. A probabilistic discharge and flood inundation forecast is provided as the end product to study the potential benefits of using the TIGGE ensemble forecasts. The results demonstrate satisfactory flood forecasting with clear signals of probability of floods up to a few days in advance, and show that TIGGE ensemble forecast data are a promising tool for forecasting of flood inundation, comparable with that driven by raingauge observations.
Processing and utilization of LiDAR data as a support for a good management of DDBR
NASA Astrophysics Data System (ADS)
Nichersu, I.; Grigoras, I.; Constantinescu, A.; Mierla, M.; Tifanov, C.
2012-04-01
Danube Delta Biosphere Reserve (DDBR) has 5,800 km2 as surface and it is situated in the South-East of Europe, in the East of Romania. The paper is taking into account the data related to the elevation surfaces of the DDBR (Digital Terrain Model DTM and Digital Surface Model DSM). To produce such kind of models of elevation for the entire area of DDBR it was used the most modern method that utilizes the Light Detection And Ranging (LiDAR). The raw LiDAR data (x, y, z) for each point were transformed into grid formats for DTM and DSM. Based on these data multiple GIS analyses can be done for management purposes : hydraulic modeling 1D2D scenarios, flooding regime and protection, biomass volume estimation, GIS biodiversity processing. These analyses are very useful in the management planning process. The hydraulic modeling 1D2D scenarios are used by the administrative authority to predict the sense of the fluvial water flow and also to predict the places where the flooding could occur. Also it can be predicted the surface of the terrain that will be occupied by the water from floods. Flooding regime gives information about the frequency of the floods and also the intensity of these. In the same time it could be predicted the time of water remanence period. The protection face of the flooding regime is in direct relation with the socio-cultural communities and all their annexes those that are in risk of being flooded. This raises the problem of building dykes and other flooding protection systems. The biomass volume contains information derived from the LiDAR cloud points that describes only the vegetation. The volume of biomass is an important item in the management of a Biosphere Reserve. Also the LiDAR cloud points that refer to vegetation could help in identifying the groups of vegetal association. All these information corroborated with other information build good premises for a good management. Keywords: Danube Delta Biosphere Reserve, LiDAR data, DTM, DSM, flooding, management
Flood Hazards - A National Threat
,
2006-01-01
In the late summer of 2005, the remarkable flooding brought by Hurricane Katrina, which caused more than $200 billion in losses, constituted the costliest natural disaster in U.S. history. However, even in typical years, flooding causes billions of dollars in damage and threatens lives and property in every State. Natural processes, such as hurricanes, weather systems, and snowmelt, can cause floods. Failure of levees and dams and inadequate drainage in urban areas can also result in flooding. On average, floods kill about 140 people each year and cause $6 billion in property damage. Although loss of life to floods during the past half-century has declined, mostly because of improved warning systems, economic losses have continued to rise due to increased urbanization and coastal development.
Kick, Edward L; Fraser, James C; Fulkerson, Gregory M; McKinney, Laura A; De Vries, Daniel H
2011-07-01
Of all natural disasters, flooding causes the greatest amount of economic and social damage. The United States' Federal Emergency Management Agency (FEMA) uses a number of hazard mitigation grant programmes for flood victims, including mitigation offers to relocate permanently repetitive flood loss victims. This study examines factors that help to explain the degree of difficulty repetitive flood loss victims experience when they make decisions about relocating permanently after multiple flood losses. Data are drawn from interviews with FEMA officials and a survey of flood victims from eight repetitive flooding sites. The qualitative and quantitative results show the importance of rational choices by flood victims in their mitigation decisions, as they relate to financial variables, perceptions of future risk, attachments to home and community, and the relationships between repetitive flood loss victims and the local flood management officials who help them. The results offer evidence to suggest the value of a more community-system approach to FEMA relocation practices. © 2011 The Author(s). Disasters © Overseas Development Institute, 2011.
NASA Astrophysics Data System (ADS)
Moon, Y. I.; Kim, M. S.; Choi, J. H.; Yuk, G. M.
2017-12-01
eavy rainfall has become a recent major cause of urban area flooding due to the climate change and urbanization. To prevent property damage along with casualties, a system which can alert and forecast urban flooding must be developed. Optimal performance of reducing flood damage can be expected of urban drainage facilities when operated in smaller rainfall events over extreme ones. Thus, the purpose of this study is to execute: A) flood forecasting system using runoff analysis based on short term rainfall; and B) flood warning system which operates based on the data from pump stations and rainwater storage in urban basins. In result of the analysis, it is shown that urban drainage facilities using short term rainfall forecasting data by radar will be more effective to reduce urban flood damage than using only the inflow data of the facility. Keywords: Heavy Rainfall, Urban Flood, Short-term Rainfall Forecasting, Optimal operating of urban drainage facilities. AcknowledgmentsThis research was supported by a grant (17AWMP-B066744-05) from Advanced Water Management Research Program (AWMP) funded by Ministry of Land, Infrastructure and Transport of Korean government.
A new modelling framework and mitigation measures for increased resilience to flooding
NASA Astrophysics Data System (ADS)
Valyrakis, Manousos; Alexakis, Athanasios; Solley, Mark
2015-04-01
Flooding in rivers and estuaries is amongst the most significant challenges our society has yet to tackle effectively. Use of floodwall systems is one of the potential measures that can be used to mitigate the detrimental socio-economical and ecological impacts and alleviate the associated costs of flooding. This work demonstrates the utility of such systems for a case study via appropriate numerical simulations, in addition to conducting scaled flume experiments towards obtaining a better understanding of the performance and efficiency of the flood-wall systems. At first, the results of several characteristic inundation modeling scenarios and flood mitigation options, for a flood-prone region in Scotland. In particular, the history and hydrology of the area are discussed and the assumptions and hydraulic model input (model geometry including instream hydraulic structures -such as bridges and weirs- river and floodplain roughness, initial and boundary conditions) are presented, followed by the model results. Emphasis is given on the potential improvements brought about by mitigating flood risk using flood-wall systems. Further, the implementation of the floodwall in mitigating flood risk is demonstrated via appropriate numerical modeling, utilizing HEC-RAS to simulate the effect of a river's rising stage during a flood event, for a specific area. The later part of this work involves the design, building and utilization of a scaled physical model of a flood-wall system. These experiments are carried out at one of the research flumes in the Water Engineering laboratory of the University of Glasgow. These involve an experimental investigation where the increase of force applied on the floodwall is measured for different degrees of deflection of the water in the stream, under the maximum flow discharge that can be carried through without exceeding the floodwall height (and accounting for the effect of super-elevation). These results can be considered upon the implementation phase of floodwalls, when the floodwalls are placed at any arrangement other than parallel to the flow (e.g. along river bends in meandering channels or at river junctions). Such considerations can lead to site-specific optimal designs of direct flood defenses with the rising floodwall system, both in terms of product performance as well as cost efficiency.
K. Bruce Jones; Curtis E. Edmonds; E. Terrance Slonecker; James D. Wickham; Anne C. Neale; Timothy G. Wade; Kurt H. Riitters; William G. Kepner
2008-01-01
Healthy riparian ecosystems in arid and semi-arid regions exhibit shifting patterns of vegetation in response to periodic flooding. Their conditions also depend upon the amount of grazing and other human uses. Taking advantage of these system properties, we developed and tested an approach that utilizes historical Landsat data to track changes in the patterns...
Evaluation of the wind pumped hydropower storage integrated flood mitigation system
NASA Astrophysics Data System (ADS)
Safi, Aishah; Basrawi, Firdaus
2018-04-01
As Wind Pumped Hydropower Storage (WPHS) need high cost to construct, it is important to study their impacts on economic and environmental aspects. Thus, this research aims to evaluate their economic and environmental performances. First, Hybrid Optimization Model for Electric Renewable (HOMER) was used to simulate power generation system with and without the flood reservoir. Next, the total amount of emitted air pollutant was used to evaluate the environmental impacts. It was found the wind-diesel with reservoir storage system (A-III) will have much lower NPC than other systems that do not include reservoir for flood mitigation when the cost of flood losses are included in the total Net Present Cost (NPC). The NPC for system A-III was RM 1.52 million and for diesel standalone system (A-I) is RM 10.8 million when the cost of flood losses are included in the total NPC. Between both energy systems, the amount of pollutants emitted by the A-III system was only 408 kg-CO2/year which is much less than the A-I system which is 99, 754 kg of carbon dioxide per year. To conclude, the WPHS integrated with flood mitigation system seems promising in the aspects of economic and environment.
Mhuantong, Wuttichai; Wongwilaiwalin, Sarunyou; Laothanachareon, Thanaporn; Eurwilaichitr, Lily; Tangphatsornruang, Sithichoke; Boonchayaanant, Benjaporn; Limpiyakorn, Tawan; Pattaragulwanit, Kobchai; Punmatharith, Thantip; McEvoy, John; Khan, Eakalak; Rachakornkij, Manaskorn; Champreda, Verawat
2015-01-01
The Thailand flood crisis in 2011 was one of the largest recorded floods in modern history, causing enormous damage to the economy and ecological habitats of the country. In this study, bacterial and fungal diversity in sediments and waters collected from ten flood areas in Bangkok and its suburbs, covering residential and agricultural areas, were analyzed using high-throughput 454 pyrosequencing of 16S rRNA gene and internal transcribed spacer sequences. Analysis of microbial community showed differences in taxa distribution in water and sediment with variations in the diversity of saprophytic microbes and sulfate/nitrate reducers among sampling locations, suggesting differences in microbial activity in the habitats. Overall, Proteobacteria represented a major bacterial group in waters, while this group co-existed with Firmicutes, Bacteroidetes, and Actinobacteria in sediments. Anaeromyxobacter, Steroidobacter, and Geobacter were the dominant bacterial genera in sediments, while Sulfuricurvum, Thiovirga, and Hydrogenophaga predominated in waters. For fungi in sediments, Ascomycota, Glomeromycota, and Basidiomycota, particularly in genera Philipsia, Rozella, and Acaulospora, were most frequently detected. Chytridiomycota and Ascomycota were the major fungal phyla, and Rhizophlyctis and Mortierella were the most frequently detected fungal genera in water. Diversity of sulfate-reducing bacteria, related to odor problems, was further investigated using analysis of the dsrB gene which indicated the presence of sulfate-reducing bacteria of families Desulfobacteraceae, Desulfobulbaceae, Syntrobacteraceae, and Desulfoarculaceae in the flood sediments. The work provides an insight into the diversity and function of microbes related to biological processes in flood areas. PMID:26020967
Geohazard assessment through the analysis of historical alluvial events in Southern Italy
NASA Astrophysics Data System (ADS)
Esposito, Eliana; Violante, Crescenzo
2015-04-01
The risk associated with extreme water events such as flash floods, results from a combination of overflows and landslides hazards. A multi-hazard approach have been utilized to analyze the 1773 flood that occurred in conjunction with heavy rainfall, causing major damage in terms of lost lives and economic cost over an area of 200 km2, including both the coastal strip between Salerno and Maiori and the Apennine hinterland, Campania region - Southern Italy. This area has been affected by a total of 40 flood events over the last five centuries, 26 of them occurred between 1900 and 2000. Streamflow events have produced severe impacts on Cava de' Tirreni (SA) and its territory and in particular four catastrophic floods in 1581, 1773, 1899 and 1954, caused a pervasive pattern of destruction. In the study area, rainstorm events typically occur in small and medium-sized fluvial system, characterized by small catchment areas and high-elevation drainage basins, causing the detachment of large amount of volcaniclastic and siliciclastic covers from the carbonate bedrock. The mobilization of these deposits (slope debris) mixed with rising floodwaters along the water paths can produce fast-moving streamflows of large proportion with significant hazardous implications (Violante et al., 2009). In this context the study of 1773 historical flood allows the detection and the definition of those areas where catastrophic events repeatedly took place over the time. Moreover, it improves the understanding of the phenomena themselves, including some key elements in the management of risk mitigation, such as the restoration of the damage suffered by the buildings and/or the environmental effects caused by the floods.
High-fidelity numerical modeling of the Upper Mississippi River under extreme flood condition
NASA Astrophysics Data System (ADS)
Khosronejad, Ali; Le, Trung; DeWall, Petra; Bartelt, Nicole; Woldeamlak, Solomon; Yang, Xiaolei; Sotiropoulos, Fotis
2016-12-01
We present data-driven numerical simulations of extreme flooding in a large-scale river coupling coherent-structure resolving hydrodynamics with bed morphodynamics under live-bed conditions. The study area is a ∼ 3.2 km long and ∼ 300 m wide reach of the Upper Mississippi River, near Minneapolis MN, which contains several natural islands and man-made hydraulic structures. We employ the large-eddy simulation (LES) and bed-morphodynamic modules of the Virtual Flow Simulator (VFS-Rivers) model, a recently developed in-house code, to investigate the flow and bed evolution of the river during a 100-year flood event. The coupling of the two modules is carried out via a fluid-structure interaction approach using a nested domain approach to enhance the resolution of bridge scour predictions. We integrate data from airborne Light Detection and Ranging (LiDAR), sub-aqueous sonar apparatus on-board a boat and in-situ laser scanners to construct a digital elevation model of the river bathymetry and surrounding flood plain, including islands and bridge piers. A field campaign under base-flow condition is also carried out to collect mean flow measurements via Acoustic Doppler Current Profiler (ADCP) to validate the hydrodynamic module of the VFS-Rivers model. Our simulation results for the bed evolution of the river under the 100-year flood reveal complex sediment transport dynamics near the bridge piers consisting of both scour and refilling events due to the continuous passage of sand dunes. We find that the scour depth near the bridge piers can reach to a maximum of ∼ 9 m. The data-driven simulation strategy we present in this work exemplifies a practical simulation-based-engineering-approach to investigate the resilience of infrastructures to extreme flood events in intricate field-scale riverine systems.
Self-accelerated development of salt karst during flash floods along the Dead Sea Coast, Israel
NASA Astrophysics Data System (ADS)
Avni, Yoav; Lensky, Nadav; Dente, Elad; Shviro, Maayan; Arav, Reuma; Gavrieli, Ittai; Yechieli, Yoseph; Abelson, Meir; Lutzky, Hallel; Filin, Sagi; Haviv, Itai; Baer, Gidon
2016-01-01
We document and analyze the rapid development of a real-time karst system within the subsurface salt layers of the Ze'elim Fan, Dead Sea, Israel by a multidisciplinary study that combines interferometric synthetic aperture radar and light detection and ranging measurements, sinkhole mapping, time-lapse camera monitoring, groundwater level measurements and chemical and isotopic analyses of surface runoff and groundwater. The >1 m/yr drop of Dead Sea water level and the subsequent change in the adjacent groundwater system since the 1960s resulted in flushing of the coastal aquifer by fresh groundwater, subsurface salt dissolution, gradual land subsidence and formation of sinkholes. Since 2010 this process accelerated dramatically as flash floods at the Ze'elim Fan were drained by newly formed sinkholes. During and immediately after these flood events the dissolution rates of the subsurface salt layer increased dramatically, the overlying ground surface subsided, a large number of sinkholes developed over short time periods (hours to days), and salt-saturated water resurged downstream. Groundwater flow velocities increased by more than 2 orders of magnitudes compared to previously measured velocities along the Dead Sea. The process is self-accelerating as salt dissolution enhances subsidence and sinkhole formation, which in turn increase the ponding areas of flood water and generate additional draining conduits to the subsurface. The rapid terrain response is predominantly due to the highly soluble salt. It is enhanced by the shallow depth of the salt layer, the low competence of the newly exposed unconsolidated overburden and the moderate topographic gradients of the Ze'elim Fan.
46 CFR 62.35-10 - Flooding safety.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 2 2014-10-01 2014-10-01 false Flooding safety. 62.35-10 Section 62.35-10 Shipping... Requirements for Specific Types of Automated Vital Systems § 62.35-10 Flooding safety. (a) Automatic bilge.... (b) Remote controls for flooding safety equipment must remain functional under flooding conditions to...
46 CFR 62.35-10 - Flooding safety.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 2 2013-10-01 2013-10-01 false Flooding safety. 62.35-10 Section 62.35-10 Shipping... Requirements for Specific Types of Automated Vital Systems § 62.35-10 Flooding safety. (a) Automatic bilge.... (b) Remote controls for flooding safety equipment must remain functional under flooding conditions to...
46 CFR 62.35-10 - Flooding safety.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 2 2012-10-01 2012-10-01 false Flooding safety. 62.35-10 Section 62.35-10 Shipping... Requirements for Specific Types of Automated Vital Systems § 62.35-10 Flooding safety. (a) Automatic bilge.... (b) Remote controls for flooding safety equipment must remain functional under flooding conditions to...
46 CFR 62.35-10 - Flooding safety.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 2 2011-10-01 2011-10-01 false Flooding safety. 62.35-10 Section 62.35-10 Shipping... Requirements for Specific Types of Automated Vital Systems § 62.35-10 Flooding safety. (a) Automatic bilge.... (b) Remote controls for flooding safety equipment must remain functional under flooding conditions to...
46 CFR 62.35-10 - Flooding safety.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Flooding safety. 62.35-10 Section 62.35-10 Shipping... Requirements for Specific Types of Automated Vital Systems § 62.35-10 Flooding safety. (a) Automatic bilge.... (b) Remote controls for flooding safety equipment must remain functional under flooding conditions to...
NASA Astrophysics Data System (ADS)
Zhou, Qianqian; Leng, Guoyong; Huang, Maoyi
2018-01-01
As China becomes increasingly urbanised, flooding has become a regular occurrence in its major cities. Assessing the effects of future climate change on urban flood volumes is crucial to informing better management of such disasters given the severity of the devastating impacts of flooding (e.g. the 2016 flooding events across China). Although recent studies have investigated the impacts of future climate change on urban flooding, the effects of both climate change mitigation and adaptation have rarely been accounted for together in a consistent framework. In this study, we assess the benefits of mitigating climate change by reducing greenhouse gas (GHG) emissions and locally adapting to climate change by modifying drainage systems to reduce urban flooding under various climate change scenarios through a case study conducted in northern China. The urban drainage model - Storm Water Management Model - was used to simulate urban flood volumes using current and two adapted drainage systems (i.e. pipe enlargement and low-impact development, LID), driven by bias-corrected meteorological forcing from five general circulation models in the Coupled Model Intercomparison Project Phase 5 archive. Results indicate that urban flood volume is projected to increase by 52 % over 2020-2040 compared to the volume in 1971-2000 under the business-as-usual scenario (i.e. Representative Concentration Pathway (RCP) 8.5). The magnitudes of urban flood volumes are found to increase nonlinearly with changes in precipitation intensity. On average, the projected flood volume under RCP 2.6 is 13 % less than that under RCP 8.5, demonstrating the benefits of global-scale climate change mitigation efforts in reducing local urban flood volumes. Comparison of reduced flood volumes between climate change mitigation and local adaptation (by improving drainage systems) scenarios suggests that local adaptation is more effective than climate change mitigation in reducing future flood volumes. This has broad implications for the research community relative to drainage system design and modelling in a changing environment. This study highlights the importance of accounting for local adaptation when coping with future urban floods.
Zhou, Qianqian; Leng, Guoyong; Huang, Maoyi
2018-01-15
As China becomes increasingly urbanised, flooding has become a regular occurrence in its major cities. Assessing the effects of future climate change on urban flood volumes is crucial to informing better management of such disasters given the severity of the devastating impacts of flooding (e.g. the 2016 flooding events across China). Although recent studies have investigated the impacts of future climate change on urban flooding, the effects of both climate change mitigation and adaptation have rarely been accounted for together in a consistent framework. In this study, we assess the benefits of mitigating climate change by reducing greenhouse gas (GHG)more » emissions and locally adapting to climate change by modifying drainage systems to reduce urban flooding under various climate change scenarios through a case study conducted in northern China. The urban drainage model – Storm Water Management Model – was used to simulate urban flood volumes using current and two adapted drainage systems (i.e. pipe enlargement and low-impact development, LID), driven by bias-corrected meteorological forcing from five general circulation models in the Coupled Model Intercomparison Project Phase 5 archive. Results indicate that urban flood volume is projected to increase by 52 % over 2020–2040 compared to the volume in 1971–2000 under the business-as-usual scenario (i.e. Representative Concentration Pathway (RCP) 8.5). The magnitudes of urban flood volumes are found to increase nonlinearly with changes in precipitation intensity. On average, the projected flood volume under RCP 2.6 is 13 % less than that under RCP 8.5, demonstrating the benefits of global-scale climate change mitigation efforts in reducing local urban flood volumes. Comparison of reduced flood volumes between climate change mitigation and local adaptation (by improving drainage systems) scenarios suggests that local adaptation is more effective than climate change mitigation in reducing future flood volumes. This has broad implications for the research community relative to drainage system design and modelling in a changing environment. Furthermore, this study highlights the importance of accounting for local adaptation when coping with future urban floods.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Qianqian; Leng, Guoyong; Huang, Maoyi
As China becomes increasingly urbanised, flooding has become a regular occurrence in its major cities. Assessing the effects of future climate change on urban flood volumes is crucial to informing better management of such disasters given the severity of the devastating impacts of flooding (e.g. the 2016 flooding events across China). Although recent studies have investigated the impacts of future climate change on urban flooding, the effects of both climate change mitigation and adaptation have rarely been accounted for together in a consistent framework. In this study, we assess the benefits of mitigating climate change by reducing greenhouse gas (GHG)more » emissions and locally adapting to climate change by modifying drainage systems to reduce urban flooding under various climate change scenarios through a case study conducted in northern China. The urban drainage model – Storm Water Management Model – was used to simulate urban flood volumes using current and two adapted drainage systems (i.e. pipe enlargement and low-impact development, LID), driven by bias-corrected meteorological forcing from five general circulation models in the Coupled Model Intercomparison Project Phase 5 archive. Results indicate that urban flood volume is projected to increase by 52 % over 2020–2040 compared to the volume in 1971–2000 under the business-as-usual scenario (i.e. Representative Concentration Pathway (RCP) 8.5). The magnitudes of urban flood volumes are found to increase nonlinearly with changes in precipitation intensity. On average, the projected flood volume under RCP 2.6 is 13 % less than that under RCP 8.5, demonstrating the benefits of global-scale climate change mitigation efforts in reducing local urban flood volumes. Comparison of reduced flood volumes between climate change mitigation and local adaptation (by improving drainage systems) scenarios suggests that local adaptation is more effective than climate change mitigation in reducing future flood volumes. This has broad implications for the research community relative to drainage system design and modelling in a changing environment. Furthermore, this study highlights the importance of accounting for local adaptation when coping with future urban floods.« less
Development of web-based services for an ensemble flood forecasting and risk assessment system
NASA Astrophysics Data System (ADS)
Yaw Manful, Desmond; He, Yi; Cloke, Hannah; Pappenberger, Florian; Li, Zhijia; Wetterhall, Fredrik; Huang, Yingchun; Hu, Yuzhong
2010-05-01
Flooding is a wide spread and devastating natural disaster worldwide. Floods that took place in the last decade in China were ranked the worst amongst recorded floods worldwide in terms of the number of human fatalities and economic losses (Munich Re-Insurance). Rapid economic development and population expansion into low lying flood plains has worsened the situation. Current conventional flood prediction systems in China are neither suited to the perceptible climate variability nor the rapid pace of urbanization sweeping the country. Flood prediction, from short-term (a few hours) to medium-term (a few days), needs to be revisited and adapted to changing socio-economic and hydro-climatic realities. The latest technology requires implementation of multiple numerical weather prediction systems. The availability of twelve global ensemble weather prediction systems through the ‘THORPEX Interactive Grand Global Ensemble' (TIGGE) offers a good opportunity for an effective state-of-the-art early forecasting system. A prototype of a Novel Flood Early Warning System (NEWS) using the TIGGE database is tested in the Huai River basin in east-central China. It is the first early flood warning system in China that uses the massive TIGGE database cascaded with river catchment models, the Xinanjiang hydrologic model and a 1-D hydraulic model, to predict river discharge and flood inundation. The NEWS algorithm is also designed to provide web-based services to a broad spectrum of end-users. The latter presents challenges as both databases and proprietary codes reside in different locations and converge at dissimilar times. NEWS will thus make use of a ready-to-run grid system that makes distributed computing and data resources available in a seamless and secure way. An ability to run or function on different operating systems and provide an interface or front that is accessible to broad spectrum of end-users is additional requirement. The aim is to achieve robust interoperability through strong security and workflow capabilities. A physical network diagram and a work flow scheme of all the models, codes and databases used to achieve the NEWS algorithm are presented. They constitute a first step in the development of a platform for providing real time flood forecasting services on the web to mitigate 21st century weather phenomena.
NASA Astrophysics Data System (ADS)
Gilligan, J. M.; Corey, B.; Camp, J. V.; John, N. J.; Sengupta, P.
2015-12-01
The complex interactions between land use and natural hazards pose serious challenges in education, research, and public policy. Where complex nonlinear interactions produce unintuitive results, interactive computer simulations can be useful tools for education and decision support. Emotions play important roles in cognition and learning, especially where risks are concerned. Interactive simulations have the potential to harness emotional engagement to enhance learning and understanding of risks in coupled human-natural systems. We developed a participatory agent-based simulation of cities at risk of river flooding. Participants play the role of managers of neighboring cities along a flood-prone river and make choices about building flood walls to protect their inhabitants. Simulated agents participate in dynamic real estate markets in which demand for property, and thus values and decisions to build, respond to experience with flooding over time. By reducing high-frequency low-magnitude flooding, flood walls may stimulate development, thus increasing tax revenues but also increasing vulnerability to uncommon floods that overtop the walls. Flood waves are launched stochastically and propagate downstream. Flood walls that restrict overbank flow at one city can increase the amplitude of a flood wave at neighboring cities, both up and downstream. We conducted a pilot experiment with a group of three pre-service teachers. The subjects successfully learned key concepts of risk tradeoffs and unintended consequences that can accompany flood-control measures. We also observed strong emotional responses, including hope, fear, and sense of loss. This emotional engagement with a model of coupled human-natural systems was very different from previous experiments on participatory simulations of purely natural systems for physics pedagogy. We conducted a second session in which the participants were expert engineers. We will present the results of these experiments and the prospects for using such models for middle-school, high-school, and post-secondary environmental science pedagogy, for improving public understanding of flood risks, and as decision support tools for planners.
Normalised flood losses in Europe: 1970-2006
NASA Astrophysics Data System (ADS)
Barredo, J. I.
2009-02-01
This paper presents an assessment of normalised flood losses in Europe for the period 1970-2006. Normalisation provides an estimate of the losses that would occur if the floods from the past take place under current societal conditions. Economic losses from floods are the result of both societal and climatological factors. Failing to adjust for time-variant socio-economic factors produces loss amounts that are not directly comparable over time, but rather show an ever-growing trend for purely socio-economic reasons. This study has used available information on flood losses from the Emergency Events Database (EM-DAT) and the Natural Hazards Assessment Network (NATHAN). Following the conceptual approach of previous studies, we normalised flood losses by considering the effects of changes in population, wealth, and inflation at the country level. Furthermore, we removed inter-country price differences by adjusting the losses for purchasing power parities (PPP). We assessed normalised flood losses in 31 European countries. These include the member states of the European Union, Norway, Switzerland, Croatia, and the Former Yugoslav Republic of Macedonia. Results show no detectable sign of human-induced climate change in normalised flood losses in Europe. The observed increase in the original flood losses is mostly driven by societal factors.
'System-Risk' Flood Task Force
NASA Astrophysics Data System (ADS)
Schröter, Kai; Ridder, Nina; Tavares da Costa, Ricardo; Diederen, Dirk; Viglione, Alberto
2017-04-01
Current scientific methods and engineering practice in flood risk assessment do not consider the full complexity of flood risk systems. Fundamental spatio-temporal dependencies, interactions and feedbacks need to be addressed to comprehensively quantify the effects of measures at various levels, ranging from local technical to high-level policy options. As each flood is unique, each event offers an unparalleled opportunity to collect data and to gain insights into system's behavior under extreme conditions potentially revealing exceptional circumstances, unexpected failures and cascading effects, and thus a chance to learn and to improve methods and models. To make use of this the Marie-Skłodowska-Curie European Training Network 'System-Risk' (www.system-risk.eu) establishes a Flood Task Force (FTF) that aims to learn about successful practical approaches, but also potential pitfalls and failures in the management of real flood events. The FTF consists of an interdisciplinary group of researchers who will apply in situ their latest methods and knowledge of e.g. how the event developed, how the risk management responded, and what the consequences were. This multi-layered perspective is intended to deepen the understanding of the complexity of flood risk systems as for instance in terms of interactions between hazard, the natural and the built environment, societal institutions and coping capacities. This contribution gives an overview of the conceptual approach to the System-Risk FTF.
NASA Astrophysics Data System (ADS)
Cooper, J. A. G.
2002-06-01
Contrasting modes of sedimentation and facies arrangement in tide- and river-dominated microtidal estuaries arise from the degree to which river or tidal discharge and sediment supply influences an estuary. A distinct facies gradation exists in tide-dominated systems from sandy, barrier/tidal delta-associated environments at the coast through deep mud-dominated middle reaches to fluvial sediment in the upper reaches. In river-dominated systems, fluvial sediment extends to the barrier and flood-tidal deltas are poorly developed or absent from the estuary. A number of independent observations during extreme floods on the South African coast indicate that these types of estuary respond differently to extreme river floods and that the mode of response corresponds to estuary type. Tide-dominated systems exhibit preferential erosion of noncohesive barrier and tidal delta sediments during river floods while the middle reaches remain little modified. River-dominated systems experience consistent erosion throughout their channel length during extreme floods. The increased cohesion of riverine sediments and stabilisation of bars by vegetation in river-dominated channels means that higher magnitude floods are necessary to effect significant morphological change. Barrier erosion, including the tidal delta, results in deposition of an ephemeral delta composed almost entirely of sands from these deposits in tide-dominated estuaries. In river-dominated systems, eroded channel sediments and material from the river catchment may augment barrier sediments in the ephemeral delta deposit. Post-flood, wave-reworking of ephemeral delta sediments acts to restore barriers to pre-flood morphology within a few years; however, in river-dominated systems, the additional sediment volume may produce significant coastal progradation that requires several years or decades to redistribute. These different modes of flood response mediated by the nature of the estuary have implications for coastal behaviour at the time scale of months to several decades. Estuary-coastal behaviour at river-dominated estuaries may be influenced for several decades by post-flood morphological adjustment. Tide-dominated estuaries, however, respond more rapidly in reworking flood-eroded sediment and are typically fully adjusted to modal wave and tidal conditions within a few months to a few years. In addition, the facies arrangement within the two estuary types renders tide-dominated estuaries more responsive to minor floods, while river-dominated estuaries, by virtue of more cohesive channel sediments, require greater discharges to effect significant morphological change.
Early Flood Warning in Africa: Results of a Feasibility study in the JUBA, SHABELLE and ZAMBEZI
NASA Astrophysics Data System (ADS)
Pappenberger, F. P.; de Roo, A. D.; Buizza, Roberto; Bodis, Katalin; Thiemig, Vera
2009-04-01
Building on the experiences gained with the European Flood Alert System (EFAS), pilot studies are carried out in three river basins in Africa. The European Flood Alert System, pre-operational since 2003, provides early flood alerts for European rivers. At present, the experiences with the European EFAS system are used to evaluate the feasibility of flood early warning for Africa. Three case studies are carried in the Juba and Shabelle rivers (Somalia and Ethiopia), and in the Zambesi river (Southern Africa). Predictions in these data scarce regions are extremely difficult to make as records of observations are scarce and often unreliable. Meteorological and Discharge observations are used to calibrate and test the model, as well as soils, landuse and topographic data available within the JRC African Observatory. ECMWF ERA-40, ERA-Interim data and re-forecasts of flood events from January to March 1978, and in March 2001 are evaluated to examine the feasibility for early flood warning. First results will be presented.
Flood routing of the Maja outflow across Xanthe Terra
NASA Technical Reports Server (NTRS)
Dehon, R. A.
1991-01-01
The object is to trace a single flood crest through the Maja outflow system and to evaluate the effects of topography on ponding and multiple channel routing. Maja Valles provides a good model because it has a single source and a well defined channel system. The 1500 km long Maja Valles originates in Juventae Chasma. The outflow system stretches 1100 km northward along the Lunae Planum/Xanthe Terra boundary, then eastward across the Xanthe Terra highlands. It descends to Chryse Planitia where it extends northeastward toward the middle of the basin. It is concluded that flood routing through multiple channels and retardation in local impoundments are responsible for breakup of the initial flood crest and the formation of multiple flood crests. Recombined flow near the mouths of these canyons results in an extended flow regime and multiple flood surges. As a result of ponding along the flood course, depositional sites are localized and renewed erosion downstream (from ponded sites) results in sediment source areas not greatly removed from depositional sites.
Flood Risk Assessments of Architectural Heritage - Case of Changgyeonggung Palace
NASA Astrophysics Data System (ADS)
Lee, Hyosang; Kim, Ji-sung; Lee, Ho-jin
2014-05-01
The risk of natural disasters such as flood and earthquake has increased due to recent extreme weather events. Therefore, the necessity of the risk management system to protect architectural properties, a cultural heritage of humanity, from natural disasters has been consistently felt. The solutions for managing flood risk focusing on architectural heritage are suggested and applied to protect Changgyeonggung Palace, a major palace heritage in Seoul. After the probable rainfall scenario for risk assessment (frequency: 100 years, 200 years, and 500 years) and the scenario of a probable maximum precipitation (PMP) are made and a previous rainfall event (from July 26th to 28th in 2011) is identified, they are used for the model (HEC-HMS, SWMM) to assess flood risk of certain areas covering Changgyeonggung Palace to do flood amount. Such flood amount makes it possible to identify inundation risks based on GIS models to assess flood risk of individual architectural heritage. The results of assessing such risk are used to establish the disaster risk management system that managers of architectural properties can utilize. According to the results of assessing flood risk of Changgyeonggung Palace, inundation occurs near outlets of Changgyeonggung Palace and sections of river channel for all scenarios of flood risk but the inundation risk of major architectural properties was estimated low. The methods for assessing flood risk of architectural heritage proposed in this study and the risk management system for Changgyeonggung Palace using the methods show thorough solutions for flood risk management and the possibility of using the solutions seems high. A comprehensive management system for architectural heritage will be established in the future through the review on diverse factors for disasters.
Gündoğdu, Sedat; Çevik, Cem; Ayat, Berna; Aydoğan, Burak; Karaca, Serkan
2018-08-01
Floods caused by heavy rain carry significant amounts of pollutants into marine environments. This study evaluates the effect of multiple floods that occurred in the northeastern Mediterranean region in Turkey between December 2016 and January 2017 on the microplastic pollution in the Mersin Bay. Sampling was repeated in four different stations both before and after the flood period, and it was determined that in the four stations, there was an average of 539,189 MPs/km 2 before the flood, and 7,699,716 MPs/km 2 afterwards, representing a 14-fold increase. Fourteen different polymer types were detected in an ATR FT-IR analysis, eight of which were not found in samples collected before the floods. The most common polymer type was identified as polyethylene both pre- and post-flood. The mean particle size, which was 2.37 mm in the pre-flood period, decreased to 1.13 mm in the post-flood period. A hydrodynamic modeling study was implemented to hindcast the current structure and the spatial and temporal distributions of microplastics within the study area. In conclusion, heavy rain and severe floods can dramatically increase the microplastic levels in the sea. Copyright © 2018 Elsevier Ltd. All rights reserved.
Healthcare-associated infections and their prevention after extensive flooding.
Apisarnthanarak, Anucha; Warren, David K; Mayhall, Clovus Glen
2013-08-01
This review will focus on the epidemiology of healthcare-associated infections (HAIs) after extensive blackwater flooding as well as preventive measures. There is evidence suggesting an increased incidence of HAIs and pseudo-outbreaks due to molds after extensive flooding in healthcare facilities. However, there is no strong evidence of an increased incidence of typical nosocomial infections (i.e., ventilator-associated pneumonia, healthcare-associated pneumonia, central line-associated bloodstream infection and catheter-associated urinary tract infections). The prevalence of multidrug-resistant organisms may decrease after extensive flooding, due to repeated and thorough environmental cleaning prior to re-opening hospitals. Contamination of hospital water sources by enteric Gram-negative bacteria (e.g., Aeromonas species), Legionella species and nontuberculous Mycobacterium species in flood-affected hospitals has been reported. Surveillance is an important initial step to detect potential outbreaks/pseudo-outbreaks of HAIs. Hospital preparedness policies before extensive flooding, particularly with environmental cleaning and mold remediation, are key to reducing the risk of flood-related HAIs. These policies are still lacking in most hospitals in countries that have experienced or are at risk for extensive flooding, which argues for nationwide policies to strengthen preparedness planning. Additional studies are needed to evaluate the epidemiology of flood-related HAIs and the optimal surveillance and control methods following extensive flooding.
Effects of wastewater on forested wetlands
Doyle, Thomas W.
2002-01-01
Cycling nutrient-enriched wastewater from holding ponds through natural, forested wetlands is a practice that municipal waste treatment managers are considering as a viable option for disposing of wastewater. In this wastewater cycling process, sewer effluent that has been circulated through aerated ponds is discharged into neighboring wetland systems. To understand how wastewater cycling affects forest and species productivity, researchers at the USGS National Wetlands Research Center conducted dendroecological investigations in a swamp system and in a bog system that have been exposed to wastewater effluent for many decades. Dendroecology involves the study of forest changes over time as interpreted from tree rings. Tree-ring chronologies describe the pattern and history of growth suppression and release that can be associated with aging and disturbances such as hurricanes, floods, and fires. But because of limited monitoring, little is known about the potential for long-term effects on forested wetlands as a result of wastewater flooding. USGS researchers used tree rings to detect the effect of wastewater cycling on tree growth. Scientists expected to find that tree-ring width would be increased as a result of added nutrients.
NASA Technical Reports Server (NTRS)
Adler, Robert
2007-01-01
Floods impact more people globally than any other type of natural disaster. It has been established by experience that the most effective means to reduce the property damage and life loss caused by floods is the development of flood early warning systems. However, advances for such a system have been constrained by the difficulty in estimating rainfall continuously over space (catchment-. national-, continental-. or even global-scale areas) and time (hourly to daily). Particularly, insufficient in situ data, long delay in data transmission and absence of real-time data sharing agreements in many trans-boundary basins hamper the development of a real-time system at the regional to global scale. In many countries around the world, particularly in the tropics where rainfall and flooding co-exist in abundance, satellite-based precipitation estimation may be the best source of rainfall data for those data scarce (ungauged) areas and trans-boundary basins. Satellite remote sensing data acquired and processed in real time can now provide the space-time information on rainfall fluxes needed to monitor severe flood events around the world. This can be achieved by integrating the satellite-derived forcing data with hydrological models, which can be parameterized by a tailored geospatial database. An example that is a key to this progress is NASA's contribution to the Tropical Rainfall Measuring Mission (TRMM), launched in November 1997. Hence, in an effort to evolve toward a more hydrologically-relevant flood alert system, this talk articulates a module-structured framework for quasi-global flood potential naming, that is 'up to date' with the state of the art on satellite rainfall estimation and the improved geospatial datasets. The system is modular in design with the flexibility that permits changes in the model structure and in the choice of components. Four major components included in the system are: 1) multi-satellite precipitation estimation; 2) characterization of land surface including digital elevation from NASA SRTM, topography-derived hydrologic parameters such as flood direction. flow accumulation, basin, and river network etc.; 3) spatially distributed hydrological models to infiltrate rainfall and route overland runoff; and 4) an implementation interface to relay thc input data to the models and display the flood inundation results to the users and decision-makers. Early results appear reasonable in terms of location and frequency of events. Case studies of this experimental system are evaluated with surface runoff data and other river monitoring systems. such as Dartmouth Flood Observatory's "Surface Water Watch" array of river reaches that are measured daily via other satellite remote sensing data. A major outcome of this progress will be the availability of a global overview of flood alerts that should consequently improve the performance of Decision Support System. We expect these developments in utilization of satellite remote sensing technology to offer a practical solution to the challenge of building a cost-effective early warning system for data scarce and under-developed areas.
An overview of road damages due to flooding: Case study in Kedah state, Malaysia
NASA Astrophysics Data System (ADS)
Ismail, Muhd Shahril Nizam; Ghani, Abdul Naser Abdul
2017-10-01
Flooding occurs frequently in many countries including Malaysia. Floods in Malaysia are usually due to heavy and prolonged rainfall, uncontrolled development, and drainage systems that are not being monitored. Road damage due to flooding event can cause huge expenditures for the post-flooding rehabilitation and maintenance. The required maintenance and rehabilitation could upset the original life cycle cost estimations. Data on road statistics were obtained from the Highway Planning Division, Ministry of Works Malaysia and data on flooding was collected from the Department of Irrigation and Drainage Malaysia for events between 2012 and 2015. The pilot sites were selected based on its historical cases of floods that caused road damages in Kedah. The pilot site indicated that the impact of flooding on road infrastructures systems can be used to plan better road design and maintenances. It also revealed that it costs more than RM 1 million to reinstate roads damaged by flooding in a typical district annually.
NASA Astrophysics Data System (ADS)
Sung, K.; Jeong, H.; Sangwan, N.; Yu, D. J.
2017-12-01
Human societies have tried to prevent floods by building robust infrastructure such as levees or dams. However, some scholars raise a doubt to this approach because of a lack of adaptiveness to environmental and societal changes in a long-term. Thus, a growing number of studies now suggest adopting new strategies in flood management to reinforce an adapt capacity to the long-term flood risk. This study addresses this issue by developing a conceptual mathematical model exploring how flood management strategies effect to the dynamics human-flood interaction, ultimately the flood resilience in a long-term. Especially, our model is motivated by the community-based flood protection system in southwest coastal area in Bangladesh. We developed several conceptual flood management strategies and investigated the interplay between those strategies and community's capacity to cope with floods. We additionally analyzed how external disturbances (sea level rise, water tide level change, and outside economic development) alter the adaptive capacity to flood risks. The results of this study reveal that the conventional flood management has potential vulnerabilities as external disturbances increase. Our results also highlight the needs of the adaptive strategy as a new paradigm in flood management which is able to feedback to the social and hydrological conditions. These findings provide insights on the resilience-based, adaptive strategies which can build flood resilience under global change.
12 CFR 614.4940 - Required use of standard flood hazard determination form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Required use of standard flood hazard... LOAN POLICIES AND OPERATIONS Flood Insurance Requirements § 614.4940 Required use of standard flood hazard determination form. (a) Use of form. System institutions must use the standard flood hazard...
Satellites, tweets, forecasts: the future of flood disaster management?
NASA Astrophysics Data System (ADS)
Dottori, Francesco; Kalas, Milan; Lorini, Valerio; Wania, Annett; Pappenberger, Florian; Salamon, Peter; Ramos, Maria Helena; Cloke, Hannah; Castillo, Carlos
2017-04-01
Floods have devastating effects on lives and livelihoods around the world. Structural flood defence measures such as dikes and dams can help protect people. However, it is the emerging science and technologies for flood disaster management and preparedness, such as increasingly accurate flood forecasting systems, high-resolution satellite monitoring, rapid risk mapping, and the unique strength of social media information and crowdsourcing, that are most promising for reducing the impacts of flooding. Here, we describe an innovative framework which integrates in real-time two components of the Copernicus Emergency mapping services, namely the European Flood Awareness System and the satellite-based Rapid Mapping, with new procedures for rapid risk assessment and social media and news monitoring. The integrated framework enables improved flood impact forecast, thanks to the real-time integration of forecasting and monitoring components, and increases the timeliness and efficiency of satellite mapping, with the aim of capturing flood peaks and following the evolution of flooding processes. Thanks to the proposed framework, emergency responders will have access to a broad range of timely and accurate information for more effective and robust planning, decision-making, and resource allocation.
Prone to fix: Resilience of the active nitrogen-fixing rice root microbiome
NASA Astrophysics Data System (ADS)
Hurek, Thomas; Sabale, Mugdha; Sarkar, Abhijit; Pees, Tobias; Reinhold-Hurek, Barbara
2016-04-01
Due to water consumption, many lowland rice areas in Asia are undergoing a transition that involves adoption of new management strategies, with crop rotations encompassing a non-flooded crop, including maize. Shifting from flooded to non-flooded cropping is likely to affect microbial nitrogen cycling. For analysis of the root-associated microbiome of rice and maize in response to flooding or nitrogen fertilizer, we combine methods of microbial ecology (Next-Generation sequencing of amplicons), and a reductionist approach with pure cultures of the endophytic diazotroph Azoarus sp.. Field plots of the ICON project (Introducing non-flooded crops in rice-dominated landscapes: Impact on Carbon, nitrogen and water budgets) at the International Rice Research Institute in the Philippines were analyzed. Root-associated activity of nitrogenase gene expression was assessed by quantitative RT-PCR of nifH. For rice, expression levels were surprisingly stable, in response to non-flooded versus flooded conditions, or in response to conventional nitrogen fertilizer applications versus lack of N-fertilizer. In contrast, the active diazotrophic population of maize roots was not resistant to N-fertilization, nifH expression strongly decreased. Concordant changes in the diazotrophic resident or active communities were detected by nifH amplicon sequence analysis, based on bacterial DNA or mRNA, respectively. For high-resolution analyses of the endobiome in gnotobiotic culture, we developed a dual fluorescence reporter system for Azoarcus sp. BH72 which allows to quantify and visualize epi- and endophytic gene expression by concfocal microscopy (CLSM). This allowed us to demonstrate sites of active nitrogen fixation (gene expression) in association with rice roots. We confirmed that at low nitrogen fertilizer levels, endophytic nifH gene expression persisted in rice roots, while it was repressed in maize roots. This supports our observation of remarkable stability of nitrogen fixation in association with rice roots.
NASA Astrophysics Data System (ADS)
Radosavljevic, B.; Lantuit, H.; Overduin, P. P.; Fritz, M.
2015-12-01
Coastal infrastructure, cultural, and archeological sites are increasingly vulnerable to erosion and flooding along permafrost coasts. Amplified warming of the Arctic, sea level rise, lengthening of the open water period, and a predicted increase in frequency of major storms compound these threats. Mitigation necessitates decision-making tools at an appropriate scale. We present a study of coastal erosion combining it with a flooding risk assessment for the culturally important historic settlement on Herschel Island, a UNESCO World Heritage candidate site. The resulting map may help local stakeholders devise management strategies to cope with rapidly changing environmental conditions. We analyzed shoreline movement using the Digital Shoreline Analysis System (DSAS) after digitizing shorelines from 1952, 1970, and 2011. Using these data, forecasts of shoreline positions were made for 20 and 50 years into the future. Flooding risk was assessed using a cost-distance map based on a high-resolution Light Detection and Ranging (LiDAR) dataset and current Intergovernmental Panel on Climate Change sea level estimates. Widespread erosion characterizes the study area. The rate of shoreline movement for different periods of the study ranges from -5.5 to 2.7 m·a-1 (mean -0.6 m·a-1). Mean coastal retreat decreased from -0.6 m·a-1 to -0.5 m·a-1, for 1952-1970 and 1970-2000, respectively, and increased to -1.3 m·a-1 in the period 2000-2011. Ice-rich coastal sections, and coastal sections most exposed to wave attack exhibited the highest rates of coastal retreat. The geohazard map resulting from shoreline projections and flood risk analysis indicates that most of the area occupied by the historic settlement is at extreme or very high risk of flooding, and some buildings are vulnerable to coastal erosion. The results of this study indicate a greater threat by coastal flooding than erosion. Our assessment may be applied in other locations where limited data are available.
Modeling human-flood interactions: Collective action and community resilience.
NASA Astrophysics Data System (ADS)
Yu, D. J.; Sangwan, N.; Sung, K.
2016-12-01
Stylized models of socio-hydrology have mainly used social memory aspects such as community awareness or sensitivity to connect hydrologic change and social response. However, social memory alone does not satisfactorily capture the details of how human behavior is translated into collective action for water resources governance. Nor is it the only mechanism by which the two-way feedbacks of socio-hydrology can be operationalized. This study contributes towards bridging of this gap by developing a stylized model of a human-flood system that includes two additional drivers of change: (1) institutions for collective action, and (2) connections to an external economic system. Motivated by the case of community-managed flood protection systems (polders) in coastal Bangladesh, we use the model to understand critical general features that affect long-term resilience of human-flood systems. Our findings suggest that occasional adversity can enhance long-term resilience. Allowing some hydrological variability to enter into the polder can increase its adaptive capacity and resilience through the preservation of social memory and institutions for collective action. Further, there are potential tradeoffs associated with optimization of flood resilience through structural measures. By reducing sensitivity to flooding, the system may become more fragile under the double impact of flooding and economic change
Hardmeyer, Kent; Spencer, Michael A
2007-04-01
This article provides an overview of the use of risk-based analysis (RBA) in flood damage assessment, and it illustrates the use of Geographic Information Systems (GIS) in identifying flood-prone areas, which can aid in flood-mitigation planning assistance. We use RBA to calculate expected annual flood damages in an urban watershed in the state of Rhode Island, USA. The method accounts for the uncertainty in the three primary relationships used in computing flood damage: (1) the probability that a given flood will produce a given amount of floodwater, (2) the probability that a given amount of floodwater will reach a certain stage or height, and (3) the probability that a certain stage of floodwater will produce a given amount of damage. A greater than 50% increase in expected annual flood damage is estimated for the future if previous development patterns continue and flood-mitigation measures are not taken. GIS is then used to create a map that shows where and how often floods might occur in the future, which can help (1) identify priority areas for flood-mitigation planning assistance and (2) disseminate information to public officials and other decision-makers.
Surface Flooding from Hurricane Harvey Shown in New SMAP Imagery
2017-08-30
A new series of images generated with data from NASA's Soil Moisture Active Passive (SMAP) satellite illustrate the surface flooding caused by Hurricane Harvey from before its initial landfall through August 27, 2017. The SMAP observations detect the proportion of the ground covered by surface water within the satellite's field of view. The sequence of images depicts successive satellite orbital swath observations showing the surface water conditions on August 22, before Harvey's landfall (left), and then on Aug. 27, two days after landfall (middle). The resulting increase in surface flooding from record rainfall over the three-day period, shown at right, depicts regionally heavy flooding around the Houston metropolitan area. The hardest hit areas (blue and purple shades) cover more than 23,000 square miles (about 59,600 square kilometers) and indicate a more than 1,000-fold increase in surface water cover from rainfall-driven flooding. SMAP's low-frequency (L-band) microwave radiometer features enhanced capabilities for detecting surface water changes in nearly all weather conditions and under low-to-moderate vegetation cover. The satellite provides global coverage with one to three-day repeat sampling, which is well suited for monitoring dynamic inland waters around the world. https://photojournal.jpl.nasa.gov/catalog/PIA21930
NASA Astrophysics Data System (ADS)
Li, C.-H.; Li, N.; Wu, L.-C.; Hu, A.-J.
2013-07-01
The vulnerability to flood disaster is addressed by a number of studies. It is of great importance to analyze the vulnerability of different regions and various periods to enable the government to make policies for distributing relief funds and help the regions to improve their capabilities against disasters, yet a recognized paradigm for such studies seems missing. Vulnerability is defined and evaluated through either physical or economic-ecological perspectives depending on the field of the researcher concerned. The vulnerability, however, is the core of both systems as it entails systematic descriptions of flood severities or disaster management units. The research mentioned often has a development perspective, and in this article we decompose the overall flood system into several factors: disaster driver, disaster environment, disaster bearer, and disaster intensity, and take the interaction mechanism among all factors as an indispensable function. The conditions of flood disaster components are demonstrated with disaster driver risk level, disaster environment stability level and disaster bearer sensitivity, respectively. The flood system vulnerability is expressed as vulnerability = f(risk, stability, sensitivity). Based on the theory, data envelopment analysis method (DEA) is used to detail the relative vulnerability's spatiotemporal variation of a flood disaster system and its components in the Dongting Lake region. The study finds that although a flood disaster system's relative vulnerability is closely associated with its components' conditions, the flood system and its components have a different vulnerability level. The overall vulnerability is not the aggregation of its components' vulnerability. On a spatial scale, zones central and adjacent to Dongting Lake and/or river zones are characterized with very high vulnerability. Zones with low and very low vulnerability are mainly distributed in the periphery of the Dongting Lake region. On a temporal scale, the occurrence of a vibrating flood vulnerability trend is observed. A different picture is displayed with the disaster driver risk level, disaster environment stability level and disaster bearer sensitivity level. The flood relative vulnerability estimation method based on DEA is characteristic of good comparability, which takes the relative efficiency of disaster system input-output into account, and portrays a very diverse but consistent picture with varying time steps. Therefore, among different spatial and time domains, we could compare the disaster situations with what was reflected by the same disaster. Additionally, the method overcomes the subjectivity of a comprehensive flood index caused by using an a priori weighting system, which exists in disaster vulnerability estimation of current disasters.
Database assessment of CMIP5 and hydrological models to determine flood risk areas
NASA Astrophysics Data System (ADS)
Limlahapun, Ponthip; Fukui, Hiromichi
2016-11-01
Solutions for water-related disasters may not be solved with a single scientific method. Based on this premise, we involved logic conceptions, associate sequential result amongst models, and database applications attempting to analyse historical and future scenarios in the context of flooding. The three main models used in this study are (1) the fifth phase of the Coupled Model Intercomparison Project (CMIP5) to derive precipitation; (2) the Integrated Flood Analysis System (IFAS) to extract amount of discharge; and (3) the Hydrologic Engineering Center (HEC) model to generate inundated areas. This research notably focused on integrating data regardless of system-design complexity, and database approaches are significantly flexible, manageable, and well-supported for system data transfer, which makes them suitable for monitoring a flood. The outcome of flood map together with real-time stream data can help local communities identify areas at-risk of flooding in advance.
REAL-TIME high-resolution urban surface water flood mapping to support flood emergency management
NASA Astrophysics Data System (ADS)
Guan, M.; Yu, D.; Wilby, R.
2016-12-01
Strong evidence has shown that urban flood risks will substantially increase because of urbanisation, economic growth, and more frequent weather extremes. To effectively manage these risks require not only traditional grey engineering solutions, but also a green management solution. Surface water flood risk maps based on return period are useful for planning purposes, but are limited for application in flood emergencies, because of the spatiotemporal heterogeneity of rainfall and complex urban topography. Therefore, a REAL-TIME urban surface water mapping system is highly beneficial to increasing urban resilience to surface water flooding. This study integrated numerical weather forecast and high-resolution urban surface water modelling into a real-time multi-level surface water mapping system for Leicester City in the UK. For rainfall forecast, the 1km composite rain radar from the Met Office was used, and we used the advanced rainfall-runoff model - FloodMap to predict urban surface water at both city-level (10m-20m) and street-level (2m-5m). The system is capable of projecting 3-hour urban surface water flood, driven by rainfall derived from UK Met Office radar. Moreover, this system includes real-time accessibility mapping to assist the decision-making of emergency responders. This will allow accessibility (e.g. time to travel) from individual emergency service stations (e.g. Fire & Rescue; Ambulance) to vulnerable places to be evaluated. The mapping results will support contingency planning by emergency responders ahead of potential flood events.
NASA Astrophysics Data System (ADS)
Kourgialas, N. N.; Karatzas, G. P.
2014-03-01
A modeling system for the estimation of flash flood flow velocity and sediment transport is developed in this study. The system comprises three components: (a) a modeling framework based on the hydrological model HSPF, (b) the hydrodynamic module of the hydraulic model MIKE 11 (quasi-2-D), and (c) the advection-dispersion module of MIKE 11 as a sediment transport model. An important parameter in hydraulic modeling is the Manning's coefficient, an indicator of the channel resistance which is directly dependent on riparian vegetation changes. Riparian vegetation's effect on flood propagation parameters such as water depth (inundation), discharge, flow velocity, and sediment transport load is investigated in this study. Based on the obtained results, when the weed-cutting percentage is increased, the flood wave depth decreases while flow discharge, velocity and sediment transport load increase. The proposed modeling system is used to evaluate and illustrate the flood hazard for different riparian vegetation cutting scenarios. For the estimation of flood hazard, a combination of the flood propagation characteristics of water depth, flow velocity and sediment load was used. Next, a well-balanced selection of the most appropriate agricultural cutting practices of riparian vegetation was performed. Ultimately, the model results obtained for different agricultural cutting practice scenarios can be employed to create flood protection measures for flood-prone areas. The proposed methodology was applied to the downstream part of a small Mediterranean river basin in Crete, Greece.
Incorporating institutions and collective action into a sociohydrological model of flood resilience
NASA Astrophysics Data System (ADS)
Yu, David J.; Sangwan, Nikhil; Sung, Kyungmin; Chen, Xi; Merwade, Venkatesh
2017-02-01
Stylized sociohydrological models have mainly used social memory aspects such as community awareness or sensitivity to connect hydrologic change and social response. However, social memory alone does not satisfactorily capture the details of how human behavior is translated into collective action for water resources governance. Nor is it the only social mechanism by which the two-way feedbacks of sociohydrology can be operationalized. This study contributes toward bridging of this gap by developing a sociohydrological model of a flood resilience that includes two additional components: (1) institutions for collective action, and (2) connections to an external economic system. Motivated by the case of community-managed flood protection systems (polders) in coastal Bangladesh, we use the model to understand critical general features that affect long-term resilience of human-flood systems. Our findings suggest that occasional adversity can enhance long-term resilience. Allowing some hydrological variability to enter into the polder can increase its adaptive capacity for resilience through the preservation of social norm for collective action. Further, there are potential trade-offs associated with optimization of flood resistance through structural measures. By reducing sensitivity to floods, the system may become more fragile under the double impact of floods and economic change.
Haj, Adel E.; Christiansen, Daniel E.; Viger, Roland J.
2014-01-01
In 2011 the Missouri River Mainstem Reservoir System (Reservoir System) experienced the largest volume of flood waters since the initiation of record-keeping in the nineteenth century. The high levels of runoff from both snowpack and rainfall stressed the Reservoir System’s capacity to control flood waters and caused massive damage and disruption along the river. The flooding and resulting damage along the Missouri River brought increased public attention to the U.S. Army Corps of Engineers (USACE) operation of the Reservoir System. To help understand the effects of Reservoir System operation on the 2011 Missouri River flood flows, the U.S. Geological Survey Precipitation-Runoff Modeling System was used to construct a model of the Missouri River Basin to simulate flows at streamgages and dam locations with the effects of Reservoir System operation (regulation) on flow removed. Statistical tests indicate that the Missouri River Precipitation-Runoff Modeling System model is a good fit for high-flow monthly and annual stream flow estimation. A comparison of simulated unregulated flows and measured regulated flows show that regulation greatly reduced spring peak flow events, consolidated two summer peak flow events to one with a markedly decreased magnitude, and maintained higher than normal base flow beyond the end of water year 2011. Further comparison of results indicate that without regulation, flows greater than those measured would have occurred and been sustained for much longer, frequently in excess of 30 days, and flooding associated with high-flow events would have been more severe.
Understanding Flood Seasonality and Its Temporal Shifts within the Contiguous United States
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Sheng; Li, Hong-Yi; Leung, L. Ruby
2017-07-01
Understanding the causes of flood seasonality is critical for better flood management. This study examines the seasonality of annual maximum floods (AMF) and its changes before and after 1980 at over 250 natural catchments across the contiguous United States. Using circular statistics to define a seasonality index, our analysis focuses on the variability of the flood occurrence date. Generally, catchments with more synchronized seasonal water and energy cycles largely inherit their seasonality of AMF from that of annual maximum rainfall (AMR). In contrast, the seasonality of AMF in catchments with loosely synchronized water and energy cycles are more influenced bymore » high antecedent storage, which is responsible for the amplification of the seasonality of AMF over that of AMR. This understanding then effectively explains a statistically significant shift of flood seasonality detected in some catchments in the recent decades. Catchments where the antecedent soil water storage has increased since 1980 exhibit increasing flood seasonality while catchments that have experienced increases in storm rainfall before the floods have shifted towards floods occurring more variably across the seasons. In the eastern catchments, a concurrent widespread increase in event rainfall magnitude and reduced soil water storage have led to a more variable timing of floods. Our findings of the role of antecedent storage and event rainfall on the flood seasonality provide useful insights for understanding future changes in flood seasonality as climate models projected changes in extreme precipitation and aridity over land.« less
Argus, R E; Colmer, T D; Grierson, P F
2015-06-01
We investigated physiological and morphological responses to flooding and recovery in Eucalyptus camaldulensis subsp. refulgens, a riparian tree species from a dryland region prone to intense episodic floods. Seedlings in soil flooded for 88 d produced extensive adventitious roots, displayed stem hypertrophy (stem diameter increased by 93%) and increased root porosity owing to aerenchyma formation. Net photosynthesis (Pn) and stomatal conductance (gs) were maintained for at least 2 weeks of soil flooding, contrasting with previous studies of other subspecies of E. camaldulensis. Gradual declines followed in both gs (30% less than controls) and Pn (19% less). Total leaf soluble sugars did not differ between flooded and control plants. Root mass did not recover 32 d after flooding ceased, but gs was not lower than controls, suggesting the root system was able to functionally compensate. However, the limited root growth during recovery after flooding was surprising given the importance of extensive root systems in dryland environments. We conclude that early flood tolerance could be an adaptation to capitalize on scarce water resources in a water-limited environment. Overall, our findings highlight the need to assess flooding responses in relation to a species' fitness for particular flood regimes or ecological niches. © 2014 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Comer, Joanne; Indiana Olbert, Agnieszka; Nash, Stephen; Hartnett, Michael
2017-02-01
Urban developments in coastal zones are often exposed to natural hazards such as flooding. In this research, a state-of-the-art, multi-scale nested flood (MSN_Flood) model is applied to simulate complex coastal-fluvial urban flooding due to combined effects of tides, surges and river discharges. Cork city on Ireland's southwest coast is a study case. The flood modelling system comprises a cascade of four dynamically linked models that resolve the hydrodynamics of Cork Harbour and/or its sub-region at four scales: 90, 30, 6 and 2 m. Results demonstrate that the internalization of the nested boundary through the use of ghost cells combined with a tailored adaptive interpolation technique creates a highly dynamic moving boundary that permits flooding and drying of the nested boundary. This novel feature of MSN_Flood provides a high degree of choice regarding the location of the boundaries to the nested domain and therefore flexibility in model application. The nested MSN_Flood model through dynamic downscaling facilitates significant improvements in accuracy of model output without incurring the computational expense of high spatial resolution over the entire model domain. The urban flood model provides full characteristics of water levels and flow regimes necessary for flood hazard identification and flood risk assessment.
Chowdhury, Rashed
2005-06-01
Despite advances in short-range flood forecasting and information dissemination systems in Bangladesh, the present system is less than satisfactory. This is because of short lead-time products, outdated dissemination networks, and lack of direct feedback from the end-user. One viable solution is to produce long-lead seasonal forecasts--the demand for which is significantly increasing in Bangladesh--and disseminate these products through the appropriate channels. As observed in other regions, the success of seasonal forecasts, in contrast to short-term forecast, depends on consensus among the participating institutions. The Flood Forecasting and Warning Response System (henceforth, FFWRS) has been found to be an important component in a comprehensive and participatory approach to seasonal flood management. A general consensus in producing seasonal forecasts can thus be achieved by enhancing the existing FFWRS. Therefore, the primary objective of this paper is to revisit and modify the framework of an ideal warning response system for issuance of consensus seasonal flood forecasts in Bangladesh. The five-stage FFWRS-i) Flood forecasting, ii) Forecast interpretation and message formulation, iii) Warning preparation and dissemination, iv) Responses, and v) Review and analysis-has been modified. To apply the concept of consensus forecast, a framework similar to that of the Southern African Regional Climate Outlook Forum (SARCOF) has been discussed. Finally, the need for a climate Outlook Fora has been emphasized for a comprehensive and participatory approach to seasonal flood hazard management in Bangladesh.
Securing mobile ad hoc networks using danger theory-based artificial immune algorithm.
Abdelhaq, Maha; Alsaqour, Raed; Abdelhaq, Shawkat
2015-01-01
A mobile ad hoc network (MANET) is a set of mobile, decentralized, and self-organizing nodes that are used in special cases, such as in the military. MANET properties render the environment of this network vulnerable to different types of attacks, including black hole, wormhole and flooding-based attacks. Flooding-based attacks are one of the most dangerous attacks that aim to consume all network resources and thus paralyze the functionality of the whole network. Therefore, the objective of this paper is to investigate the capability of a danger theory-based artificial immune algorithm called the mobile dendritic cell algorithm (MDCA) to detect flooding-based attacks in MANETs. The MDCA applies the dendritic cell algorithm (DCA) to secure the MANET with additional improvements. The MDCA is tested and validated using Qualnet v7.1 simulation tool. This work also introduces a new simulation module for a flooding attack called the resource consumption attack (RCA) using Qualnet v7.1. The results highlight the high efficiency of the MDCA in detecting RCAs in MANETs.
Securing Mobile Ad Hoc Networks Using Danger Theory-Based Artificial Immune Algorithm
2015-01-01
A mobile ad hoc network (MANET) is a set of mobile, decentralized, and self-organizing nodes that are used in special cases, such as in the military. MANET properties render the environment of this network vulnerable to different types of attacks, including black hole, wormhole and flooding-based attacks. Flooding-based attacks are one of the most dangerous attacks that aim to consume all network resources and thus paralyze the functionality of the whole network. Therefore, the objective of this paper is to investigate the capability of a danger theory-based artificial immune algorithm called the mobile dendritic cell algorithm (MDCA) to detect flooding-based attacks in MANETs. The MDCA applies the dendritic cell algorithm (DCA) to secure the MANET with additional improvements. The MDCA is tested and validated using Qualnet v7.1 simulation tool. This work also introduces a new simulation module for a flooding attack called the resource consumption attack (RCA) using Qualnet v7.1. The results highlight the high efficiency of the MDCA in detecting RCAs in MANETs. PMID:25946001
Musser, Jonathan W.
2012-01-01
Digital flood-inundation maps for a 5.5-mile reach of the Peachtree Creek from the Norfolk Southern Railway bridge to the Moores Mill Road NW bridge, were developed by the U.S. Geological Survey (USGS) in cooperation with the City of Atlanta, Georgia. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Peachtree Creek at Atlanta, Georgia (02336300) and the USGS streamgage at Chattahoochee River at Georgia 280, near Atlanta, Georgia (02336490). Current water level (stage) at these USGS streamgages may be obtained at http://waterdata.usgs.gov/ and can be used in conjunction with these maps to estimate near real-time areas of inundation. The National Weather Service (NWS) is incorporating results from this study into the Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that commonly are collocated at USGS streamgages. The forecasted peak-stage information for the USGS streamgage at Peachtree Creek, which is available through the AHPS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. A one-dimensional step-backwater model was developed using the U.S. Army Corps of Engineers HEC–RAS software for a 6.5-mile reach of Peachtree Creek and was used to compute flood profiles for a 5.5-mile reach of the creek. The model was calibrated using the most current stage-discharge relations at the Peachtree Creek at Atlanta, Georgia, streamgage (02336300), and the Chattahoochee River at Georgia 280, near Atlanta, Georgia, streamgage (02336490) as well as high water marks collected during the 2010 annual peak flow event. The hydraulic model was then used to determine 50 water-surface profiles. The profiles are for 10 flood stages at the Peachtree Creek streamgage at 1-foot intervals referenced to the streamgage datum and ranging from just above bankfull stage (15.0 feet) to approximately the highest recorded water level at the streamgage (24.0 feet). At each stage on Peachtree Creek, five stages at the Chattahoochee River streamgage, from 26.4 feet to 38.4 feet in 3-foot intervals, were used to determine backwater effects. The simulated water-surface profiles were then combined with a geographic information system digital elevation model—derived from Light Detection and Ranging (LiDAR) data having a 0.3-foot vertical and 16.4-foot horizontal resolution—to delineate the area flooded for each 1-foot increment of stream stage. The availability of these maps, when combined with real-time information regarding current stage from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with critical information during flood response activities, such as evacuations and road closures as well as for postflood-recovery efforts.
NASA Astrophysics Data System (ADS)
Brunck, Heiko; Sirocko, Frank; Albert, Johannes
2016-04-01
Lake sediments are excellent climate archives and can be used for reconstructions of past precipitation and flood events. However, until now, there is no continous flood record for the entire last 60 000 years for Central Europe. This study reconstructs the history of the main flood events in central Europe from event layers in sediment cores from Holocene Eifel maar lakes and Pleistocene dry maar structures. The cores were drilled in the Eifel region of western Germany. All maars have an inflow by a local stream and the largest flood events and associated suspension injections are nicely visible in the sediment. The specific sedimentation conditions explain the unique possibility to detect all 18 Greenland Interstadials in the total carbon concentration of the analysed maars. The allocation of the core material to all Greenland Interstadials and Stadials enables the exact climatic interpretation of the flood frequency. The stratigraphical concept leads to a classification of Landscape Evolution Zones in the Eifel region, which reconstruct the vegetation and the climate change (Sirocko et al., 2015). This classification is used to discuss the flood event succession concerning environmental changes. To study the past flood events in detail, 10 cm long thin sections were sedimentological and geochemical analysed to distinguish flood layers from turbidites and slumps. Turbidites have a continuous grain size gradation; the grains size profile of flood events is in contrast characterized by several grain size maxima over the entire layer thickness. A flood event over several days shows numerous peaks of intense discharge, which lead to a discontinuous grain size gradient. As a consequence, 233 flood layers over 7.5 mm thickness were detected. The main flood stages are from: 0 - 4000, 11 500 - 17 500, 23 000 - 24 000, 29 000 - 35 000 and 44 000 - 44 500 b2k (Brunck et al., 2015). Our time-series from the Eifel represents the first highly-resolved chronology for flood events from 60 000 years until present times and indicates variable periodicities of flood activity linked to predominant climatic and anthropogenic development. It turns out that low vegetation coverage related to Greenland Stadial phases or anthropogenic impact is the main cause for the development of flood layers in maar sediments, while precipitation plays only a secondary role. References Brunck, H., Albert, J., Sirocko, F., 2015 (in press). The ELSA - Flood - Stack: A reconstruction from the laminated sediments of Eifel Maar structures during the last 60 000 years. Global and Planetary Change, Elsevier. Sirocko, F., Knapp, H., Dreher, F., Förster, M., Albert, J., Brunck, H., Veres, D., Dietrich, S., Zech, M., Hambach, U., Röhner, M., Rudert, S., Schwibus, K., Adams, C., Sigl, P., 2015 (in press). The ELSA-Vegetation-Stack: Reconstruction of Landscape Evolution Zones (LEZ) from laminated Eifel maar sediments of the last 60 000 years. Global and Planetary Change, Elsevier.
Sinkhole flooding in Murfreesboro, Rutherford County, Tennessee, 2001-02
Bradley, Michael W.; Hileman, Gregg Edward
2006-01-01
The U.S. Geological Survey, in cooperation with the City of Murfreesboro, Tennessee, conducted an investigation from January 2001 through April 2002 to delineate sinkholes and sinkhole watersheds in the Murfreesboro area and to characterize the hydrologic response of sinkholes to major rainfall events. Terrain analysis was used to define sinkholes and delineate the sinkhole drainage areas. Flooding in 78 sinkholes in three focus areas was identified and tracked using aerial photography following three major storms in February 2001, January 2002, and March 2002. The three focus areas are located to the east, north, and northwest of Murfreesboro and are underlain primarily by the Ridley Limestone with some outcrops of the underlying Pierce Limestone. The observed sinkhole flooding is controlled by water inflow, water outflow, and the degree of the hydraulic connection (connectivity) to a ground-water conduit system. The observed sinkholes in the focus areas are grouped into three categories based on the sinkhole morphology and the connectivity to the ground-water system as indicated by their response to flooding. The three types of sinkholes described for these focus areas are pan sinkholes with low connectivity, deep sinkholes with high connectivity, and deep sinkholes with low connectivity to the ground-water conduit system. Shallow, broad pan sinkholes flood as water inflow from a storm inundates the depression at land surface. Water overflow from one pan sinkhole can flow downgradient and become inflow to a sinkhole at a lower altitude. Land-surface modifications that direct more water into a pan sinkhole could increase peak-flood altitudes and extend flood durations. Land-surface modifications that increase the outflow by overland drainage could decrease the flood durations. Road construction or alterations that reduce flow within or between pan sinkholes could result in increased flood durations. Flood levels and durations in the deeper sinkholes observed in the three focus areas are primarily affected by the connectivity with the ground-water conduit system. Deep sinkholes with a relatively high connectivity to the ground-water system fill quickly after a storm, and drain rapidly after the storm ends, and water levels decline as much as 3 to 5 feet per day in the first 2 to 3 days after a major storm. These sinkholes store the initial floodwater and then rapidly transmit water to the ground-water conduit system (high outflow). Land-surface changes that direct more water into the sinkhole may increase the flood peaks, but may not have a substantial effect on the flood durations. Deep sinkholes that have low connectivity to the ground-water conduit system may have a delayed peak water level and may drain slowly, only about 2 to 3 feet in 10 days. Outflow from these sinkholes is limited or restricted by low connectivity to the ground-water conduit system. Land-surface alterations that increase the inflow to the sinkholes can result in high flood levels or increased flood durations.
NASA Astrophysics Data System (ADS)
Khanh Triet Nguyen, Van; Dung Nguyen, Viet; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko
2016-04-01
The Vietnamese Mekong Delta (VMD) plays an important role in food security and socio-economic development of the country. Being a low-lying coastal region, the VMD is particularly susceptible to both riverine and tidal floods, which provide, on (the) one hand, the basis for the rich agricultural production and the livelihood of the people, but on the other hand pose a considerable hazard depending on the severity of the floods. But despite of potentially hazardous flood, the area remain active as a rice granary due to its nutrient-rich soils and sediment input, and dense waterways, canals and the long standing experience of the population living with floods. In response to both farmers' requests and governmental plans, the construction of flood protection infrastructure in the delta progressed rapidly in the last twenty years, notably at areas prone to deep flooding, i.e. the Plain of Reeds (PoR) and Long Xuyen Quadrangle (LXQ). Triple rice cropping becomes possible in farmlands enclosed by "full-dykes", i.e. dykes strong and high enough to prevent flooding of the flood plains for most of the floods. In these protected flood plains rice can be grown even during the peak flood period (September to November). However, little is known about the possibly (and already alleged) negative impacts of this fully flood protection measure to downstream areas. This study aims at quantifying how the flood regime in the lower part of the VMD (e.g. Can Tho, My Thuan, …) has been changed in the last 2 recent "big flood" events of 2000 and 2011 due to the construction of the full-dyke system in the upper part. First, an evaluation of 35 years of daily water level data was performed in order to detect trends at key gauging stations: Kratie: upper boundary of the Delta, Tan Chau and Chau Doc: areas with full-dyke construction, Can Tho and My Thuan: downstream. Results from the Mann-Kendall (MK) test show a decreasing trend of the annual maximum water level at 3 stations Kratie, Tan Chau and Chau Doc. The MK test statistic results (Z) for these stations are -0.23, -1.39 and -0.84 respectively. In contrary, significant increasing trend (at α = 1%) of annual flood peak at Can Tho and My Thuan is calculated, with the Z value are 5.20 and 4.28. A Monte Carlo experiment by adding assumed observation errors of 5%, 10% and 15% results in similar trend for these stations. After the trend analysis, a set of scenarios are generated based on various hydrological boundaries, infrastructure developments and climate change scenarios. The scenarios are simulated with the quasi-2D hydrodynamic model for the Mekong Delta (Dung, 2011; Manh, 2014) in order to separate and quantify the impacts of flood protection measures to the flood regime in the lower part of the delta in a spatially explicit manner, with a special focus on the urban and economic centers Can Tho and My Thuan. Based on these scenarios the change in flood hazard caused by the infrastructure development that has to be expected is described and possible mitigation actions are proposed.
How do I know if I’ve improved my continental scale flood early warning system?
NASA Astrophysics Data System (ADS)
Cloke, Hannah L.; Pappenberger, Florian; Smith, Paul J.; Wetterhall, Fredrik
2017-04-01
Flood early warning systems mitigate damages and loss of life and are an economically efficient way of enhancing disaster resilience. The use of continental scale flood early warning systems is rapidly growing. The European Flood Awareness System (EFAS) is a pan-European flood early warning system forced by a multi-model ensemble of numerical weather predictions. Responses to scientific and technical changes can be complex in these computationally expensive continental scale systems, and improvements need to be tested by evaluating runs of the whole system. It is demonstrated here that forecast skill is not correlated with the value of warnings. In order to tell if the system has been improved an evaluation strategy is required that considers both forecast skill and warning value. The combination of a multi-forcing ensemble of EFAS flood forecasts is evaluated with a new skill-value strategy. The full multi-forcing ensemble is recommended for operational forecasting, but, there are spatial variations in the optimal forecast combination. Results indicate that optimizing forecasts based on value rather than skill alters the optimal forcing combination and the forecast performance. Also indicated is that model diversity and ensemble size are both important in achieving best overall performance. The use of several evaluation measures that consider both skill and value is strongly recommended when considering improvements to early warning systems.
Watson, Kara M.; Hoppe, Heidi L.
2013-01-01
Digital flood-inundation maps for a 4.1-mile reach of the Saddle River from 0.6 miles downstream from the New Jersey-New York State boundary in Upper Saddle River Borough to 0.2 miles downstream from the East Allendale Road bridge in Saddle River Borough, New Jersey, were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to select water levels (stages) at the USGS streamgage 01390450, Saddle River at Upper Saddle River, New Jersey. Current conditions for estimating near real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/nwis/uv?site_no=01390450. The National Weather Service (NWS) forecasts flood hydrographs at many places that are often collocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relations (in effect March 2013) at USGS streamgage 01390450, Saddle River at Upper Saddle River, New Jersey, and documented high-water marks from recent floods. The hydraulic model was then used to determine eight water-surface profiles for flood stages at 0.5-foot (ft) intervals referenced to the streamgage datum, North American Vertical Datum of 1988 (NAVD 88), and ranging from bankfull, 0.5 ft below NWS Action Stage, to the upper extent of the stage-discharge rating which is approximately 1 ft higher than the highest recorded water level at the streamgage. Action Stage is the stage which when reached by a rising stream the NWS or a partner needs to take some type of mitigation action in preparation for possible significant hydrologic activity. The simulated water-surface profiles were then combined with a geographic information system 3-meter (9.84 ft) digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps along with real-time streamflow data and information regarding current stage from USGS streamgages and forecasted stream stages from the NWS provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Flood-inundation maps for the Saddle River from Rochelle Park to Lodi, New Jersey, 2012
Hoppe, Heidi L.; Watson, Kara M.
2012-01-01
Digital flood-inundation maps for a 2.75-mile reach of the Saddle River from 0.2 mile upstream from the Interstate 80 bridge in Rochelle Park to 1.5 miles downstream from the U.S. Route 46 bridge in Lodi, New Jersey, were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Saddle River at Lodi, New Jersey (station 01391500). Current conditions for estimating near real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/nwis/uv?site_no=01391500. The National Weather Service (NWS) forecasts flood hydrographs at many places that are often collocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the Saddle River at Lodi, New Jersey streamgage and documented high-water marks from recent floods. The hydraulic model was then used to determine 11 water-surface profiles for flood stages at the Saddle River streamgage at 1-ft intervals referenced to the streamgage datum, North American Vertical Datum of 1988 (NAVD 88), and ranging from bankfull, 0.5 ft below NWS Action Stage, to the extent of the stage-discharge rating, which is approximately 1 ft higher than the highest recorded water level at the streamgage. Action Stage is the stage which when reached by a rising stream the NWS or a partner needs to take some type of mitigation action in preparation for possible significant hydrologic activity. The simulated water-surface profiles were then combined with a geographic information system 3-meter (9.84-ft) digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.
Ijaz, Muhammad; Abbas, Syed Nazar; Farooqi, Shahid Hussain; Aqib, Amjad Islam; Anwar, Ghulam Ali; Rehman, Abdul; Ali, Muhammad Muddassir; Mehmood, Khalid; Khan, Amjad
2018-01-01
The bovine leptospirosis is an economically important zoonotic disease of flood affected areas worldwide, but scarce information is available about its epidemiology in Pakistan. This is a first study on sero-epidemiology of bovine leptospirosis in Pakistan. The objectives of this study were to investigate the sero-prevalence and associated risk factors of bovine leptospirosis in flood affected zone of Punjab, Pakistan. A total of 385 serum samples were randomly collected from four tehsils of district Muzaffargarh, Pakistan. The serum samples were subjected to indirect ELISA for the detection of anti-leptospira antibodies. The overall sero-prevalence of leptospirosis was 30.39%. The prevalence was significantly higher (p<0.001) in cattle (56.25%) than buffaloes (4.66%). The key risk factors identified based on multivariable logistic regression were; confined system of rearing, flooded area, and lesser to graduate level of education as risk factors for leptospirosis. The values of hematological parameters varied significantly (p<0.05) for Hb, TEC and PCV while there was no significant (p>0.05) difference among TLC values among sero-positive and sero-negative animals. The serum biochemical profile revealed significant differences (p<0.05) in values of ALT, AST and creatinine among the sero-positive and negative animals. Hence, it can be concluded that leptospirosis is an emerging and neglected disease in flood affected zone of Pakistan, and the disease needs to be explored comprehensively in other parts of the country to sort out solid strategies for its control and eradication. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Paz-Alberto, Annie Melinda; Ramos, Gloria N.; Espiritu, Jo Adrianne; Mapanao, Kathrina M.; Lao, Ranilo B.
2017-09-01
The Philippines has a geographic and geological setting that make it prone to various hazards including weather and climate-related. It is usually strongly affected by monsoon and typhoon occurrences that cause floods due to torrential rains that causes great risks in man's life and properties, resulting in a significant national loss. Strategies for disaster prevention to protect human lives, properties and social infrastructure is therefore necessary. Different important parameters in disaster risk management such as earth observations, Light Detection and Ranging and Geographic Information System were integrated and utilized in this study. This study dealt with mapping and assessment of buildings that might possibly be exposed and vulnerable to flooding based on the simulated flood maps at different rainfall scenarios in Bucao River Basin. The assessment was done through GIS overlay analysis of the CLSU PHIL-LiDAR 1 Project outputs, the 3D building GIS database and flood hazard maps. Results of this study were series of maps with statistics at different rainfall scenarios. From 23,097 building features extracted, 10,118 buildings, 4,258 buildings and 7,433 buildings were the identified highest number of buildings exposed to flooding and a total of 2,427 buildings, 3,914 buildings and 7,204 buildings from the exposed were identified that had high vulnerabilities in terms of height at low, medium and high hazards of 100 year return period, respectively. Through these maps, it is easier to disseminate information that is more realistic to the residents about the hazardous areas and to help them act on warning and evacuating measures.
Wheatcroft, R.A.; Stevens, A.W.; Hunt, L.M.; Milligan, T.G.
2006-01-01
Event-response coring on the Po River prodelta (northern Adriatic Sea) coupled with shipboard digital X-radiography, resistivity profiling, and grain-size analyses permitted documentation of the initial distribution and physical properties of the October 2000 flood deposit. The digital X-radiography system comprises a constant-potential X-ray source and an amorphous silicon imager with an active area of 29??42 cm and 12-bit depth resolution. Objective image segmentation algorithms based on bulk density (brightness), layer contacts (edge detection) and small-scale texture (fabric) were used to identify the flood deposit. Results indicate that the deposit formed in water depths of 6-29 m immediately adjacent to the three main distributary mouths of the Po (Pila, Tolle and Gnocca/Goro). Maximal thickness was 36 cm at a 20-m site off the main mouth (Pila), but many other sites hadthicknesses >20 cm. The Po flood deposit has a complex internal stratigraphy, with multiple layers, a diverse suite of physical sedimentary structures (e.g., laminations, ripple cross bedding, lenticular bedding, soft-sediment deformation structures), and dramatic changes in grain size that imply rapid deposition and fluctuations in energy during emplacement. Based on the flood deposit volume and well-constrained measurements of deposit bulk density the mass of the flood deposit was estimated to be 16??109 kg, which is about two-thirds of the estimated suspended sediment load delivered by the river during the event. The locus of deposition, overall thickness, and stratigraphic complexity of the flood deposit can best be explained by the relatively long sediment throughput times of the Po River, whereby sediment is delivered to the ocean during a range of conditions (i.e., the storm responsible for the precipitation is long gone), the majority of which are reflective of the fair-weather condition. Sediment is therefore deposited proximal to the river mouths, where it can form thick, but stratigraphically complex deposits. In contrast, floods of small rivers such as the Eel (northern California) are coupled to storm conditions, which lead to high levels of sediment dispersion. ?? 2006 Elsevier Ltd. All rights reserved.
Floods and climate: emerging perspectives for flood risk assessment and management
NASA Astrophysics Data System (ADS)
Merz, B.; Aerts, J.; Arnbjerg-Nielsen, K.; Baldi, M.; Becker, A.; Bichet, A.; Blöschl, G.; Bouwer, L. M.; Brauer, A.; Cioffi, F.; Delgado, J. M.; Gocht, M.; Guzzetti, F.; Harrigan, S.; Hirschboeck, K.; Kilsby, C.; Kron, W.; Kwon, H.-H.; Lall, U.; Merz, R.; Nissen, K.; Salvatti, P.; Swierczynski, T.; Ulbrich, U.; Viglione, A.; Ward, P. J.; Weiler, M.; Wilhelm, B.; Nied, M.
2014-07-01
Flood estimation and flood management have traditionally been the domain of hydrologists, water resources engineers and statisticians, and disciplinary approaches abound. Dominant views have been shaped; one example is the catchment perspective: floods are formed and influenced by the interaction of local, catchment-specific characteristics, such as meteorology, topography and geology. These traditional views have been beneficial, but they have a narrow framing. In this paper we contrast traditional views with broader perspectives that are emerging from an improved understanding of the climatic context of floods. We come to the following conclusions: (1) extending the traditional system boundaries (local catchment, recent decades, hydrological/hydraulic processes) opens up exciting possibilities for better understanding and improved tools for flood risk assessment and management. (2) Statistical approaches in flood estimation need to be complemented by the search for the causal mechanisms and dominant processes in the atmosphere, catchment and river system that leave their fingerprints on flood characteristics. (3) Natural climate variability leads to time-varying flood characteristics, and this variation may be partially quantifiable and predictable, with the perspective of dynamic, climate-informed flood risk management. (4) Efforts are needed to fully account for factors that contribute to changes in all three risk components (hazard, exposure, vulnerability) and to better understand the interactions between society and floods. (5) Given the global scale and societal importance, we call for the organization of an international multidisciplinary collaboration and data-sharing initiative to further understand the links between climate and flooding and to advance flood research.
NASA Astrophysics Data System (ADS)
Demir, I.; Krajewski, W. F.
2014-12-01
Recent advances in internet and cyberinfrastucture technologies have provided the capability to understand the hydrological and meteorological systems at space and time scales that are critical for making accurate understanding and prediction of flooding, and emergency preparedness. A novel example of a cyberinfrastructure platform for flood preparedness and response is the Iowa Flood Center's Iowa Flood Information System (IFIS). IFIS is a one-stop web-platform to access community-based flood conditions, forecasts, visualizations, inundation maps and flood-related data, information, and applications. An enormous volume of real-time observational data from a variety of sensors and remote sensing resources (radars, rain gauges, stream sensors, etc.) and complex flood inundation models are staged on a user-friendly maps environment that is accessible to the general public. IFIS has developed into a very successful tool used by agencies, decision-makers, and the general public throughout Iowa to better understand their local watershed and their personal and community flood risk, and to monitor local stream and river levels. IFIS helps communities make better-informed decisions on the occurrence of floods, and alerts communities in advance to help minimize flood damages. IFIS is widely used by general public in Iowa and the Midwest region with over 120,000 unique users, and became main source of information for many newspapers and TV stations in Iowa. IFIS has features for general public to improve emergency preparedness, and for decision makers to support emergency response and recovery efforts. IFIS is also a great platform for educators and local authorities to educate students and public on flooding with games, easy to use interactive environment, and data rich system.
Hydrologic and hydraulic flood forecasting constrained by remote sensing data
NASA Astrophysics Data System (ADS)
Li, Y.; Grimaldi, S.; Pauwels, V. R. N.; Walker, J. P.; Wright, A. J.
2017-12-01
Flooding is one of the most destructive natural disasters, resulting in many deaths and billions of dollars of damages each year. An indispensable tool to mitigate the effect of floods is to provide accurate and timely forecasts. An operational flood forecasting system typically consists of a hydrologic model, converting rainfall data into flood volumes entering the river system, and a hydraulic model, converting these flood volumes into water levels and flood extents. Such a system is prone to various sources of uncertainties from the initial conditions, meteorological forcing, topographic data, model parameters and model structure. To reduce those uncertainties, current forecasting systems are typically calibrated and/or updated using ground-based streamflow measurements, and such applications are limited to well-gauged areas. The recent increasing availability of spatially distributed remote sensing (RS) data offers new opportunities to improve flood forecasting skill. Based on an Australian case study, this presentation will discuss the use of 1) RS soil moisture to constrain a hydrologic model, and 2) RS flood extent and level to constrain a hydraulic model.The GRKAL hydrological model is calibrated through a joint calibration scheme using both ground-based streamflow and RS soil moisture observations. A lag-aware data assimilation approach is tested through a set of synthetic experiments to integrate RS soil moisture to constrain the streamflow forecasting in real-time.The hydraulic model is LISFLOOD-FP which solves the 2-dimensional inertial approximation of the Shallow Water Equations. Gauged water level time series and RS-derived flood extent and levels are used to apply a multi-objective calibration protocol. The effectiveness with which each data source or combination of data sources constrained the parameter space will be discussed.
NASA Technical Reports Server (NTRS)
Moore, Jeffrey M.; Clow, Gary D.; Davis, Wanda L.; Gulick, Virginia C.; Janke, David R.; Mckay, Christopher P.; Stoker, Carol R.; Zent, Aaron P.
1995-01-01
The transection and superposition relationships among channels, chaos, surface materials units, and other features in the circum-Chryse region of Mars were used to evaluate relative age relationships and evolution of flood events. Channels and chaos in contact (with one another) were treated as single discrete flood-carved systems. Some outflow channel systems form networks and are inferred to have been created by multiple flood events. Within some outflow channel networks, several separate individual channel systems can be traced to a specific chaos which acted as flood-source area to that specific flood channel. Individual flood-carved systems were related to widespread materials units or other surface features that served as stratigraphic horizons. Chryse outflow channels are inferred to have formed over most of the perceivable history of Mars. Outflow channels are inferred to become younger with increasing proximity to the Chryse basin. The relationship of subsequent outflow channel sources to the sources of earlier floods is inferred to disfavor episodic flooding due to the progresssive tapping of a juvenile near-surface water supply. Instead, we propose the circum-Chryse region as a candidate site of past hydrological recycling. The discharge rates necessary to carve the circum-Chryse outflow channels would have inevitably formed temporary standing bodies of H2O on the Martian surface where the flood-waters stagnated and pooled (the Chryse basin is topographically enclosed). These observations and inferences have led us to formulate and evaluate two hypotheses. Our numerical evaluations indicate that of these two hypotheses formulated, the groundwater seep cycle seems by far the more viable. Further observations from forthcoming missions may permit the determination of which mechanisms may have operated to recycle the Chryse flood-waters.
Target discrimination strategies in optics detection
NASA Astrophysics Data System (ADS)
Sjöqvist, Lars; Allard, Lars; Henriksson, Markus; Jonsson, Per; Pettersson, Magnus
2013-10-01
Detection and localisation of optical assemblies used for weapon guidance or sniper rifle scopes has attracted interest for security and military applications. Typically a laser system is used to interrogate a scene of interest and the retro-reflected radiation is detected. Different system approaches for area coverage can be realised ranging from flood illumination to step-and-stare or continuous scanning schemes. Independently of the chosen approach target discrimination is a crucial issue, particularly if a complex scene such as in an urban environment and autonomous operation is considered. In this work target discrimination strategies in optics detection are discussed. Typical parameters affecting the reflected laser radiation from the target are the wavelength, polarisation properties, temporal effects and the range resolution. Knowledge about the target characteristics is important to predict the target discrimination capability. Two different systems were used to investigate polarisation properties and range resolution information from targets including e.g. road signs, optical reflexes, rifle sights and optical references. The experimental results and implications on target discrimination will be discussed. If autonomous operation is required target discrimination becomes critical in order to reduce the number of false alarms.
Risk to life due to flooding in post-Katrina New Orleans
NASA Astrophysics Data System (ADS)
Miller, A.; Jonkman, S. N.; Van Ledden, M.
2015-01-01
Since the catastrophic flooding of New Orleans due to Hurricane Katrina in 2005, the city's hurricane protection system has been improved to provide protection against a hurricane load with a 1/100 per year exceedance frequency. This paper investigates the risk to life in post-Katrina New Orleans. In a flood risk analysis the probabilities and consequences of various flood scenarios have been analyzed for the central area of the city (the metro bowl) to give a preliminary estimate of the risk to life in the post-Katrina situation. A two-dimensional hydrodynamic model has been used to simulate flood characteristics of various breaches. The model for estimation of fatality rates is based on the loss of life data for Hurricane Katrina. Results indicate that - depending on the flood scenario - the estimated loss of life in case of flooding ranges from about 100 to nearly 500, with the highest life loss due to breaching of the river levees leading to large flood depths. The probability and consequence estimates are combined to determine the individual risk and societal risk for New Orleans. When compared to risks of other large-scale engineering systems (e.g., other flood prone areas, dams and the nuclear sector) and acceptable risk criteria found in literature, the risks for the metro bowl are found to be relatively high. Thus, despite major improvements to the flood protection system, the flood risk to life of post-Katrina New Orleans is still expected to be significant. Indicative effects of reduction strategies on the risk level are discussed as a basis for further evaluation and discussion.
In Search for Sustainable Coastal Management: A Case Study of Semarang, Indonesia
NASA Astrophysics Data System (ADS)
Hadi, Sudharto P.
2017-02-01
As a coastal town, Semarang is currently facing environmental problems such as flood, tidal flood (locally called rob), coastal abrasion, emerging land, land subsidence and sea water intrusion. These phenomena severely affect to citizen, community and corporate, disrupting day to day activities, threatening people’s health, causing economics’ burden and reducing property value. Government policies in dealing with these problem are focused on its phenomena such as normalizing river for flood and building polder systems for tidal flood. Impacted people have been implementing various initiatives. People in Tanah Mas Estate set up collective efforts to reduce tidal flood by building pumping system project, while people in Kampong Tambaklorok conduct a regular mutual assistance in cleaning of waste and sedimentation, rehabilitating of local drainages and dikes, reconstructing of local streets and also maintaining of pumping system. People in Mangunharjo, the district of Tugu build a coastal belt and cultivate mangrove. Various government and local initiatives have been effective in dealing with flood and tidal flood temporarily. More comprehensive approaches and focused on the sources of problems are required to achieve sustainable coastal management.
Flood forecasting within urban drainage systems using NARX neural network.
Abou Rjeily, Yves; Abbas, Oras; Sadek, Marwan; Shahrour, Isam; Hage Chehade, Fadi
2017-11-01
Urbanization activity and climate change increase the runoff volumes, and consequently the surcharge of the urban drainage systems (UDS). In addition, age and structural failures of these utilities limit their capacities, and thus generate hydraulic operation shortages, leading to flooding events. The large increase in floods within urban areas requires rapid actions from the UDS operators. The proactivity in taking the appropriate actions is a key element in applying efficient management and flood mitigation. Therefore, this work focuses on developing a flooding forecast system (FFS), able to alert in advance the UDS managers for possible flooding. For a forecasted storm event, a quick estimation of the water depth variation within critical manholes allows a reliable evaluation of the flood risk. The Nonlinear Auto Regressive with eXogenous inputs (NARX) neural network was chosen to develop the FFS as due to its calculation nature it is capable of relating water depth variation in manholes to rainfall intensities. The campus of the University of Lille is used as an experimental site to test and evaluate the FFS proposed in this paper.
NASA Astrophysics Data System (ADS)
Sörensen, Johanna; Emilsson, Tobias
2017-04-01
Sustainable Urban Drainage Systems (SUDS) has been put forward as a concept to improve stormwater management in urban areas. The damage reduction due to reduced flooding and storm water detention during extreme events is one of many important features of SUDS. As extreme events are rare, few assessments have earlier been made to evaluate the risk reduction. So far, most assessments have been done by hydraulic modelling, rather than analyses based on data from real flood events. In 2014, Malmö was hit with an extreme rainfall event which led to severe flooding in most parts of the city. This event gave an opportunity to evaluate the efficiency of SUDS during extreme events. In this study, flood claim data were analysed to evaluate flood risk reduction by the SUDS system in Augustenborg. Flood claim data were collected from both an insurance company, as well as the water utility company of Malmö for 5 neighbourhoods in close proximity in Malmö. The study uses the Augustenborg neighbourhood as an example of a retrofitted neighbourhood with an open SUDS. Augustenborg (Malmö, Sweden) was retrofitted 15 years ago using a combination of hard infrastructure and naturebased solutions, to alleviate basement flooding, to reduce combined sewer overflows (CSO) and to increase the ecological and aesthetical values of the area. The introduction of ponds, channels and green roofs dramatically changed the appearance of the area and the more or less regular floods were stopped. Augustenborg and its sustainable drainage system was compared with five similar neighbourhoods nearby. The long-term development of reported insurance claims in the selected neighbourhoods showed a reduction of flooding in Augustenborg compared to the nearby areas. Pre- and post-installation data showed a direct effect of the refurbishment with SUDS. Even though a few properties were flooded in Augustenborg, it was shown that the SUDS performed successfully during the extreme storm event that was the most severe flooding in Malmö in modern history. In conclusion, the SUDS in Augustenborg, Malmö, has been efficient in flood reduction during minor as well as severe flood events.
NASA Astrophysics Data System (ADS)
Perrou, Theodora; Papastergios, Asterios; Parcharidis, Issaak; Chini, Marco
2017-10-01
Flood disaster is one of the heaviest disasters in the world. It is necessary to monitor and evaluate the flood disaster in order to mitigate the consequences. As floods do not recognize borders, transboundary flood risk management is imperative in shared river basins. Disaster management is highly dependent on early information and requires data from the whole river basin. Based on the hypothesis that the flood events over the same area with same magnitude have almost identical evolution, it is crucial to develop a repository database of historical flood events. This tool, in the case of extended transboundary river basins, could constitute an operational warning system for the downstream area. The utility of SAR images for flood mapping, was demonstrated by previous studies but the SAR systems in orbit were not characterized by high operational capacity. Copernicus system will fill this gap in operational service for risk management, especially during emergency phase. The operational capabilities have been significantly improved by newly available satellite constellation, such as the Sentinel-1A AB mission, which is able to provide systematic acquisitions with a very high temporal resolution in a wide swath coverage. The present study deals with the monitoring of a transboundary flood event in Evros basin. The objective of the study is to create the "migration story" of the flooded areas on the basis of the evolution in time for the event occurred from October 2014 till May 2015. Flood hazard maps will be created, using SAR-based semi-automatic algorithms and then through the synthesis of the related maps in a GIS-system, a spatiotemporal thematic map of the event will be produced. The thematic map combined with TanDEM-X DEM, 12m/pixel spatial resolution, will define the non- affected areas which is a very useful information for the emergency planning and emergency response phases. The Sentinels meet the main requirements to be an effective and suitable operational tool in transboundary flood risk management.
Voice-enabled Knowledge Engine using Flood Ontology and Natural Language Processing
NASA Astrophysics Data System (ADS)
Sermet, M. Y.; Demir, I.; Krajewski, W. F.
2015-12-01
The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts, flood-related data, information and interactive visualizations for communities in Iowa. The IFIS is designed for use by general public, often people with no domain knowledge and limited general science background. To improve effective communication with such audience, we have introduced a voice-enabled knowledge engine on flood related issues in IFIS. Instead of navigating within many features and interfaces of the information system and web-based sources, the system provides dynamic computations based on a collection of built-in data, analysis, and methods. The IFIS Knowledge Engine connects to real-time stream gauges, in-house data sources, analysis and visualization tools to answer natural language questions. Our goal is the systematization of data and modeling results on flood related issues in Iowa, and to provide an interface for definitive answers to factual queries. The goal of the knowledge engine is to make all flood related knowledge in Iowa easily accessible to everyone, and support voice-enabled natural language input. We aim to integrate and curate all flood related data, implement analytical and visualization tools, and make it possible to compute answers from questions. The IFIS explicitly implements analytical methods and models, as algorithms, and curates all flood related data and resources so that all these resources are computable. The IFIS Knowledge Engine computes the answer by deriving it from its computational knowledge base. The knowledge engine processes the statement, access data warehouse, run complex database queries on the server-side and return outputs in various formats. This presentation provides an overview of IFIS Knowledge Engine, its unique information interface and functionality as an educational tool, and discusses the future plans for providing knowledge on flood related issues and resources. IFIS Knowledge Engine provides an alternative access method to these comprehensive set of tools and data resources available in IFIS. Current implementation of the system accepts free-form input and voice recognition capabilities within browser and mobile applications.
An Overview of the Iowa Flood Forecasting and Monitoring System
NASA Astrophysics Data System (ADS)
Krajewski, W. F.
2016-12-01
Following the 2008 flood that devastated eastern Iowa the state legislators established the Iowa Flood Center at the University of Iowa with the mission of translational research towards flood mitigation. The Center has adavanced several components towards this goal. In particular, the Center has developed (1) state-wide flood inundation maps based on airborne lidar-based topography data and hydraulic models; (2) a network of nearly 250 real-time ultrasonic river stage sensors; (3) a detailed rainfall-runoff model for real time streamflow forecasting; and (4) cyberinfrastructure to acquire and manage data that includes High Performance Computing and browser-based information system designed for use by general public. The author discusses these components, their operational performance and their potential to assist in development of similar nation-wide systems. Specifically, many developments taking place at the National Water Center can benefit from the Iowa system serving as a reference.
Walder, J.S.; Fountain, A.G.; ,
1997-01-01
Destructive floods result from drainage of glacier-dammed lakes and sudden release of water stored within glaciers. There is a good basis - both empirical and theoretical - for predicting the magnitude of floods from ice-dammed lakes, although some aspects of flood initiation need to be better understood. In contrast, an understanding of floods resulting from release of internally stored water remains elusive, owing to lack of knowledge of how and where water is stored and to inadequate understanding of the complex physics of the temporally and spatially variable subglacial drainage system.Destructive floods result from drainage of glacier-dammed lakes and sudden release of water stored within glaciers. There is a good basis - both empirical and theoretical - for predicting the magnitude of floods from ice-dammed lakes, although some aspects of flood initiation need to be better understood. In contrast, an understanding of floods resulting from release of internally stored water remains elusive, owing to lack of knowledge of how and where water is stored and to inadequate understanding of the complex physics of the temporally and spatially variable subglacial drainage system.
NASA Astrophysics Data System (ADS)
Schaefli, B.; Maraun, D.; Holschneider, M.
2007-12-01
Extreme hydrological events are often triggered by exceptional co-variations of the relevant hydrometeorological processes and in particular by exceptional co-oscillations at various temporal scales. Wavelet and cross wavelet spectral analysis offers promising time-scale resolved analysis methods to detect and analyze such exceptional co-oscillations. This paper presents the state-of-the-art methods of wavelet spectral analysis, discusses related subtleties, potential pitfalls and recently developed solutions to overcome them and shows how wavelet spectral analysis, if combined to a rigorous significance test, can lead to reliable new insights into hydrometeorological processes for real-world applications. The presented methods are applied to detect potentially flood triggering situations in a high Alpine catchment for which a recent re-estimation of design floods encountered significant problems simulating the observed high flows. For this case study, wavelet spectral analysis of precipitation, temperature and discharge offers a powerful tool to help detecting potentially flood producing meteorological situations and to distinguish between different types of floods with respect to the prevailing critical hydrometeorological conditions. This opens very new perspectives for the analysis of model performances focusing on the occurrence and non-occurrence of different types of high flow events. Based on the obtained results, the paper summarizes important recommendations for future applications of wavelet spectral analysis in hydrology.
Ranger, Christopher M.; Schultz, Peter B.; Reding, Michael E.; Frank, Steven D.; Palmquist, Debra E.
2016-01-01
Ambrosia beetles tunnel into the heartwood of trees where they cultivate and feed upon a symbiotic fungus. We assessed the effectiveness of flood stress for making Cercis canadensis L. and Cornus florida L. trees attractive to attack as part of insecticide and fungicide efficacy trials conducted in Ohio and Virginia. Since female ambrosia beetles will not begin ovipositing until their symbiotic fungus is established within the host, we also assessed pre-treatment of trees with permethrin, azoxystrobin, and potassium phosphite on fungal establishment and beetle colonization success. Permethrin reduced attacks on flooded trees, yet no attacks occurred on any of the non-flooded trees. Fewer galleries created within flooded trees pre-treated with permethrin, azoxystrobin, and potassium phosphite contained the purported symbiotic fungus; foundress’ eggs were only detected in flooded but untreated trees. While pre-treatment with permethrin, azoxystrobin, and potassium phosphite can disrupt colonization success, maintaining tree health continues to be the most effective and sustainable management strategy. PMID:27548230
Slovak Flood Forecasting Service at the National and International Level
NASA Astrophysics Data System (ADS)
Leskova, Danica; Mikuličková, Michaela
2017-04-01
National Flood Forecasting Service is based on national legislation /Slovak legislation/ so that it could deal with the flood situation at the local level. Information about international rivers, e.g.: Danube, March (Morava), Uh, and Latorica are received on the basis of bilateral agreements. An important supplementary information is the European Flood Awareness System (EFAS). In this presentation a forecasting system POVAPSYS, which has been in Slovakia in use since 2016, is also shown. The Slovak Hydrometeorological Institute (SHMI) is a partner of EFAS, but simultaneously is a part of consortium of the EFAS Dissemination Centre, and its role is to analyze results of models, to analyze hydrometeorological situation, to disseminate information, and to send flood notifications to the EFAS partners. Both systems will be presented.
NASA Astrophysics Data System (ADS)
Jeong, C.; Om, J.; Hwang, J.; Joo, K.; Heo, J.
2013-12-01
In recent, the frequency of extreme flood has been increasing due to climate change and global warming. Highly flood damages are mainly caused by the collapse of flood control structures such as dam and dike. In order to reduce these disasters, the disaster management system (DMS) through flood forecasting, inundation mapping, EAP (Emergency Action Plan) has been studied. The estimation of inundation damage and practical EAP are especially crucial to the DMS. However, it is difficult to predict inundation and take a proper action through DMS in real emergency situation because several techniques for inundation damage estimation are not integrated and EAP is supplied in the form of a document in Korea. In this study, the integrated simulation system including rainfall frequency analysis, rainfall-runoff modeling, inundation prediction, surface runoff analysis, and inland flood analysis was developed. Using this system coupled with standard GIS data, inundation damage can be estimated comprehensively and automatically. The standard EAP based on BIM (Building Information Modeling) was also established in this system. It is, therefore, expected that the inundation damages through this study over the entire area including buildings can be predicted and managed.
NASA Astrophysics Data System (ADS)
Nagai, H.; Ohki, M.; Abe, T.
2017-12-01
Urgent crisis response for a hurricane-induced flood needs urgent providing of a flood map covering a broad region. However, there is no standard threshold values for automatic flood identification from pre-and-post images obtained by satellite-based synthetic aperture radars (SARs). This problem could hamper prompt data providing for operational uses. Furthermore, one pre-flood SAR image does not always represent potential water surfaces and river flows especially in tropical flat lands which are greatly influenced by seasonal precipitation cycle. We are, therefore, developing a new method of flood mapping using PALSAR-2, an L-band SAR, which is less affected by temporal surface changes. Specifically, a mean-value image and a standard-deviation image are calculated from a series of pre-flood SAR images. It is combined with a post-flood SAR image to obtain normalized backscatter amplitude difference (NoBADi), with which a difference between a post-flood image and a mean-value image is divided by a standard-deviation image to emphasize anomalous water extents. Flooding areas are then automatically obtained from the NoBADi images as lower-value pixels avoiding potential water surfaces. We applied this method to PALSAR-2 images acquired on Sept. 8, 10, and 12, 2017, covering flooding areas in a central region of Dominican Republic and west Florida, the U.S. affected by Hurricane Irma. The output flooding outlines are validated with flooding areas manually delineated from high-resolution optical satellite images, resulting in higher consistency and less uncertainty than previous methods (i.e., a simple pre-and-post flood difference and pre-and-post coherence changes). The NoBADi method has a great potential to obtain a reliable flood map for future flood hazards, not hampered by cloud cover, seasonal surface changes, and "casual" thresholds in the flood identification process.
Shivers, Molly J.; Smith, S. Jerrod; Grout, Trevor S.; Lewis, Jason M.
2015-01-01
Digital-elevation models, field survey measurements, hydraulic data, and hydrologic data (U.S. Geological Survey streamflow-gaging stations North Canadian River below Lake Overholser near Oklahoma City, Okla. [07241000], and North Canadian River at Britton Road at Oklahoma City, Okla. [07241520]), were used as inputs for the one-dimensional dynamic (unsteady-flow) models using Hydrologic Engineering Centers River Analysis System (HEC–RAS) software. The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum flood dam-breach scenario and a sunny-day dam-breach scenario, as well as for maximum flood-inundation elevations and flood-wave arrival times at selected bridge crossings. Points of interest such as community-services offices, recreational areas, water-treatment plants, and wastewater-treatment plants were identified on the flood-inundation maps.
NASA Astrophysics Data System (ADS)
Schindewolf, Marcus; Kaiser, Andreas; Buchholtz, Arno; Schmidt, Jürgen
2017-04-01
Extreme rainfall events and resulting flash floods led to massive devastations in Germany during spring 2016. The study presented aims on the development of a early warning system, which allows the simulation and assessment of negative effects on infrastructure by radar-based heavy rainfall predictions, serving as input data for the process-based soil loss and deposition model EROSION 3D. Our approach enables a detailed identification of runoff and sediment fluxes in agricultural used landscapes. In a first step, documented historical events were analyzed concerning the accordance of measured radar rainfall and large scale erosion risk maps. A second step focused on a small scale erosion monitoring via UAV of source areas of heavy flooding events and a model reconstruction of the processes involved. In all examples damages were caused to local infrastructure. Both analyses are promising in order to detect runoff and sediment delivering areas even in a high temporal and spatial resolution. Results prove the important role of late-covering crops such as maize, sugar beet or potatoes in runoff generation. While e.g. winter wheat positively affects extensive runoff generation on undulating landscapes, massive soil loss and thus muddy flows are observed and depicted in model results. Future research aims on large scale model parameterization and application in real time, uncertainty estimation of precipitation forecast and interface developments.
A Bayesian-Based System to Assess Wave-Driven Flooding Hazards on Coral Reef-Lined Coasts
NASA Astrophysics Data System (ADS)
Pearson, S. G.; Storlazzi, C. D.; van Dongeren, A. R.; Tissier, M. F. S.; Reniers, A. J. H. M.
2017-12-01
Many low-elevation, coral reef-lined, tropical coasts are vulnerable to the effects of climate change, sea level rise, and wave-induced flooding. The considerable morphological diversity of these coasts and the variability of the hydrodynamic forcing that they are exposed to make predicting wave-induced flooding a challenge. A process-based wave-resolving hydrodynamic model (XBeach Non-Hydrostatic, "XBNH") was used to create a large synthetic database for use in a "Bayesian Estimator for Wave Attack in Reef Environments" (BEWARE), relating incident hydrodynamics and coral reef geomorphology to coastal flooding hazards on reef-lined coasts. Building on previous work, BEWARE improves system understanding of reef hydrodynamics by examining the intrinsic reef and extrinsic forcing factors controlling runup and flooding on reef-lined coasts. The Bayesian estimator has high predictive skill for the XBNH model outputs that are flooding indicators, and was validated for a number of available field cases. It was found that, in order to accurately predict flooding hazards, water depth over the reef flat, incident wave conditions, and reef flat width are the most essential factors, whereas other factors such as beach slope and bed friction due to the presence or absence of corals are less important. BEWARE is a potentially powerful tool for use in early warning systems or risk assessment studies, and can be used to make projections about how wave-induced flooding on coral reef-lined coasts may change due to climate change.
NASA Astrophysics Data System (ADS)
Pandeya, B.; Uprety, M.; Paul, J. D.; Dugar, S.; Buytaert, W.
2017-12-01
With a robust and affordable monitoring system, a wealth of hydrological data can be generated which is fundamental to predict flood risks more accurately. Since the Himalayan region is characterized by data deficiency and unpredictable hydrological behaviour, a locally based participatory monitoring system is a necessity to deal with frequently occurring flooding incidents. A gap in hydrological data is the main bottleneck for establishing any effective flood early warning system. Therefore, an alternative and affordable technical solution can only overcome the situation and support flood risks management activities in the region. In coordination with local people, government authorities and NGOs, we have established a citizen science monitoring system, in which we tested two types of low-cost sensors, ultrasound and LiDAR, in the Karnali river basin of Nepal. The results confirm the robustness of sensor data when compared to conventional radar system based monitoring data. Additionally, our findings also confirmed that the ultrasound sensors are only useful to small rivers whereas the LiDAR sensors are suitable to large river basins with highly variable local climatic conditions. Since the collected sensor data can be directly used in operational flood early warning system in the basin, an opportunity has been created for integrating both affordable technology and citizen science into existing hydrological monitoring practice. Finally, a successful integration could become a testament for upscaling the practice and building flood risk resilient communities in the region.
NASA Astrophysics Data System (ADS)
Hartmann, A. J.; Ireson, A. M.
2017-12-01
Chalk aquifers represent an important source of drinking water in the UK. Due to its fractured-porous structure, Chalk aquifers are characterized by highly dynamic groundwater fluctuations that enhance the risk of groundwater flooding. The risk of groundwater flooding can be assessed by physically-based groundwater models. But for reliable results, a-priori information about the distribution of hydraulic conductivities and porosities is necessary, which is often not available. For that reason, conceptual simulation models are often used to predict groundwater behaviour. They commonly require calibration by historic groundwater observations. Consequently, their prediction performance may reduce significantly, when it comes to system states that did not occur within the calibration time series. In this study, we calibrate a conceptual model to the observed groundwater level observations at several locations within a Chalk system in Southern England. During the calibration period, no groundwater flooding occurred. We then apply our model to predict the groundwater dynamics of the system at a time that includes a groundwater flooding event. We show that the calibrated model provides reasonable predictions before and after the flooding event but it over-estimates groundwater levels during the event. After modifying the model structure to include topographic information, the model is capable of prediction the groundwater flooding event even though groundwater flooding never occurred in the calibration period. Although straight forward, our approach shows how conceptual process-based models can be applied to predict system states and dynamics that did not occur in the calibration period. We believe such an approach can be transferred to similar cases, especially to regions where rainfall intensities are expected to trigger processes and system states that may have not yet been observed.
A real-time measurement system for long-life flood monitoring and warning applications.
Marin-Perez, Rafael; García-Pintado, Javier; Gómez, Antonio Skarmeta
2012-01-01
A flood warning system incorporates telemetered rainfall and flow/water level data measured at various locations in the catchment area. Real-time accurate data collection is required for this use, and sensor networks improve the system capabilities. However, existing sensor nodes struggle to satisfy the hydrological requirements in terms of autonomy, sensor hardware compatibility, reliability and long-range communication. We describe the design and development of a real-time measurement system for flood monitoring, and its deployment in a flash-flood prone 650 km(2) semiarid watershed in Southern Spain. A developed low-power and long-range communication device, so-called DatalogV1, provides automatic data gathering and reliable transmission. DatalogV1 incorporates self-monitoring for adapting measurement schedules for consumption management and to capture events of interest. Two tests are used to assess the success of the development. The results show an autonomous and robust monitoring system for long-term collection of water level data in many sparse locations during flood events.
A Real-Time Measurement System for Long-Life Flood Monitoring and Warning Applications
Marin-Perez, Rafael; García-Pintado, Javier; Gómez, Antonio Skarmeta
2012-01-01
A flood warning system incorporates telemetered rainfall and flow/water level data measured at various locations in the catchment area. Real-time accurate data collection is required for this use, and sensor networks improve the system capabilities. However, existing sensor nodes struggle to satisfy the hydrological requirements in terms of autonomy, sensor hardware compatibility, reliability and long-range communication. We describe the design and development of a real-time measurement system for flood monitoring, and its deployment in a flash-flood prone 650 km2 semiarid watershed in Southern Spain. A developed low-power and long-range communication device, so-called DatalogV1, provides automatic data gathering and reliable transmission. DatalogV1 incorporates self-monitoring for adapting measurement schedules for consumption management and to capture events of interest. Two tests are used to assess the success of the development. The results show an autonomous and robust monitoring system for long-term collection of water level data in many sparse locations during flood events. PMID:22666028
NASA Astrophysics Data System (ADS)
Guo, Aijun; Chang, Jianxia; Wang, Yimin; Huang, Qiang; Zhou, Shuai
2018-05-01
Traditional flood risk analysis focuses on the probability of flood events exceeding the design flood of downstream hydraulic structures while neglecting the influence of sedimentation in river channels on regional flood control systems. This work advances traditional flood risk analysis by proposing a univariate and copula-based bivariate hydrological risk framework which incorporates both flood control and sediment transport. In developing the framework, the conditional probabilities of different flood events under various extreme precipitation scenarios are estimated by exploiting the copula-based model. Moreover, a Monte Carlo-based algorithm is designed to quantify the sampling uncertainty associated with univariate and bivariate hydrological risk analyses. Two catchments located on the Loess plateau are selected as study regions: the upper catchments of the Xianyang and Huaxian stations (denoted as UCX and UCH, respectively). The univariate and bivariate return periods, risk and reliability in the context of uncertainty for the purposes of flood control and sediment transport are assessed for the study regions. The results indicate that sedimentation triggers higher risks of damaging the safety of local flood control systems compared with the event that AMF exceeds the design flood of downstream hydraulic structures in the UCX and UCH. Moreover, there is considerable sampling uncertainty affecting the univariate and bivariate hydrologic risk evaluation, which greatly challenges measures of future flood mitigation. In addition, results also confirm that the developed framework can estimate conditional probabilities associated with different flood events under various extreme precipitation scenarios aiming for flood control and sediment transport. The proposed hydrological risk framework offers a promising technical reference for flood risk analysis in sandy regions worldwide.
NASA Astrophysics Data System (ADS)
Zhou, Zhengzheng; Smith, James A.; Yang, Long; Baeck, Mary Lynn; Chaney, Molly; Ten Veldhuis, Marie-Claire; Deng, Huiping; Liu, Shuguang
2017-08-01
We examine urban flood response through data-driven analyses for a diverse sample of "small" watersheds (basin scale ranging from 7.0 to 111.1 km2) in the Charlotte Metropolitan region. These watersheds have experienced extensive urbanization and suburban development since the 1960s. The objective of this study is to develop a broad characterization of land surface and hydrometeorological controls of urban flood hydrology. Our analyses are based on peaks-over-threshold flood data developed from USGS streamflow observations and are motivated by problems of flood hazard characterization for urban regions. We examine flood-producing rainfall using high-resolution (1 km2 spatial resolution and 15 min time resolution), bias-corrected radar rainfall fields that are developed through the Hydro-NEXRAD system. The analyses focus on the 2001-2015 period. The results highlight the complexities of urban flood response. There are striking spatial heterogeneities in flood peak magnitudes, response times, and runoff ratios across the study region. These spatial heterogeneities are mainly linked to watershed scale, the distribution of impervious cover, and storm water management. Contrasting land surface properties also determine the mixture of flood-generating mechanisms for a particular watershed. Warm-season thunderstorm systems and tropical cyclones are main flood agents in Charlotte, with winter/spring storms playing a role in less-urbanized watersheds. The mixture of flood agents exerts a strong impact on the upper tail of flood frequency distributions. Antecedent watershed wetness plays a minor role in urban flood response, compared with less-urbanized watersheds. Implications for flood hazard characterization in urban watersheds and for advances in flood science are discussed.
The impact of bathymetry input on flood simulations
NASA Astrophysics Data System (ADS)
Khanam, M.; Cohen, S.
2017-12-01
Flood prediction and mitigation systems are inevitable for improving public safety and community resilience all over the worldwide. Hydraulic simulations of flood events are becoming an increasingly efficient tool for studying and predicting flood events and susceptibility. A consistent limitation of hydraulic simulations of riverine dynamics is the lack of information about river bathymetry as most terrain data record water surface elevation. The impact of this limitation on the accuracy on hydraulic simulations of flood has not been well studies over a large range of flood magnitude and modeling frameworks. Advancing our understanding of this topic is timely given emerging national and global efforts for developing automated flood predictions systems (e.g. NOAA National Water Center). Here we study the response of flood simulation to the incorporation of different bathymetry and floodplain surveillance source. Different hydraulic models are compared, Mike-Flood, a 2D hydrodynamic model, and GSSHA, a hydrology/hydraulics model. We test a hypothesis that the impact of inclusion/exclusion of bathymetry data on hydraulic model results will vary in its magnitude as a function of river size. This will allow researcher and stake holders more accurate predictions of flood events providing useful information that will help local communities in a vulnerable flood zone to mitigate flood hazards. Also, it will help to evaluate the accuracy and efficiency of different modeling frameworks and gage their dependency on detailed bathymetry input data.
Flood inundation mapping in the Logone floodplain from multi temporal Landsat ETM+ imagery
NASA Astrophysics Data System (ADS)
Jung, H.; Alsdorf, D. E.; Moritz, M.; Lee, H.; Vassolo, S.
2011-12-01
Yearly flooding in the Logone floodplain makes an impact on agricultural, pastoral, and fishery systems in the Lake Chad Basin. Since the flooding extent and depth are highly variable, flood inundation mapping helps us make better use of water resources and prevent flood hazards in the Logone floodplain. The flood maps are generated from 33 multi temporal Landsat Enhanced Thematic Mapper Plus (ETM+) during three years 2006 to 2008. Flooded area is classified using a short-wave infrared band whereas open water is classified by Iterative Self-organizing Data Analysis (ISODATA) clustering. The maximum flooding extent in the study area increases up to ~5.8K km2 in late October 2008. The study also provides strong correlation of the flooding extents with water height variations in both the floodplain and the river based on a second polynomial regression model. The water heights are from ENIVSAT altimetry in the floodplain and gauge measurements in the river. Coefficients of determination between flooding extents and water height variations are greater than 0.91 with 4 to 36 days in phase lag. Floodwater drains back to the river and to the northeast during the recession period in December and January. The study supports understanding of the Logone floodplain dynamics in detail of spatial pattern and size of the flooding extent and assists the flood monitoring and prediction systems in the catchment.
Flood Inundation Mapping in the Logone Floodplain from Multi Temporal Landsat ETM+Imagery
NASA Technical Reports Server (NTRS)
Jung, Hahn Chul; Alsdorf, Douglas E.; Moritz, Mark; Lee, Hyongki; Vassolo, Sara
2011-01-01
Yearly flooding in the Logone floodplain makes an impact on agricultural, pastoral, and fishery systems in the Lake Chad Basin. Since the flooding extent and depth are highly variable, flood inundation mapping helps us make better use of water resources and prevent flood hazards in the Logone floodplain. The flood maps are generated from 33 multi temporal Landsat Enhanced Thematic Mapper Plus (ETM+) during three years 2006 to 2008. Flooded area is classified using a short-wave infrared band whereas open water is classified by Iterative Self-organizing Data Analysis (ISODATA) clustering. The maximum flooding extent in the study area increases up to approximately 5.8K km2 in late October 2008. The study also provides strong correlation of the flooding extents with water height variations in both the floodplain and the river based on a second polynomial regression model. The water heights are from ENIVSAT altimetry in the floodplain and gauge measurements in the river. Coefficients of determination between flooding extents and water height variations are greater than 0.91 with 4 to 36 days in phase lag. Floodwater drains back to the river and to the northeast during the recession period in December and January. The study supports understanding of the Logone floodplain dynamics in detail of spatial pattern and size of the flooding extent and assists the flood monitoring and prediction systems in the catchment.
NASA Astrophysics Data System (ADS)
Albano, R.; Sole, A.; Adamowski, J.
2015-02-01
As evidenced by the EU Floods Directive (2007/60/EC), flood management strategies in Europe have undergone a shift in focus in recent years. The goal of flood prevention using structural measures has been replaced by an emphasis on the management of flood risks using non-structural measures. One implication of this is that it is no longer public authorities alone who take responsibility for flood management. A broader range of stakeholders, who may experience the negative effects of flooding, also take on responsibility to protect themselves. Therefore, it is vital that information concerning flood risks are conveyed to those who may be affected in order to facilitate the self-protection of citizens. Experience shows that even where efforts have been made to communicate flood risks, problems persist. There is a need for the development of new tools, which are able to rapidly disseminate flood risk information to the general public. To be useful, these tools must be able to present information relevant to the location of the user. Moreover, the content and design of the tool need to be adjusted to laypeople's needs. Dissemination and communication influences both people's access to and understanding of natural risk information. Such a tool could be a useful aid to effective management of flood risks. To address this gap, a Web-based Geographical Information System, (WebGIS), has been developed through the collaborative efforts of a group of scientists, hazard and risk analysts and managers, GIS analysts, system developers and communication designers. This tool, called "READY: Risk, Extreme Events, Adaptation, Defend Yourself", aims to enhance the general public knowledge of flood risk, making them more capable of responding appropriately during a flood event. The READY WebGIS has allowed for the visualization and easy querying of a complex hazard and risk database thanks to a high degree of interactivity and its easily readable maps. In this way, READY has enabled fast exploration of alternative flood scenarios or past calamitous events. Combined also with a system of graphic symbols designed ad hoc for communication of self-protection behaviors, it is believed READY could lead to an increase in citizen participation, informed discussion and consensus building. The platform has been developed for a site-specific application, i.e. the Basilicata Region, Italy, has been selected as pilot application area. The goal of the prototype is to raise citizen awareness of flood risks, and to build social capacity and enhanced resilience to flood events.
NASA Astrophysics Data System (ADS)
Albano, R.; Sole, A.; Adamowski, J.
2015-07-01
As evidenced by the EU Floods Directive (2007/60/EC), flood management strategies in Europe have undergone a shift in focus in recent years. The goal of flood prevention using structural measures has been replaced by an emphasis on the management of flood risks using non-structural measures. One implication of this is that public authorities alone not only take responsibility for flood management. A broader range of stakeholders, who may personally experience the negative effects of flooding, also take on responsibility for protecting themselves. Therefore, it is vital that information concerning flood risks is conveyed to those who may be affected in order to facilitate the self-protection of citizens. Experience shows that problems persist even where efforts have been made to communicate flood risks. There is a need for the development of new tools that are able to rapidly disseminate flood-risk information to the general public. To be useful these tools must be able to present information relevant to the location of the user. Moreover, the content and design of the tool need to be adjusted to laypeople's needs. Dissemination and communication influence both people's access to and understanding of natural risk information. Such a tool could be a useful aid to effective management of flood risks. To address this gap, a web-based geographical information system (WebGIS) has been developed through the collaborative efforts of a group of scientists, hazard and risk analysts and managers, GIS analysts, system developers and communication designers. This tool, called "READY: Risk, Extreme Events, Adaptation, Defend Yourself", aims to enhance the general public knowledge of flood risk, making citizens more capable of responding appropriately during a flood event. The READY WebGIS has allowed for the visualization and easy querying of a complex hazard and risk database thanks to a high degree of interactivity and easily read maps. In this way, READY has enabled fast exploration of alternative flood scenarios or past calamitous events. Combined also with a system of graphic symbols designed ad hoc for communication of self-protection behaviours, it is believed READY could lead to an increase in citizen participation, informed discussion and consensus building. The platform has been developed for a site-specific application: the Basilicata region, Italy, has been selected as pilot application area. The goal of the prototype is to raise citizen awareness of flood risks and to build social capacity and enhanced resilience to flood events.
Developing a flood monitoring system from remotely sensed data for the Limpopo basin
Asante, K.O.; Macuacua, R.D.; Artan, G.A.; Lietzow, R.W.; Verdin, J.P.
2007-01-01
This paper describes the application of remotely sensed precipitation to the monitoring of floods in a region that regularly experiences extreme precipitation and flood events, often associated with cyclonic systems. Precipitation data, which are derived from spaceborne radar aboard the National Aeronautics and Space Administration's Tropical Rainfall Measuring Mission and from National Oceanic and Atmospheric Administration's infrared-based products, are used to monitor areas experiencing extreme precipitation events that are defined as exceedance of a daily mean areal average value of 50 mm over a catchment. The remotely sensed precipitation data are also ingested into a hydrologic model that is parameterized using spatially distributed elevation, soil, and land cover data sets that are available globally from remote sensing and in situ sources. The resulting stream-flow is classified as an extreme flood event when flow anomalies exceed 1.5 standard deviations above the short-term mean. In an application in the Limpopo basin, it is demonstrated that the use of satellite-derived precipitation allows for the identification of extreme precipitation and flood events, both in terms of relative intensity and spatial extent. The system is used by water authorities in Mozambique to proactively initiate independent flood hazard verification before generating flood warnings. The system also serves as a supplementary information source when in situ gauging systems are disrupted. This paper concludes that remotely sensed precipitation and derived products greatly enhance the ability of water managers in the Limpopo basin to monitor extreme flood events and provide at-risk communities with early warning information. ?? 2007 IEEE.
A Collaborative Approach to Flood Early Warning Systems In South East Westmoreland, Jamaica
NASA Astrophysics Data System (ADS)
Hyman, T. A.
2015-12-01
Jamaica is prone to climatic, tectonic and technological hazards, with climatic hazards being the most prevalent. Specifically, flood events from cyclonic activity are the most common and widespread. Jamaica also experiences frequent flash floods, usually with insufficient lead time to enact efficient and targeted responses. On average, there is at least one disastrous flood every four years in Jamaica, and from 1800 to 2003 fifty-four major floods took place, causing 273 fatalities and economic losses of over US2 billion. Notably, the 1979 flood event in Western Jamaica caused 41 deaths and economic losses of US 27 Million, and which also has a 50 year return period. To date, no Flood Warning System exists in Western Jamaica and there are limited rain and river gauges. Additionally, responses to climatic events within South-East Westmoreland communities are ad hoc, with little coordination. Many of the hazard responses have been reactive and some stakeholders have delayed to their detriment.[1] The use of Flood Early Warning Systems (FEWS) to address such challenges is thus an option being considered by the community associations. The Rio Cobre FEWS in the parish of St. Catherine serves as a best practice example of community driven flood warning systems in Jamaica. This is because of the collaborative approach to flood risk, strengthened by institutional arrangements between the Meteorological Service, Water Resources Authority, Office of Disaster Management, Scientists and residents of the surrounding communities. The Community Associations in South-East Westmoreland are thus desirous of implementing a FEWS similar to the Rio Cobre FEWS. This paper thus aims to analyse the implementation process in terms of key stakeholders involved, governance approach and the socio-economic impact of a collaborative approach on infrastructure and livelihoods, in the case of future flooding events. [1] (especially in the case of Hurricane Ivan 2004)
A methodology for urban flood resilience assessment
NASA Astrophysics Data System (ADS)
Lhomme, Serge; Serre, Damien; Diab, Youssef; Laganier, Richard
2010-05-01
In Europe, river floods have been increasing in frequency and severity [Szöllösi-Nagy and Zevenbergen, 2005]. Moreover, climate change is expected to exacerbate the frequency and intensity of hydro meteorological disaster [IPCC, 2007]. Despite efforts made to maintain the flood defense assets, we often observe levee failures leading to finally increase flood risk in protected area. Furthermore, flood forecasting models, although benefiting continuous improvements, remain partly inaccurate due to uncertainties arising all along data calculation processes. In the same time, the year 2007 marks a turning point in history: half of the world population now lives in cities (UN-Habitat, 2007). Moreover, the total urban population is expected to double from two to four billion over the next 30 to 35 years (United Nations, 2006). This growing rate is equivalent to the creation of a new city of one million inhabitants every week, and this during the next four decades [Flood resilience Group]. So, this quick urban development coupled with technical failures and climate change have increased flood risk and corresponding challenges to urban flood risk management [Ashley et al., 2007], [Nie et al., 2009]. These circumstances oblige to manage flood risk by integrating new concepts like urban resilience. In recent years, resilience has become a central concept for risk management. This concept has emerged because a more resilient system is less vulnerable to risk and, therefore, more sustainable [Serre et al., 2010]. But urban flood resilience is a concept that has not yet been directly assessed. Therefore, when decision makers decide to use the resilience concept to manage urban flood, they have no tool to help them. That is why this paper proposes a methodology to assess urban flood resilience in order to make this concept operational. Networks affect the well-being of the people and the smooth functioning of services and, more generally, of economical activities. Yet, multiple networks that innervate the city are particularly sensitive to flooding, through their structures and geographic constraints. Because societal functions are highly dependent on networked systems and the operability of these systems can be vulnerable to disasters, there is a need to understand how networked systems are resilient. That is why, considering that networks can be regarded as the "flood gateway" [Lhomme et al., 2009], we will focus on the resilience assessment of these critical networks before urban resilience assessment. The first part of this paper introduce resilience concept to well understand the importance of this concept to manage flood risk and of assessing this resilience. In a second part, this paper presents the use of safety methods to model network system dysfunctions during flood and then to produce resilience indicators. Finally it presents use of graph theory to assess adaptive capacity of these networks. These researches are the first steps toward the development of a GIS tool to optimize preparedness and recovery after a flood event.
Virus movement in soil columns flooded with secondary sewage effluent.
Lance, J C; Gerba, C P; Melnick, J L
1976-01-01
Secondary sewage effluent containing about 3 X 10(4) plaque-forming units of polio virus type 1 (LSc) per ml was passed through columns 250 cm in length packed with calcareous sand from an area in the Salt River bed used for ground-water recharge of secondary sewage effluent. Viruses were not detected in 1-ml samples extracted from the columns below the 160-cm level. However, viruses were detected in 5 of 43 100-ml samples of the column drainage water. Most of the viruses were adsorbed in the top 5 cm of soil. Virus removal was not affected by the infiltration rate, which varied between 15 and 55 cm/day. Flooding a column continuosly for 27 days with the sewage water virus mixture did not saturate the top few centimeters of soil with viruses and did not seem to affect virus movement. Flooding with deionized water caused virus desorption from the soil and increased their movement through the columns. Adding CaCl2 to the deionized water prevented most of the virus desorption. Adding a pulse of deionized water followed by sewage water started a virus front moving through the columns, but the viruses were readsorbed and none was detected in outflow samples. Drying the soil for 1 day between applying the virus and flooding with deionized water greatly reduced desorption, and drying for 5 days prevented desorption. Large reductions (99.99% or more) of virus would be expected after passage of secondary sewage effluent through 250 cm of the calcareous sand similar to that used in our laboratory columns unless heavy rains fell within 1 day after the application of sewage stopped. Such virus movement could be minimized by the proper management of flooding and drying cycles. PMID:185960
Luo, Xiaofeng; Lone, Todd; Jiang, Songying; Li, Rongrong; Berends, Patrick
2016-07-01
Using survey data from 280 farmers in Jianghan Plain, China, this paper establishes an evaluation index system for three dimensions of farmers' flood perceptions and then uses the entropy method to estimate their overall flood perception. Farmers' flood perceptions exhibit the following characteristics: (i) their flood-occurrence, flood-prevention, and overall flood perceptions gradually increase with age, whereas their flood-effects perception gradually decreases; (ii) their flood-occurrence and flood-effects perceptions gradually increase with a higher level of education, whereas their flood-prevention perception gradually decreases and their overall flood perception shows nonlinear change; (iii) flood-occurrence, flood-effects, and overall flood perceptions are higher among farmers who serve in public offices than among those who do not do so; (iv) the flood-occurrence, flood-effects, and overall flood perceptions of farmers who work off-farm are higher than those of farmers who work solely on-farm, contrary to the flood-prevention perception; and (v) the flood-effects and flood-prevention perceptions of male farmers are lower than those of female farmers, but the flood-occurrence and overall flood perceptions of male farmers are higher than those of female farmers. © 2016 The Author(s). Disasters © Overseas Development Institute, 2016.
Flood Risk Management in Iowa through an Integrated Flood Information System
NASA Astrophysics Data System (ADS)
Demir, Ibrahim; Krajewski, Witold
2013-04-01
The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 1100 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview and live demonstration of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.
DOT National Transportation Integrated Search
2012-04-01
Licking County, Ohio, has experienced numerous floods with the majority of flood damages occurring in the central and south-central areas of the county along four streams: the Licking River, North Fork Licking River, South Fork Licking River, and Rac...
Flynn, Robert H.; Bent, Gardner C.; Lombard, Pamela J.
2016-09-02
The U.S. Geological Survey developed flood elevations in cooperation with the Federal Emergency Management Agency for a 14.3-mile reach of the Green River in Colrain, Leyden, and Greenfield, Massachusetts, to assist landowners and emergency management workers to prepare for and recover from floods. The river reach extends from the U.S. Geological Survey Green River near Colrain, MA (01170100) streamgage downstream to the confluence with the Deerfield River. A series of seven digital flood inundation maps were developed for the upper 4.4 miles of the river reach downstream from the stream. Flood discharges corresponding to the 50-, 10-, 1-, and 0.2-percent annual exceedance probabilities were computed for the reach from updated flood-frequency analyses. These peak flows and the flood flows associated with the stages of 10.2, 12.4, and 14.4 feet (ft) at the Green River streamgage were routed through a one-dimensional step-backwater hydraulic model to obtain the corresponding peak water-surface elevations and to place the Tropical Storm Irene flood of August 28, 2011 (stage 13.97 ft), into historical context. The hydraulic model was calibrated by using the current (2015) stage-discharge relation at the U.S. Geological Survey Green River near Colrain, MA (01170100) streamgage and from documented high-water marks from the Tropical Storm Irene flood, which had a flow higher than a 0.2-percent annual exceedance probability flood discharge.The hydraulic model was used to compute water-surface profiles for flood stages referenced to the streamgage and ranging from the 50-percent annual exceedance probability (bankfull flow) at 7.6 ft (439.8 ft above the North American Vertical Datum of 1988 [NAVD 88]) to 14.4 ft (446.7 ft NAVD 88), which exceeds the maximum recorded water level of 13.97 ft (Tropical Storm Irene) at the streamgage. The mapped stages of 7.6 to 14.4 ft were selected to match the stages for bankfull; the 50-, 10-, 1-, and 0.2-percent annual exceedance probabilities; incremental stages of 10.2 and 12.4 ft; and the maximum stage of the stage-discharge rating curve. The simulated water-surface profiles were combined with a geographic information system digital elevation model derived from light detection and ranging (lidar) data having a 0.5-ft vertical accuracy to create a set of flood-inundation maps.The availability of the flood-inundation maps, combined with information regarding near real-time stage from U.S. Geological Survey Green River near Colrain, MA (01170100) streamgage, can provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, and postflood recovery efforts. The flood-inundation maps are nonregulatory but provide Federal, State, and local agencies and the public with estimates of the potential extent of flooding during selected peak-flow events.
NASA Astrophysics Data System (ADS)
Wyard, Coraline; Fettweis, Xavier
2016-04-01
As a consequence of climate change, several studies concluded that winter flood occurrence could increase in the future in many rivers of northern and western Europe in response to an increase in extreme precipitation events. This study aims to determine if trends in extreme hydroclimatic events generating floods can already be detected over the last century. In particular, we focus on the Ourthe River (southeast of Belgium) which is one of the main tributaries of the Meuse River with a catchment area of 3500 km². In this river, most of the floods occur during winter and about 50% of them are due to rainfall events associated with the melting of the snow which covers the Ardennes during winter. In this study, hydroclimatic conditions favorable to flooding were reconstructed over the 20th century using the regional climate model MAR ("Modèle Atmosphérique Régional") forced by the following reanalyses: the ERA-20C, the ERA-Interim and the NCEP/NCAR-v1. The use of the MAR model allows to compute precipitation, snow depth and run-off resulting from precipitation events and snow melting in any part of the Ourthe river catchment area. Therefore, extreme hydroclimatic events, namely extreme run-off events, which could potentially generate floods, can be reconstructed using the MAR model. As validation, the MAR results were compared to weather station-based data. A trend analysis was then performed in order to study the evolution of conditions favorable to flooding in the Ourthe River catchment. The results show that the MAR model allows the detection of more than 95% of the hydroclimatic conditions which effectively generated observed floods in the Ourthe River over the 1974-2014 period. Conditions favorable to flooding present a negative trend over the last 50 years as a result of a decrease in snow accumulation and in extreme precipitation events. However, significance of these trends depends on the reanalysis used to force the regional climate model as well as the length of the time series.
NASA Astrophysics Data System (ADS)
Wang, Y.; Chang, J.; Guo, A.
2017-12-01
Traditional flood risk analysis focuses on the probability of flood events exceeding the design flood of downstream hydraulic structures while neglecting the influence of sedimentation in river channels on flood control systems. Given this focus, a univariate and copula-based bivariate hydrological risk framework focusing on flood control and sediment transport is proposed in the current work. Additionally, the conditional probabilities of occurrence of different flood events under various extreme precipitation scenarios are estimated by exploiting the copula model. Moreover, a Monte Carlo-based algorithm is used to evaluate the uncertainties of univariate and bivariate hydrological risk. Two catchments located on the Loess plateau are selected as study regions: the upper catchments of the Xianyang and Huaxian stations (denoted as UCX and UCH, respectively). The results indicate that (1) 2-day and 3-day consecutive rainfall are highly correlated with the annual maximum flood discharge (AMF) in UCX and UCH, respectively; and (2) univariate and bivariate return periods, risk and reliability for the purposes of flood control and sediment transport are successfully estimated. Sedimentation triggers higher risks of damaging the safety of local flood control systems compared with the AMF, exceeding the design flood of downstream hydraulic structures in the UCX and UCH. Most importantly, there was considerable sampling uncertainty in the univariate and bivariate hydrologic risk analysis, which would greatly challenge measures of future flood mitigation. The proposed hydrological risk framework offers a promising technical reference for flood risk analysis in sandy regions worldwide.
SERVIR-Africa: Developing an Integrated Platform for Floods Disaster Management in Africa
NASA Technical Reports Server (NTRS)
Macharia, Daniel; Korme, Tesfaye; Policelli, Fritz; Irwin, Dan; Adler, Bob; Hong, Yang
2010-01-01
SERVIR-Africa is an ambitious regional visualization and monitoring system that integrates remotely sensed data with predictive models and field-based data to monitor ecological processes and respond to natural disasters. It aims addressing societal benefits including floods and turning data into actionable information for decision-makers. Floods are exogenous disasters that affect many parts of Africa, probably second only to drought in terms of social-economic losses. This paper looks at SERVIR-Africa's approach to floods disaster management through establishment of an integrated platform, floods prediction models, post-event flood mapping and monitoring as well as flood maps dissemination in support of flood disaster management.
Fall rice straw management and winter flooding treatment effects on a subsequent soybean crop
Anders, M.M.; Windham, T.E.; McNew, R.W.; Reinecke, K.J.
2005-01-01
The effects of fall rice (Oryza sativa L.) straw management and winter flooding on the yield and profitability of subsequent irrigated and dryland soybean [Glycine max (L.) Merr.] crops were studied for 3 years. Rice straw treatments consisted of disking, rolling, or standing stubble. Winter flooding treatments consisted of maintaining a minimum water depth of 10 cm by pumping water when necessary, impounding available rainfall, and draining fields to prevent flooding. The following soybean crop was managed as a conventional-tillage system or no-till system. Tillage system treatments were further divided into irrigated or dryland. Results indicated that there were no significant effects from either fall rice straw management or winter flooding treatments on soybean seed yields. Soybean seed yields for, the conventional tillage system were significantly greater than those for the no-till system for the first 2 yrs and not different in the third year. Irrigated soybean seed yields were significantly greater than those from dryland plots for all years. Net economic returns averaged over the 3 yrs were greatest ($390.00 ha-1) from the irrigated no-till system.
Mano, Y; Omori, F
2013-10-01
Nicaraguan teosinte (Zea nicaraguensis), a species found in frequently flooded areas, provides useful germplasm for breeding flooding-tolerant maize (Z. mays subsp. mays). The objective of this study was to select flooding-tolerant lines using a library of introgression lines (ILs), each containing a chromosome segment from Z. nicaraguensis in the maize inbred line Mi29. To produce the ILs, a single F1 plant derived from a cross between maize Mi29 and Z. nicaraguensis was backcrossed to Mi29 three times, self-pollinated four times and genotyped using simple sequence repeat markers. Flooding tolerance was evaluated at the seedling stage under reducing soil conditions. By backcrossing and selfing, a series of 45 ILs were developed covering nearly the entire maize genome. Five flooding-tolerant lines were identified from among the ILs by evaluating leaf injury. Among these, line IL#18, containing a Z. nicaraguensis chromosome segment on the long arm of chromosome 4, showed the greatest tolerance to flooding, suggesting the presence of a major quantitative trait locus (QTL) in that region. The presence of the QTL was verified by examining flooding tolerance in a population segregating for the candidate region of chromosome 4. There was no significant relationship between the capacity to form constitutive aerenchyma and flooding tolerance in the ILs, indicating the presence of other factors related to flooding tolerance under reducing soil conditions. A flooding-tolerant genotype, IL#18, was identified; this genotype should be useful for maize breeding. In addition, because the chromosome segments of Z. nicaraguensis in the ILs cover nearly the entire genome and Z. nicaraguensis possesses several unique traits related to flooding tolerance, the ILs should be valuable material for additional QTL detection and the development of flooding-tolerant maize lines.
Floods of the Maros river in the early modern and modern period (16th-20th centuries)
NASA Astrophysics Data System (ADS)
Kiss, Andrea
2016-04-01
In the poster presentation a series of historical and recent floods of the Maros river, with special emphasis on the flood events occurred on the lower sections, are presented. Similar to the Hungarian flood databases of the Middle-Danube and Lower-Tisza, the main sources of investigations are the institutional (legal-administrative) documentary evidence (e.g. Szeged and Makó town council protocols and related administrative documentation, Csanád County meeting protocols) mainly from the late 17th-early 18th century onwards. However, in case of the Maros river there is an increased importance of narrative sources, with special emphasis on the early modern period (16th-17th century): in this case the (mainly Transylvanian) narratives (chronicles, diaries, memoires etc.) written by aristocrats, other noblemen and town citizens have particular importance. In the presentation the frequency of detected flood events, from the mid-16th century onwards (with an outlook on sporadic medieval evidence), is provided; moreover, a 3-scaled magnitude classification and a seasonality analysis are also presented. Floods of the Maros river, especially those of the lower river sections, often cannot be understood and discussed without the floods of the (Lower-)Tisza; thus, a comparison of the two flood series are also a subject of discussion. Unlike the Lower-Tisza, the Maros is prone to winter and early spring ice jam floods: since the floods that belonged to this type (similar to those of the Middle-Danube at Budapest) were the most destructive among the flood events of the river, this flood type, and the greatest flood events (e.g. 1751-1752, 1784) are also presented in more detail.
NASA Technical Reports Server (NTRS)
Ahamed, Aakash; Bolten, John; Doyle, Colin; Fayne, Jessica
2016-01-01
Floods are the costliest natural disaster, causing approximately 6.8 million deaths in the twentieth century alone. Worldwide economic flood damage estimates in 2012 exceed $19 Billion USD. Extended duration floods also pose longer term threats to food security, water, sanitation, hygiene, and community livelihoods, particularly in developing countries. Projections by the Intergovernmental Panel on Climate Change (IPCC) suggest that precipitation extremes, rainfall intensity, storm intensity, and variability are increasing due to climate change. Increasing hydrologic uncertainty will likely lead to unprecedented extreme flood events. As such, there is a vital need to enhance and further develop traditional techniques used to rapidly assess flooding and extend analytical methods to estimate impacted population and infrastructure. Measuring flood extent in situ is generally impractical, time consuming, and can be inaccurate. Remotely sensed imagery acquired from space-borne and airborne sensors provides a viable platform for consistent and rapid wall-to-wall monitoring of large flood events through time. Terabytes of freely available satellite imagery are made available online each day by NASA, ESA, and other international space research institutions. Advances in cloud computing and data storage technologies allow researchers to leverage these satellite data and apply analytical methods at scale. Repeat-survey earth observations help provide insight about how natural phenomena change through time, including the progression and recession of floodwaters. In recent years, cloud-penetrating radar remote sensing techniques (e.g., Synthetic Aperture Radar) and high temporal resolution imagery platforms (e.g., MODIS and its 1-day return period), along with high performance computing infrastructure, have enabled significant advances in software systems that provide flood warning, assessments, and hazard reduction potential. By incorporating social and economic data, researchers can develop systems that automatically quantify the socioeconomic impacts resulting from flood disaster events.
NASA Astrophysics Data System (ADS)
Ahamed, A.; Bolten, J. D.
2016-12-01
Flood disaster events in Southeast Asia result in significant loss of life and economic damage. Remote sensing information systems designed to monitor floods and assess their severity can help governments and international agencies formulate an effective response before and during flood events, and ultimately alleviate impacts to population, infrastructure, and agriculture. Recent examples of destructive flood events in the Lower Mekong River Basin occurred in 2000, 2011, and 2013. Floods can be particularly costly in the developing countries of Southeast Asia where large portions of the population live on or near the floodplain (Jonkman, 2005; Kirsch et al., 2012; Long and Trong, 2001; Stromberg. 2007). Regional studies (Knox, 1993; Mirza, 2002; Schiermeier, 2011; Västilä et al, 2010) and Intergovernmental Panel on Climate Change (IPCC, 2007) projections suggest that precipitation extremes and flood frequency are increasing. Thus, improved systems to rapidly monitor flooding in vulnerable areas are needed. This study determines surface water extent for current and historic flood events by using stacks of historic multispectral Moderate-resolution Imaging Spectroradiometer (MODIS) 250-meter imagery and the spectral Normalized Difference Vegetation Index (NDVI) signatures of permanent water bodies (MOD44W). Supporting software tools automatically assess flood impacts to population and infrastructure to provide a rapid first set of impact numbers generated hours after the onset of an event. The near real-time component uses twice daily imagery acquired at 3-hour latency, and performs image compositing routines to minimize cloud cover. Case studies for historic flood events are presented. Results suggest that near real-time remote sensing-based observation and impact assessment systems can serve as effective regional decision support tools for governments, international agencies, and disaster responders.
The Impact of the Extreme Amazonian Flood Season on the Incidence of Viral Gastroenteritis Cases.
Vieira, Carmen Baur; de Abreu Corrêa, Adriana; de Jesus, Michele Silva; Luz, Sérgio Luiz Bessa; Wyn-Jones, Peter; Kay, David; Rocha, Mônica Simões; Miagostovich, Marize Pereira
2017-06-01
During the Amazonian flood season in 2012, the Negro River reached its highest level in 110 years, submerging residential and commercial areas which appeared associated with an elevation in the observed gastroenteritis cases in the city of Manaus. The aim of this study was to evaluate the microbiological water quality of the Negro River basin during this extreme flood to investigate this apparent association between the illness cases and the population exposed to the contaminated waters. Forty water samples were collected and analysed for classic and emerging enteric viruses. Human adenoviruses, group A rotaviruses and genogroup II noroviruses were detected in 100, 77.5 and 27.5% of the samples, respectively, in concentrations of 10 3 -10 6 GC/L. All samples were compliant with local bacteriological standards. HAdV2 and 41 and RVA G2, P[6], and P[8] were characterised. Astroviruses, sapoviruses, genogroup IV noroviruses, klasseviruses, bocaviruses and aichiviruses were not detected. Statistical analyses showed correlations between river stage level and reported gastroenteritis cases and, also, significant differences between virus concentrations during this extreme event when compared with normal dry seasons and previous flood seasons of the Negro River. These findings suggest an association between the extreme flood experienced and gastrointestinal cases in the affected areas providing circumstantial evidence of causality between the elevations in enteric viruses in surface waters and reported illness.
A National Assessment of Changes in Flood Exposure in the United States
NASA Astrophysics Data System (ADS)
Lam, N.; Qiang, Y.; Cai, H.; Zou, L.
2017-12-01
Analyzing flood exposure and its temporal trend is the first step toward understanding flood risk, flood hazard, and flood vulnerability. This presentation is based on a national, county-based study assessing the changes in population and urban areas in high-risk flood zones from 2001-2011 in the contiguous United States. Satellite land use land cover data, Federal Emergency Management Agency (FEMA)'s 100-year flood maps, and census data were used to extract the proportion of developed (urban) land in flood zones by county in the two time points, and indices of difference were calculated. Local Moran's I statistic was applied to identify hotspots of increase in urban area in flood zones, and geographically weighted regression was used to estimate the population in flood zones from the land cover data. Results show that in 2011, an estimate of about 25.3 million people (8.3% of the total population) lived in the high-risk flood zones. Nationally, the ratio of urban development in flood zones is less than the ratio of land in flood zones, implying that Americans were responsive to flood hazards by avoiding development in flood zones. However, this trend varied from place to place, with coastal counties having less urban development in flood zones than the inland counties. Furthermore, the contrast between coastal and inland counties increased during 2001-2011. Finally, several exceptions from the trend (hotspots) were detected, most notably New York City and Miami where significant increases in urban development in flood zones were found. This assessment provides important baseline information on the spatial patterns of flood exposure and their changes from 2001-2011. The study pinpoints regions that may need further investigations and better policy to reduce the overall flood risks. Methodologically, the study demonstrates that pixelated land cover data can be integrated with other natural and human data to investigate important societal problems. The same methodology can be easily extended worldwide to assess the overall trend as well as identify hotspots that need further attention.
NASA Astrophysics Data System (ADS)
Janik, Grzegorz; Dawid, Małgorzata; Walczak, Amadeusz; Słowińska-Osypiuk, Joanna; Skierucha, Wojciech; Wilczek, Andrzej; Daniel, Anna
2017-03-01
Failures of earthen flood protection structures cause enormous material loss. Despite this, in the majority these are structures that were built decades ago. As an example, in Poland, the time of operation of approximately three quarters of existing levees and embankments is over 40 years. A similar situation exists in many other European countries. In the period 1998-2009 the economic losses caused by floods amounted to over 60 thousand million Euro. This accounts for approximately one third of the total losses caused by environmental factors. Ruptures of embankments or levees occur as a result of long-lasting elevated water levels in rivers, and such events are always preceded by changes in their internal structure. Such changes cannot be detected from the outside. This paper presents a new method, never used before, for the determination of changes in the internal structure of the body of a levee. The dynamics of the displacements is described by means of new mathematical formulae. The input data necessary for their application include the dynamics of changes in the value of volumetric moisture that is measured with a freely selected short time step by means of the time-domain-reflectrometry technique. The formulae were created on the basis of hitherto unnoticed and uninterpreted drops in moisture a moment before and a moment after the saturation of inner spaces of the levee body. The results obtained from calculations were compared with data from measurements on a physical model of a levee. The settlement values calculated using the method proposed are convergent with those of the true settlement. The maximum relative error was as low as 19%. The method proposed permits the location of changes in the internal structure of a levee before its rupture. Its application is the main component of a system of early warning against floods.
NASA Astrophysics Data System (ADS)
Ragettli, S.; Zhou, J.; Wang, H.; Liu, C.; Guo, L.
2017-12-01
Flash floods in small mountain catchments are one of the most frequent causes of loss of life and property from natural hazards in China. Hydrological models can be a useful tool for the anticipation of these events and the issuing of timely warnings. One of the main challenges of setting up such a system is finding appropriate model parameter values for ungauged catchments. Previous studies have shown that the transfer of parameter sets from hydrologically similar gauged catchments is one of the best performing regionalization methods. However, a remaining key issue is the identification of suitable descriptors of similarity. In this study, we use decision tree learning to explore parameter set transferability in the full space of catchment descriptors. For this purpose, a semi-distributed rainfall-runoff model is set up for 35 catchments in ten Chinese provinces. Hourly runoff data from in total 858 storm events are used to calibrate the model and to evaluate the performance of parameter set transfers between catchments. We then present a novel technique that uses the splitting rules of classification and regression trees (CART) for finding suitable donor catchments for ungauged target catchments. The ability of the model to detect flood events in assumed ungauged catchments is evaluated in series of leave-one-out tests. We show that CART analysis increases the probability of detection of 10-year flood events in comparison to a conventional measure of physiographic-climatic similarity by up to 20%. Decision tree learning can outperform other regionalization approaches because it generates rules that optimally consider spatial proximity and physical similarity. Spatial proximity can be used as a selection criteria but is skipped in the case where no similar gauged catchments are in the vicinity. We conclude that the CART regionalization concept is particularly suitable for implementation in sparsely gauged and topographically complex environments where a proximity-based regionalization concept is not applicable.
The state of the art of flood forecasting - Hydrological Ensemble Prediction Systems
NASA Astrophysics Data System (ADS)
Thielen-Del Pozo, J.; Pappenberger, F.; Salamon, P.; Bogner, K.; Burek, P.; de Roo, A.
2010-09-01
Flood forecasting systems form a key part of ‘preparedness' strategies for disastrous floods and provide hydrological services, civil protection authorities and the public with information of upcoming events. Provided the warning leadtime is sufficiently long, adequate preparatory actions can be taken to efficiently reduce the impacts of the flooding. Because of the specific characteristics of each catchment, varying data availability and end-user demands, the design of the best flood forecasting system may differ from catchment to catchment. However, despite the differences in concept and data needs, there is one underlying issue that spans across all systems. There has been an growing awareness and acceptance that uncertainty is a fundamental issue of flood forecasting and needs to be dealt with at the different spatial and temporal scales as well as the different stages of the flood generating processes. Today, operational flood forecasting centres change increasingly from single deterministic forecasts to probabilistic forecasts with various representations of the different contributions of uncertainty. The move towards these so-called Hydrological Ensemble Prediction Systems (HEPS) in flood forecasting represents the state of the art in forecasting science, following on the success of the use of ensembles for weather forecasting (Buizza et al., 2005) and paralleling the move towards ensemble forecasting in other related disciplines such as climate change predictions. The use of HEPS has been internationally fostered by initiatives such as "The Hydrologic Ensemble Prediction Experiment" (HEPEX), created with the aim to investigate how best to produce, communicate and use hydrologic ensemble forecasts in hydrological short-, medium- und long term prediction of hydrological processes. The advantages of quantifying the different contributions of uncertainty as well as the overall uncertainty to obtain reliable and useful flood forecasts also for extreme events, has become evident. However, despite the demonstrated advantages, worldwide the incorporation of HEPS in operational flood forecasting is still limited. The applicability of HEPS for smaller river basins was tested in MAP D-Phase, an acronym for "Demonstration of Probabilistic Hydrological and Atmospheric Simulation of flood Events in the Alpine region" which was launched in 2005 as a Forecast Demonstration Project of World Weather Research Programme of WMO, and entered a pre-operational and still active testing phase in 2007. In Europe, a comparatively high number of EPS driven systems for medium-large rivers exist. National flood forecasting centres of Sweden, Finland and the Netherlands, have already implemented HEPS in their operational forecasting chain, while in other countries including France, Germany, Czech Republic and Hungary, hybrids or experimental chains have been installed. As an example of HEPS, the European Flood Alert System (EFAS) is being presented. EFAS provides medium-range probabilistic flood forecasting information for large trans-national river basins. It incorporates multiple sets of weather forecast including different types of EPS and deterministic forecasts from different providers. EFAS products are evaluated and visualised as exceedance of critical levels only - both in forms of maps and time series. Different sources of uncertainty and its impact on the flood forecasting performance for every grid cell has been tested offline but not yet incorporated operationally into the forecasting chain for computational reasons. However, at stations where real-time discharges are available, a hydrological uncertainty processor is being applied to estimate the total predictive uncertainty from the hydrological and input uncertainties. Research on long-term EFAS results has shown the need for complementing statistical analysis with case studies for which examples will be shown.
The Impact of Corps Flood Control Reservoirs in the June 2008 Upper Mississippi Flood
NASA Astrophysics Data System (ADS)
Charley, W. J.; Stiman, J. A.
2008-12-01
The US Army Corps of Engineers is responsible for a multitude of flood control project on the Mississippi River and its tributaries, including levees that protect land from flooding, and dams to help regulate river flows. The first six months of 2008 were the wettest on record in the upper Mississippi Basin. During the first 2 weeks of June, rainfall over the Midwest ranged from 6 to as much as 16 inches, overwhelming the flood protection system, causing massive flooding and damage. Most severely impacted were the States of Iowa, Illinois, Indiana, Missouri, and Wisconsin. In Iowa, flooding occurred on almost every river in the state. On the Iowa River, record flooding occurred from Marshalltown, Iowa, downstream to its confluence with the Mississippi River. At several locations, flooding exceeded the 500-year event. The flooding affected agriculture, transportation, and infrastructure, including homes, businesses, levees, and other water-control structures. It has been estimated that there was at least 7 billion dollars in damages. While the flooding in Iowa was extraordinary, Corps of Engineers flood control reservoirs helped limit damage and prevent loss of life, even though some reservoirs were filled beyond their design capacity. Coralville Reservoir on the Iowa River, for example, filled to 135% of its design flood storage capacity, with stage a record five feet over the crest of the spillway. In spite of this, the maximum reservoir release was limited to 39,500 cfs, while a peak inflow of 57,000 cfs was observed. CWMS, the Corps Water Management System, is used to help regulate Corps reservoirs, as well as track and evaluate flooding and flooding potential. CWMS is a comprehensive data acquisition and hydrologic modeling system for short-term decision support of water control operations in real time. It encompasses data collection, validation and transformation, data storage, visualization, real time model simulation for decision-making support, and data dissemination. The system uses precipitation and flow data, collected in real-time, along with forecasted flow from the National Weather Service to model and optimize reservoir operations and forecast downstream flows and stages, providing communities accurate and timely information to aid their flood-fighting. This involves integrating several simulation modeling programs, including HEC-HMS to forecast flows, HEC-ResSim to model reservoir operations and HEC-RAS to compute forecasted stage hydrographs. An inundation boundary and depth map of water in the flood plain can be calculated from the HEC-RAS results using ArcInfo. By varying future precipitation and releases, engineers can evaluate different "What if?" scenarios. The effectiveness of this tool and Corps reservoirs are examined.
Risk to life due to flooding in post-Katrina New Orleans
NASA Astrophysics Data System (ADS)
Miller, A.; Jonkman, S. N.; Van Ledden, M.
2014-01-01
After the catastrophic flooding of New Orleans due to hurricane Katrina in the year 2005, the city's hurricane protection system has been improved to provide protection against a hurricane load with a 1/100 per year exceedance frequency. This paper investigates the risk to life in post-Katrina New Orleans. In a risk-based approach the probabilities and consequences of various flood scenarios have been analyzed for the central area of the city (the metro bowl) to give a preliminary estimate of the risk to life in the post-Katrina situation. A two-dimensional hydrodynamic model has been used to simulate flood characteristics of various breaches. The model for estimation of fatality rates is based on the loss of life data for Hurricane Katrina. Results indicate that - depending on the flood scenario - the estimated loss of life in case of flooding ranges from about 100 to nearly 500, with the highest life loss due to breaching of the river levees leading to large flood depths. The probability and consequence estimates are combined to determine the individual risk and societal risk for New Orleans. When compared to risks of other large scale engineering systems (e.g. other flood prone areas, dams and the nuclear sector) and acceptable risk criteria found in literature, the risks for the metro bowl are found to be relatively high. Thus, despite major improvements to the flood protection system, the flood risk of post-Katrina New Orleans is still expected to be significant. Effects of reduction strategies on the risk level are discussed as a basis for further evaluation.
Development of a smart flood warning system in urban areas: A case study of Huwei area in Taiwan
NASA Astrophysics Data System (ADS)
Yang, Sheng-Chi; Hsu, Hao-Ming; Kao, Hong-Ming
2016-04-01
In this study, we developed a smart flood warning system to clearly understand flood propagations in urban areas. The science and technology park of Huwei, located in the southwest of Taiwan, was selected as a study area. It was designated to be an important urban area of optoelectronics and biotechnology. The region has an area about 1 km2 with approximately 1 km in both length and width. The discrepancy between the highest and lowest elevations is 6.3 m and its elevation decreases along the northeast to the southwest. It is an isolated urban drainage area due to its urban construction plan. The storm sewer system in this region includes three major networks that collect the runoff and drain to the detention pond where is located in the southwest corner of the region. The proposed smart flood warning system combines three important parts, i.e. the physical world, the cyber-physical interface, and the cyber space, to identify how the flood affects urban areas from now until the next three hours. In the physical world, when a rainfall event occurs, monitoring sensors (e.g. rainfall gauges and water level gauges built in the sewer system and ground surface), which are established in several essential locations of the study area, collect in situ hydrological data and then these data being transported to the cyber-physical interface. The cyber-physical interface is a data preprocess space that includes data analysis, quality control and assurance, and data integration and standardization to produce the validated data. In the cyber space, it has missions to receive the validated data from the cyber-physical interface and to run the time machine that has flood analyses of data mining, inundation scenarios simulation, risk and economic assessments, and so on, based on the validated data. After running the time machine, it offers the analyzed results related to flooding planning, mitigation, response, and recovery. According to the analyzed results, the decision supporting system, therefore, can publish warning information in urban areas at the right time. Keywords: flood warning system, flood mitigation, inundation.
Souza, Sarah C R; Mazzafera, Paulo; Sodek, Ladaslav
2016-05-01
Nitrogen fixation of the nodule of soybean is highly sensitive to oxygen deficiency such as provoked by waterlogging of the root system. This study aimed to evaluate the effects of flooding on N metabolism in nodules of soybean. Flooding resulted in a marked decrease of asparagine (the most abundant amino acid) and a concomitant accumulation of γ-aminobutyric acid (GABA). Flooding also resulted in a strong reduction of the incorporation of (15)N2 in amino acids. Nodule amino acids labelled before flooding rapidly lost (15)N during flooding, except for GABA, which initially increased and declined slowly thereafter. Both nitrogenase activity and the expression of nifH and nifD genes were strongly decreased on flooding. Expression of the asparagine synthetase genes SAS1 and SAS2 was reduced, especially the former. Expression of genes encoding the enzyme glutamic acid decarboxylase (GAD1, GAD4, GAD5) was also strongly suppressed except for GAD2 which increased. Almost all changes observed during flooding were reversible after draining. Possible changes in asparagine and GABA metabolism that may explain the marked fluctuations of these amino acids during flooding are discussed. It is suggested that the accumulation of GABA has a storage role during flooding stress.
Majalaya Flood Early Warning System: A Community Based Approach
NASA Astrophysics Data System (ADS)
Junnaedhi, I. Dewa Gede A.; Riawan, Edi; Suwarman, Rusmawan; Wahyu Hadi, Tri; Lubis, Atika; Joko Trilaksono, Nurjanna; Rahayu, Rahmawati; Kombara, PrawiraYudha; Waskito, Riki; Ekalaya Oktora, Hendra; Supriatna, Rahmat; Anugrah, Aan; Haq Mudzakkir, Abdul; Setiawan, Wawar
2017-06-01
Majalaya, a small city to the south-east of Bandung, was hit by flood almost every year. From January to June 2016, up to 5 severe floods and 4 moderate floods have hit this city. Although it usually not last for long, but the flood stream could be very rapid, thus have a high potential to bring damage to the city. Starting from 2012, ITB through Weather and Climate Prediction Laboratory (WCPL) has support Garda Caah (flood watcher society in Majalaya) with weather prediction system. In the late 2015, ITB also enhancing Garda Caah observation system by installing several Automatic Weather Station (AWS) and Automatic Water Level Recorder (AWLR) throughout Majalaya upstream area. The instruments itself was supported by a re-insurance company MAIPARK and some was built in house by WCPL. The collaboration between ITB, Garda Caah, and Majalaya citizens has been proved to be mutually beneficial. Garda Caah could get more accurate and faster observation and enhanced knowledge, thus could provide a better flood warning for Majalaya citizens. On the other hand, ITB could get data from observation network, with more efficient way to maintain observation instruments as it done by Garda Caah and other Majalaya citizens.
Surrogate modeling of joint flood risk across coastal watersheds
NASA Astrophysics Data System (ADS)
Bass, Benjamin; Bedient, Philip
2018-03-01
This study discusses the development and performance of a rapid prediction system capable of representing the joint rainfall-runoff and storm surge flood response of tropical cyclones (TCs) for probabilistic risk analysis. Due to the computational demand required for accurately representing storm surge with the high-fidelity ADvanced CIRCulation (ADCIRC) hydrodynamic model and its coupling with additional numerical models to represent rainfall-runoff, a surrogate or statistical model was trained to represent the relationship between hurricane wind- and pressure-field characteristics and their peak joint flood response typically determined from physics based numerical models. This builds upon past studies that have only evaluated surrogate models for predicting peak surge, and provides the first system capable of probabilistically representing joint flood levels from TCs. The utility of this joint flood prediction system is then demonstrated by improving upon probabilistic TC flood risk products, which currently account for storm surge but do not take into account TC associated rainfall-runoff. Results demonstrate the source apportionment of rainfall-runoff versus storm surge and highlight that slight increases in flood risk levels may occur due to the interaction between rainfall-runoff and storm surge as compared to the Federal Emergency Management Association's (FEMAs) current practices.
Emplacement of the youngest flood lava on Mars: A short, turbulent story
Jaeger, W.L.; Keszthelyi, L.P.; Skinner, J.A.; Milazzo, M.P.; McEwen, A.S.; Titus, T.N.; Rosiek, M.R.; Galuszka, D.M.; Howington-Kraus, E.; Kirk, R.L.
2010-01-01
Recently acquired data from the High Resolution Imaging Science Experiment (HiRISE), Context (CTX) imager, and Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard the Mars Reconnaissance Orbiter (MRO) spacecraft were used to investigate the emplacement of the youngest flood-lava flow on Mars. Careful mapping finds that the Athabasca Valles flood lava is the product of a single eruption, and it covers 250,000 km2 of western Elysium Planitia with an estimated 5000-7500 km3 of mafic or ultramafic lava. Calculations utilizing topographic data enhanced with MRO observations to refine the dimensions of the channel system show that this flood lava was emplaced turbulently over a period of only a few to several weeks. This is the first well-documented example of a turbulently emplaced flood lava anywhere in the Solar System. However, MRO data suggest that this same process may have operated in a number of martian channel systems. The magnitude and dynamics of these lava floods are similar to the aqueous floods that are generally believed to have eroded the channels, raising the intriguing possibility that mechanical erosion by lava could have played a role in their incision. ?? 2009.
Emplacement of the youngest flood lava on Mars: A short, turbulent story
Jaeger, W.L.; Keszthelyi, L.P.; Skinner, J.A.; Milazzo, M.P.; McEwen, A.S.; Titus, T.N.; Rosiek, M.R.; Galuszka, D.M.; Howington-Kraus, E.; Kirk, R.L.
2009-01-01
Recently acquired data from the High Resolution Imaging Science Experiment (HiRISE), Context (CTX) imager, and Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard the Mars Reconnaissance Orbiter (MRO) spacecraft were used to investigate the emplacement of the youngest flood-lava flow on Mars. Careful mapping finds that the Athabasca Valles flood lava is the product of a single eruption, and it covers 250,000 km2 of western Elysium Planitia with an estimated 5000-7500 km3 of mafic or ultramafic lava. Calculations utilizing topographic data enhanced with MRO observations to refine the dimensions of the channel system show that this flood lava was emplaced turbulently over a period of only a few to several weeks. This is the first well-documented example of a turbulently emplaced flood lava anywhere in the Solar System. However, MRO data suggest that this same process may have operated in a number of martian channel systems. The magnitude and dynamics of these lava floods are similar to the aqueous floods that are generally believed to have eroded the channels, raising the intriguing possibility that mechanical erosion by lava could have played a role in their incision.
Towards modelling flood protection investment as a coupled human and natural system
NASA Astrophysics Data System (ADS)
O'Connell, P. E.; O'Donnell, G.
2013-06-01
Due to a number of recent high profile flood events and the apparent threat from global warming, governments and their agencies are under pressure to make proactive investments to protect people living in floodplains. However, adopting a proactive approach as a universal strategy is not affordable. It has been argued that delaying expensive and essentially irreversible capital decisions could be a prudent strategy in situations with high future uncertainty. This paper firstly uses Monte Carlo simulation to explore the performance of proactive and reactive investment strategies using a rational cost-benefit approach in a natural system with varying levels of persistence/interannual variability in Annual Maximum Floods. It is found that, as persistence increases, there is a change in investment strategy optimality from proactive to reactive. This could have implications for investment strategies under the increasingly variable climate that is expected with global warming. As part of the emerging holistic approaches to flood risk management, there is increasing emphasis on stakeholder participation in determining where and when flood protection investments are made, and so flood risk management is becoming more people-centred. As a consequence, multiple actors are involved in the decision-making process, and the social sciences are assuming an increasingly important role in flood risk management. There is a need for modelling approaches which can couple the natural and human system elements. It is proposed that Coupled Human and Natural System (CHANS) modelling could play an important role in understanding the motivations, actions and influence of citizens and institutions and how these impact on the effective delivery of flood protection investment. A framework for using Agent Based Modelling of human activities leading to flood investments is outlined, and some of the challenges associated with implementation are discussed.
Towards modelling flood protection investment as a coupled human and natural system
NASA Astrophysics Data System (ADS)
O'Connell, P. E.; O'Donnell, G.
2014-01-01
Due to a number of recent high-profile flood events and the apparent threat from global warming, governments and their agencies are under pressure to make proactive investments to protect people living in floodplains. However, adopting a proactive approach as a universal strategy is not affordable. It has been argued that delaying expensive and essentially irreversible capital decisions could be a prudent strategy in situations with high future uncertainty. This paper firstly uses Monte Carlo simulation to explore the performance of proactive and reactive investment strategies using a rational cost-benefit approach in a natural system with varying levels of persistence/interannual variability in annual maximum floods. It is found that, as persistence increases, there is a change in investment strategy optimality from proactive to reactive. This could have implications for investment strategies under the increasingly variable climate that is expected with global warming. As part of the emerging holistic approaches to flood risk management, there is increasing emphasis on stakeholder participation in determining where and when flood protection investments are made, and so flood risk management is becoming more people-centred. As a consequence, multiple actors are involved in the decision-making process, and the social sciences are assuming an increasingly important role in flood risk management. There is a need for modelling approaches which can couple the natural and human system elements. It is proposed that coupled human and natural system (CHANS) modelling could play an important role in understanding the motivations, actions and influence of citizens and institutions and how these impact on the effective delivery of flood protection investment. A framework for using agent-based modelling of human activities leading to flood investments is outlined, and some of the challenges associated with implementation are discussed.
Ellis, J Bryan; Lundy, Lian
2016-12-01
The UK 2007 floods resulted in damages estimated to exceed over £4 billion. This triggered a national review of strategic flood risk management (Pitt, 2008) with its recommendations informing and implemented by the Flood and Water Management, Act (FWMA, 2010). Estimating that up to two-thirds of properties flooded in the 2007 event as a direct result of overloaded sewer systems, the FWMA set out an ambitious overhaul of flood risk management approaches including identifying bodies responsible for the management of local flood risk (local municipalities) and the development of over-arching Lead Local Flood Authorities (LLFAs) at a regional level. LLFAs duties include developing local flood risk management strategies and, aligned with this, many LLFAs and local municipalities produced sustainable drainage system (SUDS) guidance notes. In parallel, changes to the national planning policy framework (NPPF) in England give priority to the use of SUDS in new major developments, as does the related Town and Country Planning Order (2015). However, whilst all three pieces of legislation refer to the preferential use of SUDs, these requirements remain "economically proportionate" and thus the inclusion of SUDS within development controls remain desirable - but not mandatory - obligations. Within this dynamic policy context, reignited most recently by the December 2015 floods, this paper examines some of the challenges to the implementation of SUDS in England and Wales posed by the new regulatory frameworks. In particular, it examines how emerging organisational procedures and processes are likely to impact on future SUDS implementation, and highlights the need for further cross-sectoral working to ensure opportunities for cross-sectoral benefits- such as that accrued by reducing stormwater flows within combined sewer systems for water companies, property developers and environmental protection - are not lost. Copyright © 2016 Elsevier Ltd. All rights reserved.
Coastal and Riverine Flood Forecast Model powered by ADCIRC
NASA Astrophysics Data System (ADS)
Khalid, A.; Ferreira, C.
2017-12-01
Coastal flooding is becoming a major threat to increased population in the coastal areas. To protect coastal communities from tropical storms & hurricane damages, early warning systems are being developed. These systems have the capability of real time flood forecasting to identify hazardous coastal areas and aid coastal communities in rescue operations. State of the art hydrodynamic models forced by atmospheric forcing have given modelers the ability to forecast storm surge, water levels and currents. This helps to identify the areas threatened by intense storms. Study on Chesapeake Bay area has gained national importance because of its combined riverine and coastal phenomenon, which leads to greater uncertainty in flood predictions. This study presents an automated flood forecast system developed by following Advanced Circulation (ADCIRC) Surge Guidance System (ASGS) guidelines and tailored to take in riverine and coastal boundary forcing, thus includes all the hydrodynamic processes to forecast total water in the Potomac River. As studies on tidal and riverine flow interaction are very scarce in number, our forecast system would be a scientific tool to examine such area and fill the gaps with precise prediction for Potomac River. Real-time observations from National Oceanic and Atmospheric Administration (NOAA) and field measurements have been used as model boundary feeding. The model performance has been validated by using major historical riverine and coastal flooding events. Hydrodynamic model ADCIRC produced promising predictions for flood inundation areas. As better forecasts can be achieved by using coupled models, this system is developed to take boundary conditions from Global WaveWatchIII for the research purposes. Wave and swell propagation will be fed through Global WavewatchIII model to take into account the effects of swells and currents. This automated forecast system is currently undergoing rigorous testing to include any missing parameters which might provide better and more reliable forecast for the flood affected communities.
Effects of an extreme flood on river morphology (case study: Karoon River, Iran)
NASA Astrophysics Data System (ADS)
Yousefi, Saleh; Mirzaee, Somayeh; Keesstra, Saskia; Surian, Nicola; Pourghasemi, Hamid Reza; Zakizadeh, Hamid Reza; Tabibian, Sahar
2018-03-01
An extreme flood occurred on 14 April 2016 in the Karoon River, Iran. The occurred flood discharge was the highest discharge recorded over the last 60 years in the Karoon River. Using the OLI Landsat images taken on 8 April 2016 (before the flood) and 24 April 2016 (after the flood) the geomorphic effects were detected in different land cover types within the 155-km-long study reach. The results show that the flood significantly affected the channel width and the main effect was high mobilization of channel sediments and severe bank erosion in the meandering reaches. According to field surveys, the flood occupied the channel corridor and even the floodplain parts. However, the channel pattern was not significantly altered, although the results show that the average channel width increased from 192 to 256 m. Statistical results indicate a significant change for active channel width and sinuosity index at 99% confidence level for both indexes. The flood-induced morphological changes varied significantly for different land cover types along the Karoon River. Specifically, the channel has widened less in residential areas than in other land cover types because of the occurrence of bank protection structures. However, the value of bank retreat in residential and protected sides of the Karoon River is more than what we expected during the study of extreme flood.
Fan, Qin; Davlasheridze, Meri
2016-06-01
Climate change is expected to worsen the negative effects of natural disasters like floods. The negative impacts, however, can be mitigated by individuals' adjustments through migration and relocation behaviors. Previous literature has identified flood risk as one significant driver in relocation decisions, but no prior study examines the effect of the National Flood Insurance Program's voluntary program-the Community Rating System (CRS)-on residential location choice. This article fills this gap and tests the hypothesis that flood risk and the CRS-creditable flood control activities affect residential location choices. We employ a two-stage sorting model to empirically estimate the effects. In the first stage, individuals' risk perception and preference heterogeneity for the CRS activities are considered, while mean effects of flood risk and the CRS activities are estimated in the second stage. We then estimate heterogeneous marginal willingness to pay (WTP) for the CRS activities by category. Results show that age, ethnicity and race, educational attainment, and prior exposure to risk explain risk perception. We find significant values for the CRS-creditable mitigation activities, which provides empirical evidence for the benefits associated with the program. The marginal WTP for an additional credit point earned for public information activities, including hazard disclosure, is found to be the highest. Results also suggest that water amenities dominate flood risk. Thus, high amenity values may increase exposure to flood risk, and flood mitigation projects should be strategized in coastal regions accordingly. © 2015 Society for Risk Analysis.
2006-07-26
This MOC image shows gullies a portion of a flood-carved canyon within the larger Kasei Valles system on Mars. This canyon is the result of the very last flood event that poured through the Kasei valleys, long ago
NASA Astrophysics Data System (ADS)
Tellman, B.; Schwarz, B.; Kuhn, C.; Pandey, B.; Schank, C.; Sullivan, J.; Mahtta, R.; Hammet, L.
2016-12-01
21 million people are exposed to flooding every year, and that number is expected to more than double by 2030 due to climate, land use, and demographic change. Cloud to Street, a mission driven science organization, is working to make big and real time data more meaningful to understand both biophysical and social vulnerability to flooding in this changing world. This talk will showcase the science and practice we have built of integrated social and biophysical flood vulnerability assessments based on our work in Uttarakhand, India and Senegal, in conjunction with nonprofits and development banks. We will show developments of our global historical flood database, detected from MODIS and Landsat satellites, used to power machine learning flood exposure models in Google Earth Engine's API. Demonstrating the approach, we will also showcase new approaches in social vulnerability science, from developing data-driven social vulnerability indices in India, to deriving predictive models that explain the social conditions that lead to disproportionate flood damage and fatality in the US. While this talk will draw on examples of completed vulnerability assessments, we will also discuss the possible future for place-based "living" flood vulnerability assessments that are updated each time satellites circle the earth or people add crowd-sourced observations about flood events and social conditions.
Roland, Mark A.; Hoffman, Scott A.
2011-01-01
Streamflow data, water-surface-elevation profiles derived from a Hydrologic Engineering Center River Analysis System hydraulic model, and geographical information system digital elevation models were used to develop a set of 18 flood-inundation maps for an approximately 5-mile reach of the West Branch Susquehanna River near the Borough of Jersey Shore, Pa. The inundation maps were created by the U.S. Geological Survey in cooperation with the Susquehanna River Basin Commission and Lycoming County as part of an ongoing effort by the National Oceanic and Atmospheric Administration's National Weather Service to focus on continued improvements to the flood forecasting and warning abilities in the Susquehanna River Basin and to modernize flood-forecasting methodologies. The maps, ranging from 23.0 to 40.0 feet in 1-foot increments, correspond to river stage at the U.S. Geological Survey streamgage 01549760 at Jersey Shore. The electronic files used to develop the maps were provided to the National Weather Service for incorporation into their Advanced Hydrologic Prediction Service website. The maps are displayed on this website, which serves as a web-based floodwarning system, and can be used to identify areas of predicted flood inundation associated with forecasted flood-peak stages. During times of flooding or predicted flooding, these maps can be used by emergency managers and the public to take proactive steps to protect life and reduce property damage caused by floods.
Floods n' Dams: A Watershed Model.
ERIC Educational Resources Information Center
Milne, Andrew; Etches, John
1996-01-01
Describes an activity meant to illustrate flooding in a watershed as it impinges on human activities. Shows how flood protection can be provided using the natural holding capacity of basins elsewhere in the water system to reduce the impact on the settled flood plain. The activity works well with intermediate and senior level students but can be…
Water resources, chapter 2, part B
NASA Technical Reports Server (NTRS)
1975-01-01
Various applications and projected applications of active microwave instruments for studying water resources. Most applications involve use of an imaging system operating primarily at wavelengths of less than 30 cm (i.e., K-, X-, and L-bands). Discussion is also included concerning longer wavelength nonimaging systems for use in sounding polar glaciers and icecaps (e.g., Greenland and the Antarctic). The section is divided into six topics: (1) stream runoff, drainage basin analysis, and floods, (2) lake detection and fluctuating levels, (3) coastal processes and wetlands, (4) seasonally and permanently frozen (permafrost) ground, (5) solid water resources (snow, ice, and glaciers), and (6) water pollution.
2007 National Small Business Conference: Critical Infrastructure Opportunities
2007-05-18
Flooding of Subway Tunnels From IED Bomber Maximize lives saved – provide time to evacuate Recent advances in inflatable structure technology: • Stronger...Polimetry/ Signal Processing technologies (Radar & Sonar) Low Cost Advanced Composite Structures Low Cost Composite Sandwich Structures and...Ubiquitous Chem/Bio Detect 34 High Impact Technology Solutions Resilient Tunnel Prevent Flooding of Subway Tunnels From IED Bomber Maximize lives saved
NASA Astrophysics Data System (ADS)
Yucel, Ismail; Onen, Alper
2013-04-01
Evidence is showing that global warming or climate change has a direct influence on changes in precipitation and the hydrological cycle. Extreme weather events such as heavy rainfall and flooding are projected to become much more frequent as climate warms. Regional hydrometeorological system model which couples the atmosphere with physical and gridded based surface hydrology provide efficient predictions for extreme hydrological events. This modeling system can be used for flood forecasting and warning issues as they provide continuous monitoring of precipitation over large areas at high spatial resolution. This study examines the performance of the Weather Research and Forecasting (WRF-Hydro) model that performs the terrain, sub-terrain, and channel routing in producing streamflow from WRF-derived forcing of extreme precipitation events. The capability of the system with different options such as data assimilation is tested for number of flood events observed in basins of western Black Sea Region in Turkey. Rainfall event structures and associated flood responses are evaluated with gauge and satellite-derived precipitation and measured streamflow values. The modeling system shows skills in capturing the spatial and temporal structure of extreme rainfall events and resulted flood hydrographs. High-resolution routing modules activated in the model enhance the simulated discharges.
Buajaroen, Hathaichanok
2013-08-01
In Central Thailand basic health care services were affected by a natural disaster in the form of a flood situation. Flood Relief Operations Centers were established from the crisis. Nakhon Pathom Rajabhat University and including the faculty of nursing volunteered to care for those affected and assist in re-establishing a functioning health care system. The aim of this study was to make explicit knowledge of concept, lesson learned, and the process of management for re-establishing a health care service system at a flood victims at Relief Operations Center, Nakhon Pathom Rajabhat University. We used a qualitative design with mixed methods. This involved in-depth interviews, focus group, observational participation and non-observational participation. Key informants included university administrators, instructors, leaders of flood victims and the flood victims. Data was collected during October-December, 2010. Data were analysed using content analysis and compared matrix. We found that the concept and principle of health care services management were community based and involved home care and field hospital services. We had prepared a management system that placed emphasise on a community based approach and holistic caring such as 24h Nursing Clinic Home, visits with family, a referral system, field hospital. The core of management was to achieve integrated instruction started from nursing students were practiced skills as Health promotion and nursing techniques practicum. Rules were established regarding the health care service system. The outcomes of Health Care Service at the Flood Relief Operations Center were direct and sincere help without conditions, administrations concerned and volunteer nursing students instructors, University Officer have sympathetic and charitable with flood victims and environment. Copyright © 2013 College of Emergency Nursing Australasia Ltd. Published by Elsevier Ltd. All rights reserved.
The effects of low impact development on urban flooding under different rainfall characteristics.
Qin, Hua-peng; Li, Zhuo-xi; Fu, Guangtao
2013-11-15
Low impact development (LID) is generally regarded as a more sustainable solution for urban stormwater management than conventional urban drainage systems. However, its effects on urban flooding at a scale of urban drainage systems have not been fully understood particularly when different rainfall characteristics are considered. In this paper, using an urbanizing catchment in China as a case study, the effects of three LID techniques (swale, permeable pavement and green roof) on urban flooding are analyzed and compared with the conventional drainage system design. A range of storm events with different rainfall amounts, durations and locations of peak intensity are considered for holistic assessment of the LID techniques. The effects are measured by the total flood volume reduction during a storm event compared to the conventional drainage system design. The results obtained indicate that all three LID scenarios are more effective in flood reduction during heavier and shorter storm events. Their performance, however, varies significantly according to the location of peak intensity. That is, swales perform best during a storm event with an early peak, permeable pavements perform best with a middle peak, and green roofs perform best with a late peak, respectively. The trends of flood reduction can be explained using a newly proposed water balance method, i.e., by comparing the effective storage depth of the LID designs with the accumulative rainfall amounts at the beginning and end of flooding in the conventional drainage system. This paper provides an insight into the performance of LID designs under different rainfall characteristics, which is essential for effective urban flood management. Copyright © 2013 Elsevier Ltd. All rights reserved.
Iowa Flood Information System: Towards Integrated Data Management, Analysis and Visualization
NASA Astrophysics Data System (ADS)
Demir, I.; Krajewski, W. F.; Goska, R.; Mantilla, R.; Weber, L. J.; Young, N.
2012-04-01
The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 500 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview and live demonstration of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.
NASA Astrophysics Data System (ADS)
Demir, I.; Krajewski, W. F.; Goska, R.; Mantilla, R.; Weber, L. J.; Young, N.
2011-12-01
The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 500 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities in advance to help minimize damage of floods. This presentation provides an overview of the tools and interfaces in the IFIS developed to date to provide a platform for one-stop access to flood related data, visualizations, flood conditions, and forecast.
NASA Technical Reports Server (NTRS)
Rehder, J. B. (Principal Investigator)
1973-01-01
The author has identified the following significant results. ERTS-1 has proven to be an effective earth-orbiting monitor of landscape change. Its regional coverage for large areal monitoring has been effective for the detection and mapping of agricultural plowing regions, for general forest cover mapping, for flood mapping, for strip mine mapping, and for short-lived precipitation mapping patterns. Paramount to the entire study has been the temporal coverage provided by ERTS. Without the cyclic coverage on an 18 day basis, temporal coverage would have been inadequate for the detection and mapping of strip mining landscape change, the analysis of agricultural landscape change based on plowing patterns, the analysis of urban-suburban growth changes, and the mapping of the Mississippi River floods. Cost benefits from ERTS are unquestionably superior to aircraft systems in regard to large regional coverage and cyclic temporal parameters. For the analysis of landscape change in large regions such as statewide areas or even areas of 10,000 square miles, ERTS is of cost benefit consideration. Not only does the cost of imagery favor ERTS but the reduction of man-hours using ERTS has been in the magnitude of 1:10.
Effects of changes along the risk chain on flood risk
NASA Astrophysics Data System (ADS)
Duha Metin, Ayse; Apel, Heiko; Viet Dung, Nguyen; Guse, Björn; Kreibich, Heidi; Schröter, Kai; Vorogushyn, Sergiy; Merz, Bruno
2017-04-01
Interactions of hydrological and socio-economic factors shape flood disaster risk. For this reason, assessment of flood risk ideally takes into account the whole flood risk chain from atmospheric processes, through the catchment and river system processes to the damage mechanisms in the affected areas. Since very different processes at various scales are interacting along the flood risk, the impact of the single components is rather unclear. However for flood risk management, it is required to know the controlling factor of flood damages. The present study, using the flood-prone Mulde catchment in Germany, discusses the sensitivity of flood risk to disturbances along the risk chain: How do disturbances propagate through the risk chain? How do different disturbances combine or conflict and affect flood risk? In this sensitivity analysis, the five components of the flood risk change are included. These are climate, catchment, river system, exposure and vulnerability. A model framework representing the complete risk chain is combined with observational data to understand how the sensitivities evolve along the risk chain by considering three plausible change scenarios for each of five components. The flood risk is calculated by using the Regional Flood Model (RFM) which is based on a continuous simulation approach, including rainfall-runoff, 1D river network, 2D hinterland inundation and damage estimation models. The sensitivity analysis covers more than 240 scenarios with different combinations of the five components. It is investigated how changes in different components affect risk indicators, such as the risk curve and expected annual damage (EAD). In conclusion, it seems that changes in exposure and vulnerability seem to outweigh changes in hazard.
USDA-ARS?s Scientific Manuscript database
For large fields, remote sensing might permit plant low moisture status to be detected early, and this may improve drought detection and monitoring. The objective of this study was to determine whether canopy and soil surface reflectance data derived from a handheld spectroradiometer can detect mois...
Bridging the Gap between Chemical Flooding and Independent Oil Producers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stan McCool; Tony Walton; Paul Whillhite
2012-03-31
Ten Kanas oil reservoirs/leases were studied through geological and engineering analysis to assess the potential performance of chemical flooding to recover oil. Reservoirs/leases that have been efficiently waterflooded have the highest performance potential for chemical flooding. Laboratory work to identify efficient chemical systems and to test the oil recovery performance of the systems was the major effort of the project. Efficient chemical systems were identified for crude oils from nine of the reservoirs/leases. Oil recovery performance of the identified chemical systems in Berea sandstone rocks showed 90+ % recoveries of waterflood residual oil for seven crude oils. Oil recoveries increasedmore » with the amount of chemical injected. Recoveries were less in Indiana limestone cores. One formulation recovered 80% of the tertiary oil in the limestone rock. Geological studies for nine of the oil reservoirs are presented. Pleasant Prairie, Trembley, Vinland and Stewart Oilfields in Kansas were the most favorable of the studied reservoirs for a pilot chemical flood from geological considerations. Computer simulations of the performance of a laboratory coreflood were used to predict a field application of chemical flooding for the Trembley Oilfield. Estimates of field applications indicated chemical flooding is an economically viable technology for oil recovery.« less
Global scale predictability of floods
NASA Astrophysics Data System (ADS)
Weerts, Albrecht; Gijsbers, Peter; Sperna Weiland, Frederiek
2016-04-01
Flood (and storm surge) forecasting at the continental and global scale has only become possible in recent years (Emmerton et al., 2016; Verlaan et al., 2015) due to the availability of meteorological forecast, global scale precipitation products and global scale hydrologic and hydrodynamic models. Deltares has setup GLOFFIS a research-oriented multi model operational flood forecasting system based on Delft-FEWS in an open experimental ICT facility called Id-Lab. In GLOFFIS both the W3RA and PCRGLOB-WB model are run in ensemble mode using GEFS and ECMWF-EPS (latency 2 days). GLOFFIS will be used for experiments into predictability of floods (and droughts) and their dependency on initial state estimation, meteorological forcing and the hydrologic model used. Here we present initial results of verification of the ensemble flood forecasts derived with the GLOFFIS system. Emmerton, R., Stephens, L., Pappenberger, F., Pagano, T., Weerts, A., Wood, A. Salamon, P., Brown, J., Hjerdt, N., Donnelly, C., Cloke, H. Continental and Global Scale Flood Forecasting Systems, WIREs Water (accepted), 2016 Verlaan M, De Kleermaeker S, Buckman L. GLOSSIS: Global storm surge forecasting and information system 2015, Australasian Coasts & Ports Conference, 15-18 September 2015,Auckland, New Zealand.
NASA Astrophysics Data System (ADS)
Wiesenegger, H.
2003-04-01
On the {12th} of August 2002 a low pressure system moved slowly from northern Italy towards Slovakia. It continuously carried moist air from the Mediterranean towards the northern rim of the Alps with the effect of wide-spread heavy rainfall in Salzburg and other parts of Austria. Daily precipitation amounts of 100 - 160 mm, in some parts even more, as well as rainfall intensities of 5 - 10 mm/h , combined with well saturated soils lead to a rare flood with a return period of 100 years and more. This rare hydrological event not only caused a national catastrophe with damages of several Billion Euro, but also endangered more than 200,000 people, and even killed some. As floods are dangerous, life-threatening, destructive, and certainly amongst the most frequent and costly natural disasters in terms of human hardship as well as economic loss, a great effort, therefore, has to be made to protect people against negative impacts of floods. In order to achieve this objective, various regulations in land use planning (flood maps), constructive measurements (river regulations and technical constructions) as well as flood warning systems, which are not suitable to prevent big floods, but offer in-time-warnings to minimize the loss of human lives, are used in Austria. HYDRIS (Hydrological Information System for flood forecasting in Salzburg), a modular river basin model, developed at Technical University Vienna and operated by the Hydrological Service of Salzburg, was used during the August 2002 flood providing accurate 3 to 4 hour forecasts within 3 % of the real peak discharge of the fast flowing River Salzach. The August {12^th}} flood was in many ways an exceptional, very fast happening event which took many people by surprise. At the gauging station Salzburg / Salzach (catchment area 4425 {km^2}) it took only eighteen hours from mean annual discharge (178 {m3/s}) to the hundred years flood (2300 {m3/s}). The August flood made clear, that there is a strong need for longer lead times in Salzburg's flood forecasts. Methods to incorporate precipitation forecasts, provided by the Met Office, as well as observations of actual soil conditions, therefore, have to be developed and should enable hydrologists to predict possible scenarios and impacts of floods, forecasted for the next 24 hours. As a further consequence of the August 2002 flood, building regulations, e.g. the use of oil tanks in flood prone areas, have to be checked and were necessary adapted. It is also necessary to make people, who already live in flood prone areas, aware of the dangers of floods. They also need to know about the limits of flood protection measurements and about what happens, if flood protection design values are exceeded. Alarm plans, dissemination of information by using modern communication systems (Internet) as well as communication failure in peak times and co-ordination of rescue units are also a subject to be looked at carefully. The above mentioned measurements are amongst others of a 10 point program, developed by the Government of the Province of Salzburg and at present checked with regards to feasibility. As it is to be expected, that the August 2002 flood was not the last rare one of this century, experience gained should be valuably for the next event.
Developments of the European Flood Awareness System (EFAS)
NASA Astrophysics Data System (ADS)
Thiemig, Vera; Olav Skøien, Jon; Salamon, Peter; Pappenberger, Florian; Wetterhall, Fredrik; Holst, Bo; Asp, Sara-Sophia; Garcia Padilla, Mercedes; Garcia, Rafael J.; Schweim, Christoph; Ziese, Markus
2017-04-01
EFAS (http://www.efas.eu) is an operational system for flood forecasting and early warning for the entire Europe, which is fully operational as part of the Copernicus Emergency Management Service since 2012. The prime aim of EFAS is to gain time for preparedness measures before major flood events - particularly in trans-national river basins - strike. This is achieved by providing complementary, added value information to the national and regional services holding the mandate for flood warning as well as to the ERCC (European Response and Coordination Centre). Using a coherent model for all of Europe forced with a range of deterministic and ensemble weather forecasts, the system can give a probabilistic flood forecast for a medium range lead time (up to 10 days) independent of country borders. The system is under continuous development, and we will present the basic set up, some prominent examples of recent and ongoing developments (such as the rapid impact assessment, seasonal outlook and the extended domain) and the future challenges.
NASA Astrophysics Data System (ADS)
Podhoranyi, M.; Kuchar, S.; Portero, A.
2016-08-01
The primary objective of this study is to present techniques that cover usage of a hydrodynamic model as the main tool for monitoring and assessment of flood events while focusing on modelling of inundation areas. We analyzed the 2010 flood event (14th May - 20th May) that occurred in the Moravian-Silesian region (Czech Republic). Under investigation were four main catchments: Opava, Odra, Olše and Ostravice. Four hydrodynamic models were created and implemented into the Floreon+ platform in order to map inundation areas that arose during the flood event. In order to study the dynamics of the water, we applied an unsteady flow simulation for the entire area (HEC-RAS 4.1). The inundation areas were monitored, evaluated and recorded semi-automatically by means of the Floreon+ platform. We focused on information about the extent and presence of the flood areas. The modeled flooded areas were verified by comparing them with real data from different sources (official reports, aerial photos and hydrological networks). The study confirmed that hydrodynamic modeling is a very useful tool for mapping and monitoring of inundation areas. Overall, our models detected 48 inundation areas during the 2010 flood event.
Using practical and social information to influence flood adaptation behavior
NASA Astrophysics Data System (ADS)
Allaire, Maura C.
2016-08-01
As the prospect for more frequent and severe extreme weather events gains scientific support, many nations are evaluating mitigation and adaptation options. Insurance and home retrofits could reduce household welfare losses due to flood events. Yet even after disasters, households often fail to take risk mitigation actions. This paper presents the first randomized field experiment that tests the effect of information provision on household uptake of flood insurance and home retrofits. A sample of 364 flood-prone households in Bangkok was randomly split into treatment and control groups. The treatment group received practical details on home retrofits and flood insurance as well as social information regarding the insurance purchase decisions of peers. Results indicate that the information intervention increased insurance purchases by about five percentage points, while no effect was detected for home retrofits. This effect is nearly equal to the increase in uptake that the national insurance program in Thailand has achieved through all other means since its establishment in 2012. If scaled up to include all uninsured, flood-prone households in Bangkok, nearly 70,000 additional households could be insured. The results suggest that well-designed information interventions could increase uptake of flood insurance, without additional premium subsidies or mandates.
NASA Astrophysics Data System (ADS)
Doyle, C.; Gao, M.; Spruce, J.; Bolten, J. D.; Weber, S.
2014-12-01
This presentation discusses results of a project to develop a near real time flood monitoring capability for the Lower Mekong Water Basin (LMB), the largest river basin in Southeast Asia and home to more than sixty million people. The region has seen rapid population growth and socio-economic development, fueling unsustainable deforestation, agricultural expansion, and stream-flow regulation. The basin supports substantial rice farming and other agrarian activities, which heavily depend upon seasonal flooding. But, floods due to typhoons and other severe weather events can result in disasters that cost millions of dollars and cause hardships to millions of people. This study uses near real time and historical Aqua and Terra MODIS 250-m resolution Normalized Difference Vegetation Index (NDVI) products to map flood and drought impact within the LMB. In doing so, NDVI change products are derived by comparing from NDVI during the wet season to a baseline NDVI from the dry season. The method records flood events, which cause drastic decreases in NDVI compared to non-flooded conditions. NDVI change product computation was automated for updating a near real-time system, as part of the Committee on Earth Observing Satellites Disaster Risk Management Observation Strategy. The system is a web-based 'Flood Dashboard that will showcase MODIS flood monitoring products, along with other flood mapping and weather data products. This flood dashboard enables end-users to view and assess a variety of geospatial data to monitor floods and flood impacts in near real-time, as well provides a platform for further data aggregation for flood prediction modeling and post-event assessment.
Extraordinary flood response of a small urban watershed to short-duration convective rainfall
Smith, J.A.; Miller, A.J.; Baeck, M.L.; Nelson, P.A.; Fisher, G.T.; Meierdiercks, K.L.
2005-01-01
The 9.1 km2 Moores Run watershed in Baltimore, Maryland, experiences floods with unit discharge peaks exceeding 1 m3 s-1 km-2 12 times yr-1, on average. Few, if any, drainage basins in the continental United States have a higher frequency. A thunderstorm system on 13 June 2003 produced the record flood peak (13.2 m3 s-1 km-2) during the 6-yr stream gauging record of Moores Run. In this paper, the hydrometeorology, hydrology, and hydraulics of extreme floods in Moores Run are examined through analyses of the 13 June 2003 storm and flood, as well as other major storm and flood events during the 2000-03 time period. The 13 June 2003 flood, like most floods in Moores Run, was produced by an organized system of thunderstorms. Analyses of the 13 June 2003 storm, which are based on volume scan reflectivity observations from the Sterling, Virginia, WSR-88D radar, are used to characterize the spatial and temporal variability of flash flood producing rainfall. Hydrology of flood response in Moores Run is characterized by highly efficient concentration of runoff through the storm drain network and relatively low runoff ratios. A detailed survey of high-water marks for the 13 June 2003 flood is used, in combination with analyses based on a 2D, depth-averaged open channel flow model (TELEMAC 2D) to examine hydraulics of the 13 June 2003 flood. Hydraulic analyses are used to examine peak discharge estimates for the 13 June flood peak, propagation of flood waves in the Moores Run channel, and 2D flow features associated with channel and floodplain geometry. ?? 2005 American Meteorological Society.