area process sewer: Topics by Science.gov

Sample records for area process sewer

Remediation of Mercury-Contaminated Storm Sewer Sediments from the West End Mercury Area at the Y-12 National Security Complex in Oak Ridge, Tennessee - 12061

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tremaine, Diana; Douglas, Steven G.

2012-07-01

The Y-12 National Security Complex in Oak Ridge, TN has faced an ongoing challenge from mercury entrapped in soils beneath and adjacent to buildings, storm sewers, and process pipelines. Previous actions to reduce the quantity and/or mobilization of mercury-contaminated media have included plugging of building floor drains, cleaning of sediment and sludge from sumps, manholes, drain lines, and storm sewers, lining/relining of storm sewers and replacement of a portion of the storm sewer trunk line, re-routing and removal of process piping, and installation of the Central Mercury Treatment System to capture and treat contaminated sump water. Despite the success ofmore » these actions, mercury flux in the storm sewer out-falls that discharge to Upper East Fork Poplar Creek (UEFPC) continues to pose a threat to long-term water quality. A video camera survey of the storm sewer network revealed several sections of storm sewer that had large cracks, separations, swells, and accumulations of sediment/sludge and debris. The selected remedy was to clean and line the sections of storm sewer pipe that were determined to be primary contributors to the mercury flux in the storm sewer out-falls. The project, referred to as the West End Mercury Area (WEMA) Storm Sewer Remediation Project, included cleaning sediment and debris from over 2,460 meters of storm sewer pipe followed by the installation of nearly 366 meters of cure-in-place pipe (CIPP) liner. One of the greatest challenges to the success of this project was the high cost of disposal associated with the mercury-contaminated sludge and wastewater generated from the storm sewer cleaning process. A contractor designed and operated an on-site wastewater pre-treatment system that successfully reduced mercury levels in 191 cubic meters of sludge to levels that allowed it to be disposed at Nevada Nuclear Security Site (NNSS) disposal cell as a non-hazardous, low-level waste. The system was also effective at pre-treating over 1,514,000 liters of wastewater to levels that met the waste acceptance criteria for the on-site West End [wastewater] Treatment Facility (WETF). This paper describes the storm sewer cleaning and lining process and the methods used to process the mercury-contaminated sludge and wastewater, as well as several 'lessons learned' that would be relevant to any future projects involving storm sewer cleaning and debris remediation. (authors)« less
A novel approach to model dynamic flow interactions between storm sewer system and overland surface for different land covers in urban areas

NASA Astrophysics Data System (ADS)

Chang, Tsang-Jung; Wang, Chia-Ho; Chen, Albert S.

2015-05-01

In this study, we developed a novel approach to simulate dynamic flow interactions between storm sewers and overland surface for different land covers in urban areas. The proposed approach couples the one-dimensional (1D) sewer flow model (SFM) and the two-dimensional (2D) overland flow model (OFM) with different techniques depending on the land cover type of the study areas. For roads, pavements, plazas, and so forth where rainfall becomes surface runoff before entering the sewer system, the rainfall-runoff process is simulated directly in the 2D OFM, and the runoff is drained to the sewer network via inlets, which is regarded as the input to 1D SFM. For green areas on which rainfall falls into the permeable ground surface and the generated direct runoff traverses terrain, the deduction rate is applied to the rainfall for reflecting the soil infiltration in the 2D OFM. For flat building roofs with drainage facilities allowing rainfall to drain directly from the roof to sewer networks, the rainfall-runoff process is simulated using the hydrological module in the 1D SFM where no rainfall is applied to these areas in the 2D OFM. The 1D SFM is used for hydraulic simulations in the sewer network. Where the flow in the drainage network exceeds its capacity, a surcharge occurs and water may spill onto the ground surface if the pressure head in a manhole exceeds the ground elevation. The overflow discharge from the sewer system is calculated by the 1D SFM and considered a point source in the 2D OFM. The overland flow will return into the sewer network when it reaches an inlet that connects to an un-surcharged manhole. In this case, the inlet is considered as a point sink in the 2D OFM and an inflow to a manhole in the 1D SFM. The proposed approach was compared to other five urban flood modelling techniques with four rainfall events that had previously recorded inundation areas. The merits and drawbacks of each modelling technique were compared and discussed. Based on the simulated results, the proposed approach was found to simulate floodings closer to the survey records than other approaches because the physical rainfall-runoff phenomena in urban environment were better reflected.
Research note: Mapping spatial patterns in sewer age, material, and proximity to surface waterways to infer sewer leakage hotspots

USGS Publications Warehouse

Hopkins, Kristina G.; Bain, Daniel J.

2018-01-01

Identifying areas where deteriorating sewer infrastructure is in close proximity to surface waterways is needed to map likely connections between sewers and streams. We present a method to estimate sewer installation year and deterioration status using historical maps of the sewer network, parcel-scale property assessment data, and pipe material. Areas where streams were likely buried into the sewer system were mapped by intersecting the historical stream network derived from a 10-m resolution digital elevation model with sewer pipe locations. Potential sewer leakage hotspots were mapped by identifying where aging sewer pipes are in close proximity (50-m) to surface waterways. Results from Pittsburgh, Pennsylvania (USA), indicated 41% of the historical stream length was lost or buried and the potential interface between sewers and streams is great. The co-location of aging sewer infrastructure (>75 years old) near stream channels suggests that 42% of existing streams are located in areas with a high potential for sewer leakage if sewer infrastructure fails. Mapping the sewer-stream interface provides an approach to better understand areas were failing sewers may contribute a disproportional amount of nutrients and other pathogens to surface waterways.
Optimization of the central automatic control of a small Dutch sewer system

NASA Astrophysics Data System (ADS)

Kolechkina, A. G.; Hoes, O. A. C.

2012-04-01

A sewer control system was developed in the context of a subsidized project aiming at improvement of surface water quality by control of sewer systems and surface water systems. The project was coordinated by the local water board, "Waterschap Hollandse Delta". Other participants were Delft University of Technology, Deltares and the municipalities Strijen, Cromstrijen, Westmaas, Oud Beijerland and Piershil. As part of the project there were two pilot implementations where a central automatic controller was coupled to the existing SCADA system. For these two pilots the system is now operational. A Dutch urban area in the western part of the Netherlands is usually part of a polder, which is effectively an artificially drained catchment. The urban area itself is split into small subcatchments that manage runoff in different ways. In all cases a large fraction goes into the natural hydrological cycle, but, depending on the design of the local sewer system, a larger or smaller part finds its way into the sewer system. Proper control of this flow is necessary to control surface water quality and to avoid health risks from flow from the sewer into the streets. At each time step the controller switches pumps to distribute the remaining water in the system at the end of the time step over the different subcatchments. The distribution is created based on expert judgment of the relative vulnerability and subcatchment sewer system water quality. It is implemented in terms curves of total system stored volume versus subcatchment stored volume. We describe the process of the adaptation of a controller to two different sewer systems and the understanding of the artificial part of the catchment we gained during this process. In the process of adaptation the type of sewer system (combined foul water and storm water transport or separate foul water and storm water transport) played a major role.
APPROACH TO "FURTHER-REASONABLE-PROGRESS" TO ATTAIN WATER QUALITY STANDARDS

EPA Science Inventory

Watershed managers in urban areas in the US are pursuing optimum strategies or plans for managing wastewater treatment plants, stormwater systems, sanitary sewer overflows (SSO) and combined sewer overflows (CSO). Often these strategies are based on an iterative process or a "fur...
APPROACH TO "FURTHER-REASONABLE-PROGRESS" TO ATTAIN WATER QUALITY STANDARDS

EPA Science Inventory

Watershed managers in urban areas in the US are pursuing optimum strategies or plans for managing wastewater treatment plants, stormwater systems, sanitary sewer overflows (SSO) and combined sewer overflows (CSO). Often thes strategies are based on an iterative process or a "furt...
Disparities in Water and Sewer Services in North Carolina: An Analysis of the Decision-Making Process

PubMed Central

Gibson, Jacqueline MacDonald

2015-01-01

Objectives. We examined the factors that affect access to municipal water and sewer service for unincorporated communities relying on wells and septic tanks. Methods. Using a multisite case study design, we conducted in-depth, semistructured interviews with 25 key informants from 3 unincorporated communities in Hoke, New Hanover, and Transylvania counties, North Carolina, July through September 2013. Interviewees included elected officials, health officials, utility providers, and community members. We coded the interviews in ATLAS.ti to identify common themes. Results. Financing for water and sewer service emerged as the predominant factor that influenced decisions to extend these services. Improved health emerged as a minor factor, suggesting that local officials may not place a high emphasis on the health benefits of extending public water and sewer services. Awareness of failed septic systems in communities can prompt city officials to extend sewer service to these areas; however, failed systems are often underreported. Conclusions. Understanding the health costs and benefits of water and sewer extension and integrating these findings into the local decision-making process may help address disparities in access to municipal services. PMID:26270307
Surface models for coupled modelling of runoff and sewer flow in urban areas.

PubMed

Ettrich, N; Steiner, K; Thomas, M; Rothe, R

2005-01-01

Traditional methods fail for the purpose of simulating the complete flow process in urban areas as a consequence of heavy rainfall and as required by the European Standard EN-752 since the bi-directional coupling between sewer and surface is not properly handled. The new methodology, developed in the EUREKA-project RisUrSim, solves this problem by carrying out the runoff on the basis of shallow water equations solved on high-resolution surface grids. Exchange nodes between the sewer and the surface, like inlets and manholes, are located in the computational grid and water leaving the sewer in case of surcharge is further distributed on the surface. Dense topographical information is needed to build a model suitable for hydrodynamic runoff calculations; in urban areas, in addition, many line-shaped elements like houses, curbs, etc. guide the runoff of water and require polygonal input. Airborne data collection methods offer a great chance to economically gather densely sampled input data.
Stochastic modeling of total suspended solids (TSS) in urban areas during rain events.

PubMed

Rossi, Luca; Krejci, Vladimir; Rauch, Wolfgang; Kreikenbaum, Simon; Fankhauser, Rolf; Gujer, Willi

2005-10-01

The load of total suspended solids (TSS) is one of the most important parameters for evaluating wet-weather pollution in urban sanitation systems. In fact, pollutants such as heavy metals, polycyclic aromatic hydrocarbons (PAHs), phosphorous and organic compounds are adsorbed onto these particles so that a high TSS load indicates the potential impact on the receiving waters. In this paper, a stochastic model is proposed to estimate the TSS load and its dynamics during rain events. Information on the various simulated processes was extracted from different studies of TSS in urban areas. The model thus predicts the probability of TSS loads arising from combined sewer overflows (CSOs) in combined sewer systems as well as from stormwater in separate sewer systems in addition to the amount of TSS retained in treatment devices in both sewer systems. The results of this TSS model illustrate the potential of the stochastic modeling approach for assessing environmental problems.
A model for methane production in sewers.

PubMed

Chaosakul, Thitirat; Koottatep, Thammarat; Polprasert, Chongrak

2014-09-19

Most sewers in developing countries are combined sewers which receive stormwater and effluent from septic tanks or cesspools of households and buildings. Although the wastewater strength in these sewers is usually lower than those in developed countries, due to improper construction and maintenance, the hydraulic retention time (HRT) could be relatively long and resulting considerable greenhouse gas (GHG) production. This study proposed an empirical model to predict the quantity of methane production in gravity-flow sewers based on relevant parameters such as surface area to volume ratio (A/V) of sewer, hydraulic retention time (HRT) and wastewater temperature. The model was developed from field survey data of gravity-flow sewers located in a peri-urban area, central Thailand and validated with field data of a sewer system of the Gold Coast area, Queensland, Australia. Application of this model to improve construction and maintenance of gravity-flow sewers to minimize GHG production and reduce global warming is presented.
Predicting concrete corrosion of sewers using artificial neural network.

PubMed

Jiang, Guangming; Keller, Jurg; Bond, Philip L; Yuan, Zhiguo

2016-04-01

Corrosion is often a major failure mechanism for concrete sewers and under such circumstances the sewer service life is largely determined by the progression of microbially induced concrete corrosion. The modelling of sewer processes has become possible due to the improved understanding of in-sewer transformation. Recent systematic studies about the correlation between the corrosion processes and sewer environment factors should be utilized to improve the prediction capability of service life by sewer models. This paper presents an artificial neural network (ANN)-based approach for modelling the concrete corrosion processes in sewers. The approach included predicting the time for the corrosion to initiate and then predicting the corrosion rate after the initiation period. The ANN model was trained and validated with long-term (4.5 years) corrosion data obtained in laboratory corrosion chambers, and further verified with field measurements in real sewers across Australia. The trained model estimated the corrosion initiation time and corrosion rates very close to those measured in Australian sewers. The ANN model performed better than a multiple regression model also developed on the same dataset. Additionally, the ANN model can serve as a prediction framework for sewer service life, which can be progressively improved and expanded by including corrosion rates measured in different sewer conditions. Furthermore, the proposed methodology holds promise to facilitate the construction of analytical models associated with corrosion processes of concrete sewers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Identification of potential sewer mining locations: a Monte-Carlo based approach.

PubMed

Tsoukalas, I K; Makropoulos, C K; Michas, S N

2017-12-01

Rapid urbanization affecting demand patterns, coupled with potential water shortages due to supply side impacts of climatic changes, has led to the emergence of new technologies for water and wastewater reuse. Sewer mining (SM) is a novel decentralized option that could potentially provide non-potable water for urban uses, including for example the irrigation of urban green spaces, providing a mid-scale solution to effective wastewater reuse. SM is based on extracting wastewater from local sewers and treatment at the point of demand and entails in some cases the return of treatment residuals back to the sewer system. Several challenges are currently in the way of such applications in Europe, including public perception, inadequate regulatory frameworks and engineering issues. In this paper we consider some of these engineering challenges, looking at the sewer network as a system where multiple physical, biological and chemical processes take place. We argue that prior to implementing SM, the dynamics of the sewer system should be investigated in order to identify optimum ways of deploying SM without endangering the reliability of the system. Specifically, both wastewater extraction and sludge return could result in altering the biochemical process of the network, thus unintentionally leading to degradation of the sewer infrastructure. We propose a novel Monte-Carlo based method that takes into account both spatial properties and water demand characteristics of a given area of SM deployment while simultaneously accounting for the variability of sewer network dynamics in order to identify potential locations for SM implementation. The outcomes of this study suggest that the method can provide rational results and useful guidelines for upscale SM technologies at a city level.
An Environmental Innovation: The Sewer Mouse

NASA Technical Reports Server (NTRS)

1979-01-01

In the effort to clean up America's waters, there is a little-known complicating factor: because they leak, sewer systems in many American cities are causing rather than preventing pollution of rivers and lakes. Fixing the leaks is difficult because their locations are unknown. Maintenance crews can't tear up a whole city looking for cracks in the pipes; they must first determine which areas are most likely suspects. An aerospace spinoff is providing help in that regard. The problem starts with heavy rains. Rainwater naturally flows into the sewers from streets, but sewage systems are designed to accommodate it. However, they are not designed to handle the additional flow of "groundwater", rain absorbed by the earth which seeps into the sewers through leaks in pipes and sewer walls. After a storm, groundwater seepage can increase the waterflow to deluge proportions, with the result that sewage treatment plants are incapable of processing the swollen flow. When that happens the sluices must be opened, dumping raw sewage into rivers and lakes.
Relationship between race and community water and sewer service in North Carolina, USA

PubMed Central

MacDonald Gibson, Jacqueline

2018-01-01

Previous evidence has identified potential racial disparities in access to community water and sewer service in peri-urban areas adjacent to North Carolina municipalities. We performed the first quantitative, multi-county analysis of these disparities. Using publicly available data, we identified areas bordering municipalities and lacking community water and/or sewer service in 75 North Carolina counties. Logistic regression was performed to evaluate the relationship between race and access to service in peri-urban areas, controlling for population density, median home value, urban status, and percent white in the adjacent municipality. In the peri-urban areas analyzed, 67% of the population lacked community sewer service, and 33% lacked community water service. In areas other than those with no black residents, odds of having community water service (p<0.01) or at least one of the two services (p<0.05) were highest for census blocks with a small proportion of black residents and lowest in 100% black census blocks, though this trend did not hold for access to community sewer service alone. For example, odds of community water service were 85% higher in areas that were greater than 0% but less than 22% black than in 100% black areas (p<0.001). Peri-urban census blocks without black populations had the lowest odds of community water service, community sewer service, and at least one of the two services, but this difference was only statistically significant for sewer. Peri-urban areas lacking service with no black residents were wealthier than 100% black areas and areas with any percent black greater than 0%. Findings suggest two unserved groups of differing racial and socioeconomic status: (1) lower-income black populations potentially excluded from municipal services during the era of legal racial segregation and (2) higher-income non-black populations. Findings also suggest greater racial disparities in community water than community sewer services statewide. PMID:29561859
Factors affecting economies of scale in combined sewer systems.

PubMed

Maurer, Max; Wolfram, Martin; Anja, Herlyn

2010-01-01

A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.
Contaminant transport pathways between urban sewer networks and water supply wells

USDA-ARS?s Scientific Manuscript database

Water supply wells and sanitary sewers are critical components of urban infrastructure, but sewer leakage threatens the quality of groundwater in sewered areas. Previous work by our group has documented the presence of human enteric viruses in deep public supply wells. Our current research uses such...
Sulfide and methane production in sewer sediments: Field survey and model evaluation.

PubMed

Liu, Yiwen; Tugtas, A Evren; Sharma, Keshab R; Ni, Bing-Jie; Yuan, Zhiguo

2016-02-01

Sewer sediment processes have been reported to significantly contribute to overall sulfide and methane production in sewers, at a scale comparable to that of sewer biofilms. The physiochemical and biological characteristics of sewer sediments are heterogeneous; however, the variability of in-sediments sulfide and methane production rates among sewers has not been assessed to date. In this study, five sewer sediment samples were collected from two cities in Australia with different climatic conditions. Batch assays were conducted to determine the rates of sulfate reduction and methane production under different flow velocity (shear stress) conditions as well as under completely mixed conditions. The tests showed substantial and variable sulfate reduction and methane production activities among different sediments. Sulfate reduction and methane production from sewer sediments were confirmed to be areal processes, and were dependent on flow velocity/shear stress. Despite of the varying characteristics and reactions kinetics, the sulfate reduction and methane production processes in all sediments could be well described by a one-dimensional sewer sediment model recently developed based on results obtained from a laboratory sewer sediment reactor. Model simulations indicated that the in-situ contribution of sewer sediment emissions could be estimated without the requirement of measuring the specific sediment characteristics or the sediment depths. Copyright © 2015 Elsevier Ltd. All rights reserved.
The use of multiple tracers to evaluate the impact of sewered and non-sewered development on coastal water quality in a rural area of Florida.

PubMed

Meeroff, Daniel E; Bloetscher, Frederick; Long, Sharon C; Bocca, Thais

2014-05-01

When onsite wastewater treatment and disposal systems (OSTDS) are not sited appropriately or installed properly, wastewater constituents can be a source of adverse environmental impacts to soil and groundwater, which can lead to potential public health risks. A paired monitoring design developed to compare water quality in sewered and non-sewered areas is presented here. It is suggested as a possible monitoring scheme for assessing the impact of sewer installation projects. As such, two sets of single-family, rural residential Florida neighborhoods were evaluated over a two-year period to gain insight into the effects of small-community use of OSTDS on coastal water quality. One set of two neighborhoods were connected to the sanitary sewer network and the other set of two were served exclusively by OSTDS. Water quality sampling was conducted at the paired sites during seasonal high water table (SHWT) and seasonal low water table (SLWT) events. Measured surface water quality during the SHWT showed indications of environmental impacts from OSTDS in terms of nutrients, microbial pathogen indicators, and other water quality measures, such as turbidity and conductivity. However, during the SLWT events, no obvious impacts attributable to OSTDS were detected. The water quality results indicate that OSTDS impacts may be measureable in rural areas. Other factors, such as microbial indicator survival and regrowth potential, may confound the understanding of water quality impacts of sewer projects. For example, the microbial indicators Escherichia coli and enterococci were found to persist over time and therefore did not always represent true comparisons of OSTDS and sewered areas between seasons. The timeframe for evaluating the effects of sewer projects may be longer than anticipated because of this survival and regrowth phenomenon.
Remote Infrared Thermal Sensing of Sewer Voids, Four-Year Update

NASA Astrophysics Data System (ADS)

Weil, Gary J.

1988-01-01

When a sewer caves in, it often takes the street, sidewalks, and surrounding buildings along for the ride. These collapses endanger public health and safety. Repairing a sewer before such a cave-in is obviously the preferred method. Emergency repairs cost far more than prevention measures - often millions of dollars more. Many combined sewers in the St. Louis area, as in many of America's cities, are more than 125 years old and are subject to structural failure. In 1981 alone, St. Louis had 4,000 sewer collapses and an astronomical repair bill. These and similar problems have been described as "a crisis of national proportions. The question addressed by this paper is how to detect unseen problem areas in sewer systems before they give way. At the present, progressive sewer administrations may use crawl crews to inspect sewers when problems are suspected. This can be extremely costly and dangerous, and a void around the outside of the sewer is often invisible from within. Thus, even a crawl crew can fail to detect most voids. Infrared Thermography has been found by sewer districts and independent evaluation engineering firms to be an extremely accurate method of finding sewer voids, before they can cause expensive and dangerous problems. This technique uses a non-contact, remote sensing method, with the potential for surveying large areas quickly and efficiently. This paper reviews our initial paper presented to The International Society for Optical Engineering in October of 1983 and presents an update of our experience, both successes and failures, in several large-scale void detection projects. Infrared Thermographic techniques of non-destructive testing will have major implications for cities and for the engineering profession because it promises to make the crisis of infrastructure repair and rehabilitation more manageable. Intelligent, systematic use of this relatively low cost void detection method, Infrared Thermography, may revolutionize the way sewer problems are handled in the future.
Contributions of wastewater, runoff and sewer deposit erosion to wet weather pollutant loads in combined sewer systems.

PubMed

Gasperi, J; Gromaire, M C; Kafi, M; Moilleron, R; Chebbo, G

2010-12-01

An observatory of urban pollutants was created in Paris for the purpose of assessing the dynamics of wastewater and wet weather flow (WW and WWF) pollutant loads within combined sewers. This observatory is composed of six urban catchments, covering land areas ranging in size from 42 ha to 2581 ha. For a wide array of parameters including total suspended solids (TSS), chemical and biochemical oxygen demand (COD and BOD(5)), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), heavy metals (Cu and Zn) and polycyclic aromatic hydrocarbons (PAHs), this article is intended to evaluate the contributions of wastewater, runoff and in-sewer processes to WWF pollutant loads through the use of an entry-exit mass balance approach. To achieve this objective, a total of 16 rain events were sampled on these sites between May 2003 and February 2006. This study has confirmed that at the considered catchment scale (i.e. from 42 ha to 2581 ha) the production and transfer processes associated with WWF pollutant loads do not vary with basin scale. Entry-exit chemical mass balances over all catchments and for a large number of rain events indicate that wastewater constitutes the main source of organic and nitrogenous pollution, while runoff is the predominant source of Zn. For Cu, PAHs and TSS, the calculation underscores the major role played by in-sewer processes, specifically by sediment erosion, as a source of WWF pollution. A significant loss of dissolved metals was also observed during their transfer within the sewer network, likely as a consequence of the adsorption of dissolved metals on TSS and/or on sewer deposits. Moreover, the nature of eroded particles was examined and compared to the various sewer deposits. This comparison has highlighted that such particles exhibit similar organic and PAH contents to those measured in the organic layer, thus suggesting that the deposit eroded during a wet weather period is organic and of a nature comparable to the organic layer. Despite the extent of initial field investigations, no organic deposit was observed to be present on sewer lines within the catchments, which implies that this organic deposit is probably present in another form or to be found elsewhere in the main trunks. Copyright © 2010 Elsevier Ltd. All rights reserved.

State waste discharge permit application: 200 Area Treated Effluent Disposal Facility (Project W-049H)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-08-01

As part of the original Hanford Federal Facility Agreement and Concent Order negotiations, US DOE, US EPA and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground to the Hanford Site are subject to permitting in the State Waste Discharge Permit Program (SWDP). This document constitutes the SWDP Application for the 200 Area TEDF stream which includes the following streams discharged into the area: Plutonium Finishing Plant waste water; 222-S laboratory Complex waste water; T Plant waste water; 284-W Power Plant waste water; PUREX chemical Sewer; B Plant chemical sewer, process condensate, steam condensate; 242-A-81more » Water Services waste water.« less
Superfund record of decision (EPA Region 4): Alabama Army Ammunition Plant, Area B soils operable unit, Childersburg, AL, November 14, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-03-01

This decision document presents the selected remedial action for the contaminated soils and sediments in Study Areas, 6, 7, and 21, and the Industrial Sewer System (ISS) in Study Areas 6, 7, and 10 within Area B at the Alabama Army Ammunition Plant (ALAAP), Childersburg, Alabama. The Area B Soils Operable Unit addresses the principal threats from soils and sediments in Study Areas 6, 7, and 21, and underground industrial sewer lines in Study Areas 6, 7, and 10. The soils and sediments and the industrial sewer lines are contaminated with explosives and lead.
Damage estimation of sewer pipe using subtitles of CCTV inspection video

NASA Astrophysics Data System (ADS)

Park, Kitae; Kim, Byeongcheol; Kim, Taeheon; Seo, Dongwoo

2017-04-01

Recent frequent occurrence of urban sinkhole serves as a momentum of the periodic inspection of sewer pipelines. Sewer inspection using a CCTV device needs a lot of time and efforts. Many of previous studies which reduce the laborious tasks are mainly interested in the developments of image processing S/W and exploring H/W. And there has been no attempt to find meaningful information from the existing CCTV images stored by the sewer maintenance manager. This study adopts a cross-correlation based image processing method and extracts sewer inspection device's location data from CCTV images. As a result of the analysis of location-time relation, it show strong correlation between device stand time and the sewer damages. In case of using this method to investigate sewer inspection CCTV images, it will save the investigator's efforts and improve sewer maintenance efficiency and reliability.
One-dimensional modelling of the interactions between heavy rainfall-runoff in an urban area and flooding flows from sewer networks and rivers.

PubMed

Kouyi, G Lipeme; Fraisse, D; Rivière, N; Guinot, V; Chocat, B

2009-01-01

Many investigations have been carried out in order to develop models which allow the linking of complex physical processes involved in urban flooding. The modelling of the interactions between overland flows on streets and flooding flows from rivers and sewer networks is one of the main objectives of recent and current research programs in hydraulics and urban hydrology. This paper outlines the original one-dimensional linking of heavy rainfall-runoff in urban areas and flooding flows from rivers and sewer networks under the RIVES project framework (Estimation of Scenario and Risks of Urban Floods). The first part of the paper highlights the capacity of Canoe software to simulate the street flows. In the second part, we show the original method of connection which enables the modelling of interactions between processes in urban flooding. Comparisons between simulated results and the results of Despotovic et al. or Gomez & Mur show a good agreement for the calibrated one-dimensional connection model. The connection operates likes a manhole with the orifice/weir coefficients used as calibration parameters. The influence of flooding flows from river was taken into account as a variable water depth boundary condition.
Modeling of wastewater quality in an urban area during festival and rainy days.

PubMed

Obaid, H A; Shahid, S; Basim, K N; Chelliapan, S

2015-01-01

Water pollution during festival periods is a major problem in all festival cities across the world. Reliable prediction of water pollution is essential in festival cities for sewer and wastewater management in order to ensure public health and a clean environment. This article aims to model the biological oxygen demand (BOD(5)), and total suspended solids (TSS) parameters in wastewater in the sewer networks of Karbala city center during festival and rainy days using structural equation modeling and multiple linear regression analysis methods. For this purpose, 34 years (1980-2014) of rainfall, temperature and sewer flow data during festival periods in the study area were collected, processed, and employed. The results show that the TSS concentration increases by 26-46 mg/l while BOD(5) concentration rises by 9-19 mg/l for an increase of rainfall by 1 mm during festival periods. It was also found that BOD(5) concentration rises by 4-17 mg/l for each increase of 10,000 population.
MANAGEMENT AND CONTROL OF COMBINED SEWER OVERFLOWS

EPA Science Inventory

The paper gives a basic overview of the U.S. government's involvements in developing countermeasures for the abatement of combined sewer overflow pollution. batement or prevention of pollution stormwater runoff and combined sewer overflows is one of the most challenging areas in ...
Coupled 1-D sewer and street networks and 2-D flooding model to rapidly evaluate surface inundation

NASA Astrophysics Data System (ADS)

Kao, Hong-Ming; Hsu, Hao-Ming

2017-04-01

Flash floods have occurred frequently in the urban areas around the world and cause the infrastructure and people living to expose continuously in the high risk level of pluvial flooding. According to historical surveys, the major reasons of severe surface inundations in the urban areas can be attributed to heavy rainfall in the short time and/or drainage system failure. In order to obtain real-time flood forecasting with high accuracy and less uncertainty, an appropriate system for predicting floods is necessary. For the reason, this study coupled 1-D sewer and street networks and 2-D flooding model as an operational modelling system for rapidly evaluating surface inundation. The proposed system is constructed by three significant components: (1) all the rainfall-runoff of a sub-catchment collected via gullies is simulated by the RUNOFF module of the Storm Water Management Model (SWMM); (2) and directly drained to the 1-D sewer and street networks via manholes as inflow discharges to conduct flow routing by using the EXTRAN module of SWMM; (3) after the 1-D simulations, the surcharges from manholes are considered as point sources in 2-D overland flow simulations that are executed by the WASH123D model. It can thus be used for urban flood modelling that reflects the rainfall-runoff processes, and the dynamic flow interactions between the storm sewer system and the ground surface in urban areas. In the present study, we adopted the Huwei Science and Technology Park, located in the south-western part of Taiwan, as the demonstration area because of its high industrial values. The region has an area about 1 km2 with approximately 1 km in both length and width. It is as isolated urban drainage area in which there is a complete sewer system that collects the runoff and drains to the detention pond. Based on the simulated results, the proposed modelling system was found that the simulated floods fit to the survey records because the physical rainfall-runoff phenomena in urban environment were better reflected. Keywords: SWMM, WASH123D, surface inundation, real-time.
Association between Gastrointestinal Illness and Precipitation in Areas Impacted by Combined Sewer Systems: Utilizing a Distributed Lag Model

EPA Science Inventory

Combined sewer systems collect rainwater runoff, sewage, and industrial wastewater for transit to treatment facilities. With heavy precipitation, volumes can exceed capacity of treatment facilities, and wastewater discharges directly to receiving waters. These combined sewer over...
Searching for storm water inflows in foul sewers using fibre-optic distributed temperature sensing.

PubMed

Schilperoort, Rémy; Hoppe, Holger; de Haan, Cornelis; Langeveld, Jeroen

2013-01-01

A major drawback of separate sewer systems is the occurrence of illicit connections: unintended sewer cross-connections that connect foul water outlets from residential or industrial premises to the storm water system and/or storm water outlets to the foul sewer system. The amount of unwanted storm water in foul sewer systems can be significant, resulting in a number of detrimental effects on the performance of the wastewater system. Efficient removal of storm water inflows into foul sewers requires knowledge of the exact locations of the inflows. This paper presents the use of distributed temperature sensing (DTS) monitoring data to localize illicit storm water inflows into foul sewer systems. Data results from two monitoring campaigns in foul sewer systems in the Netherlands and Germany are presented. For both areas a number of storm water inflow locations can be derived from the data. Storm water inflow can only be detected as long as the temperature of this inflow differs from the in-sewer temperatures prior to the event. Also, the in-sewer propagation of storm and wastewater can be monitored, enabling a detailed view on advection.
Changes in water quality parameters due to in-sewer processes.

PubMed

Boxall, J; Shepherd, W; Guymer, I; Fox, K

2003-01-01

Combined sewer systems contain a large number of organic and inorganic pollutants from both domestic and industrial sources. These pollutants are often retained within the combined sewer system for significant lengths of time before entering sewage treatment works, or being spilt to a watercourse via a combined sewer overflow (CSO) during storm conditions. Currently little knowledge exists concerning the effects of in sewer processes on pollutants. Understanding of in-sewer processes is important for the effective and efficient design of treatment works and CSO chambers and for impact assessments on receiving waters. A series of studies covering storm and dry weather flow conditions were undertaken with the aim of investigating the nature of in-sewer processes. These studies consisted of marking a body of water with a fluorescent tracer. The tracer was then monitored at a series of downstream sites, and discrete samples collected from the body of water as it progressed through the sewer. The samples were analysed for water quality parameters and these results investigated in tandem with the detailed hydraulic information gained through the tracer studies. The results highlight the hydraulic differences between storm and dry weather conditions such as increased travel times and mixing under storm conditions. The Advection Dispersion Equation (ADE) and Aggregated Dead Zone (ADZ) model parameters have been quantified for the tracer data. The ADE mixing coefficient is shown to increase by an order of magnitude for storm conditions. The ADZ dispersive fraction parameter is shown to be approximately constant with flow. Chemical reactions and decay within the sewer system were found to be consistent with oxygen limitation.
Hydrologic monitoring for Chicago’s Sustainable Streetscapes Program

USGS Publications Warehouse

Duncker, James J.; Morrow, William S.

2016-04-05

The Chicago Department of Transportation’s Sustainable Streetscapes Program is an innovative program that strives to convert Chicago’s neighborhood commercial areas, riverwalks, and bicycle facilities into active, attractive places for Chicagoans to live, work, and play. The objective of each project is to create flourishing public places while improving the ability of infrastructure to support dense urban living. The U.S. Geological Survey (USGS), in cooperation with the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC), and the Chicago Department of Transportation (CDOT), is monitoring the pre- and postconstruction hydrologic characteristics of an urban corridor on the south side of Chicago that is being renovated using sustainable streetscapes technology.The CDOT Sustainable Streetscapes Program utilizes urban stormwater best-management practices (BMPs) to reduce the storm runoff to the local combined sewer system. The urban stormwater BMPs include permeable pavement, bioswales, infiltration basins, and planters. The urban stormwater BMPs are designed to capture the first flush of storm runoff through features that enhance the infiltration of stormwater runoff to shallow groundwater.The hydrology of the Sustainable Streetscapes Program area is being monitored to evaluate the impacts and effectiveness of the urban stormwater BMP’s. Continuous monitoring of rainfall, sewer flows, stormwater runoff, soil moisture, and groundwater levels will give engineers and scientists measured data to define baseline pre- and postconstruction conditions for the evaluation of the BMPs.Three tipping-bucket rain gages are located along the project corridor. The data provide information on the intensity and volume of rainfall. Rainfall can be highly variable even over a small area like the project corridor.Continuous recording meters are located at specific locations in the combined sewers to record water level and flow during both dry weather (mostly sanitary flow) and wet weather conditions (stormwater runoff in addition to the sanitary flow). Sanitary flow is the largest source of flow in the combined sewers during dry weather, and stormwater runoff and sanitary flow combine during wet weather. The sewer flow data allow engineers and scientists to calculate total runoff volume for selected storm events.Wells are located within the project corridor to record water levels and help determine the direction of movement of groundwater in response to rainfall and snowmelt. In urban settings with aging sewer systems, groundwater can seep into the sewers or combined sewage can seep from the sewers into the local groundwater system. The groundwater data are also important in evaluating the overall impacts of increased infiltration resulting from BMPs.Data from wells show the relative water levels of shallow groundwater, water levels in the combined sewer system, and nearby surface-water channels within the project corridor. In some aging urban sewer systems, the local combined sewer system lies below the water table and receives substantial amounts of groundwater inflow, which can significantly reduce the amount of additional water the sewer system can accept.The bioswale along the south side of West Cermak Road near South Throop Street functions to infiltrate stormwater runoff from the road. Stormwater on the road surface initially drains to the curb and then flows along the curb until it reaches a curb cut-out. Materials within the bioswale allow stormwater to infiltrate and reduce the load to the combined sewer.A common feature in urban areas are curbside catch basins that collect stormwater runoff from paved streets. Stormwater drains first to the curb and then flows along the curb to the catch basin. Lateral sewer pipe connects the catch basin to the combined sewer beneath the street. The use of permeable pavers along the curbs in the project study reach let stormwater infiltrate before it reaches the curb, thus reducing the amount of stormwater draining to the combined sewers.Water-level data from catch basins in the project study area show the effects of permeable pavers in reducing the stormwater drainage to the combined sewers.
Sewer solids separation by sedimentation--the problem of modeling, validation and transferability.

PubMed

Kutzner, R; Brombach, H; Geiger, W F

2007-01-01

Sedimentation of sewer solids in tanks, ponds and similar devices is the most relevant process for the treatment of stormwater and combined sewer overflows in urban collecting systems. In the past a lot of research work was done to develop deterministic models for the description of this separation process. But these modern models are not commonly accepted in Germany until today. Water Authorities are sceptical with regard to model validation and transferability. Within this paper it is checked whether this scepticism is reasonable. A framework-proposal for the validation of mathematical models with zero or one dimensional spatial resolution for particle separation processes for stormwater and combined sewer overflow treatment is presented. This proposal was applied to publications of repute on sewer solids separation by sedimentation. The result was that none of the investigated models described in literature passed the validation entirely. There is an urgent need for future research in sewer solids sedimentation and remobilization!
Cost Comparison of Conventional Gray Combined Sewer Overflow Control Infrastructure versus a Green/Gray Combination

EPA Science Inventory

This paper outlines a life-cycle cost analysis comparing a green (rain gardens) and gray (tunnels) infrastructure combination to a gray-only option to control combined sewer overflow in the Turkey Creek Combined Sewer Overflow Basin, in Kansas City, MO. The plan area of this Bas...
Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas With and Without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007

EPA Science Inventory

Background: Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff discharge into waterbodies potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme pre...
Modelling of sedimentation and remobilization in in-line storage sewers for stormwater treatment.

PubMed

Frehmann, T; Flores, C; Luekewille, F; Mietzel, T; Spengler, B; Geiger, W F

2005-01-01

A special arrangement of combined sewer overflow tanks is the in-line storage sewer with downstream discharge (ISS-down). This layout has the advantage that, besides the sewer system, no other structures are required for stormwater treatment. The verification of the efficiency with respect to the processes of sedimentation and remobilization of sediment within the in-line storage sewer with downstream discharge is carried out in a combination of a field and a pilot plant study. The model study was carried out using a pilot plant model scaled 1:13. The following is intended to present some results of the pilot plant study and the mathematical empirical modelling of the sedimentation and remobilization process.
The effect of inclusion of inlets in dual drainage modelling

NASA Astrophysics Data System (ADS)

Chang, Tsang-Jung; Wang, Chia-Ho; Chen, Albert S.; Djordjević, Slobodan

2018-04-01

In coupled sewer and surface flood modelling approaches, the flow process in gullies is often ignored although the overland flow is drained to sewer network via inlets and gullies. Therefore, the flow entering inlets is transferred to the sewer network immediately, which may lead to a different flood estimation than the reality. In this paper, we compared two modelling approach with and without considering the flow processes in gullies in the coupled sewer and surface modelling. Three historical flood events were adopted for model calibration and validation. The results showed that the inclusion of flow process in gullies can further improve the accuracy of urban flood modelling.
Characterization of runoff from various urban catchments at different spatial scales in Beijing, China.

PubMed

Zhang, W; Che, W; Liu, D K; Gan, Y P; Lv, F F

2012-01-01

In order to investigate the characterization of runoff in storm sewer from various urban catchments, three monitoring systems at different spatial scales have been installed separately. They have been held since July 2010 in urban area of Beijing (China). The monitoring data revealed that chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), and NH(3)-N values significantly exceed the Class V surface water quality standard developed by Ministry of Environmental Protection of the People's Republic of China (MEP). A surface solids buildup and wash off model for small watershed was adopted to analyze and discuss the process of a runoff pollutant discharge. More than a half of pollutant parameters presented a good fit to the model. However, a slightly worse-fit to the wash off model appeared in less than half of the data. Due to the influence of sewer sediments, sewer system characteristics, catchment characteristics, and other reasons, first flush was seldom observed in storm sewer runoff from these three survey areas. Meanwhile, the correlation between TSS and any other pollutant was analyzed according to cumulative load of pollutants in runoff events. An event mean concentrations (EMCs) approach was adopted to quantify the pollution of runoff. EMCs of various pollutants in storm sewer runoff between different rainfall events were slightly higher than the typical values observed in similar areas at home and abroad, according to other studies reported in literature. Based on quantitative analysis, it can be concluded that urban non-point source pollution is recognized as the major causes of quality deterioration in the receiving water bodies. This is after the point source pollution has been controlled substantially in Beijing. An integrated strategy, which combines centralized and decentralized control, along with the conditions of meteorology, hydrology, urban planning, existing drainage system, etc., will be an effective and economic approach to urban runoff pollution control.
40 CFR 35.2024 - Combined sewer overflows.

Code of Federal Regulations, 2010 CFR

2010-07-01

... project priority list, it addresses impaired uses in priority water quality areas which are due to the... must demonstrate to the Administrator that the water quality goals of the Act will not be achieved... priority water quality areas in marine bays and estuaries due to the impacts of combined sewer overflows...
RATES OF GASTROINTESTINAL ILLNESS AMONG AREAS IMPACTED BY COMBINED SEWER FACILITIES: ANALYSIS OF MASSACHUSETTS DATA, 2003-2007

EPA Science Inventory

Previous studies have reported a temporal association between heavy rainfall and gastrointestinal infection (GI). Combined sewer systems (CSSs), which are present in many urban areas in the US, were designed to collect rainwater runoff, domestic sewage, and industrial wastewater ...
Analysis of Changes in Ground-Water Levels in a Sewered and an Unsewered Area of Nassau County, Long Island, New York.

PubMed

Sulam, Dennis J

1979-09-01

From the 195O's to the early 1970's expansion of sanitary sewerage in southwest Nassau County contributed to progressive declines in ground-water levels. Since the early 197O's, however, 10 years after the area was fully sewered, water levels have not declined significantly, which suggests that the water table may have reached a new equilibrium position. Double-mass-curve analyses show that during 1953-76 the average weighted ground-water levels in a 32-square-mile (83-square-kilometer) part of the sewered area declined 12.2 feet (3.73 meters) more than those in the unsewered area to the east. However, by 1973 this decline was 13.5 feet (4.1 meters). Finite-difference digital-model results indicate that 3.6 feet (1.1 meters) of the relative 1953-76 decline was due to pumping in adjacent Queens County and that most of the remaining decline was a result of sewerage. Streamflow within the sewered area decreased in response to the lowered ground-water levels, and ground-water levels in the adjacent unsewered area were also lowered because of the sewerage.

Methane emission from sewers.

PubMed

Liu, Yiwen; Ni, Bing-Jie; Sharma, Keshab R; Yuan, Zhiguo

2015-08-15

Recent studies have shown that sewer systems produce and emit a significant amount of methane. Methanogens produce methane under anaerobic conditions in sewer biofilms and sediments, and the stratification of methanogens and sulfate-reducing bacteria may explain the simultaneous production of methane and sulfide in sewers. No significant methane sinks or methanotrophic activities have been identified in sewers to date. Therefore, most of the methane would be emitted at the interface between sewage and atmosphere in gravity sewers, pumping stations, and inlets of wastewater treatment plants, although oxidation of methane in the aeration basin of a wastewater treatment plant has been reported recently. Online measurements have also revealed highly dynamic temporal and spatial variations in methane production caused by factors such as hydraulic retention time, area-to-volume ratio, temperature, and concentration of organic matter in sewage. Both mechanistic and empirical models have been proposed to predict methane production in sewers. Due to the sensitivity of methanogens to environmental conditions, most of the chemicals effective in controlling sulfide in sewers also suppress or diminish methane production. In this paper, we review the recent studies on methane emission from sewers, including the production mechanisms, quantification, modeling, and mitigation. Copyright © 2015 Elsevier B.V. All rights reserved.
Estimation of sediments in urban drainage areas and relation analysis between sediments and inundation risk using GIS.

PubMed

Moojong, Park; Hwandon, Jun; Minchul, Shin

2008-01-01

Sediments entering the sewer in urban areas reduce the conveyance in sewer pipes, which increases inundation risk. To estimate sediment yields, individual landuse areas in each sub-basin should be obtained. However, because of the complex nature of an urban area, this is almost impossible to obtain manually. Thus, a methodology to obtain individual landuse areas for each sub-basin has been suggested for estimating sediment yields. Using GIS, an urban area is divided into sub-basins with respect to the sewer layout, with the area of individual landuse estimated for each sub-basin. The sediment yield per unit area for each sub-basin is then calculated. The suggested method was applied to the GunJa basin in Seoul. For a relation analysis between sediments and inundation risk, sub-basins were ordered by the sediment yields per unit area and compared with historical inundation areas. From this analysis, sub-basins with higher order were found to match the historical inundation areas. Copyright IWA Publishing 2008.
Long-term impacts on sewers following food waste disposer installation in housing areas.

PubMed

Mattsson, Jonathan; Hedström, Annelie; Viklander, Maria

2014-01-01

To increase biogas generation and decrease vehicle transportation of solid waste, the integration of food waste disposers (FWDs) into the wastewater system has been proposed. However, concerns have been raised about the long-term impact of the additional load of the FWDs on sewer systems. To examine the said impact, this study has used closed-circuit television inspection techniques to evaluate the status of 181 concrete pipes serving single family housing areas with a diameter of 225 mm, ranging from a 100% connection rate of households with an FWD to none. A minor study was also performed on a multi-family housing area, where mainly plastic pipes (200 mm) were used. The extent and distribution of deposits related to the ratio of FWDs, inclination and pipe sagging (backfalls) were ascertained by using linear regression and analysis of variance. The results showed that FWDs have had an impact on the level of deposits in the sewer, but this has, in turn, been of minor significance. With a high connection rate of FWDs upstream of a pipe, the extent of the total level of deposits, as well as finer sediments, was statistically determined to be greater. However, the majority of the deposits were observed to be small, which would suggest the impact of FWDs on sewer performance to be minor. As food waste not compatible with the FWD was seen in the sewers, educational campaigns could be beneficial to further lower the risks of sewer blocking.
Identification of in-sewer sources of organic solids contributing to combined sewer overflows.

PubMed

Ahyerre, M; Chebbo, G

2002-09-01

Previous research has shown that combined sewer systems are the main source of particle and organic pollution during rainfall events contributing to combined sewer overflow. The aim of this article is to identify in an urban catchment area called "Le Marais", in the center of Paris, the types of sediments that are eroded and contribute to the pollution of combined sewer overflow. Three sediment types are considered: granular material found in the inverts of pipes, organic biofilms and organic sediment at the water bed interface, identified as an immobile layer in the "Le Marais" catchment area. The method used consist, firstly, of sampling and assessing the organic pollutant loads and metallic loads of the particles in each type of sediment. Then, the mass of each type of sediment is assessed. The mass and the characteristics of each type of sediment is finally compared to the mass and characteristics of the particles eroded in the catchment area, estimated by mass balances, in order to find the source of eroded particles. The only identified type of deposit that can contribute to combined sewer overflows is the organic layer. Indeed, the solids of this layer have mean and metallic loads that are of the same order of magnitude as the eroded particles. Moreover, the mass of the organic layer considered over different time scales is of the same order of magnitude as the eroded masses during rainfall events and an erosion experiment showed that the organic layer is actually eroded.
Forensic applications of nitrogen and oxygen isotopes in tracing nitrate sources in urban environments

USGS Publications Warehouse

Silva, S.R.; Ging, P.B.; Lee, R.W.; Ebbert, J.C.; Tesoriero, A.J.; Inkpen, E.L.

2002-01-01

Ground and surface waters in urban areas are susceptible to nitrate contamination from septic systems, leaking sewer lines, and fertilizer applications. Source identification is a primary step toward a successful remediation plan in affected areas. In this respect, nitrogen and oxygen isotope ratios of nitrate, in conjunction with hydrologic data and water chemistry, have proven valuable in urban studies from Austin, Texas, and Tacoma, Washington. In Austin, stream water was sampled during stremflow and baseflow conditions to assess surface and subsurface sources of nitrate, respectively. In Tacoma, well waters were sampled in adjacent sewered and un-sewered areas to determine if locally high nitrate concentrations were caused by septic systems in the un-sewered areas. In both studies, sewage was identified as a nitrate source and mixing between sewage and other sources of nitrate was apparent. In addition to source identification, combined nitrogen and oxygen isotopes were important in determining the significance of denitrification, which can complicate source assessment by reducing nitrate concentrations and increasing ??15N values. The two studies illustrate the value of nitrogen and oxygen isotopes of nitrate for forensic applications in urban areas. ?? Published by Elsevier Science Ltd. on behalf of AEHS.
[Transport and sources of runoff pollution from urban area with combined sewer system].

PubMed

Li, Li-Qing; Yin, Cheng-Qing

2009-02-15

Sampling and monitoring of runoff and sewage water in Wuhan urban area with combined sewer system were carried out during the period from 2003 to 2006, to study the transport and sources of runoff pollution at the catchment scale coupled with environmental geochemistry method. The results showed a change in quality between the runoff entering the sewer network and the combined storm water flow at the sewer's outlet. A significant increase was observed in the concentrations of total suspended solids (TSS), volatile suspended solids (VSS), COD, TN, and TP, and in the proportion of COD linked to particles. During the runoff production and transport, the concentrations of TSS and COD increased from 18.7 mg/L and 37.0 mg/L in roof runoff, to 225.3 mg/L and 176.5 mg/L in street runoff, and to 449.7 mg/L and 359.9 mg/L in combined storm water flow, respectively. The proportion of COD linked to particles was increased by 18%. In addition, the total phosphorus (P) and iron (Fe) contents in urban ground dust, storm drain sediment, sewage sewer sediment and combined sewer sediment were measured to identify the potential sources of suspended solids in the combined flow. The urban ground dust andstorm drain sediment wererich in Fe, whereas the sewage sewer sediment was rich in P. The P/Fe ratios in these groups were significantly distinct and able to differentiate them. A calculation of the two storm events based on the P/Fe rations showed that 56% +/- 26% of suspended solids in combined flow came from urban ground and storm drain. The rest wer e originated from the sewage sewer sediments which deposited in combined sewer on the dry weather days and were eroded on the wet weather days. The combined sewer network not only acts as a transport system, but also constitutes a physicochemical reactor that degrades the quality of urban water. Reducing the in-sewer pollution stocks would effectively control urban runoff pollution.
Effect of inlet modelling on surface drainage in coupled urban flood simulation

NASA Astrophysics Data System (ADS)

Jang, Jiun-Huei; Chang, Tien-Hao; Chen, Wei-Bo

2018-07-01

For a highly developed urban area with complete drainage systems, flood simulation is necessary for describing the flow dynamics from rainfall, to surface runoff, and to sewer flow. In this study, a coupled flood model based on diffusion wave equations was proposed to simulate one-dimensional sewer flow and two-dimensional overland flow simultaneously. The overland flow model provides details on the rainfall-runoff process to estimate the excess runoff that enters the sewer system through street inlets for sewer flow routing. Three types of inlet modelling are considered in this study, including the manhole-based approach that ignores the street inlets by draining surface water directly into manholes, the inlet-manhole approach that drains surface water into manholes that are each connected to multiple inlets, and the inlet-node approach that drains surface water into sewer nodes that are connected to individual inlets. The simulation results were compared with a high-intensity rainstorm event that occurred in 2015 in Taipei City. In the verification of the maximum flood extent, the two approaches that considered street inlets performed considerably better than that without street inlets. When considering the aforementioned models in terms of temporal flood variation, using manholes as receivers leads to an overall inefficient draining of the surface water either by the manhole-based approach or by the inlet-manhole approach. Using the inlet-node approach is more reasonable than using the inlet-manhole approach because the inlet-node approach greatly reduces the fluctuation of the sewer water level. The inlet-node approach is more efficient in draining surface water by reducing flood volume by 13% compared with the inlet-manhole approach and by 41% compared with the manhole-based approach. The results show that inlet modeling has a strong influence on drainage efficiency in coupled flood simulation.
Evaluation of the Effectiveness of Five Odor Reducing Agents for Sewer System Odors Using an On-Line Total Reduced Sulfur Analyzer

PubMed Central

Choi, Il; Lee, Hyunjoo; Shin, Joungdu; Kim, Hyunook

2012-01-01

Sewer odors have been a concern to citizens of the Metropolitan Seoul region, which has installed combined sewer systems (CSSs) in 86% of its area. Although a variety of odorants are released from sewers, volatile sulfur compounds (VSCs) have been recognized as major ones. A number of technologies have been proposed to monitor or control odors from sewers. One of the most popular strategies adopted for the control of sewage odor is by applying a commercial odor-reducing agent into the sewer. In this study, the effectiveness of five different commercial odor-reducing agents (i.e., an odor masking agent, an alkaline solution, two microbial agents, and a chemical oxidant) was evaluated by continuously monitoring VSCs released from the sewer with an on-line total reduced sulfur (TRS) analyzer before and after each agent was sprayed into CSSs at five different locations of the city. In short, when the effectiveness of odor treatment was tested in the sewer system using five commercial odor reducing treatments, only the chemical oxidant was good enough to reduce the odor in terms of TRS levels measured before and after the application (p < 0.01). PMID:23223148
EXFILTRATION IN SEWER SYSTEMS

EPA Science Inventory

This study focused on the quantification of leakage of sanitary and industrial sewage from sanitary sewer pipes on a national basis. The method for estimating exfiltration amounts utilized groundwater talbe information to identify areas of the country where the hydraulic gradient...
Transformation and Sorption of Illicit Drug Biomarkers in Sewer Systems: Understanding the Role of Suspended Solids in Raw Wastewater.

PubMed

Ramin, Pedram; Libonati Brock, Andreas; Polesel, Fabio; Causanilles, Ana; Emke, Erik; de Voogt, Pim; Plósz, Benedek Gy

2016-12-20

Sewer pipelines, although primarily designed for sewage transport, can also be considered as bioreactors. In-sewer processes may lead to significant variations of chemical loadings from source release points to the treatment plant influent. In this study, we assessed in-sewer utilization of growth substrates (primary metabolic processes) and transformation of illicit drug biomarkers (secondary metabolic processes) by suspended biomass. Sixteen drug biomarkers were targeted, including mephedrone, methadone, cocaine, heroin, codeine, and tetrahydrocannabinol (THC) and their major human metabolites. Batch experiments were performed under aerobic and anaerobic conditions using raw wastewater. Abiotic biomarker transformation and partitioning to suspended solids and reactor wall were separately investigated under both redox conditions. A process model was identified by combining and extending the Wastewater Aerobic/anaerobic Transformations in Sewers (WATS) model and Activated Sludge Model for Xenobiotics (ASM-X). Kinetic and stoichiometric model parameters were estimated using experimental data via the Bayesian optimization method DREAM (ZS) . Results suggest that biomarker transformation significantly differs from aerobic to anaerobic conditions, and abiotic conversion is the dominant mechanism for many of the selected substances. Notably, an explicit description of biomass growth during batch experiments was crucial to avoid significant overestimation (up to 385%) of aerobic biotransformation rate constants. Predictions of in-sewer transformation provided here can reduce the uncertainty in the estimation of drug consumption as part of wastewater-based epidemiological studies.
Distributed simulation of long-term hydrological processes in a medium-sized periurban catchment under changing land use and rainwater management.

NASA Astrophysics Data System (ADS)

Labbas, Mériem; Braud, Isabelle; Branger, Flora; Kralisch, Sven

2013-04-01

Growing urbanization and related anthropogenic processes have a high potential to influence hydrological process dynamics. Typical consequences are an increase of surface imperviousness and modifications of water flow paths due to artificial channels and barriers (combined and separated system, sewer overflow device, roads, ditches, etc.). Periurban catchments, at the edge of large cities, are especially affected by fast anthropogenic modifications. They usually consist of a combination of natural areas, rural areas with dispersed settlements and urban areas mostly covered by built zones and spots of natural surfaces. In the context of the European Water Framework Directive (2000) and the Floods Directive (2007), integrated and sustainable solutions are needed to reduce flooding risks and river pollution at the scale of urban conglomerations or whole catchments. Their thorough management requires models able to assess the vulnerability of the territory and to compare the impact of different rainwater management options and planning issues. To address this question, we propose a methodology based on a multi-scale distributed hydrological modelling approach. It aims at quantifying the impact of ongoing urbanization and stormwater management on the long-term hydrological cycle in medium-sized periurban watershed. This method focuses on the understanding and formalization of dominant periurban hydrological processes from small scales (few ha to few km2) to larger scales (few hundred km2). The main objectives are to 1) simulate both urban and rural hydrological processes and 2) test the effects of different long-term land use and water management scenarios. The method relies on several tools and data: a distributed hydrological model adapted to the characteristics of periurban areas, land use and land cover maps from different dates (past, present, future) and information about rainwater management collected from local authorities. For the application of the method, the medium-scaled catchment of Yzeron (France) is chosen. It is subjected to a fast progression of urbanization since the eighties and has been monitored for a long time period. The fully-distributed hydrological model J2000, available through the JAMS modelling framework, was found appropriate to simulate the water balance of the Yzeron catchment at a daily time step. However, it was not designed especially for periurban areas, so its structure and parameters are under adaptation. Firstly, as hydrological responses in urban areas are quicker than in rural areas, a sub-daily time step is necessary to improve the simulation of periurban hydrological processes. Therefore, J2000 was adapted to be run at a hourly time step. Secondly, in order to better take into account rainwater management, an explicit representation of sewer networks is implemented in the J2000 model whose periurban version is called J2000P. It receives urban rainwater coming from impervious surfaces connected to a combined sewer system and delivers this water to the treatment plant or directly to the river in case of sewer overflow device outflows. We will present the impact of these modifications on the simulated hydrological regime.
Impervious surfaces and sewer pipe effects on stormwater runoff temperature

NASA Astrophysics Data System (ADS)

Sabouri, F.; Gharabaghi, B.; Mahboubi, A. A.; McBean, E. A.

2013-10-01

The warming effect of the impervious surfaces in urban catchment areas and the cooling effect of underground storm sewer pipes on stormwater runoff temperature are assessed. Four urban residential catchment areas in the Cities of Guelph and Kitchener, Ontario, Canada were evaluated using a combination of runoff monitoring and modelling. The stormwater level and water temperature were monitored at 10 min interval at the inlet of the stormwater management ponds for three summers 2009, 2010 and 2011. The warming effect of the ponds is also studied, however discussed in detail in a separate paper. An artificial neural network (ANN) model for stormwater temperature was trained and validated using monitoring data. Stormwater runoff temperature was most sensitive to event mean temperature of the rainfall (EMTR) with a normalized sensitivity coefficient (Sn) of 1.257. Subsequent levels of sensitivity corresponded to the longest sewer pipe length (LPL), maximum rainfall intensity (MI), percent impervious cover (IMP), rainfall depth (R), initial asphalt temperature (AspT), pipe network density (PND), and rainfall duration (D), respectively. Percent impervious cover of the catchment area (IMP) was the key parameter that represented the warming effect of the paved surfaces; sensitivity analysis showed IMP increase from 20% to 50% resulted in runoff temperature increase by 3 °C. The longest storm sewer pipe length (LPL) and the storm sewer pipe network density (PND) are the two key parameters that control the cooling effect of the underground sewer system; sensitivity analysis showed LPL increase from 345 to 966 m, resulted in runoff temperature drop by 2.5 °C.
D.C. Municipal Separate Storm Sewer System (MS4)

EPA Pesticide Factsheets

This permit covers all areas within the jurisdictional boundary of the District of Columbia served by, or otherwise contributing to discharges from, the Municipal Separate Storm Sewer System (MS4) owned or operated by the District of Columbia.
Assessment of erosion and sedimentation dynamic in a combined sewer network using online turbidity monitoring.

PubMed

Bersinger, T; Le Hécho, I; Bareille, G; Pigot, T

2015-01-01

Eroded sewer sediments are a significant source of organic matter discharge by combined sewer overflows. Many authors have studied the erosion and sedimentation processes at the scale of a section of sewer pipe and over short time periods. The objective of this study was to assess these processes at the scale of an entire sewer network and over 1 month, to understand whether phenomena observed on a small scale of space and time are still valid on a larger scale. To achieve this objective the continuous monitoring of turbidity was used. First, the study of successive rain events allows observation of the reduction of the available sediment and highlights the widely different erosion resistance for the different sediment layers. Secondly, calculation of daily chemical oxygen demand (COD) fluxes during the entire month was performed showing that sediment storage in the sewer pipe after a rain period is important and stops after 5 days. Nevertheless, during rainfall events, the eroded fluxes are more important than the whole sewer sediment accumulated during a dry weather period. This means that the COD fluxes promoted by runoff are substantial. This work confirms, with online monitoring, most of the conclusions from other studies on a smaller scale.
Effect of temperature on anoxic sulfide oxidation and denitrification in the bulk wastewater phase of sewer networks.

PubMed

Mathioudakis, V L; Aivasidis, A

2009-01-01

Artificial dosage of nitrate in sewer networks is considered as one of the most effective methods for odor and corrosion control. However, there is limited knowledge on the effect of temperature on the transformations that takes place during anoxic conditions. Thus, two groups of batch experiments were conducted to gain insight in the involved processes in bulk phase of a septic municipal wastewater. It can be concluded that sewer denitrification, in bulk phase, can be simplified in three stages. According to the experimental results, nitrate or nitrite is utilized for autotrophic denitrification with sulfide, while heterotrophic utilization is initiated after the completion of anoxic sulfide oxidation. Moreover, temperature is proved to have a significant impact on sewer denitrification kinetic profile, as it determines the extent of temporal nitrite accumulation. The temperature coefficient of each anoxic process, including sulfide oxidation, nitrate utilization and denitrification/nitrite utilization is experimentally calculated and temperature dependent equations are developed, providing the rate of all anoxic processes in bulk phase of sewer wastewater, in any given temperature.
Vision-based system for the control and measurement of wastewater flow rate in sewer systems.

PubMed

Nguyen, L S; Schaeli, B; Sage, D; Kayal, S; Jeanbourquin, D; Barry, D A; Rossi, L

2009-01-01

Combined sewer overflows and stormwater discharges represent an important source of contamination to the environment. However, the harsh environment inside sewers and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. In the following, we present and evaluate an in situ system for the monitoring of water flow in sewers based on video images. This paper focuses on the measurement of the water level based on image-processing techniques. The developed image-based water level algorithms identify the wall/water interface from sewer images and measure its position with respect to real world coordinates. A web-based user interface and a 3-tier system architecture enable the remote configuration of the cameras and the image-processing algorithms. Images acquired and processed by our system were found to reliably measure water levels and thereby to provide crucial information leading to better understand particular hydraulic behaviors. In terms of robustness and accuracy, the water level algorithm provided equal or better results compared to traditional water level probes in three different in situ configurations.
Fecal-indicator bacteria in streams alonga gradient of residential development

USGS Publications Warehouse

Frenzel, Steven A.; Couvillion, Charles S.

2002-01-01

Fecal-indicator bacteria were sampled at 14 stream sites in Anchorage, Alaska, USA, as part of a study to determine the effects of urbanization on water quality. Population density in the subbasins sampled ranged from zero to 1,750 persons per square kilometer. Higher concentrations of fecal-coliform, E. coli, and enterococci bacteria were measured at the most urbanized sites. Although fecal-indicator bacteria concentrations were higher in summer than in winter, seasonal differences in bacteria concentrations generally were not significant. Areas served by sewer systems had significantly higher fecal-indicator bacteria concentrations than did areas served by septic systems. The areas served by sewer systems also had storm drains that discharged directly to the streams, whereas storm sewers were not present in the areas served by septic systems. Fecal-indicator bacteria concentrations were highly variable over a two-day period of stable streamflow, which may have implications for testing of compliance to water-quality standards.
Sewers as a source and sink of chlorinated-solvent groundwater contamination, Marine Corps Recruit Depot, Parris Island, South Carolina

USGS Publications Warehouse

Vroblesky, D.A.; Petkewich, M.D.; Lowery, M.A.; Landmeyer, J.E.

2011-01-01

Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater. The southern plume originates at a nearby, new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. The strong influence of sanitary sewers on source distribution and of storm sewers on plume orientation and discharge at this site indicates that groundwater-contamination investigators should consider the potential influence of sewer systems at their sites. ?? 2011, National Ground Water Association.
Simulation of floods caused by overloaded sewer systems: extensions of shallow-water equations

NASA Astrophysics Data System (ADS)

Hilden, Michael

2005-03-01

The outflow of water from a manhole onto a street is a typical flow problem within the simulation of floods in urban areas that are caused by overloaded sewer systems in the event of heavy rains. The reliable assessment of the flood risk for the connected houses requires accurate simulations of the water flow processes in the sewer system and in the street.The Navier-Stokes equations (NSEs) describe the free surface flow of the fluid water accurately, but since their numerical solution requires high CPU times and much memory, their application is not practical. However, their solutions for selected flow problems are applied as reference states to assess the results of other model approaches.The classical shallow-water equations (SWEs) require only fractions (factor 1/100) of the NSEs' computational effort. They assume hydrostatic pressure distribution, depth-averaged horizontal velocities and neglect vertical velocities. These shallow-water assumptions are not fulfilled for the outflow of water from a manhole onto the street. Accordingly, calculations show differences between NSEs and SWEs solutions.The SWEs are extended in order to assess the flood risks in urban areas reliably within applicable computational efforts. Separating vortex regions from the main flow and approximating vertical velocities to involve their contributions into a pressure correction yield suitable results.
Effects of sanitary sewers on ground-water levels and streams in Nassau and Suffolk Counties, New York; Part 2, development and application of southwest Suffolk County model

USGS Publications Warehouse

Buxton, H.T.; Reilly, T.E.

1985-01-01

By 1990, sanitary sewers in Nassau County Sewage Disposal Districts 2 and 3 and Suffolk County Southwest Sewer District will discharge to the ocean 140 cu ft of water/sec that would otherwise be returned to the groundwater system through septic tanks and similar systems. To evaluate the effects of this loss on groundwater levels and streamflow, the U.S. Geological Survey developed a groundwater flow model that couples a fine-scale subregional model to a regional model of larger scale. The regional model generates flux boundary conditions for the subregional model, and the subregional model provides detail in the area of concern. Results indicate that the water table will decline by as much as 8 ft along the Suffolk-Nassau county line, with effects decreasing eastward. Base flow is predicted to decrease by as much as 73% in a stream along the county line, but this effect will decrease to zero just east of the sewered area. This report is one of a series describing the predicted hydrologic effects of sewers in southern Nassau and southwest Suffolk Counties. (USGS)

A Bayesian network model to assess the public health risk associated with wet weather sewer overflows discharging into waterways.

PubMed

Goulding, R; Jayasuriya, N; Horan, E

2012-10-15

Overflows from sanitary sewers during wet weather, which occur when the hydraulic capacity of the sewer system is exceeded, are considered a potential threat to the ecological and public health of the waterways which receive these overflows. As a result, water retailers in Australia and internationally commit significant resources to manage and abate sewer overflows. However, whilst some studies have contributed to an increased understanding of the impacts and risks associated with these events, they are relatively few in number and there still is a general lack of knowledge in this area. A Bayesian network model to assess the public health risk associated with wet weather sewer overflows is presented in this paper. The Bayesian network approach is shown to provide significant benefits in the assessment of public health risks associated with wet weather sewer overflows. In particular, the ability for the model to account for the uncertainty inherent in sewer overflow events and subsequent impacts through the use of probabilities is a valuable function. In addition, the paper highlights the benefits of the probabilistic inference function of the Bayesian network in prioritising management options to minimise public health risks associated with sewer overflows. Copyright © 2012. Published by Elsevier Ltd.
Urban Runoff and Combined Sewer Overflow.

ERIC Educational Resources Information Center

Field, Richard; Gardner, Bradford B.

1978-01-01

Presents a literature review of wastewater treatment, covering publications of 1976-77. This review includes areas such as: (1) urban runoff quality and quantity; (2) urban hydrology; (3) management practices; and (4) combined sewer overflows. A list of 140 references is also presented. (HM)
Prioritizing sewer rehabilitation projects using AHP-PROMETHEE II ranking method.

PubMed

Kessili, Abdelhak; Benmamar, Saadia

2016-01-01

The aim of this paper is to develop a methodology for the prioritization of sewer rehabilitation projects for Algiers (Algeria) sewer networks to support the National Sanitation Office in its challenge to make decisions on prioritization of sewer rehabilitation projects. The methodology applies multiple-criteria decision making. The study includes 47 projects (collectors) and 12 criteria to evaluate them. These criteria represent the different issues considered in the prioritization of the projects, which are structural, hydraulic, environmental, financial, social and technical. The analytic hierarchy process (AHP) is used to determine weights of the criteria and the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE II) method is used to obtain the final ranking of the projects. The model was verified using the sewer data of Algiers. The results have shown that the method can be used for prioritizing sewer rehabilitation projects.
Effects of in-sewer processes: a stochastic model approach.

PubMed

Vollertsen, J; Nielsen, A H; Yang, W; Hvitved-Jacobsen, T

2005-01-01

Transformations of organic matter, nitrogen and sulfur in sewers can be simulated taking into account the relevant transformation and transport processes. One objective of such simulation is the assessment and management of hydrogen sulfide formation and corrosion. Sulfide is formed in the biofilms and sediments of the water phase, but corrosion occurs on the moist surfaces of the sewer gas phase. Consequently, both phases and the transport of volatile substances between these phases must be included. Furthermore, wastewater composition and transformations in sewers are complex and subject to high, natural variability. This paper presents the latest developments of the WATS model concept, allowing integrated aerobic, anoxic and anaerobic simulation of the water phase and of gas phase processes. The resulting model is complex and with high parameter variability. An example applying stochastic modeling shows how this complexity and variability can be taken into account.
Stable isotopes of water as a natural tracer for infiltration into urban sewer systems

NASA Astrophysics Data System (ADS)

Kracht, O.; Gresch, M.; de Bénédittis, J.; Prigiobbe, V.; Gujer, W.

2003-04-01

An adequate understanding of the hydraulic interaction between leaky sewers and groundwater is essential for the sustainable management of both sewer systems and aquifers in urbanized areas. Undesirable infiltration of groundwater into sewers can contribute over 50% of the total discharge and is detrimental to treatment plant efficiency. On the other hand, in many European cities groundwater surface levels seem to be particularly controlled by the drainage effect of permeable sewer systems. However, nowadays methods for the quantification of these exchange processes are still subject to considerable uncertainties due to their underlying assumptions. The frequently used assumption that the night time minimum in the diurnal wastewater hydrograph is equal to the "parasitic discharge" has to be reconsidered to today's patterns of human life as well as to the long residence time of wastewater in the sewer networks of modern cities. The suitability of stable water isotopes as a natural tracer to differentiate the origin of water in the sewer ("real" wastewater or infiltrating groundwater) is currently investigated in three different catchment areas. The studies are carried out within the framework of the European research project APUSS (Assessing Infiltration and Exfiltration on the Performance of Urban Sewer Systems): 1) The village of Rümlang (Zürich, Switzerland) is predominantly served with drinking water from the Lake Zürich. A large fraction of the lakes water is derived from precipitation in the Alps. This drinking water represents the intrinsic provenience of the wastewater with an δ18O value around -11,5 per mill and δ^2H value around -82 per mill vs. SMOW. In contrast, the local groundwater is originating from precipitation in a moderate altitude of about 450 m above sea level and shows comparatively enriched mean δ18O values of -9,7 per mill and δ^2H values of -70 per mill with only small natural variations. The isotopic separation between these endmembers is basically sufficient to estimate the ratio of infiltrating water in the sewer. Uncertainties yet derive from varying amounts of local groundwater in the water supply mains. These will be substituted by additionally purchased lake water in the next experimental stage. 2) The experimental site Toraccia (suburb of Rome, Italy) obtains drinking water from the Peschiera springs group that is situated in the central Apennines chain about 90 km north east of Rome. This spring water is transported to Rome by an aqueduct. A first campaign revealed an average mains water δ18O value of -8,4 per mill and δ^2H value of -53 per mill. Potential sources of infiltration are occurrences of perched groundwater. These appear to be enriched compared to the drinking water about 2 to 3 per mill in the δ18O and 10 to 20 per mill in the δ^2H value, but show disadvantageous strong variations. 3) Investigations in the urban area of Lyon (France) benefit from the isotopic differences between underground waters originating from the two rivers Rhone and Saone and their associated alluvial aquifers. The oxygen isotope composition of the Rhone water is roughly 3 per mill lighter than that of the river Saone, due to the large differences in the mean altitude and topographic situation of their catchment basins. Considerable amounts of mains water are extracted by production wells in the Rhone aquifer. In consequence a usable difference in the oxygen isotope composition between wastewater and local groundwater of about 1.5 per mill is available for application studies in certain parts of the city.
An analytical probabilistic model of the quality efficiency of a sewer tank

NASA Astrophysics Data System (ADS)

Balistrocchi, Matteo; Grossi, Giovanna; Bacchi, Baldassare

2009-12-01

The assessment of the efficiency of a storm water storage facility devoted to the sewer overflow control in urban areas strictly depends on the ability to model the main features of the rainfall-runoff routing process and the related wet weather pollution delivery. In this paper the possibility of applying the analytical probabilistic approach for developing a tank design method, whose potentials are similar to the continuous simulations, is proved. In the model derivation the quality issues of such devices were implemented. The formulation is based on a Weibull probabilistic model of the main characteristics of the rainfall process and on a power law describing the relationship between the dimensionless storm water cumulative runoff volume and the dimensionless cumulative pollutograph. Following this approach, efficiency indexes were established. The proposed model was verified by comparing its results to those obtained by continuous simulations; satisfactory agreement is shown for the proposed efficiency indexes.
Measurement of infiltration rates in urban sewer systems by use of oxygen isotopes.

PubMed

De Bénédittis, J; Bertrand-Krajewski, J L

2005-01-01

The paper presents the principle of a method to measure infiltration rates in sewer systems based on the use of oxygen isotopes and its application in Lyon (France). In the urban area of Lyon, significant differences in delta 18O that can reach 3 per thousand are observed between the oxygen isotopic compositions of groundwater originating from Rhone, Saone and from their associated alluvial aquifers. Drinking water supplying Lyon results mainly from pumping in the Rhone alluvial aquifer. Therefore, in some areas, the difference of isotopic composition between wastewater resulting from the consumption of drinking water and local groundwater can be used to measure infiltration in sewer systems. The application in the catchment of Ecully shows that the infiltration flow rate presents strong fluctuations at an hourly scale: it varies between 15 and 40 m3/h. This variability could be explained by non-constant discharges of pumping and by variations of the water level in the sewer.
Monitoring in inline storage sewers for stormwater treatment to determine efficiencies.

PubMed

Frehmann, T; Mietzel, T; Kutzner, R; Spengler, B; Geiger, W F

2004-01-01

A special structure of combined sewer overflow tanks is the inline storage sewer with downstream discharge (SKU). This layout has the advantage that besides the sewer system, no other structures are required for storm water treatment. Consequently only very little space is required and compared to combined sewer overflow tanks, there is an enormous potential in reducing costs during construction. To investigate the efficiency of an inline storage sewer, a monitoring station was established in Dortmund-Scharnhorst, Germany. The monitoring station was in operation for a period of 2.5 years. Within this period water samples were taken during a total of 20 discharge events. Besides the complete hydraulic data collection, seven water samplers took more than 5,000 water samples during dry and wet weather. This adds up to a total of more than 20,000 individual lab analyses. The average of the total efficiency for the SKU-West is 86%. 29% of this efficiency can be attributed to the throttle flow. The remaining 57% can be divided into a part of 48% that can be attributed to the process storage and 9% that can be attributed to sedimentation and erosion process.
Association between Gastrointestinal Illness and Precipitation in Areas Impacted by Combined Sewer Facilities: Analysis of Massachusetts Data, 2003-2007

EPA Science Inventory

Background: Combined sewer systems (CSS) collect rainwater runoff, sewage, and industrial wastewater for transit to treatment facilities. With heavy precipitation, volumes can exceed capacity of treatment facilities, and wastewater discharges directly to receiving waters. These c...
Simulation of sulfide buildup in wastewater and atmosphere of sewer networks.

PubMed

Nielsen, A H; Yongsiri, C; Hvitved-Jacobsen, T; Vollertsen, J

2005-01-01

A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.
Hydrogen sulfide emission in sewer networks: a two-phase modeling approach to the sulfur cycle.

PubMed

Yongsiri, C; Vollertsen, J; Hvitved-Jacobsen, T

2004-01-01

Wherever transport of anaerobic wastewater occurs, potential problems associated with hydrogen sulfide in relation to odor nuisance, health risk and corrosion exist. Improved understanding of prediction of hydrogen sulfide emission into the sewer atmosphere is needed for better evaluation of such problems in sewer networks. A two-phase model for emission of hydrogen sulfide along stretches of gravity sewers is presented to estimate the occurrence of both sulfide in the water phase and hydrogen sulfide in the sewer atmosphere. The model takes into account air-water mass transfer of hydrogen sulfide and interactions with other processes in the sulfur cycle. Various emission scenarios are simulated to illustrate the release characteristics of hydrogen sulfide.
Fibre-optic distributed temperature sensing in combined sewer systems.

PubMed

Schilperoort, R P S; Clemens, F H L R

2009-01-01

This paper introduces the application of fibre-optic distributed temperature sensing (DTS) in combined sewer systems. The DTS-technique uses a fibre-optic cable that is inserted into a combined sewer system in combination with a laser instrument that performs measurements and logs the data. The DTS-technique allows monitoring in-sewer temperatures with dense spatial and temporal resolutions. The installation of a fibre-optic cable in a combined sewer system has proven feasible. The use of a single instrument in an easy accessible and safe location that can simultaneously monitor up to several hundreds of monitoring locations makes the DTS set-up easy in use and nearly free of maintenance. Temperature data from a one-week monitoring campaign in an 1,850 m combined sewer system shows the level of detail with which in-sewer processes that affect wastewater temperatures can be studied. Individual discharges from house-connections can be tracked in time and space. With a dedicated cable configuration the confluence of wastewater flows can be observed with a potential to derive the relative contributions of contributary flows to a total flow. Also, the inflow and in-sewer propagation of stormwater can be monitored.
Source, Transport, and Fate of Groundwater Contamination at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina

USGS Publications Warehouse

Vroblesky, Don A.; Petkewich, Matthew D.; Landmeyer, James E.; Lowery, Mark A.

2009-01-01

Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater and the storm sewer. The southern plume originates at a nearby new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. Extensive biodegradation of the contamination takes place in the surficial aquifer; however, the biodegradation is insufficient to reduce trichloroethene to less than milligram-per-liter concentrations prior to discharging into the storm sewers. The groundwater volatile organic compounds entering the storm sewers are substantially diluted by tidal flushing upon entry and are subject to volatilization as they are transported through the storm sewer to a discharge point in a tributary to Ballast Creek. TCE concentrations of about 2-6 micrograms per liter were present in storm-sewer water near the discharge point (sampled at manhole STS26). On three out of four sampling events at manhole STS14, the storm-sewer water contained no vinyl chloride. During a time of relatively high groundwater levels, however, 20 micrograms per liter of vinyl chloride was present in STS14 storm-sewer water. Because groundwater leaks into that storm sewer and because the storm sewer upgradient from manhole STS14 is adjacent to part of the aquifer where 2,290 micrograms per liter of vinyl chloride have been detected, there is a potential for substantially increased concentrations of vinyl chloride to discharge at the storm-sewer outfall under conditions of high groundwater levels and low tidal flushing. In addition, the observation that free-phase tetrachloroethene may have entered the storm-sewer system during the 1994 discharge means that dense nonaqueous phase liquid tetrachloroethene could have leaked from various parts of the storm sewer or discharged to surface water at the storm-sewer outfall.
Green-blue water in the city: quantification of impact of source control versus end-of-pipe solutions on sewer and river floods.

PubMed

De Vleeschauwer, K; Weustenraad, J; Nolf, C; Wolfs, V; De Meulder, B; Shannon, K; Willems, P

2014-01-01

Urbanization and climate change trends put strong pressures on urban water systems. Temporal variations in rainfall, runoff and water availability increase, and need to be compensated for by innovative adaptation strategies. One of these is stormwater retention and infiltration in open and/or green spaces in the city (blue-green water integration). This study evaluated the efficiency of three adaptation strategies for the city of Turnhout in Belgium, namely source control as a result of blue-green water integration, retention basins located downstream of the stormwater sewers, and end-of-pipe solutions based on river flood control reservoirs. The efficiency of these options is quantified by the reduction in sewer and river flood frequencies and volumes, and sewer overflow volumes. This is done by means of long-term simulations (100-year rainfall simulations) using an integrated conceptual sewer-river model calibrated to full hydrodynamic sewer and river models. Results show that combining open, green zones in the city with stormwater retention and infiltration for only 1% of the total city runoff area would lead to a 30 to 50% reduction in sewer flood volumes for return periods in the range 10-100 years. This is due to the additional surface storage and infiltration and consequent reduction in urban runoff. However, the impact of this source control option on downstream river floods is limited. Stormwater retention downstream of the sewer system gives a strong reduction in peak discharges to the receiving river. However due to the difference in response time between the sewer and river systems, this does not lead to a strong reduction in river flood frequency. The paper shows the importance of improving the interface between urban design and water management, and between sewer and river flood management.
Assessing the efficiency of different CSO positions based on network graph characteristics.

PubMed

Sitzenfrei, R; Urich, C; Möderl, M; Rauch, W

2013-01-01

The technical design of urban drainage systems comprises two major aspects: first, the spatial layout of the sewer system and second, the pipe-sizing process. Usually, engineers determine the spatial layout of the sewer network manually, taking into account physical features and future planning scenarios. Before the pipe-sizing process starts, it is important to determine locations of possible weirs and combined sewer overflows (CSOs) based on, e.g. distance to receiving water bodies or to a wastewater treatment plant and available space for storage units. However, positions of CSOs are also determined by topological characteristics of the sewer networks. In order to better understand the impact of placement choices for CSOs and storage units in new systems, this work aims to determine case unspecific, general rules. Therefore, based on numerous, stochastically generated virtual alpine sewer systems of different sizes it is investigated how choices for placement of CSOs and storage units have an impact on the pipe-sizing process (hence, also on investment costs) and on technical performance (CSO efficiency and flooding). To describe the impact of the topological positions of these elements in the sewer networks, graph characteristics are used. With an evaluation of 2,000 different alpine combined sewer systems, it was found that, as expected, with CSOs at more downstream positions in the network, greater construction costs and better performance regarding CSO efficiency result. At a specific point (i.e. topological network position), no significant difference (further increase) in construction costs can be identified. Contrarily, the flooding efficiency increases with more upstream positions of the CSOs. Therefore, CSO and flooding efficiency are in a trade-off conflict and a compromise is required.
Effects of climate and sewer condition on virus transport to groundwater

USDA-ARS?s Scientific Manuscript database

Pathogen contamination from leaky sanitary sewers poses a threat to groundwater quality in urban areas, yet the spatial and temporal dimensions of this contamination are not well understood. In this study, 16 monitoring wells and six municipal wells were repeatedly sampled for human enteric viruses....
18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2012 CFR

2012-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...
18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2014 CFR

2014-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...
18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2013 CFR

2013-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...
18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2011 CFR

2011-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...

Green Infrastructure in the Mix to Reduce District of Columbia Sewer Overflows

EPA Pesticide Factsheets

District of Columbia's Long Term Control Plan to keep sewage out of the city’s rivers is being modified to include a substantial greening component for the first time, making it a dominant feature of 2 of the 3 drainage areas of the combined sewer system.
AN ASSESSMENT OF AUTOMATIC SEWER FLOW SAMPLERS (EPA/600/2-75/065)

EPA Science Inventory

A brief review of the characteristics of storm and combined sewer flows is given followed by a general discussion of the purposes for and requirements of a sampling program. The desirable characteristics of automatic sampling equipment are set forth and problem areas are outlined...
40 CFR 35.2024 - Combined sewer overflows.

Code of Federal Regulations, 2014 CFR

2014-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2024 Combined sewer... project priority list, it addresses impaired uses in priority water quality areas which are due to the... must demonstrate to the Administrator that the water quality goals of the Act will not be achieved...
40 CFR 35.2024 - Combined sewer overflows.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2024 Combined sewer... project priority list, it addresses impaired uses in priority water quality areas which are due to the... must demonstrate to the Administrator that the water quality goals of the Act will not be achieved...
40 CFR 35.2024 - Combined sewer overflows.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2024 Combined sewer... project priority list, it addresses impaired uses in priority water quality areas which are due to the... must demonstrate to the Administrator that the water quality goals of the Act will not be achieved...
Effects of combined sewer overflow and stormwater on indicator bacteria concentrations in the Tama River due to the high population density of Tokyo Metropolitan area.

PubMed

Ham, Young-Sik; Kobori, Hiromi; Takasago, Masahisa

2009-05-01

The indicator bacteria (standard plate count, total coliform, and fecal coliform bacteria) concentrations have been investigated using six ambient habitats (population density, percent sewer penetration, stream flow rate (m(3)/sec), percent residential area, percent forest area and percent agricultural area) in the Tama River basin in Tokyo, Japan during June 2003 to January 2005. The downstream and tributary Tama River showed higher concentrations of TC and FC bacteria than the upstream waters, which exceeded an environmental quality standard for rivers and a bathing water quality criterion. It was estimated that combined sewer overflow (CSO) and stormwater effluents contributed -4-23% to the indicator bacteria concentrations of the Tama River. The results of multiple regression analyses show that the indicator bacteria concentrations of Tama River basin are significantly affected by population density. It is concluded that the Tama River received a significant bacterial contamination load originating from the anthropogenic source.
Multivariate probability distribution for sewer system vulnerability assessment under data-limited conditions.

PubMed

Del Giudice, G; Padulano, R; Siciliano, D

2016-01-01

The lack of geometrical and hydraulic information about sewer networks often excludes the adoption of in-deep modeling tools to obtain prioritization strategies for funds management. The present paper describes a novel statistical procedure for defining the prioritization scheme for preventive maintenance strategies based on a small sample of failure data collected by the Sewer Office of the Municipality of Naples (IT). Novelty issues involve, among others, considering sewer parameters as continuous statistical variables and accounting for their interdependences. After a statistical analysis of maintenance interventions, the most important available factors affecting the process are selected and their mutual correlations identified. Then, after a Box-Cox transformation of the original variables, a methodology is provided for the evaluation of a vulnerability map of the sewer network by adopting a joint multivariate normal distribution with different parameter sets. The goodness-of-fit is eventually tested for each distribution by means of a multivariate plotting position. The developed methodology is expected to assist municipal engineers in identifying critical sewers, prioritizing sewer inspections in order to fulfill rehabilitation requirements.
Combined sewer overflows to surface waters detected by the anthropogenic marker caffeine.

PubMed

Buerge, Ignaz J; Poiger, Thomas; Müller, Markus D; Buser, Hans-Rudolf

2006-07-01

Continuous progress in wastewater treatment technology and the growing number of households connected to wastewater treatment plants (WWTPs) have generally resulted in decreased environmental loading of many pollutants. Nonetheless, further reduction of pollutant inputs is required to improve the quality of surface waters in densely populated areas. In this context, the relative contribution of combined sewer overflows as sources of wastewater-derived contaminants has attracted more and more attention, but the quantitative importance of these overflows has barely been investigated. In this study, caffeine was successfully used as a chemical marker to estimate the fraction of sewer overflows in the catchment area of lake Greifensee, Switzerland. Caffeine is a ubiquitous compound in raw, domestic wastewater with typical per capita loads of approximately 16 mg person(-1) d(-1). In WWTPs of the Greifensee region, caffeine is largely eliminated (>99%), resulting in much smaller loads of < or = 0.15 mg person(-1) d(-1) in treated wastewater. However, in receiving streams as in the inflows to Greifensee, caffeine loads (0.1-1.6 mg person(-1) d(-1)) were higher than those in WWTP effluents, indicating additional sources. As the loads in the streams correlated with precipitation during sampling, it was concluded that combined sewer overflows were the most likely source of caffeine. Using a mass balance approach, it was possible to determine the fraction of wastewater (in dry weather equivalents) discharged untreated to the receiving streams (up to 10%, annual mean, approximately 2-3%). The concept of caffeine as a marker for combined sewer overflows was then applied to estimate phosphorus inputs to Greifensee with untreated and treated wastewater (approximately 1.5 and 2.0 t P y(-1), respectively), which corresponded well with P inputs determined in a separate study based on hydraulic considerations. For compounds with high elimination in WWTPs such as phosphorus (96-98% in the Greifensee area), inputs from combined sewer overflows are thus of similar magnitude as inputs from treated wastewater. The study demonstrated that caffeine is a suitable marker for untreated wastewater (from combined sewer overflows, direct discharges, etc.), but its sensitivity depends on regional conditions and decreases with decreasing elimination efficiency in WWTPs.
Analysis of heavy metal sources in storm water from urban areas

NASA Astrophysics Data System (ADS)

Scherer, U.; Fuchs, S.

2009-04-01

The input of heavy metals into surface waters is a serious impairment of the aquatic environment. The emissions of heavy metals via point and diffuse pathways into the German river basins were thus quantified for the period of 1985 through 2005. The total emission into the German river systems decreased for each metal during the observed period. This reduction is mainly caused by the decline of emissions via point sources. The measures taken by industry and implemented within the scope of a stringently water legislation have decisively contributed to an improvement of environmental conditions. Today's emissions of heavy metals into river basins of Germany are dominated by the input via diffuse pathways. One of the most important diffuse input is the storm water discharged from paved urban areas into the surface waters via storm sewers and combined sewer overflows especially for the metals copper, zinc and lead. The objective of this project was to identify the sources of these three heavy metals washed of from paved urban areas. The use of copper, zinc and lead on the outsides of buildings results in emissions to water and soil via rainwater due to weathering and runoff of soluble and insoluble metallic compounds. Copper and zinc are traditionally used materials in the building sector especially for roofs, gutters and facades. Lead, in contrast, plays only a subordinate role due to its more limited outdoor use. The corrosion rates vary widely. Climatic factors (temperature, humidity etc.), above all the presence of corrosive gases (sulphur dioxide, nitrogen oxide, ozone etc.) influence the corrosion processes. Estimates of industrial associations were referred to in order to determine the corrosion relevant metal surfaces. Heavy metal emissions caused by traffic are complex and depend on many parameters which vary by locality, time and substance. In principle, substances can be emitted by vehicles, the road surface and by maintenance. Emissions of copper, lead and zinc are mainly caused by wear and tear of tyres and brake pads. The reference figures of the environmental emissions are usually the kilometres driven per vehicle. The emissions can then be calculated based on the road performance. Furthermore atmospheric deposition on paved urban areas was considered. The heavy metal emission from each individual source and the portion discharged into surface waters via storm sewers and combined sewer overflows was quantified. The emission sum of all sources was validated using emission data of storm sewers based on measured heavy metal concentrations and the discharge volume showing a good agreement.
A generic methodology for the optimisation of sewer systems using stochastic programming and self-optimizing control.

PubMed

Mauricio-Iglesias, Miguel; Montero-Castro, Ignacio; Mollerup, Ane L; Sin, Gürkan

2015-05-15

The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flow and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems. Such controller is aimed at keeping the system close to the optimal performance, thanks to an optimal selection of controlled variables. The definition of an optimal performance was carried out by a two-stage optimisation (stochastic and deterministic) to take into account both the overflow during the current rain event as well as the expected overflow given the probability of a future rain event. The methodology is successfully applied to design an optimising control strategy for a subcatchment area in Copenhagen. The results are promising and expected to contribute to the advance of the operation and control problem of sewer systems. Copyright © 2015 Elsevier Ltd. All rights reserved.
Flow measurements in sewers based on image analysis: automatic flow velocity algorithm.

PubMed

Jeanbourquin, D; Sage, D; Nguyen, L; Schaeli, B; Kayal, S; Barry, D A; Rossi, L

2011-01-01

Discharges of combined sewer overflows (CSOs) and stormwater are recognized as an important source of environmental contamination. However, the harsh sewer environment and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. An in situ system for sewer water flow monitoring based on video images was evaluated. Algorithms to determine water velocities were developed based on image-processing techniques. The image-based water velocity algorithm identifies surface features and measures their positions with respect to real world coordinates. A web-based user interface and a three-tier system architecture enable remote configuration of the cameras and the image-processing algorithms in order to calculate automatically flow velocity on-line. Results of investigations conducted in a CSO are presented. The system was found to measure reliably water velocities, thereby providing the means to understand particular hydraulic behaviors.
A step towards considering the spatial heterogeneity of urban key features in urban hydrology flood modelling

NASA Astrophysics Data System (ADS)

Leandro, J.; Schumann, A.; Pfister, A.

2016-04-01

Some of the major challenges in modelling rainfall-runoff in urbanised areas are the complex interaction between the sewer system and the overland surface, and the spatial heterogeneity of the urban key features. The former requires the sewer network and the system of surface flow paths to be solved simultaneously. The latter is still an unresolved issue because the heterogeneity of runoff formation requires high detailed information and includes a large variety of feature specific rainfall-runoff dynamics. This paper discloses a methodology for considering the variability of building types and the spatial heterogeneity of land surfaces. The former is achieved by developing a specific conceptual rainfall-runoff model and the latter by defining a fully distributed approach for infiltration processes in urban areas with limited storage capacity dependent on OpenStreetMaps (OSM). The model complexity is increased stepwise by adding components to an existing 2D overland flow model. The different steps are defined as modelling levels. The methodology is applied in a German case study. Results highlight that: (a) spatial heterogeneity of urban features has a medium to high impact on the estimated overland flood-depths, (b) the addition of multiple urban features have a higher cumulative effect due to the dynamic effects simulated by the model, (c) connecting the runoff from buildings to the sewer contributes to the non-linear effects observed on the overland flood-depths, and (d) OSM data is useful in identifying pounding areas (for which infiltration plays a decisive role) and permeable natural surface flow paths (which delay the flood propagation).
Comparison of different synthetic 5-min rainfall time series on the results of rainfall runoff simulations in urban drainage modelling

NASA Astrophysics Data System (ADS)

Krämer, Stefan; Rohde, Sophia; Schröder, Kai; Belli, Aslan; Maßmann, Stefanie; Schönfeld, Martin; Henkel, Erik; Fuchs, Lothar

2015-04-01

The design of urban drainage systems with numerical simulation models requires long, continuous rainfall time series with high temporal resolution. However, suitable observed time series are rare. As a result, usual design concepts often use uncertain or unsuitable rainfall data, which renders them uneconomic or unsustainable. An expedient alternative to observed data is the use of long, synthetic rainfall time series as input for the simulation models. Within the project SYNOPSE, several different methods to generate synthetic rainfall data as input for urban drainage modelling are advanced, tested, and compared. Synthetic rainfall time series of three different precipitation model approaches, - one parametric stochastic model (alternating renewal approach), one non-parametric stochastic model (resampling approach), one downscaling approach from a regional climate model-, are provided for three catchments with different sewer system characteristics in different climate regions in Germany: - Hamburg (northern Germany): maritime climate, mean annual rainfall: 770 mm; combined sewer system length: 1.729 km (City center of Hamburg), storm water sewer system length (Hamburg Harburg): 168 km - Brunswick (Lower Saxony, northern Germany): transitional climate from maritime to continental, mean annual rainfall: 618 mm; sewer system length: 278 km, connected impervious area: 379 ha, height difference: 27 m - Friburg in Brisgau (southern Germany): Central European transitional climate, mean annual rainfall: 908 mm; sewer system length: 794 km, connected impervious area: 1 546 ha, height difference 284 m Hydrodynamic models are set up for each catchment to simulate rainfall runoff processes in the sewer systems. Long term event time series are extracted from the - three different synthetic rainfall time series (comprising up to 600 years continuous rainfall) provided for each catchment and - observed gauge rainfall (reference rainfall) according national hydraulic design standards. The synthetic and reference long term event time series are used as rainfall input for the hydrodynamic sewer models. For comparison of the synthetic rainfall time series against the reference rainfall and against each other the number of - surcharged manholes, - surcharges per manhole, - and the average surcharge volume per manhole are applied as hydraulic performance criteria. The results are discussed and assessed to answer the following questions: - Are the synthetic rainfall approaches suitable to generate high resolution rainfall series and do they produce, - in combination with numerical rainfall runoff models - valid results for design of urban drainage systems? - What are the bounds of uncertainty in the runoff results depending on the synthetic rainfall model and on the climate region? The work is carried out within the SYNOPSE project, funded by the German Federal Ministry of Education and Research (BMBF).
Reducing pathogens in combined sewer overflows using ozonation or UV irradiation.

PubMed

Tondera, Katharina; Klaer, Kassandra; Gebhardt, Jens; Wingender, Jost; Koch, Christoph; Horstkott, Marina; Strathmann, Martin; Jurzik, Lars; Hamza, Ibrahim Ahmed; Pinnekamp, Johannes

2015-11-01

Fecal contamination of water resources is a major public health concern in densely populated areas since these water bodies are used for drinking water production or recreational purposes. A main source of this contamination originates from combined sewer overflows (CSOs) in regions with combined sewer systems. Thus, the treatment of CSO discharges is urgent. In this study, we explored whether ozonation or UV irradiation can efficiently reduce pathogenic bacteria, viruses, and protozoan parasites in CSOs. Experiments were carried out in parallel settings at the outflow of a stormwater settling tank in the Ruhr area, Germany. The results showed that both techniques reduce most hygienically relevant bacteria, parasites and viruses. Under the conditions tested, ozonation yielded lower outflow values for the majority of the tested parameters. Copyright © 2015 Elsevier GmbH. All rights reserved.
78 FR 41803 - Notice of Lodging of Proposed Amendment to Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-11

... original 2012 consent decree, the Metropolitan St. Louis Sewer District (``MSD'') agreed to undertake... specific combined sewer overflow control measures. MSD still is in the process of complying with the 2012...
Functional evaluation of pollutant transformation in sediment from combined sewer system.

PubMed

Shi, Xuan; Ngo, Huu Hao; Sang, Langtao; Jin, Pengkang; Wang, Xiaochang C; Wang, Guanghua

2018-07-01

In this study, a pilot combined sewer system was constructed to characterize the pollutant transformation in sewer sediment. The results showed that particulate contaminants deposited from sewage could be transformed into dissolved matter by distinct pollutant transformation pathways. Although the oxidation-reduction potential (ORP) was varied from -80 mV to -340 mV in different region of the sediment, the fermentation was the dominant process in all regions of the sediment, which induced hydrolysis and decomposition of particulate contaminants. As a result, the accumulation of dissolved organic matter and the variation of ORP values along the sediment depth led to the depth-dependent reproduction characteristics of methanogens and sulfate-reducing bacteria, which were existed in the middle and deep layer of the sediment respectively. However, the diversity of nitrifying and polyphosphate-accumulating bacteria was low in sewer sediment and those microbial communities showed a non-significant correlation with nitrogen and phosphorus contaminants, which indicated that the enrichment of nitrogen and phosphorus contaminants was mainly caused by physical deposition process. Thus, this study proposed a promising pathway to evaluate pollutant transformation and can help provide theoretical foundation for urban sewer improvement. Copyright © 2018 Elsevier Ltd. All rights reserved.
Tidal river sediments in the Washington, D.C. area. 11. Distribution and sources of organic containmants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wade, T.L.; Velinsky, D.J.; Reinharz, E.

1994-06-01

Concentrations of aliphatic, aromatic, and chlorinated hydrocarbons were determined from 33 surface-sediment samples taken from the Tidal Basin, Washington Ship Channel, and the Anacostia and Potomac rivers in Washington, D.C. In conjunction with these samples, selected storm sewers and outfalls also were sampled to help elucidate general sources of contamination to the area. All of the sediments contained detectable concentrations of aliphatic and aromatic hydrocarbons, DDT (total dichlorodiphenytrichloroethande), DDE (dichlorodiphenyldichloroethene), DDD (dichlorodiphenyldichloroethane), PCBx (total polychlorinated biphenyls) and total chlordanes (oxy-, {alpha}-, and {gamma}-chlordane and cis + trans-nonachlor). Sediment concentrations of most contaminants were highest in the Anacostia River just downstreammore » of the Washington Navy Yard, except for total chlordane, which appeared to have upstream sources in addition to storm and combined sewer runoff. This area has the highest number of storm and combined sewer outfalls in the river. Potomac River stations had lower concentrations than other stations. Polycyclic aromatic hydrocarbons, saturated hydrocarbons, and the unresolved complex mixture (UCM) distributions reflect mixtures of combustion products and direct discharges of petroleum products. Sources of PCBs appear to be related to specific outfalls, while hydrocarbon inputs, especially PAHs, are diffuse, and may be related to street runoff. This study indicates that in large urban areas, nonpoint sources deliver substantial amounts of contaminants to ecosystems through storm and combined sewer systems, and control of these inputs must be addressed. 33 refs., 6 figs., 3 tabs.« less
The Ecology of Acidophilic Microorganisms in the Corroding Concrete Sewer Environment

PubMed Central

Li, Xuan; Kappler, Ulrike; Jiang, Guangming; Bond, Philip L.

2017-01-01

Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11–10 (pristine concrete) to pH 2–4. Acidophilic microorganisms become established as biofilms within the concrete corrosion layer and enhance the loss of concrete mass. Until recently, the acidophilic community was considered to comprise relatively few species of microorganisms, however, the biodiversity of the corrosion community is now recognized as being extensive and varying from different sewer environmental conditions. The diversity of acidophiles in the corrosion communities includes chemolithoautotrophs, chemolithoheterotrophs, and chemoorganoheterotrophs. The activity of these microorganisms is strongly affected by H2S levels in the sewer gas phase, although CO2, organic matter, and iron in the corrosion layer influence this acidic ecosystem. This paper briefly presents the conditions within the sewer that lead to the development of concrete corrosion in that environment. The review focuses on the acidophilic microorganisms detected in sewer corrosion environments, and then summarizes their proposed functions and physiology, especially in relation to the corrosion process. To our knowledge, this is the first review of acidophilic corrosion microbial communities, in which, the ecology and the environmental conditions (when available) are considered. Ecological studies of sewer corrosion are limited, however, where possible, we summarize the important metabolic functions of the different acidophilic species detected in sewer concrete corrosion layers. It is evident that microbial functions in the acidic sewer corrosion environment can be linked to those occurring in the analogous acidic environments of acid mine drainage and bioleaching. PMID:28473816
The Ecology of Acidophilic Microorganisms in the Corroding Concrete Sewer Environment.

PubMed

Li, Xuan; Kappler, Ulrike; Jiang, Guangming; Bond, Philip L

2017-01-01

Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11-10 (pristine concrete) to pH 2-4. Acidophilic microorganisms become established as biofilms within the concrete corrosion layer and enhance the loss of concrete mass. Until recently, the acidophilic community was considered to comprise relatively few species of microorganisms, however, the biodiversity of the corrosion community is now recognized as being extensive and varying from different sewer environmental conditions. The diversity of acidophiles in the corrosion communities includes chemolithoautotrophs, chemolithoheterotrophs, and chemoorganoheterotrophs. The activity of these microorganisms is strongly affected by H 2 S levels in the sewer gas phase, although CO 2 , organic matter, and iron in the corrosion layer influence this acidic ecosystem. This paper briefly presents the conditions within the sewer that lead to the development of concrete corrosion in that environment. The review focuses on the acidophilic microorganisms detected in sewer corrosion environments, and then summarizes their proposed functions and physiology, especially in relation to the corrosion process. To our knowledge, this is the first review of acidophilic corrosion microbial communities, in which, the ecology and the environmental conditions (when available) are considered. Ecological studies of sewer corrosion are limited, however, where possible, we summarize the important metabolic functions of the different acidophilic species detected in sewer concrete corrosion layers. It is evident that microbial functions in the acidic sewer corrosion environment can be linked to those occurring in the analogous acidic environments of acid mine drainage and bioleaching.
Magnitude and frequency of flooding on small urban watersheds in the Tampa Bay area, west-central Florida

USGS Publications Warehouse

Lopez, M.A.; Woodham, W.M.

1983-01-01

Hydrologic data collected on nine small urban watersheds in the Tampa Bay area of west-central Florida and a method for estimating peak discharges in the study area are described. The watersheds have mixed land use and range in size from 0.34 to 3.45 square miles. Watershed soils, land use, and storm-drainage system data are described. Urban development ranged from a sparsely populated area with open-ditch storm sewers and 19% impervious area to a completely sewered watershed with 61% impervious cover. The U.S. Geological Survey natural-basin and urban-watershed models were calibrated for the nine watersheds using 5-minute interval rainfall data from the Tampa, Florida, National Weather Service rain gage to simulate annual peak discharge for the period 1906-52. A log-Pearson Type III frequency analysis of the simulated annual maximum discharge was used to determine the 2-, 5-, 10-, 25-, 50-, and 100-year flood discharges for each watershed. Flood discharges were related in a multiple-linear regression to drainage area, channel slope, detention storage area, and an urban-development factor determined by the extent of curb and gutter street drainage and storm-sewer system. The average standard error for the regional relations ranged from + or - 32 to + or - 42%. (USGS)

Groundwater infiltration, surface water inflow and sewerage exfiltration considering hydrodynamic conditions in sewer systems.

PubMed

Karpf, Christian; Hoeft, Stefan; Scheffer, Claudia; Fuchs, Lothar; Krebs, Peter

2011-01-01

Sewer systems are closely interlinked with groundwater and surface water. Due to leaks and regular openings in the sewer system (e.g. combined sewer overflow structures with sometimes reverse pressure conditions), groundwater infiltration and surface water inflow as well as exfiltration of sewage take place and cannot be avoided. In the paper a new hydrodynamic sewer network modelling approach will be presented, which includes--besides precipitation--hydrographs of groundwater and surface water as essential boundary conditions. The concept of the modelling approach and the models to describe the infiltration, inflow and exfiltration fluxes are described. The model application to the sewerage system of the City of Dresden during a flood event with complex conditions shows that the processes of infiltration, exfiltration and surface water inflows can be described with a higher reliability and accuracy, showing that surface water inflow causes a pronounced system reaction. Further, according to the simulation results, a high sensitivity of exfiltration rates on the in-sewer water levels and a relatively low influence of the dynamic conditions on the infiltration rates were found.
Assessment on inflow and infiltration in sewerage systems of Kuantan, Pahang.

PubMed

Yap, Hiew Thong; Ngien, Su Kong

2017-12-01

Inflow and infiltration are important aspects of sewerage systems that need to be considered during the design stage and constantly monitored once the sewerage system is in operation. The aim of this research is to analyse the relationship of rainfall as well as inflow infiltration with sewage flow patterns through data collected from fieldwork. Three sewer pipelines were selected at the residential areas of Taman Lepar Hilir Saujana, Bandar Putra and Kota Sas for data collection. Sewage flow data were collected in terms of flowrate, velocity and depth of flow using flowmeters with ultrasonic sensors that utilize the continuous Doppler effect in the sewer pipelines, while rainfall intensity data were collected using rain gauges installed at the study locations. Based on the result, the average infiltration rates of Q peak and Q ave for the locations were 17% and 21%, which exceeded the respective values of 5% and 10% stated in Hammer and Hammer. The flowrate of wastewater in the sewer pipelines was found to be directly proportional to rainfall. These findings indicate that the sewer pipelines in the study areas may have been affected by capacity reduction, whereas the sewerage treatment plants receiving the wastewater influent may have been overloaded.
Storm water management in an urban catchment: effects of source control and real-time management of sewer systems on receiving water quality.

PubMed

Frehmann, T; Nafo, I; Niemann, A; Geiger, W F

2002-01-01

For the examination of the effects of different storm water management strategies in an urban catchment area on receiving water quality, an integrated simulation of the sewer system, wastewater treatment plant and receiving water is carried out. In the sewer system real-time control measures are implemented. As examples of source control measures the reduction of wastewater and the reduction of the amount of impervious surfaces producing storm water discharges are examined. The surface runoff calculation and the simulation of the sewer system and the WWTP are based on a MATLAB/SIMULINK simulation environment. The impact of the measures on the receiving water is simulated using AQUASIM. It can be shown that the examined storm water management measures, especially the source control measures, can reduce the combined sewer overflow volume and the pollutant discharge load considerably. All examined measures also have positive effects on the receiving water quality. Moreover, the reduction of impervious surfaces avoids combined sewer overflow activities, and in consequence prevents pollutants from discharging into the receiving water after small rainfall events. However, the receiving water quality improvement may not be seen as important enough to avoid acute receiving water effects in general.
Identification of controlling factors for the initiation of corrosion of fresh concrete sewers.

PubMed

Jiang, Guangming; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

2015-09-01

The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The corrosion initiation time was also shortened by higher gas temperature due to its positive impact on reaction kinetics. These findings provide real opportunities for pro-active sewer asset management with the aim to delay the on-set of the corrosion processes, and hence extend the service life of sewers, through improved prediction and optimization capacity. Copyright © 2015 Elsevier Ltd. All rights reserved.
Monitoring the performance of a storm water separating manifold with distributed temperature sensing.

PubMed

Langeveld, J G; de Haan, C; Klootwijk, M; Schilperoort, R P S

2012-01-01

Storm water separating manifolds in house connections have been introduced as a cost effective solution to disconnect impervious areas from combined sewers. Such manifolds have been applied by the municipality of Breda, the Netherlands. In order to investigate the performance of the manifolds, a monitoring technique (distributed temperature sensing or DTS) using fiber optic cables has been applied in the sewer system of Breda. This paper describes the application of DTS as a research tool in sewer systems. DTS proves to be a powerful tool to monitor the performance of (parts of) a sewer system in time and space. The research project showed that DTS is capable of monitoring the performance of house connections and identifying locations of inflow of both sewage and storm runoff. The research results show that the performance of storm water separating manifolds varies over time, thus making them unreliable.
A mathematical model to predict the effect of heat recovery on the wastewater temperature in sewers.

PubMed

Dürrenmatt, David J; Wanner, Oskar

2014-01-01

Raw wastewater contains considerable amounts of energy that can be recovered by means of a heat pump and a heat exchanger installed in the sewer. The technique is well established, and there are approximately 50 facilities in Switzerland, many of which have been successfully using this technique for years. The planning of new facilities requires predictions of the effect of heat recovery on the wastewater temperature in the sewer because altered wastewater temperatures may cause problems for the biological processes used in wastewater treatment plants and receiving waters. A mathematical model is presented that calculates the discharge in a sewer conduit and the spatial profiles and dynamics of the temperature in the wastewater, sewer headspace, pipe, and surrounding soil. The model was implemented in the simulation program TEMPEST and was used to evaluate measured time series of discharge and temperatures. It was found that the model adequately reproduces the measured data and that the temperature and thermal conductivity of the soil and the distance between the sewer pipe and undisturbed soil are the most sensitive model parameters. The temporary storage of heat in the pipe wall and the exchange of heat between wastewater and the pipe wall are the most important processes for heat transfer. The model can be used as a tool to determine the optimal site for heat recovery and the maximal amount of extractable heat. Copyright © 2013 Elsevier Ltd. All rights reserved.
Modeling of the fate of radionuclides in urban sewer systems after contamination due to nuclear or radiological incidents.

PubMed

Urso, L; Kaiser, J C; Andersson, K G; Andorfer, H; Angermair, G; Gusel, C; Tandler, R

2013-04-01

After an accidental radioactive contamination by aerosols in inhabited areas, the radiation exposure to man is determined by complex interactions between different factors such as dry or wet deposition, different types of ground surfaces, chemical properties of the radionuclides involved and building development as well as dependence on bomb construction e.g. design and geometry. At short-term, the first rainfall is an important way of natural decontamination: deposited radionuclides are washed off from surfaces and in urban areas the resulting contaminated runoff enters the sewer system and is collected in a sewage plant. Up to now the potential exposure caused by this process has received little attention and is estimated here with simulation models. The commercial rainfall-runoff model for urban sewer systems KANAL++ has been extended to include transport of radionuclides from surfaces through the drainage to various discharge facilities. The flow from surfaces is modeled by unit hydrographs, which produce boundary conditions for a system of 1d coupled flow and transport equations in a tube system. Initial conditions are provided by a map of surface contamination which is produced by geo-statistical interpolation of γ-dose rate measurements taking into account the detector environment. The corresponding methodology is implemented in the Inhabited Area Monitoring Module (IAMM) software module as part of the European decision system JRODOS. A hypothetical scenario is considered where a Radiation Dispersal Device (RDD) with Cs-137 is detonated in a small inhabited area whose drainage system is realistically modeled. The transition of deposited radionuclides due to rainfall into the surface runoff is accounted for by different nuclide-specific entrainment coefficients for paved and unpaved surfaces. The concentration of Cs-137 in water is calculated at the nodes of the drainage system and at the sewage treatment plant. The external exposure to staff of the treatment plant is estimated. For Cs-137 radiation levels in the plant are low since wash-off of cesium from surfaces is an ineffective process. Copyright © 2012 Elsevier Ltd. All rights reserved.
Development of Sediment Deposition Height Capacity Equation in Sewer Networks

NASA Astrophysics Data System (ADS)

Song, Yangho; Jo, Deokjun; Lee, Jungho

2017-04-01

Sediment characteristics and transport processes in sewers are markedly different from river. There is a wide range of particle densities and smaller particle size variation in sewers. Sediment supply and the available erodible material are more limited in sewers, and the diverse hydraulic characteristics in sewer systems are more unsteady. Prevention of sewer sediment accumulation, which can cause major sewer operational problems, is imperative and has been an immense concern for engineers. The effects of sediment formation in sewer systems, an appropriate sediment transport modelling with the ability to determine the location and depth of sediment deposit is needed. It is necessary to design efficiently considering the transfer and settling phenomena of the sediment coming into the sewer systems. During transport in the sewer, the minimum shear flow velocity and possible shear stress at which the sediment is transported smoothly. However, the interaction of sediment and fluid within the sewer systems has been very complex and the rigorous theoretical handling of this problem has not been developed. It is derived from the empirical values obtained from the river bed. The basic theory that particles float is based on the balance between sedimentation of particles by gravity and turbulent diffusion of fluids. There are many variables related. Representative parameters include complex phenomena due to collisions between particles, particles and fluids, and interactions between particles and tube walls. In general, the main parameters that form the boundary between the main transport and sediment are particle size, density, volume fraction, pipe diameter and gravity. As the particle size and volume concentration increase, the minimum feed rate increases and the same tendency is observed for the change of the capillary diameter. Based on this tendency, this study has developed a sediment deposition height capacity formula to take into consideration the sewer discharge capacity. The main objective in undertaking this research is the assessment of the sediment scouring and transporting capacity of the discharged. Acknowledgements This research was supported by a grant(13AWMP-B066744-01) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.
Factors that influence properties of FOG deposits and their formation in sewer collection systems.

PubMed

Iasmin, Mahbuba; Dean, Lisa O; Lappi, Simon E; Ducoste, Joel J

2014-02-01

Understanding the formation of Fat, Oil, and Grease (FOG) deposits in sewer systems is critical to the sustainability of sewer collection systems since they have been implicated in causing sewerage blockages that leads to sanitary sewer overflows (SSOs). Recently, FOG deposits in sewer systems displayed strong similarities with calcium-based fatty acid salts as a result of a saponification reaction. The objective of this study was to quantify the factors that may affect the formation of FOG deposits and their chemical and rheological properties. These factors included the types of fats used in FSEs, environmental conditions (i.e. pH and temperature), and the source of calcium in sewer systems. The results of this study showed that calcium content in the calcium based salts seemed to depend on the solubility limit of the calcium source and influenced by pH and temperature conditions. The fatty acid profile of the calcium-based fatty acid salts produced under alkali driven hydrolysis were identical to the profile of the fat source and did not match the profile of field FOG deposits, which displayed a high fraction of palmitic, a long chain saturated fatty acid. It is hypothesized that selective microbial metabolism of fats and/or biologically induced hydrogenation may contribute to the FOG deposit makeup in sewer system. Therefore, selective removal of palmitic in pretreatment processes may be necessary prior to the discharge of FSE wastes into the sewer collection system. Copyright © 2013 Elsevier Ltd. All rights reserved.
Anoxic control of odour and corrosion from sewer networks.

PubMed

Yang, W; Vollertsen, J; Hvitved-Jacobsen, T

2004-01-01

Anoxic processes can effectively control odour and corrosion in sewer networks. However, the absence of fundamental knowledge on the kinetics of anoxic transformation of sewage prevents the engineering applications of anoxic control in sewers. This paper focuss on a basic understanding of the anoxic transformations needed for a conceptual simulation of the water phase processes. Experiments conducted in batch reactors have shown that nitrite builds up in wastewater during denitrification. Part of the nitrate-reducing biomass is capable of utilizing nitrite after nitrate is depleted. Compared with aerobic transformation, anoxic processes have low values of maximum growth rate of the biomass and also a low endogenous respiration rate. Heterotrophic yield determined under anoxic conditions, at level of 0.25 mmol e-eq (mmol e-eq)(-1), accounted for less than 40% of the corresponding aerobic values.
The erosion behaviour of biologically active sewer sediment deposits: observations from a laboratory study.

PubMed

Banasiak, Robert; Verhoeven, Ronny; De Sutter, Renaat; Tait, Simon

2005-12-01

The erosion behaviour of various fine-grained sediment deposits has been investigated in laboratory experiments. This work mainly focused on tests using sewer sediment in which strong biochemical reactions were observed during the deposit formation period. A small number of initial tests were conducted in which the deposits were made from mixtures of "clean" mineral and organic sediments. The erosion behaviour observed in these tests was compared with the erosion characteristics for sediments taken from deposits in a sewer. The impact of the biological processes on physical properties such as bulk density, water content, deposit structure and the erosive behaviour as a function of bed shear stress are quantified and discussed. Based on these observations it is believed that bio-processes weaken the strength of the in-pipe sediment deposits. A significantly weaker sediment surface layer was observed during deposition under quiescent oxygen-rich conditions. This resulted in a deposit with low shear strength which may be a cause of a first foul flush of suspended sediment when flow rates were increased. Comparison between tests with sewer sediments and the artificial representative surrogates suggested that the deposits of the later did not correctly simulate the depositional development and the resultant erosion patterns observed with the more bio-active sewer sediment.
Sewer deterioration modeling with condition data lacking historical records.

PubMed

Egger, C; Scheidegger, A; Reichert, P; Maurer, M

2013-11-01

Accurate predictions of future conditions of sewer systems are needed for efficient rehabilitation planning. For this purpose, a range of sewer deterioration models has been proposed which can be improved by calibration with observed sewer condition data. However, if datasets lack historical records, calibration requires a combination of deterioration and sewer rehabilitation models, as the current state of the sewer network reflects the combined effect of both processes. Otherwise, physical sewer lifespans are overestimated as pipes in poor condition that were rehabilitated are no longer represented in the dataset. We therefore propose the combination of a sewer deterioration model with a simple rehabilitation model which can be calibrated with datasets lacking historical information. We use Bayesian inference for parameter estimation due to the limited information content of the data and limited identifiability of the model parameters. A sensitivity analysis gives an insight into the model's robustness against the uncertainty of the prior. The analysis reveals that the model results are principally sensitive to the means of the priors of specific model parameters, which should therefore be elicited with care. The importance sampling technique applied for the sensitivity analysis permitted efficient implementation for regional sensitivity analysis with reasonable computational outlay. Application of the combined model with both simulated and real data shows that it effectively compensates for the bias induced by a lack of historical data. Thus, the novel approach makes it possible to calibrate sewer pipe deterioration models even when historical condition records are lacking. Since at least some prior knowledge of the model parameters is available, the strength of Bayesian inference is particularly evident in the case of small datasets. Copyright © 2013 Elsevier Ltd. All rights reserved.
Evaluating rain gardens as a method to reduce the impact of sewer overflows in sources of drinking water.

PubMed

Autixier, Laurène; Mailhot, Alain; Bolduc, Samuel; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Prévost, Michèle; Dorner, Sarah

2014-11-15

The implications of climate change and changing precipitation patterns need to be investigated to evaluate mitigation measures for source water protection. Potential solutions need first to be evaluated under present climate conditions to determine their utility as climate change adaptation strategies. An urban drainage network receiving both stormwater and wastewater was studied to evaluate potential solutions to reduce the impact of combined sewer overflows (CSOs) in a drinking water source. A detailed hydraulic model was applied to the drainage basin to model the implementation of best management practices at a drainage basin scale. The model was calibrated and validated with field data of CSO flows for seven events from a survey conducted in 2009 and 2010. Rain gardens were evaluated for their reduction of volumes of water entering the drainage network and of CSOs. Scenarios with different levels of implementation were considered and evaluated. Of the total impervious area within the basin directly connected to the sewer system, a maximum of 21% could be alternately directed towards rain gardens. The runoff reductions for the entire catchment ranged from 12.7% to 19.4% depending on the event considered. The maximum discharged volume reduction ranged from 13% to 62% and the maximum peak flow rate reduction ranged from 7% to 56%. Of concern is that in-sewer sediment resuspension is an important process to consider with regard to the efficacy of best management practices aimed at reducing extreme loads and concentrations. Rain gardens were less effective for large events, which are of greater importance for drinking water sources. These practices could increase peak instantaneous loads as a result of greater in-sewer resuspension during large events. Multiple interventions would be required to achieve the objectives of reducing the number, total volumes and peak contaminant loads of overflows upstream of drinking water intakes. Copyright © 2014 Elsevier B.V. All rights reserved.
Comparison of conventional rule based flow control with control processes based on fuzzy logic in a combined sewer system.

PubMed

Klepiszewski, K; Schmitt, T G

2002-01-01

While conventional rule based, real time flow control of sewer systems is in common use, control systems based on fuzzy logic have been used only rarely, but successfully. The intention of this study is to compare a conventional rule based control of a combined sewer system with a fuzzy logic control by using hydrodynamic simulation. The objective of both control strategies is to reduce the combined sewer overflow volume by an optimization of the utilized storage capacities of four combined sewer overflow tanks. The control systems affect the outflow of four combined sewer overflow tanks depending on the water levels inside the structures. Both systems use an identical rule base. The developed control systems are tested and optimized for a single storm event which affects heterogeneously hydraulic load conditions and local discharge. Finally the efficiencies of the two different control systems are compared for two more storm events. The results indicate that the conventional rule based control and the fuzzy control similarly reach the objective of the control strategy. In spite of the higher expense to design the fuzzy control system its use provides no advantages in this case.
Modelling sewer sediment deposition, erosion, and transport processes to predict acute influent and reduce combined sewer overflows and CO(2) emissions.

PubMed

Mouri, Goro; Oki, Taikan

2010-01-01

Understanding of solids deposition, erosion, and transport processes in sewer systems has improved considerably in the past decade. This has provided guidance for controlling sewer solids and associated acute pollutants to protect the environment and improve the operation of wastewater systems. Although measures to decrease combined sewer overflow (CSO) events have reduced the amount of discharged pollution, overflows continue to occur during rainy weather in combined sewer systems. The solution lies in the amount of water allotted to various processes in an effluent treatment system, in impact evaluation of water quality and prediction technology, and in stressing the importance of developing a control technology. Extremely contaminated inflow has been a serious research subject, especially in connection with the influence of rainy weather on nitrogen and organic matter removal efficiency in wastewater treatment plants (WWTP). An intensive investigation of an extremely polluted inflow load to WWTP during rainy weather was conducted in the city of Matsuyama, the region used for the present research on total suspended solid (TSS) concentration. Since the inflow during rainy weather can be as much as 400 times that in dry weather, almost all sewers are unsettled and overflowing when a rain event is more than moderate. Another concern is the energy consumed by wastewater treatment; this problem has become important from the viewpoint of reducing CO(2) emissions and overall costs. Therefore, while establishing a prediction technology for the inflow water quality characteristics of a sewage disposal plant is an important priority, the development of a management/control method for an effluent treatment system that minimises energy consumption and CO(2) emissions due to water disposal is also a pressing research topic with regards to the quality of treated water. The procedure to improve water quality must make use of not only water quality and biotic criteria, but also modelling systems to enable the user to link the effect of changes in urban sewage systems with specific quality, energy consumption, CO(2) emission, and ecological improvements of the receiving water.
Spatial variability of characteristics and origins of urban wet weather pollution in combined sewers.

PubMed

Kafi-Benyahia, M; Gromaire, M G; Chebbo, G

2005-01-01

An experimental on-site observatory of urban pollutant loads in combined sewers was created in the centre of Paris to quantify and characterise the dry and wet weather flow in relation to spatial scale. Eight rainfall events were studied from April 2003 to May 2004. Samples were analysed for suspended solids, organic matter, nitrogen and heavy metals. Results confirm the extent of wet weather pollution. They have shown the relative homogeneity of SS and organic matter characteristics from one urban catchment area to another. Two groups of heavy metals were identified. The first one concerns Cu, which has a higher concentration in wet weather flow (WWF) than in dry weather flow (DWF), and runoff. The second includes Cd, Pb and Zn, where higher concentrations were measured in urban runoff than in WWF and DWF. A first evaluation of contribution of wastewater, urban runoff and sewer deposit erosion sources to wet weather pollution was established and has highlighted the contribution of wastewater and sewer deposits to this pollution. However, it has shown that sewer deposit erosion remains an important source of wet weather pollution at different spatial scales.
Acoustic measurement and morphological features of organic sediment deposits in combined sewer networks.

PubMed

Carnacina, Iacopo; Larrarte, Frédérique; Leonardi, Nicoletta

2017-04-01

The performance of sewer networks has important consequences from an environmental and social point of view. Poor functioning can result in flood risk and pollution at a large scale. Sediment deposits forming in sewer trunks might severely compromise the sewer line by affecting the flow field, reducing cross-sectional areas, and increasing roughness coefficients. In spite of numerous efforts, the morphological features of these depositional environments remain poorly understood. The interface between water and sediment remains inefficiently identified and the estimation of the stock of deposit is frequently inaccurate. In part, this is due to technical issues connected to difficulties in collecting accurate field measurements without disrupting existing morphologies. In this paper, results from an extensive field campaign are presented; during the campaign a new survey methodology based on acoustic techniques has been tested. Furthermore, a new algorithm for the detection of the soil-water interface, and therefore for the correct esteem of sediment stocks is proposed. Finally, results in regard to bed topography, and morphological features at two different field sites are presented and reveal that a large variability in bed forms is present along sewer networks. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effect of the spatiotemporal variability of rainfall inputs in water quality integrated catchment modelling for dissolved oxygen concentrations

NASA Astrophysics Data System (ADS)

Moreno Ródenas, Antonio Manuel; Cecinati, Francesca; ten Veldhuis, Marie-Claire; Langeveld, Jeroen; Clemens, Francois

2016-04-01

Maintaining water quality standards in highly urbanised hydrological catchments is a worldwide challenge. Water management authorities struggle to cope with changing climate and an increase in pollution pressures. Water quality modelling has been used as a decision support tool for investment and regulatory developments. This approach led to the development of integrated catchment models (ICM), which account for the link between the urban/rural hydrology and the in-river pollutant dynamics. In the modelled system, rainfall triggers the drainage systems of urban areas scattered along a river. When flow exceeds the sewer infrastructure capacity, untreated wastewater enters the natural system by combined sewer overflows. This results in a degradation of the river water quality, depending on the magnitude of the emission and river conditions. Thus, being capable of representing these dynamics in the modelling process is key for a correct assessment of the water quality. In many urbanised hydrological systems the distances between draining sewer infrastructures go beyond the de-correlation length of rainfall processes, especially, for convective summer storms. Hence, spatial and temporal scales of selected rainfall inputs are expected to affect water quality dynamics. The objective of this work is to evaluate how the use of rainfall data from different sources and with different space-time characteristics affects modelled output concentrations of dissolved oxygen in a simplified ICM. The study area is located at the Dommel, a relatively small and sensitive river flowing through the city of Eindhoven (The Netherlands). This river stretch receives the discharge of the 750,000 p.e. WWTP of Eindhoven and from over 200 combined sewer overflows scattered along its length. A pseudo-distributed water quality model has been developed in WEST (mikedhi.com); this is a lumped-physically based model that accounts for urban drainage processes, WWTP and river dynamics for several pollutant typologies. Different rainfall products are tested: 1) Block kriging of a single reliable rain gauge, 2) Block kriging product from a network of 13 rain gauges and, 3) Universal block kriging with 13 rain gauges and KNMI weather radar estimates as a covariate. Different temporal accumulation levels are compared ranging from 10min to 1h. A geostatistical approach is used to allocate the prediction of the rainfall input in each of the urban hydrological units composing the model. The change in model performance is then assessed by contrasting it with dissolved oxygen monitoring data in a series of events.
Real-time Control of sewer pumps by using ControlNEXT to smooth inflow at Waste Water Treatment Plant Garmerwolde

NASA Astrophysics Data System (ADS)

van Heeringen, Klaas-Jan; van Nooijen, Ronald; Kooij, Kees; Postma, Bokke

2016-04-01

The Garmerwolde waste water treatment plant (WWTP) in the Groningen area of the Netherlands, receives waste water from a large area. That waste water is collected from many sewer systems and transported to the WWTP through pressurized pipes. The supply of waste water to the WWTP is relatively low and very irregular during dry-weather conditions, resulting in a random pattern of flows. This irregularity is the effect of the local control of the pumps, where the pumps are individually operated as an on/off control based on the water levels in the connected sewer system. The influent may change from zero to high values in a few minutes. The treatment processes at the WWTP are negatively influenced by this irregularity, which ends in high costs for energy and use of chemicals. The ControlNEXT central control system is used to control the 5 largest pump stations, such that the total inflow at the WWTP becomes much smoother. This results in a reduction of operational costs of about 10%. The control algorithm determines whether the actual condition is dry or wet, based on real-time radar precipitation images and the rainfall forecast product HiRLAM. All actual data is also collected and validated, like water levels, pump operations and pump availability. This data management is done using Delft-FEWS. If the situation is identified as "wet", the sewer systems are emptied as far as possible to create maximum storage. If the situation is "dry" (and of course there is a dead band between dry and wet), the pumps are operated such that the total inflow into the WWTP is smoothed. This is done with a Greedy algorithm, developed by Delft University of Technology. The algorithm makes a plan for the next 24 hours (as the daily inflow has a typical daily pattern) and generally stores some water volume in the sewer systems during the day to be able to continue operations during the night. The pumps are controlled with a time step of 5 minutes, where ControlNEXT manages the communication of pump operation setpoints to the SCADA system. In case of failing communication, backup procedures are programmed in the PLC of the pump stations. In that case the old on/off operation based on local water levels will be used. The system has been operational since January 2016 and has been monitored since then. In addition to monitoring the positive effect on the inflow at the WWTP, an important issue is the possible sedimentation in the sewer systems. This will be monitored too.
A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania

NASA Astrophysics Data System (ADS)

Boukhemacha, Mohamed Amine; Gogu, Constantin Radu; Serpescu, Irina; Gaitanaru, Dragos; Bica, Ioan

2015-05-01

Management of groundwater systems in urban areas is necessary and can be reliably performed by means of mathematical modeling combined with geospatial analysis. A conceptual approach for the study of urban hydrogeological systems is presented. The proposed approach is based on the features of Bucharest city (Romania) and can be adapted to other urban areas showing similar characteristics. It takes into account the interaction between groundwater and significant urban infrastructure elements that can be encountered in modern cities such as subway tunnels and water-supply networks, and gives special attention to the sewer system. In this respect, an adaptation of the leakage factor approach is proposed, which uses a sewer-system zoning function related to the conduits' location in the aquifer system and a sewer-conduits classification function related to their structural and/or hydraulic properties. The approach was used to elaborate a single-layered steady state groundwater flow model for a pilot zone of Bucharest city.

Impact of Redevelopment Projects on Waste Water Infrastructure

NASA Astrophysics Data System (ADS)

Bhave, Prashant; Rahate, Sarvesh

2018-05-01

In the last few decades there has been a tremendous increase in urban population globally. Metropolitan cities in India are experiencing rapid change in their population due to migration from rural to urban areas. Due to limited land Mumbai city is experiencing vertical growth in the form of redevelopment projects, signifying a change in population density. Wastewater collection systems greatly contribute to the cost of the overall municipal sewerage system. Present study is an attempt to understand the impact of the redevelopment activities on the wastewater infrastructure. Existing sewerage network of an urban area in Central Mumbai was redesigned and analysed for four different planning scenarios with Bentley's SewerGEM. Results have shown significant change in diameters of the conduits within the sewer network, thus making it inefficient by 13, 19, 31 and 42% with each changing scenario. The results and analysis derived from the study are significant with respect to the urban town planners, developing solutions in alleviating the rising problem of sewer overflows and the economic impact being caused.
Effects of sanitary sewers on ground-water levels and streams in Nassau and Suffolk Counties, New York; Part 3, development and application of southern Nassau County model

USGS Publications Warehouse

Reilly, T.E.; Buxton, H.T.

1985-01-01

By 1990, sanitary sewers in Nassau County Sewage Disposal Districts 2 and 3 and Suffolk County Southwest Sewer District will discharge to the ocean 140 cu ft of water per second that would otherwise be returned to the groundwater system through septic tanks and similar systems. To evaluate the effects of this loss on groundwater levels and streamflow, the U.S. Geological Survey developed a groundwater flow model that couples a fine-scale subregional model to a regional model of a larger scale. The regional model generates flux boundary conditions for the subregional model, and the subregional model provides detail in the area of concern. Results indicate that the water table will decline by as much as 90% from conditions in the early 1970's. This report is one of a three-part series describing the predicted hydrologic effects of sewers in southern Nassau and southwestern Suffolk Counties. (USGS)
Field data analysis of active chlorine-containing stormwater samples.

PubMed

Zhang, Qianyi; Gaafar, Mohamed; Yang, Rong-Cai; Ding, Chen; Davies, Evan G R; Bolton, James R; Liu, Yang

2018-01-15

Many municipalities in Canada and all over the world use chloramination for drinking water secondary disinfection to avoid DBPs formation from conventional chlorination. However, the long-lasting monochloramine (NH 2 Cl) disinfectant can pose a significant risk to aquatic life through its introduction into municipal storm sewer systems and thus fresh water sources by residential, commercial, and industrial water uses. To establish general total active chlorine (TAC) concentrations in discharges from storm sewers, the TAC concentration was measured in stormwater samples in Edmonton, Alberta, Canada, during the summers of 2015 and 2016 under both dry and wet weather conditions. The field-sampling results showed TAC concentration variations from 0.02 to 0.77 mg/L in summer 2015, which exceeds the discharge effluent limit of 0.02 mg/L. As compared to 2015, the TAC concentrations were significantly lower during the summer 2016 (0-0.24 mg/L), for which it is believed that the higher precipitation during summer 2016 reduced outdoor tap water uses. Since many other cities also use chloramines as disinfectants for drinking water disinfection, the TAC analysis from Edmonton may prove useful for other regions as well. Other physicochemical and biological characteristics of stormwater and storm sewer biofilm samples were also analyzed, and no significant difference was found during these two years. Higher density of AOB and NOB detected in the storm sewer biofilm of residential areas - as compared with other areas - generally correlated to high concentrations of ammonium and nitrite in this region in both of the two years, and they may have contributed to the TAC decay in the storm sewers. The NH 2 Cl decay laboratory experiments illustrate that dissolved organic carbon (DOC) concentration is the dominant factor in determining the NH 2 Cl decay rate in stormwater samples. The high DOC concentrations detected from a downstream industrial sampling location may contribute to a high stormwater NH 2 Cl decay rate in this area. Copyright © 2017 Elsevier Ltd. All rights reserved.
Required spatial resolution of hydrological models to evaluate urban flood resilience measures

NASA Astrophysics Data System (ADS)

Gires, A.; Giangola-Murzyn, A.; Tchiguirinskaia, I.; Schertzer, D.; Lovejoy, S.

2012-04-01

During a flood in urban area, several non-linear processes (rainfall, surface runoff, sewer flow, and sub-surface flow) interact. Fully distributed hydrological models are a useful tool to better understand these complex interactions between natural processes and man built environment. Developing an efficient model is a first step to improve the understanding of flood resilience in urban area. Given that the previously mentioned underlying physical phenomenon exhibit different relevant scales, determining the required spatial resolution of such model is tricky but necessary issue. For instance such model should be able to properly represent large scale effects of local scale flood resilience measures such as stop logs. The model should also be as simple as possible without being simplistic. In this paper we test two types of model. First we use an operational semi-distributed model over a 3400 ha peri-urban area located in Seine-Saint-Denis (North-East of Paris). In this model, the area is divided into sub-catchments of average size 17 ha that are considered as homogenous, and only the sewer discharge is modelled. The rainfall data, whose resolution is 1 km is space and 5 min in time, comes from the C-band radar of Trappes, located in the West of Paris, and operated by Météo-France. It was shown that the spatial resolution of both the model and the rainfall field did not enable to fully grasp the small scale rainfall variability. To achieve this, first an ensemble of realistic rainfall fields downscaled to a resolution of 100 m is generated with the help of multifractal space-time cascades whose characteristic exponents are estimated on the available radar data. Second the corresponding ensemble of sewer hydrographs is simulated by inputting each rainfall realization to the model. It appears that the probability distribution of the simulated peak flow exhibits a power-law behaviour. This indicates that there is a great uncertainty associated with small scale rainfall. Second we focus on a 50 ha catchment of this area and implement Multi-Hydro, a fully distributed urban hydrological model currently being developed at Ecole des Ponts ParisTech (El Tabach et al., 2009). The version used in this paper consists in an interactive coupling between a 2D model representing infiltration and surface runoff (TREX, Two dimensional Runoff, Erosion and eXport model, Velleux et al., 2011) and a 1D model of sewer networks (SWMM, Storm Water Management Model, Rossman, 2007). Spatial resolution ranging from 2 m to 50 m for land use, topography and rainfall are tested. A special highlight on the impact of small scales rainfall is done. To achieve this the previously mentioned methodology is implemented with rainfall fields downscaled to 10 m in space and 20 s in time. Finally, we will discuss the gains generated by the implementation of the fully distributed model.
Rapid sonic characterisation of sewer change and obstructions.

PubMed

Podd, F J; Ali, M T B; Horoshenkov, K V; Wood, A S; Tait, S J; Boot, J C; Long, R; Saul, A J

2007-01-01

This paper reports on the development of a low-cost, rapidly deployable sensor for surveying live sewers for blockages and structural failures. The anticipated cost is an order of magnitude lower than current techniques. The technology is based on acoustic normal model decomposition, The instrument emits short coded acoustic signals which are reflected from any sewer wall defect. The acoustic signals can be short Gaussian pulses or longer sinusoidal sweeps and pseudo-random noise. The processing algorithms used on the reflected signal can predict the extent and geometry of the pipe deformation, and the locations and approximate size of common blockages. The effect of the water level on the frequency of the fundamental mode has also been investigated. It is shown that the technique can be adapted to work reliably in relatively large 600 mm diameter sewer pipes.
Methodology for Identifying and Quantifying Metal Pollutant Sources in Storm Water Runoff

DTIC Science & Technology

2015-02-01

sanitary sewer are not viable options. In addition, visual inspections of the drainage areas have been insufficient in identifying and quantifying the...diverting the runoff into the sanitary sewer system, but the cost could exceed millions of dollars. Instead of capturing and treating all stormwater...Unknown Appears only if Building Siding is “metal” Roof Material roof_mat_d Built Up, Metal Panel, Asphalt, Fabric, Clay , Slate, Wood, Other
Effects Of Leaky Sewers On Groundwater Quality

NASA Astrophysics Data System (ADS)

Leschik, S.; Musolff, A.; Reinstorf, F.; Strauch, G.; Oswald, S. E.; Schirmer, M.

2007-12-01

The impact of urban areas on groundwater quality has become an emerging research field in hydrogeology. Urban subsurface infrastructures like sewer networks are often leaky, so untreated wastewater may enter the urban aquifer. The transport of wastewater into the groundwater is still not well understood under field conditions. In the research platform WASSER Leipzig (Water And Sewershed Study of Environmental Risk in Leipzig- Germany) the effects of leaky sewers on the groundwater quality are investigated. The research is focused on the occurrence and transport of so-called "xenobiotics" such as pharmaceuticals and personal care product additives. Xenobiotics may pose a threat on human health, but can also be considered a marker for an urban impact on water resources. A new test site was established in Leipzig to quantify mass fluxes of xenobiotics into the groundwater from a leaky sewer. Corresponding to the leaks which were detected by closed circuit television inspections, monitoring wells were installed up- and downstream of the sewer. Concentrations of eight xenobiotics (technical-nonylphenol, bisphenol-a, caffeine, galaxolide, tonalide, carbamazepine, phenazone, ethinylestradiol) obtained from first sampling programmes were found to be highly heterogeneous, but a relation between the position of the sampling points and the sewer could not be clearly identified. However, concentrations of sodium, chloride, potassium and nitrate increased significantly downstream of the sewer which may be due to wastewater exfiltration, since no other source is known on the water flowpath from the upstream to the downstream wells. Because of the highly heterogeneous spatial distribution of xenobiotics at the test site, a monitoring concept was developed comprising both high-resolution sampling and an integral approach to obtain representative average concentrations. Direct-push techniques were used to gain insight into the fine-scale spatial distribution of the target compounds. An integral pumping test was performed to determine the total xenobiotic mass fluxes along control planes down- and upstream of the leaky sewer. The new monitoring concept helped to obtain robust estimates of xenobiotic mass fluxes into the groundwater.
Simulating groundwater-induced sewer flooding

NASA Astrophysics Data System (ADS)

Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

2016-12-01

During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.
Impact of reduced water consumption on sulfide and methane production in rising main sewers.

PubMed

Sun, Jing; Hu, Shihu; Sharma, Keshab Raj; Bustamante, Heriberto; Yuan, Zhiguo

2015-05-01

Reduced water consumption (RWC), for water conservation purposes, is expected to change the wastewater composition and flow conditions in sewer networks and affect the in-sewer transformation processes. In this study, the impact of reduced water consumption on sulfide and methane production in rising main sewers was investigated. Two lab-scale rising main sewer systems fed with wastewater of different strength and flow rates were operated to mimic sewers under normal and RWC conditions (water consumption reduced by 40%). Sulfide concentration under the RWC condition increased by 0.7-8.0 mg-S/L, depending on the time of a day. Batch test results showed that the RWC did not change the sulfate-reducing activity of sewer biofilms, the increased sulfide production being mainly due to longer hydraulic retention time (HRT). pH in the RWC system was about 0.2 units lower than that in the normal system, indicating that more sulfide would be in molecular form under the RWC condition, which would result in increased sulfide emission to the atmosphere as confirmed by the model simulation. Model based analysis showed that the cost for chemical dosage for sulfide mitigation would increase significantly per unit volume of sewage, although the total cost would decrease due to a lower sewage flow. The dissolved methane concentration under the RWC condition was over two times higher than that under the normal flow condition and the total methane discharge was about 1.5 times higher, which would potentially result in higher greenhouse gas emissions. Batch tests showed that the methanogenic activity of sewer biofilms increased under the RWC condition, which along with the longer HRT, led to increased methane production. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sediment transport modeling in deposited bed sewers: unified form of May's equations using the particle swarm optimization algorithm.

PubMed

Safari, Mir Jafar Sadegh; Shirzad, Akbar; Mohammadi, Mirali

2017-08-01

May proposed two dimensionless parameters of transport (η) and mobility (F s ) for self-cleansing design of sewers with deposited bed condition. The relationships between those two parameters were introduced in conditional form for specific ranges of F s , which makes it difficult to use as a practical tool for sewer design. In this study, using the same experimental data used by May and employing the particle swarm optimization algorithm, a unified equation is recommended based on η and F s . The developed model is compared with original May relationships as well as corresponding models available in the literature. A large amount of data taken from the literature is used for the models' evaluation. The results demonstrate that the developed model in this study is superior to May and other existing models in the literature. Due to the fact that in May's dimensionless parameters more effective variables in the sediment transport process in sewers with deposited bed condition are considered, it is concluded that the revised May equation proposed in this study is a reliable model for sewer design.
Temporal asymmetry in precipitation time series and its influence on flow simulations in combined sewer systems

NASA Astrophysics Data System (ADS)

Müller, Thomas; Schütze, Manfred; Bárdossy, András

2017-09-01

A property of natural processes is temporal irreversibility. However, this property cannot be reflected by most statistics used to describe precipitation time series and, consequently, is not considered in most precipitation models. In this paper, a new statistic, the asymmetry measure, is introduced and applied to precipitation enabling to detect and quantify irreversibility. It is used to analyze two different data sets of Singapore and Germany. The data of both locations show a significant asymmetry for high temporal resolutions. The asymmetry is more pronounced for Singapore where the climate is dominated by convective precipitation events. The impact of irreversibility on applications is analyzed on two different hydrological sewer system models. The results show that the effect of the irreversibility can lead to biases in combined sewer overflow statistics. This bias is in the same order as the effect that can be achieved by real time control of sewer systems. Consequently, wrong conclusion can be drawn if synthetic time series are used for sewer systems if asymmetry is present, but not considered in precipitation modeling.
Hydrogeology and groundwater quality at monitoring wells installed for the Tunnel and Reservoir Plan System and nearby water-supply wells, Cook County, Illinois, 1995–2013

USGS Publications Warehouse

Kay, Robert T.

2016-04-04

Groundwater-quality data collected from 1995 through 2013 from 106 monitoring wells open to the base of the Silurian aquifer surrounding the Tunnel and Reservoir Plan (TARP) System in Cook County, Illinois, were analyzed by the U.S. Geological Survey, in cooperation with the Metropolitan Water Reclamation District of Greater Chicago, to assess the efficacy of the monitoring network and the effects of water movement from the tunnel system to the surrounding aquifer. Groundwater from the Silurian aquifer typically drains to the tunnel system so that analyte concentrations in most of the samples from most of the monitoring wells primarily reflect the concentration of the analyte in the nearby Silurian aquifer. Water quality in the Silurian aquifer is spatially variable because of a variety of natural and non-TARP anthropogenic processes. Therefore, the trends in analyte values at a given well from 1995 through 2013 are primarily a reflection of the spatial variation in the value of the analyte in groundwater within that part of the Silurian aquifer draining to the tunnels. Intermittent drainage of combined sewer flow from the tunnel system to the Silurian aquifer when flow in the tunnel systemis greater than 80 million gallons per day may affect water quality in some nearby monitoring wells. Intermittent drainage of combined sewer flow from the tunnel system to the Silurian aquifer appears to affect the values of electrical conductivity, hardness, sulfate, chloride, dissolved organic carbon, ammonia, and fecal coliform in samples from many wells but typically during less than 5 percent of the sampling events. Drainage of combined sewer flow into the aquifer is most prevalent in the downstream parts of the tunnel systems because of the hydraulic pressures elevated above background values and long residence time of combined sewer flow in those areas. Elevated values of the analytes emplaced during intermittent migration of combined sewer flow into the Silurian aquifer decrease through time as water from the aquifer drains back into the tunnels in response to typical hydraulic conditions. Of the analytes sampled, fecal coliform provides the clearest indication of the location and timing of combined sewer flow into the Silurian aquifer surrounding the tunnel system.
Interaction of coastal urban groundwater with infrastructure due to tidal variation

NASA Astrophysics Data System (ADS)

Su, X.; Prigiobbe, V.

2017-12-01

The urbanization of coastal areas has been increasing during the last century. For these areas, groundwater is one of major source of potable water for the population, the industry, and the agriculture, with an average demand of 30 m3/s [1,2]. Simultaneously, the rate of sea-level rise has been recorded to be approximately 40 mm/yr [3], with potential negative consequences on the coastal groundwater. As the sea-level rises, sea-water intrusion into potable aquifers may become more important [4] and the water table of the shallow aquifer underneath the coastal areas may rise [5]. Therefore, the water quality of the aquifer decreases and interaction between the shallow aquifer and infrastructure may occur. In particular, in the latter case, disruptive events may become more frequent, such as infiltration of groundwater into damaged sewer causing discharge of untreated sewage (combined sewer overflows, CSOs). Here, a study is presented on the modeling of urban groundwater in coastal areas to identify the cause of frequent CSOs in dry weather conditions, i.e., CSOs are not expected to occur. The evolution of the water table was described in response of tidal variation to quantify the interaction between the shallow aquifer and an aging sewer. The watershed of the city of Hoboken (NJ), at the estuary of Hudson river, was implemented in MODFLOW. The model was built using dataset from various sources. Geostatistic was applied to create the aquifer geology and measurements of the water table from monitoring wells within the urban area were used as boundary conditions and model validation. Preliminary results of the simulations are shown the figure, where the water table over a period of 7 months was calculated. The groundwater model with the sewer will help identifying the parts of the network that might be submerged by the groundwater and, therefore, subjected to infiltration. Combining groundwater and sewer modeling with the hydrograph separation method [6], the model prediction of infiltration will be validated. References [1] Pimentel et al. BioScience, 54, 909-918, 2004. [2] Owolabi Glob. Ini., 11, 69-87, 2017. [3] Milne Astro. Geophys., 49, 224-228, 2008 [4] Vzquez-Su et al. Hydro. J. 13, 522-533, 2005. [5] Gburek et al. Ground Water, 37,175-184, 1999. [6] Prigiobbe and Giulianelli. Water Sci.Tech. 60, 727-735, 2009.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Wade C.

Oak Ridge Institute for Science and Education (ORISE) personnel visited the United Nuclear Corporation (UNC) Naval Products site on three separate occasions during the months of October and November 2011. The purpose of these visits was to conduct confirmatory surveys of soils associated with the Argyle Street sewer line that was being removed. Soil samples were collected from six different, judgmentally determined locations in the Argyle Street sewer trench. In addition to the six soil samples collected by ORISE, four replicate soil samples were collected by Cabrera Services, Inc. (CSI) for analysis by the ORISE laboratory. Replicate samples S0010 andmore » S0011 were final status survey (FSS) bias samples; S0012 was an FSS systematic sample; and S0015 was a waste characterization sample. Six soil samples were also collected for background determination. Uranium-235 and uranium-238 concentrations were determined via gamma spectroscopy; the spectra were also reviewed for other identifiable photopeaks. Radionuclide concentrations for these soil samples are provided. In addition to the replicate samples and the samples collected by ORISE, CSI submitted three soil samples for inter-laboratory comparison analyses. One sample was from the background reference area, one was from waste characterization efforts (material inside the sewer line), and one was a FSS sample. The inter-laboratory comparison analyses results between ORISE and CSI were in agreement, except for one sample collected in the reference area. Smear results For Argyle Street sewer pipes are tabulated.« less
Contribution of Geographic Information Systems and location models to planning of wastewater systems.

PubMed

Leitão, J P; Matos, J S; Gonçalves, A B; Matos, J L

2005-01-01

This paper presents the contributions of Geographic Information Systems (GIS) and location models towards planning regional wastewater systems (sewers and wastewater treatment plants) serving small agglomerations, i.e. agglomerations with less than 2,000 inhabitants. The main goal was to develop a decision support tool for tracing and locating regional wastewater systems. The main results of the model are expressed in terms of number, capacity and location of Wastewater Treatment Plants (WWTP) and the length of main sewers. The decision process concerning the location and capacity of wastewater systems has a number of parameters that can be optimized. These parameters include the total sewer length and number, capacity and location of WWTP. The optimization of parameters should lead to the minimization of construction and operation costs of the integrated system. Location models have been considered as tools for decision support, mainly when a geo-referenced database can be used. In these cases, the GIS may represent an important role for the analysis of data and results especially in the preliminary stage of planning and design. After selecting the spatial location model and the heuristics, two greedy algorithms were implemented in Visual Basic for Applications on the ArcGIS software environment. To illustrate the application of these algorithms a case study was developed, in a rural area located in the central part of Portugal.
Tidal river sediments in the Washington, D.C. area. 1. Distribution and sources of trace metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Velinsky, D.J.; Wade, T.L.; Schlekat, C.E.

1994-06-01

Thirty-three bottom sediments were collected from the Potomac and Anacostia rivers, Tidal Basin, and Washington Ship Channel in June 1991 to define the extent of trace metal contamination and to elucidate source areas of sediment contaminants. In addition, twenty-three sediment samples were collected directly in front of and within major storm and combined sewers that discharge directly to these areas. Trace metals (e.g., Cu, Crk Cd, Hg, Pb, and Zn) exhibited a wide range in values in the study area. Sediment concentrations of Pb ranged from 32.0{mu}g Pb g {sup -1} to 3,630 {mu}g Pb g{sup -1}, Cd from 0.24more » {mu}g Cd g{sup -1} to 4.1 {mu}g Cd g{sup -1}, and Hg from 0.13 {mu}g g{sup -1} to 9.2 {mu}g Hg g{sup -1}, with generally higher concentrations in either outfall or sewer sediments compared to river bottom-sediments. In the Anacostia River measurements indicate that numerous storm and combined sewers are major sources of trace metals. Similar results were observed in both the Tidal Basin and Washington Ship Channel. Cadmium and Pb concentrations are higher in specific sewers and outfalls, whereas the distribution of other metals suggests a more diffuse source to the rivers and basins of the area. Cadmium and Pb also exhibited the greatest enrichment throughout the study area, with peak values in the Anacostia River, near the Washington Navy Yard. Enrichment factors decrease in the order: Cd>Pb>Zn>Hg>Cu>Cr. Between 70% and 96% of sediment-bound Pb and Cd was released from a N{sub 2}-purged 1N HCI leach. On average, {le}40% of total sedimentary Cu was liberated, possibly due to the partial attack of organic components of the sediment. Sediments of the tidal freshwater portion of the Potomac estuary reflect moderate to highly contaminated area with substantial enrichments of sedimentary Pb, Cd, and Zn. The sediment phase containing these metals indicates potential mobility of the sediment-bound metals during either storm events or dredging. 39 refs., 5 figs., 6 tabs.« less
Wastewater-Enhanced Microbial Corrosion of Concrete Sewers.

PubMed

Jiang, Guangming; Zhou, Mi; Chiu, Tsz Ho; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

2016-08-02

Microbial corrosion of concrete in sewers is known to be caused by hydrogen sulfide, although the role of wastewater in regulating the corrosion processes is poorly understood. Flooding and splashing of wastewater in sewers periodically inoculates the concrete surface in sewer pipes. No study has systematically investigated the impacts of wastewater inoculation on the corrosion of concrete in sewers. This study investigated the development of the microbial community, sulfide uptake activity, and the change of the concrete properties for coupons subjected to periodic wastewater inoculation. The concrete coupons were exposed to different levels of hydrogen sulfide under well-controlled conditions in laboratory-scale corrosion chambers simulating real sewers. It was evident that the periodic inoculation induced higher corrosion losses of the concrete in comparison to noninoculated coupons. Instantaneous measurements such as surface pH did not reflect the cumulative corrosion losses caused by long-term microbial activity. Analysis of the long-term profiles of the sulfide uptake rate using a Gompertz model supported the enhanced corrosion activity and greater corrosion loss. The enhanced corrosion rate was due to the higher sulfide uptake rates induced by wastewater inoculation, although the increasing trend of sulfide uptake rates was slower with wastewater. Increased diversity in the corrosion-layer microbial communities was detected when the corrosion rates were higher. This coincided with the environmental conditions of increased levels of gaseous H2S and the concrete type.
Efficacy of alpha-chlorhydrin in sewer rat control.

PubMed Central

Andrews, R. V.; Belknap, R. W.

1983-01-01

A single application of the male chemosterilant, alpha-chlorhydrin, to a problem sewer rat infestation resulted in reductions of rat numbers and distribution which was comparable to effects of warfarin baiting methods. Rat numbers were reduced by more than 85% by both methods. More rapid mortality and recruitment were evident for warfarin effects; the alpha-chlorhydrin treated population had a longer lag phase of growth so that reinfestation of sewer habitat to pre-treatment numbers, and distribution over a 40 square block area, required approximately 1.5-2 times longer after alpha-chlorhydrin treatment when compared with warfarin treatment. Comparisons of changes in rat densities in infested sewers following the two treatments indicate that recovery of warfarin treated populations is achieved by reproductive recruitment followed by dispersal while alpha-chlorhydrin treated populations recover by slower immigration and later reproductive recruitment. Alpha-chlorohydrin should be a useful addition to a limited arsenal of rat control agents because of its specificity for the Norway rat, its single dose effectiveness as a toxicant-chemosterilant, and its short environmental half-life. PMID:6644013
Surface wastewater in Samara and their impact on water basins as water supply sources

NASA Astrophysics Data System (ADS)

Strelkov, Alexander; Shuvalov, Mikhail; Gridneva, Marina

2017-10-01

The paper gives an overview of surface wastewater outlets in Samara through the rainwater sewer system into the Saratov water reservoir and the Samara river. The rainwater sewer system in Samara is designed and executed according to a separate scheme, except for the old part of the city, where surface run-off is dumped into the sewer system through siphoned drain. The rainwater system disposes of surface, drainage, industrial clean-contamined waters, emergency and technology discharges from the city’s heat supply and water supply systems. The effluent discharge is carried out by means of separate wastewater outlets into ravines or directly into the Samara river and the Saratov water reservoir without cleaning. The effluent discharge is carried out through the rainwater sewer system with 17 wastewater outlets into the Saratov water reservoir. In the Samara river, surface runoff drainage and clean-contamined water of industrial enterprises is carried out through 14 wastewater outlets. This study emphasizes the demand to arrange effluent discharge and construction of sewage treatment plants to prevent contamination of water objects by surface run-off from residential areas and industrial territories.
Environmental Impact Analysis Process. Environmental Assessment for Replacement Medical Clinic 61st Medical Squadron, Los Angeles Air Force Base

DTIC Science & Technology

1999-12-01

mass transit (buses, commuter trains and light rail ) serves Los Angeles County. Immediate public transit access to Los Angeles AFB is by bus only. 3.8...mostly paved. As a result, surface drainage enters the storm sewer system. Stormwater run-off from Area B of Los Angeles AFB, and specifically from...leaves the installation in the form of stormwater run-off. Little infiltration of rainfall is expected. 3.4 BIOLOGICAL RESOURCES As a result of the

Spatial and temporal resolution effects on urban catchments with different imperviousness degrees

NASA Astrophysics Data System (ADS)

Cristiano, Elena; ten Veldhuis, Marie-Claire; van de Giesen, Nick C.

2015-04-01

One of the main problems in urban hydrological analysis is to measure the rainfall at urban scale with high resolution and use these measurements to model urban runoff processes to predict flows and reduce flood risk. With the aim of building a semi-distribute hydrological sewer model for an urban catchment, high resolution rainfall data are required as input. In this study, the sensitivity of hydrological response to high resolution precipitation data for hydrodynamic models at urban scale is evaluated with different combinations of spatial and temporal resolutions. The aim is to study sensitivity in relation to catchment characteristics, especially drainage area size, imperviousness degree and hydraulic properties such as special structures (weirs, pumping stations). Rainfall data of nine storms are considered with 4 different spatial resolutions (3000m, 1000m, 500m and 100m) combined with 4 different temporal resolutions (10min, 5min, 3min and 1min). The dual polarimetric X-band weather radar, located in the Cabauw Experimental Site for Atmospheric Research (CESAR) provided the high resolution rainfall data of these rainfall events, used to improve the sewer model. The effects of spatial-temporal rainfall input resolution on response is studied in three Districts of Rotterdam (NL): Kralingen, Spaanse Polder and Centrum district. These catchments have different average drainage area size (from 2km2 to 7km2), and different general characteristics. Centrum district and Kralingen are, indeed, more various and include residential and commercial areas, big green areas and a small industrial area, while Spaanse Polder is a industrial area, densely urbanized, and presents a high percentage of imperviousness.
Transfer of glyphosate and its degradate AMPA to surface waters through urban sewerage systems.

PubMed

Botta, Fabrizio; Lavison, Gwenaëlle; Couturier, Guillaume; Alliot, Fabrice; Moreau-Guigon, Elodie; Fauchon, Nils; Guery, Bénédicte; Chevreuil, Marc; Blanchoud, Hélène

2009-09-01

A study of glyphosate and aminomethyl phosphonic acid (AMPA) transfer in the Orge watershed (France) was carried out during 2007 and 2008. Water samples were collected in surface water, wastewater sewer, storm sewer and wastewater treatment plant (WWTP). These two molecules appeared to be the most frequently detected ones in the rivers and usually exceeded the European quality standard concentrations of 0.1microg L(-1) for drinking water. The annual glyphosate estimated load was 1.9 kg year(-1) upstream (agricultural zone) and 179.5 kg year(-1) at the catchment outlet (urban zone). This result suggests that the contamination of this basin by glyphosate is essentially from urban origin (road and railway applications). Glyphosate reached surface water prevalently through storm sewer during rainfall event. Maximum concentrations were detected in storm sewer just after a rainfall event (75-90 microg L(-1)). High concentrations of glyphosate in surface water during rainfall events reflected urban runoff impact. AMPA was always detected in the sewerage system. This molecule reached surface water mainly via WWTP effluent and also through storm sewer. Variations in concentrations of AMPA during hydrological episodes were minor compared to glyphosate variations. Our study highlights that AMPA and glyphosate origins in urban area are different. During dry period, detergent degradation seemed to be the major AMPA source in wastewater.
Implication of climate change on urban drainage systems of Chicago and Mainstream and DesPlaines (MS/DP) Tunnel and Reservoir Plan (TARP)

NASA Astrophysics Data System (ADS)

Luo, H.; Schmidt, A.; Garcia, M. H.; Oberg, N.

2016-12-01

The impact of changing climate patterns and rainfall extremes on sewer system and river basin has been brought to attention to the researchers worldwide. In 1972, the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) adopted the Tunnel and Reservoir Plan (TARP) to address combined sewer overflow (CSO) pollution and flooding problems in the Chicago land area. The hydrosystem laboratory in University of Illinois at Urbana-Champaign developed a series of numerical models accordingly to analyze the complex hydraulic behavior of the as-built TARP system. Due to the interconnected nature of City of Chicago sewer network and MS/DP TARP system, a tightly coupled hydrological and hydraulic model MetroFlow was developed to facilitate such analysis by integrating previous developed models. This study utilized MetroFlow to predict the hydrologic/hydraulic response of the system for a set of pre-determined design and historical storm events. Accordingly, combined sewer overflows (CSO) of Chicago combined sewer system and MS/DP TARP system were evaluated under current and future weather scenarios. The total CSOs from TARP system can be considered as urban point pollution source to the surrounding receiving bodies, hence the potential impact of climate change on CSO fluxes is essential reference to wastewater infrastructure design and operations of the hydraulic regulating structures under storm events to mitigate predicted risks.
Application of Morphological Segmentation to Leaking Defect Detection in Sewer Pipelines

PubMed Central

Su, Tung-Ching; Yang, Ming-Der

2014-01-01

As one of major underground pipelines, sewerage is an important infrastructure in any modern city. The most common problem occurring in sewerage is leaking, whose position and failure level is typically idengified through closed circuit television (CCTV) inspection in order to facilitate rehabilitation process. This paper proposes a novel method of computer vision, morphological segmentation based on edge detection (MSED), to assist inspectors in detecting pipeline defects in CCTV inspection images. In addition to MSED, other mathematical morphology-based image segmentation methods, including opening top-hat operation (OTHO) and closing bottom-hat operation (CBHO), were also applied to the defect detection in vitrified clay sewer pipelines. The CCTV inspection images of the sewer system in the 9th district, Taichung City, Taiwan were selected as the experimental materials. The segmentation results demonstrate that MSED and OTHO are useful for the detection of cracks and open joints, respectively, which are the typical leakage defects found in sewer pipelines. PMID:24841247
Fault detection on a sewer network by a combination of a Kalman filter and a binary sequential probability ratio test

NASA Astrophysics Data System (ADS)

Piatyszek, E.; Voignier, P.; Graillot, D.

2000-05-01

One of the aims of sewer networks is the protection of population against floods and the reduction of pollution rejected to the receiving water during rainy events. To meet these goals, managers have to equip the sewer networks with and to set up real-time control systems. Unfortunately, a component fault (leading to intolerable behaviour of the system) or sensor fault (deteriorating the process view and disturbing the local automatism) makes the sewer network supervision delicate. In order to ensure an adequate flow management during rainy events it is essential to set up procedures capable of detecting and diagnosing these anomalies. This article introduces a real-time fault detection method, applicable to sewer networks, for the follow-up of rainy events. This method consists in comparing the sensor response with a forecast of this response. This forecast is provided by a model and more precisely by a state estimator: a Kalman filter. This Kalman filter provides not only a flow estimate but also an entity called 'innovation'. In order to detect abnormal operations within the network, this innovation is analysed with the binary sequential probability ratio test of Wald. Moreover, by crossing available information on several nodes of the network, a diagnosis of the detected anomalies is carried out. This method provided encouraging results during the analysis of several rains, on the sewer network of Seine-Saint-Denis County, France.
High resolution modelling of extreme precipitation events in urban areas

NASA Astrophysics Data System (ADS)

Siemerink, Martijn; Volp, Nicolette; Schuurmans, Wytze; Deckers, Dave

2015-04-01

The present day society needs to adjust to the effects of climate change. More extreme weather conditions are expected, which can lead to longer periods of drought, but also to more extreme precipitation events. Urban water systems are not designed for such extreme events. Most sewer systems are not able to drain the excessive storm water, causing urban flooding. This leads to high economic damage. In order to take appropriate measures against extreme urban storms, detailed knowledge about the behaviour of the urban water system above and below the streets is required. To investigate the behaviour of urban water systems during extreme precipitation events new assessment tools are necessary. These tools should provide a detailed and integral description of the flow in the full domain of overland runoff, sewer flow, surface water flow and groundwater flow. We developed a new assessment tool, called 3Di, which provides detailed insight in the urban water system. This tool is based on a new numerical methodology that can accurately deal with the interaction between overland runoff, sewer flow and surface water flow. A one-dimensional model for the sewer system and open channel flow is fully coupled to a two-dimensional depth-averaged model that simulates the overland flow. The tool uses a subgrid-based approach in order to take high resolution information of the sewer system and of the terrain into account [1, 2]. The combination of using the high resolution information and the subgrid based approach results in an accurate and efficient modelling tool. It is now possible to simulate entire urban water systems using extreme high resolution (0.5m x 0.5m) terrain data in combination with a detailed sewer and surface water network representation. The new tool has been tested in several Dutch cities, such as Rotterdam, Amsterdam and The Hague. We will present the results of an extreme precipitation event in the city of Schiedam (The Netherlands). This city deals with significant soil consolidation and the low-lying areas are prone to urban flooding. The simulation results are compared with measurements in the sewer network. References [1] Guus S. Stelling G.S., 2012. Quadtree flood simulations with subgrid digital elevation models. Water Management 165 (WM1):1329-1354. [2] Vincenzo Cassuli and Guus S. Stelling, 2013. A semi-implicit numerical model for urban drainage systems. International Journal for Numerical Methods in Fluids. Vol. 73:600-614. DOI: 10.1002/fld.3817
Nested 1D-2D approach for urban surface flood modeling

NASA Astrophysics Data System (ADS)

Murla, Damian; Willems, Patrick

2015-04-01

Floods in urban areas as a consequence of sewer capacity exceedance receive increased attention because of trends in urbanization (increased population density and impermeability of the surface) and climate change. Despite the strong recent developments in numerical modeling of water systems, urban surface flood modeling is still a major challenge. Whereas very advanced and accurate flood modeling systems are in place and operation by many river authorities in support of flood management along rivers, this is not yet the case in urban water management. Reasons include the small scale of the urban inundation processes, the need to have very high resolution topographical information available, and the huge computational demands. Urban drainage related inundation modeling requires a 1D full hydrodynamic model of the sewer network to be coupled with a 2D surface flood model. To reduce the computational times, 0D (flood cones), 1D/quasi-2D surface flood modeling approaches have been developed and applied in some case studies. In this research, a nested 1D/2D hydraulic model has been developed for an urban catchment at the city of Gent (Belgium), linking the underground sewer (minor system) with the overland surface (major system). For the overland surface flood modelling, comparison was made of 0D, 1D/quasi-2D and full 2D approaches. The approaches are advanced by considering nested 1D-2D approaches, including infiltration in the green city areas, and allowing the effects of surface storm water storage to be simulated. An optimal nested combination of three different mesh resolutions was identified; based on a compromise between precision and simulation time for further real-time flood forecasting, warning and control applications. Main streets as mesh zones together with buildings as void regions constitute one of these mesh resolution (3.75m2 - 15m2); they have been included since they channel most of the flood water from the manholes and they improve the accuracy of interactions within the 1D sewer network. Other areas that recorded flooding outside the main streets have been also included with the second mesh resolution for an accurate determination of flood maps (12.5m2 - 50m2). Permeable areas have been identified and used as infiltration zones using the Horton infiltration model. A mesh sensitivity analysis has been performed for the low flood risk areas for a proper model optimization. As outcome of that analysis, the third mesh resolution has been chosen (75m2 - 300m2). Performance tests have been applied for several synthetic design storms as well as historical storm events displaying satisfactory results upon comparing the flood mapping outcomes produced by the different approaches. Accounting for the infiltration in the green city spaces reduces the flood extents in the range 39% - 68%, while the average reduction in flood volume equals 86%. Acknowledgement: Funding for this research was provided by the Interreg IVB NWE programme (project RainGain) and the Belgian Science Policy Office (project PLURISK). The high resolution topographical information data were obtained from the geographical information service AGIV; the original full hydrodynamic sewer network model from the service company Farys, and the InfoWorks licence from Innovyze.
COMBINED-SEWER OVERFLOW CONTROL AND TREATMENT

EPA Science Inventory

Combined-sewer overflow (CSO), along with sanitary-sewer overflow and stormwater are significant contributors of contamination to surface waters. During a rain event, the flow in a combined sewer system may exceed the capacity of the intercepting sewer leading to the wastewater t...
Integration of sewer system maps in topographically based sub-basin delineation in suburban areas

NASA Astrophysics Data System (ADS)

Jankowfsky, Sonja; Branger, Flora; Braud, Isabelle; Rodriguez, Fabrice

2010-05-01

Due to the increase of urbanization, suburban areas experience a fast change in land use. The impact of such modifications on the watershed hydrological cycle must be quantified. To achieve this goal, distributed hydrological models offer the possibility to take into account land use change, and more particularly to consider urbanized areas and anthropogenic features such as roads or ditches and their impact on the hydrological cycle. A detailed definition of the hydrographical drainage network and a corresponding delineation of sub-basins is therefore necessary as input to distributed models. Sub-basins in natural catchments are usually delineated using standard GIS based terrain analysis. The drainage network in urbanised watersheds is often modified, due to sewer systems, ditches, retention basins, etc.. Therefore, its delineation is not only determined by topography. The simple application of terrain analysis algorithms to delineate sub-basins in suburban areas can consequently lead to erroneous sub-basin borders. This study presents an improved approach for sub-basin delineation in suburban areas. It applies to small catchments connected to a sewage plant, located outside the catchment boundary. The approach assumes that subsurface flow follows topography. The method requires a digital elevation model (DEM), maps of land use, cadastre, sewer system and the location of measurement stations and retention basins. Firstly, the topographic catchment border must be defined for the concerning flow measurement station. Standard GIS based algorithms, like the d8-flow direction algorithm (O'Callaghan and Mark, 1984) can be applied using a high resolution DEM. Secondly, the artificial catchment outlets have to be determined. Each catchment has one natural outlet - the measurement station on the river- but it can have several artificial outlets towards a sewage station. Once the outlets are determined, a first approximation of the "theoretical maximal contributing area" can be made. It encompasses the whole connected sewer system and the topographic catchment boundary. The area of interest is therefore defined. The next step is the determination of the extended drainage network, consisting of the natural river, ditches, combined and separated sewer systems and retention basins. This requires a detailed analysis of sewer system data, field work (mapping of ditches and inlets into the natural river). Contacts with local authorities are also required to keep up-to-date about recent changes. Pure wastewater and drinking water pipes are not integrated in the drainage network. In order to have a unique drainage network for the model, choices might have to be made in case of several coexisting drainage pipes. The urban sub-basins are then delineated with the help of a cadastral map (Rodriguez et al., 2003) or an aerial photography. Each cadastral unit is connected to the closest drainage pipe, following the principle of proximity and gravity. The assembly of all cadastral units connected to one network reach represents one urban sub-basin. The sub-basins in the rural part are calculated using the d8 flow direction and watershed delineation algorithm with "stream burning" (Hutchinson, 1989). One sub-basin is delineated for each reach of the extended drainage network. Some manual corrections of the calculated sub-basins are necessary. Finally, the urban and rural sub-basins are merged by subtraction of the urban area from the rural area and subsequent union of both maps. This method was applied to the Chaudanne catchment, a sub-basin of the Yzeron catchment (ca. 4 km2) in the suburban region of Lyon city, France. The method leads to a 30 % extended catchment area, as compared to the topographic catchment area. For each river inlet the sub-basin area could be determined, as well as for each retention basin. This information can be directly used for the dimensioning of retention basins, pipe diameters, etc.
Selective inspection planning with ageing forecast for sewer types.

PubMed

Baur, R; Herz, R

2002-01-01

Investments in sewer rehabilitation must be based on inspection and evaluation of sewer conditions with respect to the severity of sewer damage and to environmental risks. This paper deals with the problems of forecasting the condition of sewers in a network from a small sample of inspected sewers. Transition functions from one into the next poorer condition class, which were empirically derived from this sample, are used to forecast the condition of sewers. By the same procedure, transition functions were subsequently calibrated for sub-samples of different types of sewers. With these transition functions, the most probable date of entering a critical condition class can be forecast from sewer characteristics, such as material, period of construction, location, use for waste and/or storm water, profile, diameter and gradient. Results are shown for the estimates about the actual condition of the Dresden sewer network and its deterioration in case of doing nothing about it. A procedure is proposed for scheduling the inspection dates for sewers which have not yet been inspected and for those which have been inspected before.
Molecular detection of pathogenic leptospiral protein encoding gene (lipL32) in environmental aquatic biofilms.

PubMed

Vinod Kumar, K; Lall, C; Vimal Raj, R; Vedhagiri, K; Vijayachari, P

2016-04-01

Leptospirosis is a zoonotic disease often encountered during post-monsoon season due to exposure with contaminated water. Leptospires have long been regarded as solitary organisms that persist in soil and aquatic environments. Here, the presence of leptospires in the aquatic biofilm exposed in the paddy field, sewers and stagnant rain water was demonstrated. Biofilm samples from paddy field water, submerged paddy leaves, sewers and stagnant rain waters from urban and rural areas were collected. Total genomic DNA was extracted and pathogenic leptospiral specific gene amplification was carried out to determine the spatial distribution of the bacteria. The degree of pathogenic Leptospira in biofilms from paddy field surface water, submerged leaf, were 33·3% and 27·2% respectively, whereas in rural and urban area, the sampling sites such as stagnant rain water, domestic sewer and collective sewers showed 11·1%, 13% and 16·6% with leptospires respectively. Higher proportion of pathogenic Leptospira in aquatic ecosystems, such as paddy field, could be one of the main factors for the occurrence of disease, more among the agricultural workers. This study would help to identify various survival strategies of leptospires in the environment and thus disease transmission. Little is known regarding the mechanisms by which pathogenic leptospires persist in aqueous environment, outside the mammalian host. In this view this is the first report of the distribution of Leptospira in environmental biofilm such as sewers and paddy leaf surfaces. This ability of pathogenic Leptospira to survive in aquatic ecosystems especially in biofilms could be one of the main factors which facilitate its survival in the environment, and thus disease transmission among the risk groups, such as sewage and agriculture worker. This study will encourage researchers in the field to consider biofilm as an important factor, when detecting leptospires in environment. © 2015 The Society for Applied Microbiology.
Hydrologic data for urban stormwater studies in the Dallas-Fort Worth area, Texas, 1992-94

USGS Publications Warehouse

Baldys, Stanley; Raines, T.H.; Mansfield, B.L.; Sandlin, J.T.

1997-01-01

This report presents precipitation and waterquality data from analyses of 210 samples collected at 30 storm-sewer outfall stations in the Dallas-Fort Worth area, Texas, during February 1992-November 1994. The data were collected to fulfill requirements mandated by the U.S. Environmental Protection Agency to the cities of Arlington, Dallas, Fort Worth, Garland, Irving, Mesquite, and Piano and to the Dallas and Fort Worth Districts of the Texas Department of Transportation to obtain a National Pollution Discharge Elimination System permit. Data were collected at storm-sewer outfall stations in drainage basins classified as singular land use, either residential, commercial, industrial, or highway. Also included are qualityassurance/quality-control data for samples collected in conjunction with the stormwater samples.
A Multi-Hydro simulation for evaluation of the impacts of flood management at Heywood, RU.

NASA Astrophysics Data System (ADS)

Giangola-Murzyn, Agathe; Richard, Julien; Hennermann, Karl; Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel

2013-04-01

The flooding problems in urban and peri-urban areas have more and more important impacts on city life. Indeed, with the expansion of the latter, the floodplains are more intensively used and floods will generate significant damage very expensive. In the aim to reduce these costs and facilitate a return to normal faster after the flood, the FP7 SMARTeST project aims to provide users of these areas a guide to help them choose the most appropriate protection measures. It is in this context that the Multi-Hydro model has been developed and improved in the Ecole des Ponts ParisTech. This model consists into a coupling between four modules (relying on existing open source and widely validated physically based model): one for the rainfall scenario generation, one for the surface processes, one for the subsurface processes and one for the load of the sewer system. This structure of coupling allows to represent all the parts of the water's path from the surface to the sewer system's pipes and to the soil of the considered catchment and it allows to disconnect one element of the coupling system if it's necessary. Moreover, this model uses some GIS data as the elevation, the land use, the soil description and the sewer system description which can be managed by a dedicated open source SIG allowing to use directly the data in the model. The Multi-Hydro model has been used on a street of Heywood, Rochdale, Greater Manchester urban area. This residential street has known some important events during this last 10 years. Thus, Multi-Hydro has been used to evaluate the effects of the implementation of protection measures supposed to reduce the damages of the flood: a storage basin, located between Wilton Grove and the Egerton street and two barriers across the streets. For a given event, NIMROD radar data have been used to reproduce the flood. Then, the protective measures were put in place virtually. Analysis of water height maps obtained with Multi-Hydro allowed better understand and better assess the hydrological behavior of étidié neighborhood. Thus, the early assumptions about the location of the barriers have proved misguided. The results and the multiplication of the protection scenarios could thus permit to improve protection strategy in the studied streets.
PLANNING FOR SSO CONTROL: HENRICO COUNTY, VA - CASE STUDY

EPA Science Inventory

The nation's sanitary-sewer infrastructure is aging with some sewers over 100 years. There are more than 19,500 municipal sanitary-sewer collecton systems nationwide serving 150M people comprising 500,000 sewer miles. About 40,000 sanitary-sewer overflow (SSO) events nationwide y...
Risk assessment of sewer condition using artificial intelligence tools: application to the SANEST sewer system.

PubMed

Sousa, V; Matos, J P; Almeida, N; Saldanha Matos, J

2014-01-01

Operation, maintenance and rehabilitation comprise the main concerns of wastewater infrastructure asset management. Given the nature of the service provided by a wastewater system and the characteristics of the supporting infrastructure, technical issues are relevant to support asset management decisions. In particular, in densely urbanized areas served by large, complex and aging sewer networks, the sustainability of the infrastructures largely depends on the implementation of an efficient asset management system. The efficiency of such a system may be enhanced with technical decision support tools. This paper describes the role of artificial intelligence tools such as artificial neural networks and support vector machines for assisting the planning of operation and maintenance activities of wastewater infrastructures. A case study of the application of this type of tool to the wastewater infrastructures of Sistema de Saneamento da Costa do Estoril is presented.
24. The 184B Power House under construction, viewed to the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. The 184-B Power House under construction, viewed to the northeast in March 1944. The sewer line exiting to the Columbia river was used mainly for effluents from back-washing the filter basins. A separate Process Sewer Line (out of the picture to the right) for cooling water leaving the pile went to the 107-B Retention Basin, and ultimately to the river. P-1881 - B Reactor, Richland, Benton County, WA
From mess to mass: a methodology for calculating storm event pollutant loads with their uncertainties, from continuous raw data time series.

PubMed

Métadier, M; Bertrand-Krajewski, J-L

2011-01-01

With the increasing implementation of continuous monitoring of both discharge and water quality in sewer systems, large data bases are now available. In order to manage large amounts of data and calculate various variables and indicators of interest it is necessary to apply automated methods for data processing. This paper deals with the processing of short time step turbidity time series to estimate TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) event loads in sewer systems during storm events and their associated uncertainties. The following steps are described: (i) sensor calibration, (ii) estimation of data uncertainties, (iii) correction of raw data, (iv) data pre-validation tests, (v) final validation, and (vi) calculation of TSS and COD event loads and estimation of their uncertainties. These steps have been implemented in an integrated software tool. Examples of results are given for a set of 33 storm events monitored in a stormwater separate sewer system.
Development of a semi-automated model identification and calibration tool for conceptual modelling of sewer systems.

PubMed

Wolfs, Vincent; Villazon, Mauricio Florencio; Willems, Patrick

2013-01-01

Applications such as real-time control, uncertainty analysis and optimization require an extensive number of model iterations. Full hydrodynamic sewer models are not sufficient for these applications due to the excessive computation time. Simplifications are consequently required. A lumped conceptual modelling approach results in a much faster calculation. The process of identifying and calibrating the conceptual model structure could, however, be time-consuming. Moreover, many conceptual models lack accuracy, or do not account for backwater effects. To overcome these problems, a modelling methodology was developed which is suited for semi-automatic calibration. The methodology is tested for the sewer system of the city of Geel in the Grote Nete river basin in Belgium, using both synthetic design storm events and long time series of rainfall input. A MATLAB/Simulink(®) tool was developed to guide the modeller through the step-wise model construction, reducing significantly the time required for the conceptual modelling process.
Rainwater drainage management for urban development based on public-private partnership.

PubMed

Matsushita, J; Ozaki, M; Nishimura, S; Ohgaki, S

2001-01-01

The Urban Development Corporation (UDC) is one of the biggest implementation bodies for urban development in Japan. UDC has developed rainwater infiltration technology since 1975. This technology has effectively reduced runoff to a river and sewer system in the new town project areas. Recently, UDC has developed a new system which is defined as a "Rainwater Recycle Sewer System", which is supported by "Rainwater Storage and Infiltration Technology (RSIT)" applicable to new town creation and urban renewal. The new system consists of two elements: RSIT components based on Public-Private Partnership (PPP) and a stormwater drainage system. Herein, the private sector is responsible for the main part of RSIT, and the public sector is responsible for the stormwater drainage from the development area. As a result, the capacity of public facilities, such as rainwater sewers and stormwater reservoirs, can be reduced effectively. In parallel, the initial/running cost of public facilities is expected to be reduced. In conclusion, the authors would stress the importance of a co-maintenance system also based on PPP, which will be required especially in order to properly operate the whole system for the long term.
Advances in Sewer Condition and Capacity Assessment – Development and Applications of EPA SSOAP Toolbox

EPA Science Inventory

In the United States, sanitary sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) ev...

U.S. EPA Issues Technical Guides and Computer Tools for Sewer Condition and Capacity Assessment

EPA Science Inventory

The nation's sanitary sewer infrastructure is aging, with some sewers more than100 years old. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events per year...
Evidence of a sewer vapor transport pathway at the USEPA ...

EPA Pesticide Factsheets

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into the duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. These test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope. Highlights • The sewer line is an important pathway for VOC transport at the USEPA duplex. • The importance of this pathway was not identified during prior study of the duplex. • Sewer lines should be routinely evaluated
Use of pharmaceuticals and pesticides to constrain nutrient sources in coastal groundwater of northwestern Long Island, New York, USA

USGS Publications Warehouse

Zhao, S.; Zhang, P.; Crusius, John; Kroeger, K.D.; Bratton, J.F.

2011-01-01

In developed, non-agricultural, unsewered areas, septic systems and fertilizer application to lawns and gardens represent two major sources of nitrogen to coastal groundwater, in addition to atmospheric input. This study was designed to distinguish between these two possible nitrogen sources by analyzing groundwater samples for pharmaceutical residuals, because fertilizers do not contain any of these pharmaceuticals, but domestic wastewater commonly does. In addition, several herbicides and insecticides used in lawn treatment were analyzed as indicators of nitrogen delivery to groundwater from fertilizers. Groundwater samples were taken through piezometres at shoreline sites in unsewered areas surrounding Northport Harbor and in sewered areas adjacent to Manhasset Bay (hereafter referred to as "Northport" and "Manhasset", respectively), both in northwestern Long Island, USA. Excessive nitrogen loading has led to reduced dissolved oxygen concentrations in Long Island Sound, and the groundwater contribution to the nitrogen budget is poorly constrained. The frequent detection of the anticonvulsant compound carbamazepine in groundwater samples of the Northport Harbor area (unsewered), together with the fact that few pesticides associated with lawn applications were detected, suggests that wastewater input and atmospheric input are the likely sources of nitrogen in the Northport groundwater. High concentrations of nitrogen were also detected in the Manhasset (sewered) groundwater. The low detection frequency and concentration of carbamazepine, however, suggest that the sewer system effectively intercepts nitrogen from wastewater there. The likely sources of nitrogen in the Manhasset groundwater are atmospheric deposition and lawn fertilizers, as this area is densely populated.
NPDES Permits for Phase 2 Stormwater Program in Puerto Rico

EPA Pesticide Factsheets

EPA's 1999 stormwater Phase II regulations established small municipal separate storm sewer systems (MS4s) in urbanized areas, and small MS4s outside the urbanized areas that are designated by the permitting authority, to obtain NPDES permit coverage.
40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...
40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...
40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...
40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...
Locations of Combined Sewer Overflow Outfalls - US EPA Region 3

EPA Pesticide Factsheets

This data layer identifies the locations of Combined sewer overflow outfalls. Combined sewer systems are sewers that are designed to collect rainwater runoff, domestic sewage, and industrial wastewater in the same pipe. Most of the time, combined sewer systems transport all of their wastewater to a sewage treatment plant, where it is treated and then discharged to a water body. During periods of heavy rainfall or snowmelt, however, the wastewater volume in a combined sewer system can exceed the capacity of the sewer system or treatment plant. For this reason, combined sewer systems are designed to overflow occasionally and discharge excess untreated wastewater directly to nearby streams, rivers, or other water bodies. For further information visit: http://cfpub1.epa.gov/npdes/home.cfm?program_id=5
Water Quality of Combined Sewer Overflows, Stormwater, and Streams, Omaha, Nebraska, 2006-07

USGS Publications Warehouse

Vogel, Jason R.; Frankforter, Jill D.; Rus, David L.; Hobza, Christopher M.; Moser, Matthew T.

2009-01-01

The U.S. Geological Survey, in cooperation with the City of Omaha, investigated the water quality of combined sewer overflows, stormwater, and streams in the Omaha, Nebraska, area by collecting and analyzing 1,175 water samples from August 2006 through October 2007. The study area included the drainage area of Papillion Creek at Capeheart Road near Bellevue, Nebraska, which encompasses the tributary drainages of the Big and Little Papillion Creeks and Cole Creek, along with the Missouri River reach that is adjacent to Omaha. Of the 101 constituents analyzed during the study, 100 were detected in at least 1 sample during the study. Spatial and seasonal comparisons were completed for environmental samples. Measured concentrations in stream samples were compared to water-quality criteria for pollutants of concern. Finally, the mass loads of water-quality constituents in the combined sewer overflow discharges, stormwater outfalls, and streams were computed and compared. The results of the study indicate that combined sewer overflow and stormwater discharges are affecting the water quality of the streams in the Omaha area. At the Papillion Creek Basin sites, Escherichia coli densities were greater than 126 units per 100 milliliters in 99 percent of the samples (212 of 213 samples analyzed for Escherichia coli) collected during the recreational-use season from May through September (in 2006 and 2007). Escherichia coli densities in 76 percent of Missouri River samples (39 of 51 samples) were greater than 126 units per 100 milliliters in samples collected from May through September (in 2006 and 2007). None of the constituents with human health criteria for consumption of water, fish, and other aquatic organisms were detected at levels greater than the criteria in any of the samples collected during this study. Total phosphorus concentrations in water samples collected in the Papillion Creek Basin were in excess of the U.S. Environmental Protection Agency's proposed criterion in all but four stream samples (266 of 270). Similarly, only 2 of 84 Missouri River samples had total phosphorus concentrations less than the proposed criterion. The proposed total nitrogen criterion for the Corn Belt and Northern Great Plains ecoregion was surpassed in 80 percent of the water samples collected from the stream sites. Samples with total nitrogen concentrations greater than the proposed criterion were most common at Papillion Creek and Big Papillion Creek sites, where the proposed criterion was surpassed in 90 and 96 percent of the samples collected, respectively. Elevated concentrations of total nitrogen were less common at the Missouri River sites, with 33 percent of the samples analyzed having concentrations that surpassed the proposed nutrient criterion for total nitrogen. The three constituents with measured concentrations greater than their respective health-based screening levels were nickel, zinc, and dichlorvos. Differences in water quality during the beginning, middle, and end of the combined sewer overflow discharge and the stream hydrograph rise, peak, and recession were investigated. Concentrations from the ending part of the combined sewer overflow hydrograph were significantly different than those from the beginning and middle parts for 3 and 11 constituents, respectively. No constituents were significantly different between the beginning and middle parts of the combined sewer overflow discharge hydrograph. For the stream site upstream from combined sewer overflow outfalls on Cole Creek, the constituents with geometric mean values for the hydrograph rise that were at least twice those for the values of the peak and recession were specific conductance, magnesium, nitrite, N,N-diethyl-meta-toluamide (DEET), methyl salicylate, p-cresol, and Escherichia coli. Similarly, the constituents where the hydrograph peak was at least twice that for the rise and recession at the upstream Cole Creek site were total suspended solids, silver, an
Impact of toxic chemicals on local wastewater treatment plant and the environment

NASA Astrophysics Data System (ADS)

Bennett, Gary F.

1989-05-01

Because toxic chemicals being discharged to sewers were simultaneously interfering with wastewater treatment processes of municipal, biological treatment plants and were passing through these plants to negatively impact the bodies of water to which these plants were discharging, the U.S. Environmental Protection Agency issued regulations governing industrial discharges to municipal sewers. These “Pretreatment Regulations” limit industrial discharges to municipal sewers of heavy metals, oil and grease, acids and bases, and toxic organic chemicals. This paper discusses the evolution of these regulations, the basis for them, the types of regulations (categorical and local), and the rationale for their promulgation based on the impacts of toxics chemicals on the treatment plant and receiving system. Finally, the expected results of these regulations in reducing industrial discharges of toxic chemicals is discussed.
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex.

PubMed

McHugh, Thomas; Beckley, Lila; Sullivan, Terry; Lutes, Chris; Truesdale, Robert; Uppencamp, Rob; Cosky, Brian; Zimmerman, John; Schumacher, Brian

2017-11-15

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into the duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. These test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope. Copyright © 2017 Elsevier B.V. All rights reserved.
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

DOE PAGES

McHugh, Thomas; Beckley, Lila; Sullivan, Terry; ...

2017-04-26

We report the role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into themore » duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. Finally, these test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope.« less
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

DOE Office of Scientific and Technical Information (OSTI.GOV)

McHugh, Thomas; Beckley, Lila; Sullivan, Terry

We report the role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into themore » duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. Finally, these test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope.« less
IET control building (TAN620). interior service area. equipment on concrete ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET control building (TAN-620). interior service area. equipment on concrete pads. liquid pump and valves on right. control panel at center of view, blower at left. piping for vent and sanitary sewer. INEEL negative no. HD-21-3-1 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID
Storm Water Management Model (SWMM)

EPA Pesticide Factsheets

EPA's Storm Water Management Model (SWMM) is used throughout the world for planning, analysis and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas.
OPTIMIZING STORMWATER MANAGEMENT RETROFITS BASED ON IMPERVIOUS SURFACE CONNECTIONS TO SEWERS

EPA Science Inventory

Although total impervious area (TIA) is often used as an indicator of urban disturbance, recent studies suggest that the subset of impervious surfaces that route stormwater runoff directly to streams via stormwater pipes, called directly connected impervious area (DCIA), may be a...
Evaluation of a mass-balance approach to determine consumptive water use in northeastern Illinois

USGS Publications Warehouse

Mills, Patrick C.; Duncker, James J.; Over, Thomas M.; Marian Domanski,; ,; Engel, Frank

2014-01-01

Under ideal conditions, accurate quantification of consumptive use at the sewershed scale by the described mass-balance approach might be possible. Under most prevailing conditions, quantification likely would be more costly and time consuming than that of the present study, given the freely contributed technical support of the host community and relatively appropriate conditions of the study area. Essentials to quantification of consumptive use are a fully cooperative community, storm and sanitary sewers that are separate, and newer sewer infrastructure and (or) a robust program for limiting infiltration, exfiltration, and inflow.
Which downscaled rainfall data for climate change impact studies in urban areas? Review of current approaches and trends

NASA Astrophysics Data System (ADS)

Gooré Bi, Eustache; Gachon, Philippe; Vrac, Mathieu; Monette, Frédéric

2017-02-01

Changes in extreme precipitation should be one of the primary impacts of climate change (CC) in urban areas. To assess these impacts, rainfall data from climate models are commonly used. The main goal of this paper is to report on the state of knowledge and recent works on the study of CC impacts with a focus on urban areas, in order to produce an integrated review of various approaches to which future studies can then be compared or constructed. Model output statistics (MOS) methods are increasingly used in the literature to study the impacts of CC in urban settings. A review of previous works highlights the non-stationarity nature of future climate data, underscoring the need to revise urban drainage system design criteria. A comparison of these studies is made difficult, however, by the numerous sources of uncertainty arising from a plethora of assumptions, scenarios, and modeling options. All the methods used do, however, predict increased extreme precipitation in the future, suggesting potential risks of combined sewer overflow frequencies, flooding, and back-up in existing sewer systems in urban areas. Future studies must quantify more accurately the different sources of uncertainty by improving downscaling and correction methods. New research is necessary to improve the data validation process, an aspect that is seldom reported in the literature. Finally, the potential application of non-stationarity conditions into generalized extreme value (GEV) distribution should be assessed more closely, which will require close collaboration between engineers, hydrologists, statisticians, and climatologists, thus contributing to the ongoing reflection on this issue of social concern.
Simulation of the wastewater temperature in sewers with TEMPEST.

PubMed

Dürrenmatt, David J; Wanner, Oskar

2008-01-01

TEMPEST is a new interactive simulation program for the estimation of the wastewater temperature in sewers. Intuitive graphical user interfaces assist the user in managing data, performing calculations and plotting results. The program calculates the dynamics and longitudinal spatial profiles of the wastewater temperature in sewer lines. Interactions between wastewater, sewer air and surrounding soil are modeled in TEMPEST by mass balance equations, rate expressions found in the literature and a new empirical model of the airflow in the sewer. TEMPEST was developed as a tool which can be applied in practice, i.e., it requires as few input data as possible. These data include the upstream wastewater discharge and temperature, geometric and hydraulic parameters of the sewer, material properties of the sewer pipe and surrounding soil, ambient conditions, and estimates of the capacity of openings for air exchange between sewer and environment. Based on a case study it is shown how TEMPEST can be applied to estimate the decrease of the downstream wastewater temperature caused by heat recovery from the sewer. Because the efficiency of nitrification strongly depends on the wastewater temperature, this application is of practical relevance for situations in which the sewer ends at a nitrifying wastewater treatment plant.

Biodegradability of organic matter associated with sewer sediments during first flush.

PubMed

Sakrabani, Ruben; Vollertsen, Jes; Ashley, Richard M; Hvitved-Jacobsen, Thorkild

2009-04-01

The high pollution load in wastewater at the beginning of a rain event is commonly known to originate from the erosion of sewer sediments due to the increased flow rate under storm weather conditions. It is essential to characterize the biodegradability of organic matter during a storm event in order to quantify the effect it can have further downstream to the receiving water via discharges from Combined Sewer Overflow (CSO). The approach is to characterize the pollutograph during first flush. The pollutograph shows the variation in COD and TSS during a first flush event. These parameters measure the quantity of organic matter present. However these parameters do not indicate detailed information on the biodegradability of the organic matter. Such detailed knowledge can be obtained by dividing the total COD into fractions with different microbial properties. To do so oxygen uptake rate (OUR) measurements on batches of wastewater have shown itself to be a versatile technique. Together with a conceptual understanding of the microbial transformation taking place, OUR measurements lead to the desired fractionation of the COD. OUR results indicated that the highest biodegradability is associated with the initial part of a storm event. The information on physical and biological processes in the sewer can be used to better manage sediment in sewers which can otherwise result in depletion of dissolved oxygen in receiving waters via discharges from CSOs.
Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas with and without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007.

PubMed

Jagai, Jyotsna S; Li, Quanlin; Wang, Shiliang; Messier, Kyle P; Wade, Timothy J; Hilborn, Elizabeth D

2015-09-01

Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff are released into water bodies, potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme precipitation associated with climate change. The aim of this study was to assess whether the association between heavy rainfall and rate of emergency room (ER) visits for gastrointestinal (GI) illness differed in the presence of CSOs. For the study period 2003-2007, time series of daily rate of ER visits for GI illness and meteorological data were organized for three exposure regions: a) CSOs impacting drinking water sources, b) CSOs impacting recreational waters, c) no CSOs. A distributed lag Poisson regression assessed cumulative effects for an 8-day lag period following heavy (≥ 90th and ≥ 95th percentile) and extreme (≥ 99th percentile) precipitation events, controlling for temperature and long-term time trends. The association between extreme rainfall and rate of ER visits for GI illness differed among regions. Only the region with drinking water exposed to CSOs demonstrated a significant increased cumulative risk for rate (CRR) of ER visits for GI for all ages in the 8-day period following extreme rainfall: CRR: 1.13 (95% CI: 1.00, 1.28) compared with no rainfall. The rate of ER visits for GI illness was associated with extreme precipitation in the area with CSO discharges to a drinking water source. Our findings suggest an increased risk for GI illness among consumers whose drinking water source may be impacted by CSOs after extreme precipitation. Jagai JS, Li Q, Wang S, Messier KP, Wade TJ, Hilborn ED. 2015. Extreme precipitation and emergency room visits for gastrointestinal illness in areas with and without combined sewer systems: an analysis of Massachusetts data, 2003-2007. Environ Health Perspect 123:873-879; http://dx.doi.org/10.1289/ehp.1408971.
EPA’s Stormwater Management Model (SWMM)

EPA Pesticide Factsheets

EPA’s Storm Water Management Model (SWMM) is used throughout the world for planning, analysis, and designrelated to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas.
Spatial variability of polycyclic aromatic hydrocarbon load of urban wet weather pollution in combined sewers.

PubMed

Gasperi, J; Moilleron, R; Chebbo, G

2006-01-01

In Paris, the OPUR research programme created an experimental on-site observatory of urban pollutant loads in combined sewer systems in order to characterise the dry and wet weather flows at different spatial scales. This article presents the first results on the spatial variability of the polycyclic aromatic hydrocarbon (PAH) load during wet weather flow (WWF). At the scale of a rain event, investigations revealed that (i) PAH concentrations were relatively homogenous whatever the spatial scale and were greater than those of the dry weather flow (DWF), (ii) PAH distributions between dissolved and particulate phases were constant, and (iii) PAH fingerprints exhibited a similar pattern for all catchments. Moreover, an evaluation of the contribution of DWF, runoff and erosion of sewer deposits to WWF load was established. According to the hypothesis on the runoff concentration, the contributions were evaluated at 14, 8 and 78%, respectively, at the scale of the Marais catchment. For all the catchments, the runoff contribution was found quite constant and evaluated at approximately 10%. The DWF contribution seems to increase with the catchment area, contrary to the sewer erosion contribution, which seems to decrease. However, this latter still remains an important source of pollution. These first trends should be confirmed and completed by more investigations of rain events.
Vapor Intrusion from Entrapped NAPL Sources and Groundwater Plumes: Process Understanding and Improved Modeling Tools for Pathway Assessment

DTIC Science & Technology

2014-07-01

into a building ....149 Figure 5.52: Effect of infiltration at 1 mm/hr for 24 hours on vapor signals in sandy clay loam scenario...shown above, there will also likely be large diameter sanitary sewers running the length of each street. Each house on the street will have a sewer...permeability, a discontinuous clay layer system, and a system with scattered obstacles (e.g. utilities). The layered systems indicated that the sequence of
40 CFR 35.940-2 - Unallowable costs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... approved project; (f) Interest on bonds or any other form of indebtedness required to finance the project... example, sewer rights-of-way, sewage treatment plantsite, sanitary landfills and sludge disposal areas...
Removal of nutrients from combined sewer overflows and lake water in a vertical-flow constructed wetland system.

PubMed

Gervin, L; Brix, H

2001-01-01

Lake Utterslev is situated in a densely built-up area of Copenhagen, and is heavily eutrophicated from combined sewer overflows. At the same time the lake suffers from lack of water. Therefore, a 5,000 m2 vertical flow wetland system was constructed in 1998 to reduce the phosphorus discharge from combined sewer overflows without reducing the water supply to the lake. During dry periods the constructed wetland is used to remove phosphorus from the lake water. The system is designed as a 90 m diameter circular bed with a bed depth of c. 2 m. The system is isolated from the surroundings by a polyethylene membrane. The bed medium consists of a mixture of gravel and crushed marble, which has a high binding capacity for phosphorus. The bed is located within the natural littoral zone of the lake and is planted with common reed (Phragmites australis). The constructed wetland is intermittently loaded with combined sewer overflow water or lake water and, after percolation through the bed medium, the water is collected in a network of drainage pipes at the bottom of the bed and pumped to the lake. The fully automated loading cycle results in alternating wet and dry periods. During the initial two years of operation, the phosphorus removal for combined sewer overflows has been consistently high (94-99% of inflow concentrations). When loaded with lake water, the phosphorus removal has been high during summer (71-97%) and lower during winter (53-75%) partly because of lower inlet concentrations. Effluent phosphorus concentrations are consistently low (0.03-0.04 mg/L). Ammonium nitrogen is nitrified in the constructed wetland, and total suspended solids and COD are generally reduced to concentrations below 5 mg/L and 25 mg/L, respectively. The study documents that a subsurface flow constructed wetland system can be designed and operated to effectively remove phosphorus and other pollutants from combined sewer overflows and eutrophicated lake water.
Contributions of combined sewer overflows and treated effluents to the bacterial load released into a coastal area.

PubMed

Al Aukidy, M; Verlicchi, P

2017-12-31

The impact of combined sewer overflow (CSO) on the receiving water body is an issue of increasing concern, as it may lead to restrictions in the use and destination of the receiving body, such as bathing or recreational area closures, fish and shellfish consumption restrictions, and contamination of drinking water resources. Recent investigations have mainly referred to the occurrence and loads of suspended solids, organic compounds and, in some cases, micropollutants. Attempts have been made to find correlations between the discharged load and the size and characteristics of the catchment area, climate conditions, rainfall duration and intensity. This study refers to a touristic coastal area in the north-east of Italy, which is characterized by a combined sewer network including 5 CSO outfalls which, in the case of heavy rain events, directly discharge the exceeding water flow rate into channels which, after a short distance, reach the Adriatic Sea. The study analyzed: i) rainfall events during the summer period in 2014 which led to overflow in the different outfalls, ii) the inter- and intra-event variability with regard to E. coli, Enterococci and conductivity, and iii) the hydraulic and pollutant (E. coli and Enterococci) loads discharged by the local wastewater treatment plant and by all the CSO outfalls. Finally, it estimated the contribution of each source to the released hydraulic and pollutant loads into the receiving water body. Moreover, it was also found that the modest water volume discharged by all CSO outfalls (only 8% of the total volume discharged by the area) contains >90% of the microbial load. Copyright © 2017 Elsevier B.V. All rights reserved.
USEPA CAPSTONE REPORT: CONTROL AND TREATMENT

EPA Science Inventory

Combined-sewer overflows (CSOs), sanitary-sewer overflows and stormwater (SW) are significant contributors of contamination to surface waters. During a rain event, the flow in a combined sewer system may exceed the capacity of the intercepting sewer leading to the wastewater trea...
FLUSHING FOR SEWER SEDIMENT, CORROSION, AND POLLUTION CONTROL

EPA Science Inventory

This presentation overviews causes of sewer deterioration and heavy pollutant discharges caused by rain events together with a discussion of their control methods. In particular, it covers in-sewer- and combined sewer overflow- (CSO-) storage-tank-flushing systems for removal of ...
Quantifying radar-rainfall uncertainties in urban drainage flow modelling

NASA Astrophysics Data System (ADS)

Rico-Ramirez, M. A.; Liguori, S.; Schellart, A. N. A.

2015-09-01

This work presents the results of the implementation of a probabilistic system to model the uncertainty associated to radar rainfall (RR) estimates and the way this uncertainty propagates through the sewer system of an urban area located in the North of England. The spatial and temporal correlations of the RR errors as well as the error covariance matrix were computed to build a RR error model able to generate RR ensembles that reproduce the uncertainty associated with the measured rainfall. The results showed that the RR ensembles provide important information about the uncertainty in the rainfall measurement that can be propagated in the urban sewer system. The results showed that the measured flow peaks and flow volumes are often bounded within the uncertainty area produced by the RR ensembles. In 55% of the simulated events, the uncertainties in RR measurements can explain the uncertainties observed in the simulated flow volumes. However, there are also some events where the RR uncertainty cannot explain the whole uncertainty observed in the simulated flow volumes indicating that there are additional sources of uncertainty that must be considered such as the uncertainty in the urban drainage model structure, the uncertainty in the urban drainage model calibrated parameters, and the uncertainty in the measured sewer flows.
SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) TOOLBOX

EPA Science Inventory

Description: The Nation's sanitary-sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 SSO events per year. Becau...
EPA SSOAP Toolbox – Evolution and Applications

EPA Science Inventory

The nation’s sanitary sewer infrastructure is aging, with some sewers dating back more than 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) ...
Measuring Flow Reductions in a Combined Sewer System using Green Infrastructure - abstract

EPA Science Inventory

In 2009, the Louisville and Jefferson County Metropolitan Sewer District (MSD) submitted an Integrated Overflow Abatement Plan (IOAP) addressing combined sewer overflows (CSOs) and sanitary sewer overflows. Many of the solutions involve gray infrastructure, such as large, end-of...
SEWER SEDIMENT AND CONTROL: A MANAGEMENT PRACTICES REFERENCES GUIDE

EPA Science Inventory

Sewer-solids sediment is one of major sources of pollutants in urban wet-weather flow (WWF) discharges that include combined-sewer overflow (CSO), separate sanitary-sewer overflow (SSO), and stormwater runoff. During low-flow, dry-weather periods, sanitary wastewater solids depo...
FLUSHING FOR SEWER SEDIMENT, CORROSION, AND POLLUTION CONTROL

EPA Science Inventory

This paper overviews causes of combined-sewer deterioration and their heavy pollutant discharges caused by rain events together with a discussion of their control methods. In particular, it covers in-sewer and combined-sewer overflow (CSO) storage-tank-flushing systems for removi...
PLANNING FOR SSO CONTROL: HENRICO COUNTY, VA - CASE STUDY

EPA Science Inventory

The Nation's sanitary-sewer infrastructure is aging with some sewers dating back over 100 years. There are more than 19,500 municipal sanitary-sewer collection systems nationwide serving an estimated 150M people and comprising about 500,000 sewer miles. It is estimated that there...
COMPUTER MODEL ANALYSIS FOR CONTROL PLANNING OF SANITARY-SEWER OVERFLOWS

EPA Science Inventory

The Nation's sanitary-sewer infrastructure is aging with some sewers dating back over 100 years. There are more than 19,500 municipal sanitary-sewer collection systems nationwide serving an estimated 150 million people and comprising about 800,000 km (500,000 mi) of municipally ...
HANDBOOK: SEWER SYSTEM INFRASTRUCTURE ANALYSIS AND REHABILITATION

EPA Science Inventory

Many of our Nation's sewer systems date back to the 19th Century when brick sewers were common. hese and more recent sewer systems can be expected to fail in time, but because they are placed underground, signs of accelerated deterioration and capacity limitations are not readily...
Occurrence of organic wastewater-indicator compounds in urban streams of the Atlanta area, Georgia, 2003-2006

USGS Publications Warehouse

Lawrence, Stephen J.; LaFontaine, Jacob H.

2010-01-01

The similarity in the pattern and distribution of OWICs in samples at sites upstream and downstream from known CSO outfalls indicates that CSOs were not the dominant source of OWICs during the study period. Other sources may include non-sewage discharges-both permitted, permitted but out of compliance, and non-permitted, contaminated groundwater from leaking sewer lines or septic systems, sanitary-sewer overflows, or dry-weather runoff from outdoor water use. These OWICs may be better suited for identifying sewage-contaminated groundwater than sewage-contaminated surface water because groundwater is not typically affected by the OWICs that are more common in urban runoff.

EPA SSOAP Toolbox Application for Condition and Capacity Assessment of Wastewater Collection Systems - Paper

EPA Science Inventory

The nation’s sanitary sewer infrastructure is aging, with some sewers dating back more than 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events ...
EPA SSOAP Toolbox Application for Condition and Capacity Assessment of Wastewater Collection Systems

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events per ...
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

EPA Science Inventory

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampl...
Preface: Workshop on Off-Grid Technology Systems

NASA Astrophysics Data System (ADS)

Alonso-Marroquin, Fernando

2017-06-01

Off-grid houses are dwellings that do not rely on water supply, sewer, or electrical power grid, and are able to operate independently of all public utility services. These houses are ideal for remote communities or population suffering natural or human-made disasters. Our aim is to develop compact and affordable off-grid technologies by integrating high-end nano-engineering with systems that imitates natural biological processes. The key areas of focus in the workshop were: solar energy harvesting using nanotechnology, wind energy harvesting from vertical-axis wind turbines, supercapacitors energy storage systems, treatment of greywater, and green roofs to achieve air comfort.
Remaining Sites Verification Package for the 100-F-26:12, 1.8-m (72-in.) Main Process Sewer Pipeline, Waste Site Reclassification Form 2007-034

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. M. Capron

2008-04-29

The 100-F-26:12 waste site was an approximately 308-m-long, 1.8-m-diameter east-west-trending reinforced concrete pipe that joined the North Process Sewer Pipelines (100-F-26:1) and the South Process Pipelines (100-F-26:4) with the 1.8-m reactor cooling water effluent pipeline (100-F-19). In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Influence of high resolution rainfall data on the hydrological response of urban flat catchments

NASA Astrophysics Data System (ADS)

Cristiano, Elena; ten Veldhuis, Marie-claire; van de Giesen, Nick

2016-04-01

In the last decades, cities have become more and more urbanized and population density in urban areas is increased. At the same time, due to the climate changes, rainfall events present higher intensity and shorter duration than in the past. The increase of imperviousness degree, due to urbanization, combined with short and intense rainfall events, determinates a fast hydrological response of the urban catchment and in some cases it can lead to flooding. Urban runoff processes are sensitive to rainfall spatial and temporal variability and, for this reason, high resolution rainfall data are required as input for the hydrological model. A better knowledge of the hydrological response of system can help to prevent damages caused by flooding. This study aims to evaluate the sensitivity of urban hydrological response to spatial and temporal rainfall variability in urban areas, focusing especially on understanding the hydrological behaviour in lowland areas. In flat systems, during intense rainfall events, the flow in the sewer network can be pressurized and it can change direction, depending on the setting of pumping stations and CSOs (combined sewer overflow). In many cases these systems are also looped and it means that the water can follow different paths, depending on the pipe filling process. For these reasons, hydrological response of flat and looped catchments is particularly complex and it can be difficult characterize and predict it. A new dual polarimetric X-band weather radar, able to measure rainfall with temporal resolution of 1 min and spatial resolution of 100mX100m, was recently installed in the city of Rotterdam (NL). With this instrument, high resolution rainfall data were measured and used, in this work, as input for the hydrodynamic model. High detailed, semi-distributed hydrodynamic models of some districts of Rotterdam were used to investigate the hydrological response of flat catchments to high resolution rainfall data. In particular, the hydrological response of some subcatchments of the district of Kralingen was studied. Rainfall data were combined with level and discharge measurements at the pumping station that connects the sewer system with the waste water treatment plane. Using this data it was possible to study the water balance and to have a better idea of the amount of water that leave the system during a specific rainfall events. Results show that the hydrological response of flat and looped catchments is sensitive to spatial and temporal rainfall variability and it can be strongly influenced by rainfall event characteristics, such as intensity, velocity and intermittency of the storm.
Sewage Monitors

NASA Technical Reports Server (NTRS)

1987-01-01

Every U.S. municipality must determine how much waste water it is processing and more importantly, how much is going unprocessed into lakes and streams either because of leaks in the sewer system or because the city's sewage facilities were getting more sewer flow than they were designed to handle. ADS Environmental Services, Inc.'s development of the Quadrascan Flow Monitoring System met the need for an accurate method of data collection. The system consists of a series of monitoring sensors and microcomputers that continually measure water depth at particular sewer locations and report their findings to a central computer. This provides precise information to city managers on overall flow, flow in any section of the city, location and severity of leaks and warnings of potential overload. The core technology has been expanded upon in terms of both technical improvements, and functionality for new applications, including event alarming and control for critical collection system management problems.
Fractal analysis of urban catchments and their representation in semi-distributed models: imperviousness and sewer system

NASA Astrophysics Data System (ADS)

Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel; Ochoa-Rodriguez, Susana; Willems, Patrick; Ichiba, Abdellah; Wang, Lipen; Pina, Rui; Van Assel, Johan; Bruni, Guendalina; Murla Tuyls, Damian; ten Veldhuis, Marie-Claire

2017-04-01

Land use distribution and sewer system geometry exhibit complex scale dependent patterns in urban environment. This scale dependency is even more visible in a rasterized representation where only a unique class is affected to each pixel. Such features are well grasped with fractal tools, which are based scale invariance and intrinsically designed to characterise and quantify the space filled by a geometrical set exhibiting complex and tortuous patterns. Fractal tools have been widely used in hydrology but seldom in the specific context of urban hydrology. In this paper, they are used to analyse surface and sewer data from 10 urban or peri-urban catchments located in 5 European countries in the framework of the NWE Interreg RainGain project (www.raingain.eu). The aim was to characterise urban catchment properties accounting for the complexity and inhomogeneity typical of urban water systems. Sewer system density and imperviousness (roads or buildings), represented in rasterized maps of 2 m x 2 m pixels, were analysed to quantify their fractal dimension, characteristic of scaling invariance. It appears that both sewer density and imperviousness exhibit scale invariant features that can be characterized with the help of fractal dimensions ranging from 1.6 to 2, depending on the catchment. In a given area, consistent results were found for the two geometrical features, yielding a robust and innovative way of quantifying the level of urbanization. The representation of imperviousness in operational semi-distributed hydrological models for these catchments was also investigated by computing fractal dimensions of the geometrical sets made up of the sub-catchments with coefficients of imperviousness greater than a range of thresholds. It enables to quantify how well spatial structures of imperviousness are represented in the urban hydrological models.
Contribution of directly connected and isolated impervious areas to urban drainage network hydrographs

NASA Astrophysics Data System (ADS)

Seo, Y.; Choi, N.-J.; Schmidt, A. R.

2013-05-01

This paper addresses the mass balance error observed in runoff hydrographs in urban watersheds by introducing assumptions regarding the contribution of infiltrated rainfall from pervious areas and isolated impervious area (IIA) to the runoff hydrograph. Rainfall infiltrating into pervious areas has been assumed not to contribute to the runoff hydrograph until Hortonian excess rainfall occurs. However, mass balance analysis in an urban watershed indicates that rainfall infiltrated to pervious areas can contribute to direct runoff hydrograph, thereby offering an explanation for the long hydrograph tail commonly observed in runoff from urban storm sewers. In this study, a hydrologic analysis based on the width function is introduced, with two types of width functions obtained from both pervious and impervious areas, respectively. The width function can be regarded as the direct interpretation of the network response. These two width functions are derived to obtain distinct response functions for directly connected impervious areas (DCIA), IIA, and pervious areas. The results show significant improvement in the estimation of runoff hydrographs and suggest the need to consider the flow contribution from pervious areas to the runoff hydrograph. It also implies that additional contribution from flow paths through joints and cracks in sewer pipes needs to be taken into account to improve the estimation of runoff hydrographs in urban catchments.
Contribution of directly connected and isolated impervious areas to urban drainage network hydrographs

NASA Astrophysics Data System (ADS)

Seo, Y.; Choi, N.-J.; Schmidt, A. R.

2013-09-01

This paper addresses the mass balance error observed in runoff hydrographs in urban watersheds by introducing assumptions regarding the contribution of infiltrated rainfall from pervious areas and isolated impervious area (IIA) to the runoff hydrograph. Rainfall infiltrating into pervious areas has been assumed not to contribute to the runoff hydrograph until Hortonian excess rainfall occurs. However, mass balance analysis in an urban watershed indicates that rainfall infiltrated to pervious areas can contribute directly to the runoff hydrograph, thereby offering an explanation for the long hydrograph tail commonly observed in runoff from urban storm sewers. In this study, a hydrologic analysis based on the width function is introduced, with two types of width functions obtained from both pervious and impervious areas, respectively. The width function can be regarded as the direct interpretation of the network response. These two width functions are derived to obtain distinct response functions for directly connected impervious areas (DCIA), IIA, and pervious areas. The results show significant improvement in the estimation of runoff hydrographs and suggest the need to consider the flow contribution from pervious areas to the runoff hydrograph. It also implies that additional contribution from flow paths through joints and cracks in sewer pipes needs to be taken into account to improve the estimation of runoff hydrographs in urban catchments.
A framework for probabilistic pluvial flood nowcasting for urban areas

NASA Astrophysics Data System (ADS)

Ntegeka, Victor; Murla, Damian; Wang, Lipen; Foresti, Loris; Reyniers, Maarten; Delobbe, Laurent; Van Herk, Kristine; Van Ootegem, Luc; Willems, Patrick

2016-04-01

Pluvial flood nowcasting is gaining ground not least because of the advancements in rainfall forecasting schemes. Short-term forecasts and applications have benefited from the availability of such forecasts with high resolution in space (~1km) and time (~5min). In this regard, it is vital to evaluate the potential of nowcasting products for urban inundation applications. One of the most advanced Quantitative Precipitation Forecasting (QPF) techniques is the Short-Term Ensemble Prediction System, which was originally co-developed by the UK Met Office and Australian Bureau of Meteorology. The scheme was further tuned to better estimate extreme and moderate events for the Belgian area (STEPS-BE). Against this backdrop, a probabilistic framework has been developed that consists of: (1) rainfall nowcasts; (2) sewer hydraulic model; (3) flood damage estimation; and (4) urban inundation risk mapping. STEPS-BE forecasts are provided at high resolution (1km/5min) with 20 ensemble members with a lead time of up to 2 hours using a 4 C-band radar composite as input. Forecasts' verification was performed over the cities of Leuven and Ghent and biases were found to be small. The hydraulic model consists of the 1D sewer network and an innovative 'nested' 2D surface model to model 2D urban surface inundations at high resolution. The surface components are categorized into three groups and each group is modelled using triangular meshes at different resolutions; these include streets (3.75 - 15 m2), high flood hazard areas (12.5 - 50 m2) and low flood hazard areas (75 - 300 m2). Functions describing urban flood damage and social consequences were empirically derived based on questionnaires to people in the region that were recently affected by sewer floods. Probabilistic urban flood risk maps were prepared based on spatial interpolation techniques of flood inundation. The method has been implemented and tested for the villages Oostakker and Sint-Amandsberg, which are part of the larger city of Gent, Belgium. After each of the different above-mentioned components were evaluated, they were combined and tested for recent historical flood events. The rainfall nowcasting, hydraulic sewer and 2D inundation modelling and socio-economical flood risk results each could be partly evaluated: the rainfall nowcasting results based on radar data and rain gauges; the hydraulic sewer model results based on water level and discharge data at pumping stations; the 2D inundation modelling results based on limited data on some recent flood locations and inundation depths; the results for the socio-economical flood consequences of the most extreme events based on claims in the database of the national disaster agency. Different methods for visualization of the probabilistic inundation results are proposed and tested.
Investigation of Pharmaceutical Residues in Hospital Effluents, in Ground- and Drinking Water from Bundeswehr Facilities, and their Removal During Drinking Water Purification (Arzneimittelrueckstaende in Trinkwasser(versorgungsanlagen) und Krankenhausabwaessern der Bundeswehr: Methodenentwicklung - Verkommen - Wasseraufbereitung)

DTIC Science & Technology

1999-11-01

Drinking water processing plant , Analysis, Calculation model, Field experiment 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION...sewage effluents and from the sewer of the municipal sewage treatment plant in Berlin-Ruhleben. In the field trials, the MDWPUs that both apply reverse...waste water samples, along the municipal sewer system and In the influents and effluents of the receiving sewage treatment plants . To estimate the
Constructing and dismantling frameworks of disease etiology: the rise and fall of sewer gas in America, 1870-1910.

PubMed Central

An, Perry G.

2004-01-01

For roughly forty years, from 1870 to 1910, Americans recognized and feared gases emanating from sewers, believing that they were responsible for causing an array of diseases. Fears of sewer gas arose from deeper anxieties toward contact with decomposing organic matter and the vapors emitted from such refuse. These anxieties were exacerbated by the construction of sewers across the country during the mid-to-late-nineteenth century, which concentrated waste emanations and connected homes to one another. The result was the birth of sewer gas and the attribution of sickness and death to it, as well as the development of a host of plumbing devices and, especially, bathroom fixtures, to combat sewer gas. The rise of the germ theory, laboratory science, and belief in disease specificity, however, transformed the threat of sewer gas, eventually replacing it (and the larger fear of miasmas) with the threat of germs. The germ theory framework, by 1910, proved more suitable than the sewer gas framework in explaining disease causation; it is this suitability that often shapes the relationship between science and society. PMID:15829149
Development and implementation of a real-time control strategy for the sewer system of the city of Vienna.

PubMed

Fuchs, L; Beeneken, T

2005-01-01

The paper describes the realization of a real-time control for the Vienna sewer system. The project is scheduled for completion for 2004. The 3.5 year project comprises all planning stages starting with the recording of data up to the planning of measuring and controlling units. The concrete steps of the planning stages are explained. A measuring system including 25 rainfall measurements, 40 flow measurements and 20 water level measurements is implemented as an online system. This measuring system is designed to achieve two objectives, on the one hand the real-time control and on the other hand the calibration of the model that is used for the hydrodynamic sewer system simulation. The approx. 53,000 pipes have served to generate a coarse network of no more than approx. 2600 pipes. The area data were derived with high accuracy from available aerial photograph interpretations. With simulation runs of a rule-based control software the system operation was examined. A self-learning system will improve the rule basis. A forecasting model that uses weather observation radar will additionally influence the controlling decisions. The findings from the investigations are immediately considered in the planning of measuring and control units. The simulated results for the first phase of implementation, which demonstrate the benefit of RTC for the Vienna sewer system, are explained.
Biological assessment and streambed-sediment chemistry of streams in the Indianapolis metropolitan area, Indiana, 2003–2008

USGS Publications Warehouse

Voelker, David C.

2012-01-01

During 2003–2008, the U.S. Geological Survey sampled 13 sites in the Indianapolis metropolitan area in Indiana for benthic invertebrates, fish communities, and streambed-sediment chemistry. Data from seven White River sites and six tributary sites complement surface-water chemistry data collected by the Indianapolis Department of Public Works. The information is being used to assess changes in water quality in conjunction with the City's programs to reduce combined sewer overflows and other point and nonpoint sources of pollution in the Indianapolis area. During the study, 233 benthic-invertebrate taxa were identified from which the Ephemeroptera, Plecoptera, and Trichoptera (EPT) Index, the Hilsenhoff Biotic Index (HBI), and the Invertebrate Community Index (ICI) were calculated. EPT index scores ranged from 2 to 16 on the White River and from 2 to 17 on the tributaries. EPT index scores indicate that these pollution-intolerant taxa are more prevalent upstream from and away from the combined-sewer areas of Indianapolis. HBI scores from sites on the White River ranged from 4.67 (good) to 9.55 (very poor), whereas on the tributaries, scores ranged from 4.21 (very good) to 8.14 (poor). Lower HBI scores suggest that less organic pollution was present and, like the EPT scores, indicate better conditions where combined-sewer overflows (CSOs) are not present. Similarly, ICI scores indicated better conditions upstream from the CSO outfalls on the White River. White River scores ranged from 12 to 46, where higher ICI scores indicate better conditions in the benthic-invertebrate community. ICI scores at the tributary sites ranged from 12 to 52, with the highest scores on streams without CSOs.
Mortality rates of pathogen indicator microorganisms discharged from point and non-point sources in an urban area.

PubMed

Kim, Geonha; Hur, Jin

2010-01-01

This research measured the mortality rates of pathogen indicator microorganisms discharged from various point and non-point sources in an urban area. Water samples were collected from a domestic sewer, a combined sewer overflow, the effluent of a wastewater treatment plant, and an urban river. Mortality rates of indicator microorganisms in sediment of an urban river were also measured. Mortality rates of indicator microorganisms in domestic sewage, estimated by assuming first order kinetics at 20 degrees C were 0.197 day(-1), 0.234 day(-1), 0.258 day(-1) and 0.276 day(-1) for total coliform, fecal coliform, Escherichia coli, and fecal streptococci, respectively. Effects of temperature, sunlight irradiation and settlement on the mortality rate were measured. Results of this research can be used as input data for water quality modeling or can be used as design factors for treatment facilities.
75 FR 53342 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-31

... including raw sewage from the City's sanitary sewer system and its separate storm sewer system, as well as a... remedial measures, including necessary upgrades to its sanitary sewer system and separate storm sewer system, over a period of approximately twelve years and at an estimated cost of approximately $50 million...
Adaptive management of urban watersheds

NASA Astrophysics Data System (ADS)

Garmestani, A.; Shuster, W.; Green, O. O.

2013-12-01

Consent decree settlements for violations of the Clean Water Act (1972) increasingly include provisions for redress of combined sewer overflow activity through hybrid approaches that incorporate the best of both gray (e.g., storage tunnels) and green infrastructure (e.g., rain gardens). Adaptive management is an environmental management strategy that uses an iterative process of decision-making to improve environmental management via system monitoring. A central tenet of adaptive management is that management involves a learning process that can help regulated communities achieve environmental quality objectives. We are using an adaptive management approach to guide a green infrastructure retrofit of a neighborhood in the Slavic Village Development Corporation area (Cleveland, Ohio). We are in the process of gathering hydrologic and ecosystem services data and will use this data as a basis for collaboration with area citizens on a plan to use green infrastructure to contain stormflows. Monitoring data provides researchers with feedback on the impact of green infrastructure implementation and suggest where improvements can be made.
Sulfide and methane production in sewer sediments.

PubMed

Liu, Yiwen; Ni, Bing-Jie; Ganigué, Ramon; Werner, Ursula; Sharma, Keshab R; Yuan, Zhiguo

2015-03-01

Recent studies have demonstrated significant sulfide and methane production by sewer biofilms, particularly in rising mains. Sewer sediments in gravity sewers are also biologically active; however, their contribution to biological transformations in sewers is poorly understood at present. In this study, sediments collected from a gravity sewer were cultivated in a laboratory reactor fed with real wastewater for more than one year to obtain intact sediments. Batch test results show significant sulfide production with an average rate of 9.20 ± 0.39 g S/m(2)·d from the sediments, which is significantly higher than the areal rate of sewer biofilms. In contrast, the average methane production rate is 1.56 ± 0.14 g CH4/m(2)·d at 20 °C, which is comparable to the areal rate of sewer biofilms. These results clearly show that the contributions of sewer sediments to sulfide and methane production cannot be ignored when evaluating sewer emissions. Microsensor and pore water measurements of sulfide, sulfate and methane in the sediments, microbial profiling along the depth of the sediments and mathematical modelling reveal that sulfide production takes place near the sediment surface due to the limited penetration of sulfate. In comparison, methane production occurs in a much deeper zone below the surface likely due to the better penetration of soluble organic carbon. Modelling results illustrate the dependency of sulfide and methane productions on the bulk sulfate and soluble organic carbon concentrations can be well described with half-order kinetics. Copyright © 2014 Elsevier Ltd. All rights reserved.
Tree root intrusion in sewer systems: A review of extent and costs

Treesearch

T.B. Randrup; E.G. McPherson; L.R. Costello

2001-01-01

Interference between trees and sewer systems is likely to occur in old systems and in cracked pipes. Factors that contribute to damage include old pipes with joints, shallow pipes, small-dimension pipes, and fast-growing tree species. Because roots are reported to cause >50% of all sewer blockages, costs associated with root removal from sewers is substantial. In...

Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas with and without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003–2007

PubMed Central

Li, Quanlin; Wang, Shiliang; Messier, Kyle P.; Wade, Timothy J.; Hilborn, Elizabeth D.

2015-01-01

Background Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff are released into water bodies, potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme precipitation associated with climate change. Objectives The aim of this study was to assess whether the association between heavy rainfall and rate of emergency room (ER) visits for gastrointestinal (GI) illness differed in the presence of CSOs. Methods For the study period 2003–2007, time series of daily rate of ER visits for GI illness and meteorological data were organized for three exposure regions: a) CSOs impacting drinking water sources, b) CSOs impacting recreational waters, c) no CSOs. A distributed lag Poisson regression assessed cumulative effects for an 8-day lag period following heavy (≥ 90th and ≥ 95th percentile) and extreme (≥ 99th percentile) precipitation events, controlling for temperature and long-term time trends. Results The association between extreme rainfall and rate of ER visits for GI illness differed among regions. Only the region with drinking water exposed to CSOs demonstrated a significant increased cumulative risk for rate (CRR) of ER visits for GI for all ages in the 8-day period following extreme rainfall: CRR: 1.13 (95% CI: 1.00, 1.28) compared with no rainfall. Conclusions The rate of ER visits for GI illness was associated with extreme precipitation in the area with CSO discharges to a drinking water source. Our findings suggest an increased risk for GI illness among consumers whose drinking water source may be impacted by CSOs after extreme precipitation. Citation Jagai JS, Li Q, Wang S, Messier KP, Wade TJ, Hilborn ED. 2015. Extreme precipitation and emergency room visits for gastrointestinal illness in areas with and without combined sewer systems: an analysis of Massachusetts data, 2003–2007. Environ Health Perspect 123:873–879; http://dx.doi.org/10.1289/ehp.1408971 PMID:25855939
The characteristics of dissolved organic matter (DOM) in storm sewer sediments and the binding interaction with Cu(II) in four typical regions in Beijing, China.

PubMed

Zhang, Ziyang; Li, Kun; Zhang, Xiaoran; Li, Haiyan

2017-07-01

In this work, dissolved organic matter (DOM) was extracted from storm sewer sediments collected in four typical regions (residential, campus, traffic and business regions) in Beijing, China. The basic characteristics of DOM were analyzed by UV-visible spectroscopy (UV-Vis), excitation-emission matrix Fluorescence Spectroscopy and Fourier Transform Infrared Spectroscopy. Furthermore, the complexation between DOM and Cu(II) were investigated. The results showed that there were large amount of aromatic structure in the DOM extracted from storm sewer sediments. The microbial activities had also made a contribution to the DOM in storm sewer sediments. The composition of DOM influenced the complexing capacity of Cu(II) greatly, which may be attributed to the protein-like and humic-like substances in storm sewer sediments. This study demonstrated valuable information on the structure present in the DOM of storm sewer sediments and provided new insight for exploring the relationship between DOM and co-existing heavy metals in storm sewer sediments.
Degradability of creatinine under sewer conditions affects its potential to be used as biomarker in sewage epidemiology.

PubMed

Thai, Phong K; O'Brien, Jake; Jiang, Guangming; Gernjak, Wolfgang; Yuan, Zhiguo; Eaglesham, Geoff; Mueller, Jochen F

2014-05-15

Creatinine was proposed to be used as a population normalising factor in sewage epidemiology but its stability in the sewer system has not been assessed. This study thus aimed to evaluate the fate of creatinine under different sewer conditions using laboratory sewer reactors. The results showed that while creatinine was stable in wastewater only, it degraded quickly in reactors with the presence of sewer biofilms. The degradation followed first order kinetics with significantly higher rate in rising main condition than in gravity sewer condition. Additionally, daily loads of creatinine were determined in wastewater samples collected on Census day from 10 wastewater treatment plants around Australia. The measured loads of creatinine from those samples were much lower than expected and did not correlate with the populations across the sampled treatment plants. The results suggested that creatinine may not be a suitable biomarker for population normalisation purpose in sewage epidemiology, especially in sewer catchment with high percentage of rising mains. Copyright © 2014 Elsevier Ltd. All rights reserved.
Quantification of sewer system infiltration using delta(18)O hydrograph separation.

PubMed

Prigiobbe, V; Giulianelli, M

2009-01-01

The infiltration of parasitical water into two sewer systems in Rome (Italy) was quantified during a dry weather period. Infiltration was estimated using the hydrograph separation method with two water components and delta(18)O as a conservative tracer. The two water components were groundwater, the possible source of parasitical water within the sewer, and drinking water discharged into the sewer system. This method was applied at an urban catchment scale in order to test the effective water-tightness of two different sewer networks. The sampling strategy was based on an uncertainty analysis and the errors have been propagated using Monte Carlo random sampling. Our field applications showed that the method can be applied easily and quickly, but the error in the estimated infiltration rate can be up to 20%. The estimated infiltration into the recent sewer in Torraccia is 14% and can be considered negligible given the precision of the method, while the old sewer in Infernetto has an estimated infiltration of 50%.
Identifying the best locations to install flow control devices in sewer networks to enable in-sewer storage

NASA Astrophysics Data System (ADS)

Leitão, J. P.; Carbajal, J. P.; Rieckermann, J.; Simões, N. E.; Sá Marques, A.; de Sousa, L. M.

2018-01-01

The activation of available in-sewer storage volume has been suggested as a low-cost flood and combined sewer overflow mitigation measure. However, it is currently unknown what the attributes for suitable objective functions to identify the best location for flow control devices are and the impact of those attributes on the results. In this study, we present a novel location model and efficient algorithm to identify the best location(s) to install flow limiters. The model is a screening tool that does not require hydraulic simulations but rather considers steady state instead of simplistic static flow conditions. It also maximises in-sewer storage according to different reward functions that also considers the potential impact of flow control device failure. We demonstrate its usefulness on two real sewer networks, for which an in-sewer storage potential of approximately 2,000 m3 and 500 m3 was estimated with five flow control devices installed.
Advanced Topics in Wet-Weather Discharge Control

EPA Science Inventory

This report discusses four related but generally independent wet-weather flow (WWF) topic areas, namely: i) opportunities for advanced practices in WWF control technology, particularly as it applies to sewered systems; ii) tradeoffs between storage facilities (tanks) and enlarged...
Potentials of real time control, stormwater infiltration and urine separation to minimize river impacts: dynamic long term simulation of sewer network, pumping stations, pressure pipes and waste water treatment plant.

PubMed

Peters, C; Keller, S; Sieker, H; Jekel, M

2007-01-01

River Panke (Berlin, Germany) suffers from hydraulic peak loads and pollutant loads from separate sewers and combined sewer overflows (CSOs). Pumping the wastewater through long pressure pipes causes extreme peak loads to the wastewater treatment plant (WWTP) during stormwater events. In order to find a good solution, it is essential not to decide on one approach at the beginning, but to evaluate a number of different approaches. For this reason, an integrated simulation study is carried out, assessing the potentials of real time control (RTC), stormwater infiltration, storage and urine separation. Criteria for the assessment are derived and multi-criteria analysis is applied. Despite spatial limitations, infiltration has the highest potential and is very effective with respect to both overflows and the WWTP. Due to a high percentage of separate systems, urine separation has a similar potential and causes the strongest benefits at the WWTP. Unconventional control strategies can lead to significant improvement (comparable to infiltrating the water from approximately 10% of the sealed area).
Sewer System Management Plan.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Robert C.

A Sewer System Management Plan (SSMP) is required by the State Water Resources Control Board (SWRCB) Order No. 2006-0003-DWQ Statewide General Waste Discharge Requirements (WDR) for Sanitary Sewer Systems (General Permit). DOE, National Nuclear Security Administration (NNSA), Sandia Field Office has filed a Notice of Intent to be covered under this General Permit. The General Permit requires a proactive approach to reduce the number and frequency of sanitary sewer overflows (SSOs) within the State. SSMPs must include provisions to provide proper and efficient management, operation, and maintenance of sanitary sewer systems and must contain a spill response plan.
[Research on pollution load of sediments in storm sewer in Beijing district].

PubMed

Li, Hai-Yan; Xu, Bo-Ping; Xu, Shang-Ling; Cui, Shuang

2013-03-01

Based on the investigation of sewer sediments in Xi Cheng district in Beijing, scour-release pollution load in one rainfall from sewer sediments was studied by monitoring the pollutants in the run-off of manhole's section. It was shown that the contribution of scour-release pollutants from sewer sediments to sewer outflow was obvious. The contribution rate of the sediments pollution load to runoff outflow in the 84 m pipeline in one rainfall (9 Jul., 2010) was as follows: TN 8.5%, TP 8.2%, COD 18.3%, SS 7.7%, respectively. And the pollutant contribution rate in the 295 m pipeline in another rainfall (4 Aug., 2010) was TN 23.12%, TP 60.01%, COD 33.78%, SS 31.89%. Therefore, it is important to control the pollution from sewer sediments for the improvement of water environment.
Dopant-assisted negative photoionization Ion mobility spectrometry coupled with on-line cooling inlet for real-time monitoring H2S concentration in sewer gas.

PubMed

Peng, Liying; Jiang, Dandan; Wang, Zhenxin; Hua, Lei; Li, Haiyang

2016-06-01

Malodorous hydrogen sulfide (H2S) gas often exists in the sewer system and associates with the problems of releasing the dangerous odor to the atmosphere and causing sewer pipe to be corroded. A simple method is in demand for real-time measuring H2S level in the sewer gas. In this paper, an innovated method based on dopant-assisted negative photoionization ion mobility spectrometry (DANP-IMS) with on-line semiconductor cooling inlet was put forward and successfully applied for the real-time measurement of H2S in sewer gas. The influence of moisture was effectively reduced via an on-line cooling method and a non-equilibrium dilution with drift gas. The limits of quantitation for the H2S in ≥60% relative humidity air could be obtained at ≤79.0ng L(-1) with linear ranges of 129-2064ng L(-1). The H2S concentration in a sewer manhole was successfully determined while its product ions were identified by an ion-mobility time-of-fight mass spectrometry. Finally, the correlation between sewer H2S concentration and the daily routines and habits of residents was investigated through hourly or real-time monitoring the variation of sewer H2S in manholes, indicating the power of this DANP-IMS method in assessing the H2S concentration in sewer system. Copyright © 2016 Elsevier B.V. All rights reserved.
VARIATION OF PATHOGEN DENSITIES IN URBAN STORMWATER RUNOFF WITH LAND USE

EPA Science Inventory

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three land use areas (high-density residential, low-density residential, and landscaped commercial). The concentrations of organisms in ...
VARIATION OF PATHOGEN DENSITITES IN URBAN STORMWATER RUNOFF WITH LAND USE

EPA Science Inventory

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three land use areas (high-density residential, low-density residential, and landscaped commercial). The concentrations of organisms in ...
Nowcasting of rainfall and of combined sewage flow in urban drainage systems.

PubMed

Achleitner, Stefan; Fach, Stefan; Einfalt, Thomas; Rauch, Wolfgang

2009-01-01

Nowcasting of rainfall may be used additionally to online rain measurements to optimize the operation of urban drainage systems. Uncertainties quoted for the rain volume are in the range of 5% to 10% mean square error (MSE), where for rain intensities 45% to 75% MSE are noted. For larger forecast periods up to 3 hours, the uncertainties will increase up to some hundred percents. Combined with the growing number of real time control concepts in sewer systems, rainfall forecast is used more and more in urban drainage systems. Therefore it is of interest how the uncertainties influence the final evaluation of a defined objective function. Uncertainty levels associated with the forecast itself are not necessarily transferable to resulting uncertainties in the catchment's flow dynamics. The aim of this paper is to analyse forecasts of rainfall and specific sewer output variables. For this study the combined sewer system of the city of Linz in the northern part of Austria located on the Danube has been selected. The city itself represents a total area of 96 km2 with 39 municipalities connected. It was found that the available weather radar data leads to large deviations in the forecast for precipitation at forecast horizons larger than 90 minutes. The same is true for sewer variables such a CSO overflow for small sub-catchments. Although the results improve for larger spatial scales, acceptable levels at forecast horizons larger than 90 minutes are not reached.
Microbiologically induced deterioration of concrete - A Review

PubMed Central

Wei, Shiping; Jiang, Zhenglong; Liu, Hao; Zhou, Dongsheng; Sanchez-Silva, Mauricio

2013-01-01

Microbiologically induced deterioration (MID) causes corrosion of concrete by producing acids (including organic and inorganic acids) that degrade concrete components and thus compromise the integrity of sewer pipelines and other structures, creating significant problems worldwide. Understanding of the fundamental corrosion process and the causal agents will help us develop an appropriate strategy to minimize the costs in repairs. This review presents how microorganisms induce the deterioration of concrete, including the organisms involved and their colonization and succession on concrete, the microbial deterioration mechanism, the approaches of studying MID and safeguards against concrete biodeterioration. In addition, the uninvestigated research area of MID is also proposed. PMID:24688488
Quantification of groundwater infiltration and surface water inflows in urban sewer networks based on a multiple model approach.

PubMed

Karpf, Christian; Krebs, Peter

2011-05-01

The management of sewer systems requires information about discharge and variability of typical wastewater sources in urban catchments. Especially the infiltration of groundwater and the inflow of surface water (I/I) are important for making decisions about the rehabilitation and operation of sewer networks. This paper presents a methodology to identify I/I and estimate its quantity. For each flow fraction in sewer networks, an individual model approach is formulated whose parameters are optimised by the method of least squares. This method was applied to estimate the contributions to the wastewater flow in the sewer system of the City of Dresden (Germany), where data availability is good. Absolute flows of I/I and their temporal variations are estimated. Further information on the characteristics of infiltration is gained by clustering and grouping sewer pipes according to the attributes construction year and groundwater influence and relating these resulting classes to infiltration behaviour. Further, it is shown that condition classes based on CCTV-data can be used to estimate the infiltration potential of sewer pipes. Copyright © 2011 Elsevier Ltd. All rights reserved.
Ground-water-recharge rates in Nassau and Suffolk counties, New York

USGS Publications Warehouse

Peterson, D.S.

1987-01-01

Groundwater is the sole source of freshwater in Nassau and Suffolk Counties on Long Island; therefore, the rate at which precipitation replenishes the groundwater system may affect future water supplies in some areas. Annual precipitation on Long Island averages 45 inches per year, but less than 23 inches , or 50%, recharges the ground-water system. (Recharge is precipitation that percolates to the ground-water system naturally; it does not include water from stormwater basins or injection wells.) The rate of recharge varies locally and ranges from 29% to 57% of precipitation, depending on land use, season, and amount of storm sewering in the area. Recharge was calculated by subtracting evapotranspiration and direct runoff values from known precipitation values. Evapotranspiration was calculated by the Thornwaite and Mather method, and direct runoff rates to streams were calculated from streamflow records and size of known storm-sewer service areas. This report includes maps that depict precipitation, evapotranspiration, and rates of natural recharge in Nassau and Suffolk Counties for use in future hydrologic studies on Long Island. (Author 's abstract)
Modelling the viability of heat recovery from combined sewers.

PubMed

Abdel-Aal, M; Smits, R; Mohamed, M; De Gussem, K; Schellart, A; Tait, S

2014-01-01

Modelling of wastewater temperatures along a sewer pipe using energy balance equations and assuming steady-state conditions was achieved. Modelling error was calculated, by comparing the predicted temperature drop to measured ones in three combined sewers, and was found to have an overall root mean squared error of 0.37 K. Downstream measured wastewater temperature was plotted against modelled values; their line gradients were found to be within the range of 0.9995-1.0012. The ultimate aim of the modelling is to assess the viability of recovering heat from sewer pipes. This is done by evaluating an appropriate location for a heat exchanger within a sewer network that can recover heat without impacting negatively on the downstream wastewater treatment plant (WWTP). Long sewers may prove to be more viable for heat recovery, as heat lost can be reclaimed before wastewater reaching the WWTP.
Water quality in the Mahoning River and selected tributaries in Youngstown, Ohio

USGS Publications Warehouse

Stoeckel, Donald M.; Covert, S. Alex

2002-01-01

The lower reaches of the Mahoning River in Youngstown, Ohio, have been characterized by the Ohio Environmental Protection Agency (OEPA) as historically having poor water quality. Most wastewater-treatment plants (WWTPs) in the watershed did not provide secondary sewage treatment until the late 1980s. By the late 1990s, the Mahoning River still received sewer-overflow discharges from 101 locations within the city of Youngstown, Ohio. The Mahoning River in Youngstown and Mill Creek, a principal tributary to the Mahoning River in Youngstown, have not met biotic index criteria since the earliest published assessment by OEPA in 1980. Youngstown and the OEPA are working together toward the goal of meeting water-quality standards in the Mahoning River. The U.S. Geological Survey collected information to help both parties assess water quality in the area of Youngstown and to estimate bacteria and inorganic nitrogen contributions from sewer-overflow discharges to the Mahoning River. Two monitoring networks were established in the lower Mahoning River: the first to evaluate hydrology and microbiological and chemical water quality and the second to assess indices of fish and aquatic-macroinvertebrate-community health. Water samples and water-quality data were collected from May through October 1999 and 2000 to evaluate where, when, and for how long water quality was affected by sewer-overflow discharges. Water samples were collected during dry- and wet-weather flow, and biotic indices were assessed during the first year (1999). The second year of sample collection (2000) was directed toward evaluating changes in water quality during wet-weather flow, and specifically toward assessing the effect of sewer-overflow discharges on water quality in the monitoring network. Water-quality standards for Escherichia coli (E. coli) concentration and draft criteria for nitrate plus nitrite and total phosphorus were the regulations most commonly exceeded in the Mahoning River and Mill Creek sampling networks. E. coli concentrations increased during wet-weather flow and remained higher than dry-weather concentrations for 48 hours after peak flow. E. coli concentration criteria were more commonly exceeded during wet-weather flow than during dry-weather flow. Exceedances of nutrient-concentration criteria were not substantially more common during wet-weather flow. The fish and aquatic macroinvertebrate network included Mill Creek and its tributaries but did not include the main stem of the Mahoning River. Persistent exceedances of chemical water-quality standards in Mill Creek and the presence of nutrient concentrations in excess of draft criteria may have contributed to biotic index scores that on only one occasion met State criteria throughout the fish and aquatic macroinvertebrate sampling network. Monitored tributary streams did not contribute concentrations of E. coli, nitrate plus nitrite, or total phosphorus to the Mahoning River and Mill Creek that were higher than main-stem concentrations, but monitored WWTP and sewer-overflow discharges did contribute. Twenty-four hour load estimates of sewer-overflow discharge contributions during wet-weather flow indicated that sewer-overflow discharges contributed large loads of bacteria and inorganic nitrogen to the Mahoning River relative to the instream load. The sewer-overflow loads appeared to move as a slug of highly enriched water that passed through Youngstown on the rising limb of the storm hydrograph. The median estimated sewer-overflow load contribution of bacteria was greater than the estimated instream load by a factor of five or more; however, the median estimated sewer-overflow load of inorganic nitrogen was less than half of the estimated instream load. Sewer-overflow discharges contributed loads of E. coli and nutrients to the Mahoning River and Mill Creek at a point where the streams already did not meet State water-quality regulations. Improvement of water quality of
7 CFR 1948.53 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

.... (j) Fair market value. The price at which a property will sell in the open market allowing a... or instrumentality thereof. (q) Public facilities. Installations open to the public and used for the... areas, sewer plants, water plants, community centers, libraries, city or town halls, jailhouses...
7 CFR 1948.53 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... (j) Fair market value. The price at which a property will sell in the open market allowing a... or instrumentality thereof. (q) Public facilities. Installations open to the public and used for the... areas, sewer plants, water plants, community centers, libraries, city or town halls, jailhouses...

VARIATIONS OF MICROORGANISM CONCENTRATIONS IN URBAN STORMWATER RUNOFF WITH LAND USE AND SEASONS

EPA Science Inventory

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three different land use areas based on local designation (high-density residential, low-density residential, and landscaped commercial)....
Vacuum Flushing of Sewer Solids

EPA Science Inventory

The vacuum sewer and tank cleaning (flushing) technology removes sewer solids from urban drainage systems, such as storage tanks and pipes. This technology is both effective and inexpensive. In addition, it can be considered a true green technology. It operates under atmospheri...
City sewer collectors biocorrosion

NASA Astrophysics Data System (ADS)

Ksiażek, Mariusz

2014-12-01

This paper presents the biocorrosion of city sewer collectors impregnated with special polymer sulphur binders, polymerized sulphur, which is applied as the industrial waste material. The city sewer collectors are settled with a colony of soil bacteria which have corrosive effects on its structure. Chemoautotrophic nitrifying bacteria utilize the residues of halites (carbamide) which migrate in the city sewer collectors, due to the damaged dampproofing of the roadway and produce nitrogen salts. Chemoorganotrophic bacteria utilize the traces of organic substrates and produce a number of organic acids (formic, acetic, propionic, citric, oxalic and other). The activity of microorganisms so enables the origination of primary and secondary salts which affect physical properties of concretes in city sewer collectors unfavourably.
The influence of biodegradability of sewer solids for the management of CSOs.

PubMed

Sakrabani, R; Ashley, R M; Vollertsen, J

2005-01-01

The re-suspension of sediments in combined sewers and the associated pollutants into the bulk water during wet weather flows can cause pollutants to be carried further downstream to receiving waters or discharged via Combined Sewer Overflows (CSO). A typical pollutograph shows the trend of released bulk pollutants with time but does not consider information on the biodegradability of these pollutants. A new prediction methodology based on Oxygen Utilisation Rate (respirometric method) and Erosionmeter (laboratory device replicating in-sewer erosion) experiments is proposed which is able to predict the trends in biodegradability during in-sewer sediment erosion in wet weather conditions. The proposed new prediction methodology is also based on COD fractionation techniques.
Contribution of different sources to the pollution of wet weather flows in combined sewers.

PubMed

Gromaire, M C; Garnaud, S; Saad, M; Chebbo, G

2001-02-01

Experiments performed on "Marais" catchment, in central Paris, aimed to follow up the quality of wet weather flows from the entry to the exit of a combined sewer network. SS, VSS, COD, BOD5, Cd, Cu, Pb, Zn concentrations were measured for an important number of rain events in roof, yard, street runoff, as well as in dry and wet weather flows at the catchment outlet. Mass entry-exit totals, at the scale of the catchment, were calculated over 31 rain events in order to evaluate the contribution of different types of runoff, of sanitary sewage and of sewer sediments to the total wet weather pollutant loads at the catchment outlet. The erosion of in-sewer pollutant stocks was found to be the main source of particles and of organic matter in wet weather flows, whereas heavy metal loads mainly originated from roof runoff, due to the corrosion of metallic roofs. Particles eroded inside the sewer during rain events were found to be quite different from the particles constituting the main part of sewer sediments: they are organic and biodegradable, with rather important settling velocities and seem to accumulate during dry weather periods. A change of the chemical form of heavy metals was noticed during the transport in the sewer and it is suspected that a fraction of the dissolved metals from the runoff is adsorbed on sewer sediments.
Geomorphic characteristics and classification of Duluth-area streams, Minnesota

USGS Publications Warehouse

Fitzpatrick, Faith A.; Peppler, Marie C.; DePhilip, Michele M.; Lee, Kathy E.

2006-01-01

In 2003 and 2004, a geomorphic assessment of streams in 20 watersheds in the Duluth, Minn., area was conducted to identify and summarize geomorphic characteristics, processes, disturbance mechanisms, and potential responses to disturbance. Methods used to assess the streams included watershed characterization, descriptions of segment slopes and valley types, historical aerial photograph interpretation, and rapid field assessments and intensive field surveys of stream reaches. Geomorphic conditions were summarized into a segment-scale classification with 15 categories mainly based on drainage-network position and slope, and, secondarily, based on geologic setting, valley type, and dominant geomorphic processes. Main causes of geomorphic disturbance included historical logging and agriculture, and ongoing urban development, human-caused channel alterations, road and storm sewer drainage, ditching, hiking trails, and gravel pits or quarries. Geomorphic responses to these disturbances are dependent on a combination of drainage-network position, slope, and geologic setting. Geologic setting is related to drainage-network position because the geologic deposits parallel the Lake Superior shoreline. Headwater streams in large watersheds flow over glacial deposits above altitudes of about 1,200 feet (ft). Headwater tributaries and upper main stems have ditch-like channels with gentle slopes and no valleys. Urban development and road drainage cause increased runoff and flood peaks in these segments resulting in channel widening. Below about 1,200 ft, main-stem segments generally are affected by bedrock type and structure and have steep slopes and confined or entrenched valleys. Increases in flood peaks do not cause incision or widening in the bedrock-controlled valleys; instead, the flow and scour areas are expanded. Feeder tributaries to these main stems have steep, confined valleys and may be sources for sediment from urban areas, road runoff, or storm sewer outfalls. Main-stem segments near the glacial deposits/surficial bedrock contact (1,000–1,200 ft) have the most potential for response to disturbance because they tend to have narrow valleys with sandy glacial lakeshore deposits and moderate slopes. Increases in flood peaks (from upstream increases in runoff) increase the potential for landslides and mass wasting from valley sides as well as channel widening.
Savannah River Plant engineering and design history. Volume 4: 300/700 Areas & general services and facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1957-01-01

The primary function of the 300 Area is the production and preparation of the fuel and target elements required for the 100 Area production reactors. Uranium slugs and lithium-aluminium alloy control and blanket rods are prepared in separate structures. Other facilities include a test pile, a physics assembly laboratory, an office and change house, an electrical substation, and various service facilities such as rail lines, roads, sewers, steam and water distribution lines, etc. The 700 Area contains housing and facilities for plant management, general plant services, and certain technical activities. The technical buildings include the Main Technical Laboratory, the Wastemore » Concentration Building, the Health Physics Headquarters, and the Health Physics Calibration building. Sections of this report describe the following: development of the 300-M Area; selection and description of process; design of main facilities of the 300 Area; development of the 700-A Area; design of the main facilities of the 700 Area; and general services and facilities, including transportation, plant protection, waste disposal and drainage, site work, pilot plants, storage, and furniture and fixtures.« less
Modeling and identifying the sources of radiocesium contamination in separate sewerage systems.

PubMed

Pratama, Mochamad Adhiraga; Yoneda, Minoru; Yamashiki, Yosuke; Shimada, Yoko; Matsui, Yasuto

2018-05-01

The Fukushima Dai-ichi nuclear power plant accident released radiocesium in large amounts. The released radionuclides contaminated much of the surrounding environment, including sewers in urban areas of Fukushima prefecture. In this study we attempted to identify and quantify the sources of radiocesium contamination in separate sewerage systems and developed a compartment model based on the Radionuclide Migration in Urban Environments and Drainage Systems (MUD) model. Measurements of the time-dependent radiocesium concentration in sewer sludge combined with meteorological, demographic, and radiocesium dietary intake data indicated that rainfall-derived inflow and infiltration (RDII) and human excretion were the chief contributors of radiocesium contamination in a separate sewerage system. The quantities of contamination derived from RDII and human excretion were calculated and used in the modified MUD model to simulate radiocesium contamination in sewers in three urban areas in Fukushima prefecture: Fukushima, Koriyama, and Nihonmatsu Cities. The Nash efficiency coefficient (0.88-0.92) and determination coefficient (0.89-0.93) calculated in an evaluation of our compartment model indicated that the model produced satisfactory results. We also used the model to estimate the total volume of sludge with radiocesium concentrations in excess of the clearance level, based on the number of months elapsed after the accident. Estimations by our model suggested that wastewater treatment plants (WWTPs) in Fukushima, Koriyama, and Nihonmatsu generated about 1,750,000m 3 of radioactive sludge in total, a level in good agreement with the real data. Copyright © 2017 Elsevier B.V. All rights reserved.
Vacuum Flushing of Sewer Solids (Slides)

EPA Science Inventory

The vacuum sewer and tank cleaning (flushing) technology removes sewer solids from urban drainage systems, such as storage tanks and pipes. This technology is both effective and inexpensive. In addition, it can be considered a true green technology. It operates under atmospheri...
SANITARY-SEWER OVERFLOW CONTROL STRATEGY

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary-sewer systems and their associated vast number of house-service laterals or building connections, it is often less expensive...
SURFACE FLOODS IN COIMBRA: simple and dual-drainage studies

NASA Astrophysics Data System (ADS)

Leitão, J. P.; Simões, N. E.; Pina, R.; Marques, A. Sá; Maksimović, Č.; Gonçalves, Gil

2009-09-01

Surface water flooding occurs due to extreme rainfall and the inability of the sewer system to drain all runoff. As a consequence, a considerable volume of water is carried out over the surface through preferential flow paths and can eventually accumulate in natural (or man-made) ponds. This can cause minor material losses but also major incidents with obvious consequences in economic activities and the normal people's life. Unfortunately, due to predicted climate changes and increase of urbanisation levels, the urban flooding phenomenon has been reported more often. The Portuguese city of Coimbra is a medium size city that has suffered several river floods in the past. However, after the construction of hydraulic control structures, the number of fluvial flood events was greatly reduced. In the 1990s two new problems started. On one hand, houses started to be built on flood plain areas; on the other hand, some areas experienced a boom in the degree of urbanisation. This created flood problems of a different type dislocating the flood areas from the traditional flood areas along the river to new areas that did not reported flood in history. The catchment studied has a total area of approximately 1.5 km2 and discharges in the Coselhas brook The catchment can be divided in three regions with different characteristics: (i) the "Lower City" which is a low-lying area with 0.4 km2 and with a combined sewer system; (ii) the "Upper City" which is a considerably hilly area, highly urbanized and with an area of approximately 0.2 km2; and (iii) the remaining area which is also highly urbanized, with an area of 0.9 km2, where the main flood problems are generated. The sewer system is 34.8 km long; 29 km are of the combined type, and only 1.2 km is exclusive for storm water. The time of concentration of the catchment is estimated to be 45 min. On the 9 June 2006, an extreme rainfall event caused severe flooding in the city. After the rainfall had stopped, water continued to flow along the roads towards the Praça 8 de Maio, which is the lowest point in the whole catchment and where water tends to accumulate. As presented in Table 1, the return periods calculated for durations shorter than 30 minutes are not high. In fact, this rainfall event is characterised by an extreme heavy intensity regarding its total duration; thus it cannot be considered a short period event with a high intensity. As its total duration is approximately the time of concentration of the catchment, the flooding event was very significant. A 50 year return period was estimated for the event with 45 minutes duration. Table 1: Return period interpretation of the 9 June 2006 rainfall event Duration 5 (min) 10 (min) 15 (min) 30 (min) 45 (min) Maximum rainfall intensity (mm/h)122.4 76.8 72.4 61.6 47.6 Return period1(year) 10 8 20 > 50 50 Comparing the simulation results and the actual flood locations, it is concluded that the main cause of flooding is not the capacity of the sewer system. Despite the high slopes and the high level of imperviousness of the catchment, the flood seems to be mainly caused due to the limited capacity of the sewer inlets. It suggests that the correct analysis of the hydraulic behaviour of the catchment drainage system should contemplate the analysis of the overland flow system, either using a one- (1D) or two-dimensional (2D) approaches. Hence, simulation of the 9 June 2006 event were also carried out considering the 1D sewer model, an 1D/1D model and an 1D/2D model. The methodology developed at the Imperial College London to generate overland flow networks was used in the 1D/1D model. Infoworks CS was used to do the hydraulic simulations of the 1D/1D and 1D/2D models. The results of the simulations taking into account the overland flow system will be presented in this paper. Local community reports and photos are then used to validate the simulation results obtained. Acknowledgements The authors would like to acknowledge Águas de Coimbra, E.M. and Edinfor (Portugal) for providing the data used in this study. Provision of the software used to carry out the hydraulic simulations.by Wallingford Software is also acknowledged. The first and second authors also acknowledge the financial support from the Fundação para a Ciência e Tecnologia, Portugal [SFRH/BD/21382/2005 and SFRH/BD/37797/2007].
SSOAP - A USEPA Toolbox for Sanitary Sewer Overflow Analysis and Control Planning - Presentation

EPA Science Inventory

The United States Environmental Protection Agency (USEPA) has identified a need to use proven methodologies to develop computer tools that help communities properly characterize rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems and develop sanitary sewer...
CONTROL STRATEGY FOR STORM-GENERATED SANITARY-SEWER OVERFLOWS

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary sewer systems, it is often less expensive to use alterantives to sewerline rehabilitation for infiltration/inflow (I/I) and ...
CONTROL STRATEGY FOR STORM-GENERATED SANITARY-SEWER OVERFLOWS

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary-sewer systems and their associated vast number of house-service laterals or building connections, it is often less expensiv...
Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox

EPA Science Inventory

Rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby receiving waters and can also ...
NPDES Permit for Denver Federal Center Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Denver Federal Center Municipal Separate Storm Sewer System is authorized to discharge from all municipal separate storm sewer outfalls existing as of the effective date of permit CO-R042004 to receiving waters Lakewood, Jefferson County, Colorado.
Control Strategy for Storm-Generated Sanitary Sewer Overflows

EPA Science Inventory

This presentation covers a strategy for the abatement of pollution from sanitary-sewer overflows (SSO). Because of the great lengths of sanitary sewer systems, it is often less expensive to use alternatives to sewerline rehabilitation for infiltration/inflow (I/I) and associated ...
URBAN WET-WEATHER FLOW MANAGEMENT: RESEARCH DIRECTIONS

EPA Science Inventory

There are three types of urban wet-weather flow (WWF) discharges: 1) combined-sewer overflow (CSO), which is a mixture of storm drainage and municipal-industrial wastewater discharged from combined sewers or dry-weather flow discharged from combined sewers due to clogged intercep...
Environmental Assessment for the Expansion and Consolidation of the Base Exchange at Joint Base Andrews-Naval Air Facility Washington, Prince George’s County, Maryland

DTIC Science & Technology

2013-08-01

Wildlife Service VOC volatile organic compound WG/CC Wing, Commanding Officer WSSC Washington Suburban Sanitary Commission WWTP waste water...2009a). 3.3 Infrastructure and Utilities 3.3.1 Wastewater Collection and Treatment Sanitary Sewer The sanitary sewer system at JBA was privatized...in February 2006. Terrapin Utility Services, Inc., owns and operates the sanitary sewer system (JBA-NAFW 2013). The majority of the sanitary sewer
Dynamics of rain-induced pollutographs of solubles in sewers.

PubMed

Rutsch, M; Müller, I; Krebs, P

2005-01-01

When looking at acute receiving water impacts due to combined sewer overflows the characteristics of the background diurnal sewage flux variation may influence the peak loads from combined sewer overflows (CSO) and wastewater treatment plant (WWTP) effluent significantly. In this paper, effects on the dynamic compounds transported in the sewer, on CSO discharges and WWTP loading are evaluated by means of hydrodynamic simulations. The simulations are based on different scenarios for diurnal dry-weather flow variations induced by different infiltration rates.

COMBINED SEWER OVERFLOW - BALANCING FLOW FOR CSO ABATEMENT

EPA Science Inventory

Instead of using conventional storage units, e.g., reinforced concrete tanks and lined earthen basins, which are relatively expensive and require a lot of urban land area, the in-receiving water flow balance method (FBM) facilities use the receiving water body itself for storage ...
Treatment of chromium contaminated plating shop rinsewater streams by reverse osmosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, J.F.; Brown, C.H. Jr.; Wilson, J.H.

1988-01-01

Wastewater is discharged to the local sanitary sewer, which is regulated by a Metropolitan Sewer District (MSD). The MSD has established discharge limits and reports have indicated that the major source of wastewater and primary area of concern is the discharge from the industrial plating shop within the plant complex. This plating shop generates /approximately/1100 m/sup 3/ (300,000 gal) of wastewater per day. Because construction of a new plating shop is currently planned, a complete renovation of the existing plating shop is not economically feasible. The sponsor demonstrated the use of innovative wastewater treatment technologies that will minimize the amountmore » of wastewater generated from the plating processes and maintain compliance with MSD discharge limits until the new plating shop is constructed. The problems at the facility have been analyzed and a treatment system utilizing reverse osmosis (RO), with volume reduction of the RO concentrate by evaporation, has been recommended. The utilization of RO meets the specification for the demonstration of innovative technology. This paper discusses the problem analysis at the plant as well as the results of a pilot scale RO test program currently being conducted. The installation of the full scale unit is dependent on the successful completion of the RO pilot tests. 1 ref., 6 figs., 3 tabs.« less
Fractal analysis of urban environment: land use and sewer system

NASA Astrophysics Data System (ADS)

Gires, A.; Ochoa Rodriguez, S.; Van Assel, J.; Bruni, G.; Murla Tulys, D.; Wang, L.; Pina, R.; Richard, J.; Ichiba, A.; Willems, P.; Tchiguirinskaia, I.; ten Veldhuis, M. C.; Schertzer, D. J. M.

2014-12-01

Land use distribution are usually obtained by automatic processing of satellite and airborne pictures. The complexity of the obtained patterns which are furthermore scale dependent is enhanced in urban environment. This scale dependency is even more visible in a rasterized representation where only a unique class is affected to each pixel. A parameter commonly analysed in urban hydrology is the coefficient of imperviousness, which reflects the proportion of rainfall that will be immediately active in the catchment response. This coefficient is strongly scale dependent with a rasterized representation. This complex behaviour is well grasped with the help of the scale invariant notion of fractal dimension which enables to quantify the space occupied by a geometrical set (here the impervious areas) not only at a single scale but across all scales. This fractal dimension is also compared to the ones computed on the representation of the catchments with the help of operational semi-distributed models. Fractal dimensions of the corresponding sewer systems are also computed and compared with values found in the literature for natural river networks. This methodology is tested on 7 pilot sites of the European NWE Interreg IV RainGain project located in France, Belgium, Netherlands, United-Kingdom and Portugal. Results are compared between all the case study which exhibit different physical features (slope, level of urbanisation, population density...).
A Multi-Hydro simulation for the evaluation of the hydrologic behaviour of a peri-urban catchment

NASA Astrophysics Data System (ADS)

Giangola-Murzyn, A.; Tchiguirinskaia, I.; Schertzer, D. J.; Hoang, C.

2012-12-01

In the context of the growth of the cities, the urbanized areas occupy more places in the riskier area of flood. As more and more people live in these peri-urban areas and are vulnerable to the flood risk. The understanding of this risk asks the question of the modeling of the flood. In this way, the Multi-Hydro model was developed and improved at the Ecole des Ponts ParisTech. This model consists into a coupling between four modules (relying on existing open source and widely validated physically based model): one for the rainfall scenario generation, one for the surface processes, one for the subsurface processes and one for the load of the sewer system. This structure of coupling allows to represent all the parts of the water's path from the surface to the sewer system's pipes and to the soil of the considered catchment and it allows to disconnect one element of the coupling system if it's necessary. Moreover, this model uses some GIS data as the elevation, the land use, the soil description and the sewer system description which can be managed by a dedicaded open source SIG allowing to use directly the data in the model. Considering the great amount of data needed for the model occurring, the overland water depth couldn't be relied on the survey data. However, the behaviour changes of a catchment by the changing of the land use can be evaluate by the analysis of the risk map and an advanced statistical analysis. Thus, the Multi-Hydro model was applied on a city of the Paris area: the city of Villecresnes. It is a small catchment of 0.712 square kilometer where the flood comes only from the runoff of the rainfall. This catchment is simulated with too kind of rainfall (constant or variable in space and in time) and with two kind of elevation: a "raw" elevation coming from the field survey and a "modified" elevation in function of the land use. In this last case, the elevation is increased for the houses places by 5m and decreased in the road places by 15 cm. The location of the water is controlled by the topography in the first case but it's controlled by the location of the houses in the second case. The serie of maps obtained in the both cases are analyzed by advanced statistical method (multifractals) that shown that the modification of the elevation according into the land use implies important changes on the global hydrologic behaviour of the catchment. The impact of the design of the rainfall is induced by the location of the higher intensities of the rainfall because according to the location of these higher intensities, the discharge at the outlet of the catchment can be modified.
Dissolved oxygen in gravity sewers--measurement and simulation.

PubMed

Gudjonsson, G; Vollertsen, J; Hvitved-Jacobsen, T

2002-01-01

Dissolved oxygen (DO) concentrations were during 2 months continuously measured in an intercepting sewer. Measurements were made upstream and downstream in a 3.6 km gravity sewer. DO showed significant diurnal variations mainly caused by changes in the organic matter composition of the wastewater. At low temperatures the gravity sewer was strictly aerobic. However, towards the end of the measuring campaign, DO concentrations decreased as temperature increased and the sewer became anaerobic part of the day. A conceptual model that takes into account bulk water and biofilm DO uptake as well as reaeration was used to simulate the DO measured. Using measurements from the upstream station as input, the model was calibrated to yield good validation results of the DO at the downstream station.
Multi-element sewer slime impact pattern--a quantitative characteristic enabling identification of the source of heavy metal discharges into sewer systems.

PubMed

Kintrup, J; Wünsch, G

2001-11-01

The capability of sewer slime to accumulate heavy metals from municipal wastewater can be exploited to identify the sources of sewage sludge pollution. Former investigations of sewer slime looked for a few elements only and could, therefore, not account for deviations of the enrichment efficiency of the slime or for irregularities from sampling. Results of ICP-MS multi element determinations were analyzed by multivariate statistical methods. A new dimensionless characteristic "sewer slime impact" is proposed, which is zero for unloaded samples. Patterns expressed in this data format specifically extract the information required to identify the type of pollution and polluter quicker and with less effort and cost than hitherto.
Different erosion characteristics of sediment deposits in combined and storm sewers.

PubMed

Xu, Zuxin; Wu, Jun; Li, Huaizheng; Liu, Zhenghua; Chen, Keli; Chen, Hao; Xiong, Lijun

2017-04-01

To investigate the different erosion patterns of sediments in combined and storm sewers, sediments from three separate sewer systems and two combined sewer systems in urban Shanghai were collected for the flushing experiments. These experiments were conducted with different consolidation periods and shear velocities. As the consolidation period increases, dissolved oxygen exhibits a positive effect on the microbial transformations of organic substrates. Potential structural changes and separations of the surface and bottom layers of sediments are observed. The results also reveal that the organic matter, particle size and moisture have different effects on the erosion resistance of sediments. Furthermore, illicit connections behaved as an important factor affecting the viscosity and static friction force of particles, which directly alter the erosion resistance of sewer sediments.
Hydrogen sulphide removal from corroding concrete: comparison between surface removal rates and biomass activity.

PubMed

Jensen, H S; Nielsen, A H; Lens, P N L; Hvitved-Jacobsen, T; Vollertsen, J

2009-11-01

Corrosion of concrete sewer pipes caused by hydrogen sulphide is a problem in many sewer networks. The mechanisms of production and fate of hydrogen sulphide in the sewer biofilms and wastewater as well as its release to the sewer atmosphere are largely understood. In contrast, the mechanisms of the uptake of hydrogen sulphide on the concrete surfaces and subsequent concrete corrosion are basically unknown. To shed light on these mechanisms, the uptake of hydrogen sulphide from a sewer gas phase was compared to the biological hydrogen sulphide removal potential of the concrete corrosion products. The results showed that both microbial degradation at and sorption to the concrete surfaces were important for the uptake of hydrogen sulphide on the concrete surfaces.
Propagation of radar rainfall uncertainty in urban flood simulations

NASA Astrophysics Data System (ADS)

Liguori, Sara; Rico-Ramirez, Miguel

2013-04-01

This work discusses the results of the implementation of a novel probabilistic system designed to improve ensemble sewer flow predictions for the drainage network of a small urban area in the North of England. The probabilistic system has been developed to model the uncertainty associated to radar rainfall estimates and propagate it through radar-based ensemble sewer flow predictions. The assessment of this system aims at outlining the benefits of addressing the uncertainty associated to radar rainfall estimates in a probabilistic framework, to be potentially implemented in the real-time management of the sewer network in the study area. Radar rainfall estimates are affected by uncertainty due to various factors [1-3] and quality control and correction techniques have been developed in order to improve their accuracy. However, the hydrological use of radar rainfall estimates and forecasts remains challenging. A significant effort has been devoted by the international research community to the assessment of the uncertainty propagation through probabilistic hydro-meteorological forecast systems [4-5], and various approaches have been implemented for the purpose of characterizing the uncertainty in radar rainfall estimates and forecasts [6-11]. A radar-based ensemble stochastic approach, similar to the one implemented for use in the Southern-Alps by the REAL system [6], has been developed for the purpose of this work. An ensemble generator has been calibrated on the basis of the spatial-temporal characteristics of the residual error in radar estimates assessed with reference to rainfall records from around 200 rain gauges available for the year 2007, previously post-processed and corrected by the UK Met Office [12-13]. Each ensemble member is determined by summing a perturbation field to the unperturbed radar rainfall field. The perturbations are generated by imposing the radar error spatial and temporal correlation structure to purely stochastic fields. A hydrodynamic sewer network model implemented in the Infoworks software was used to model the rainfall-runoff process in the urban area. The software calculates the flow through the sewer conduits of the urban model using rainfall as the primary input. The sewer network is covered by 25 radar pixels with a spatial resolution of 1 km2. The majority of the sewer system is combined, carrying both urban rainfall runoff as well as domestic and trade waste water [11]. The urban model was configured to receive the probabilistic radar rainfall fields. The results showed that the radar rainfall ensembles provide additional information about the uncertainty in the radar rainfall measurements that can be propagated in urban flood modelling. The peaks of the measured flow hydrographs are often bounded within the uncertainty area produced by using the radar rainfall ensembles. This is in fact one of the benefits of using radar rainfall ensembles in urban flood modelling. More work needs to be done in improving the urban models, but this is out of the scope of this research. The rainfall uncertainty cannot explain the whole uncertainty shown in the flow simulations, and additional sources of uncertainty will come from the structure of the urban models as well as the large number of parameters required by these models. Acknowledgements The authors would like to acknowledge the BADC, the UK Met Office and the UK Environment Agency for providing the various data sets. We also thank Yorkshire Water Services Ltd for providing the urban model. The authors acknowledge the support from the Engineering and Physical Sciences Research Council (EPSRC) via grant EP/I012222/1. References [1] Browning KA, 1978. Meteorological applications of radar. Reports on Progress in Physics 41 761 Doi: 10.1088/0034-4885/41/5/003 [2] Rico-Ramirez MA, Cluckie ID, Shepherd G, Pallot A, 2007. A high-resolution radar experiment on the island of Jersey. Meteorological Applications 14: 117-129. [3] Villarini G, Krajewski WF, 2010. Review of the different sources of uncertainty in single polarization radar-based estimates of rainfall. Surveys in Geophysics 31: 107-129. [4] Rossa A, Liechti K, Zappa M, Bruen M, Germann U, Haase G, Keil C, Krahe P, 2011. The COST 731 Action: A review on uncertainty propagation in advanced hydrometeorological forecast systems. Atmospheric Research 100, 150-167. [5] Rossa A, Bruen M, Germann U, Haase G, Keil C, Krahe P, Zappa M, 2010. Overview and Main Results on the interdisciplinary effort in flood forecasting COST 731-Propagation of Uncertainty in Advanced Meteo-Hydrological Forecast Systems. Proceedings of Sixth European Conference on Radar in Meteorology and Hydrology ERAD 2010. [6] Germann U, Berenguer M, Sempere-Torres D, Zappa M, 2009. REAL - ensemble radar precipitation estimation for hydrology in a mountainous region. Quarterly Journal of the Royal Meteorological Society 135: 445-456. [8] Bowler NEH, Pierce CE, Seed AW, 2006. STEPS: a probabilistic precipitation forecasting scheme which merges and extrapolation nowcast with downscaled NWP. Quarterly Journal of the Royal Meteorological Society 132: 2127-2155. [9] Zappa M, Rotach MW, Arpagaus M, Dorninger M, Hegg C, Montani A, Ranzi R, Ament F, Germann U, Grossi G et al., 2008. MAP D-PHASE: real-time demonstration of hydrological ensemble prediction systems. Atmospheric Science Letters 9, 80-87. [10] Liguori S, Rico-Ramirez MA. Quantitative assessment of short-term rainfall forecasts from radar nowcasts and MM5 forecasts. Hydrological Processes, accepted article. DOI: 10.1002/hyp.8415 [11] Liguori S, Rico-Ramirez MA, Schellart ANA, Saul AJ, 2012. Using probabilistic radar rainfall nowcasts and NWP forecasts for flow prediction in urban catchments. Atmospheric Research 103: 80-95. [12] Harrison DL, Driscoll SJ, Kitchen M, 2000. Improving precipitation estimates from weather radar using quality control and correction techniques. Meteorological Applications 7: 135-144. [13] Harrison DL, Scovell RW, Kitchen M, 2009. High-resolution precipitation estimates for hydrological uses. Proceedings of the Institution of Civil Engineers - Water Management 162: 125-135.
Rerouting Urban Waters: A Historic Examination of the Age of Imperviousness

NASA Astrophysics Data System (ADS)

Hopkins, K. G.; Bain, D. J.

2011-12-01

From the 1600's to the 1900's landscapes along the Eastern United States underwent dramatic changes, including transitions from forest to production agriculture and eventually urban development. Legacy effects from decisions on sewer and water infrastructure built during the early 1900's are emerging today in degraded urban waterways. Impervious cover is often a factor used to predict water impairment. However, does imperviousness age or change through the course of landscape evolution? This study reconstructs the history of imperviousness in the Panther Hollow watershed (161 ha, Pittsburgh, PA) to examine these changes. We reconstruct the importance of factors influencing effective imperviousness from the 1800's to present including; (1) pipe and road network technological transitions, (2) land cover changes, particularly the loss of forest cover, and (3) modifications to local topography. Analysis reveals effective imperviousness (impervious area in the basin directly connected to stream channels) increased dramatically after 1900. Prior to 1900, water and sewer infrastructure was very limited. Local drainage networks generally followed the natural topography and households accessed water supplies from wells, precipitation harvesting or surface water. Road networks were sparse and predominantly dirt or aggregate surfaces. Forests and large family farms dominated land cover. Around 1910 public water supply expanded, significantly increasing effective imperviousness due to installation of brick and ceramic sewer infrastructure that routed waste waters directly to stream channels. Road networks also expanded and began transitioning from dirt roads to brick and eventually asphalt. Shifting to impervious paving materials required the installation of stormwater drainage. New drainage systems altered historic flow paths by re-routed large quantities of water through macro-pore sewer networks to local waterways. While this improvement prevented flooding to roadways, it also created new flooding issues downstream of outfalls. Improvements to transit networks also increased mobility and connected towns together facilitating the expansion of development. Significant losses of urban tree canopy cover and the loss of water storage capacity in soils compounded issues, dramatically increasing effective imperviousness. From 1940 - 1960 concerns over polluted waterways resulted in the re-routing of sewage networks from streams to treatment facilities, decreasing sewage subsidies to effective imperviousness. However, connection of stormwater drainage networks to sewage infrastructure designed for earlier flow regimes and the increasing effective imperviousness resulted in frequent overflows of sewage directly to local waterways. Currently, aging infrastructure presents the opportunity to incorporate low impact development techniques in infrastructure repair. This has the potential to reduce effective imperviousness in urban areas by re-establishing lost hydrologic flow paths. This research indicates imperviousness as a parameter incorporates a complicated mix of processes. Examining the causal, mechanistic links between these systems can provide additional perspective on water impairments in urban landscapes throughout the course of landscape evolution.
Demonstration of Innovative Sewer System Inspection Technology SewerBatt

EPA Science Inventory

The overall objective of this EPA-funded study was to demonstrate innovative a sewer line assessment technology that is designed for rapid deployment using portable equipment. This study focused on demonstration of a technology that is suitable for smaller diameter pipes (less th...
Review of Sewer Design Criteria and RDII Prediction Methods

EPA Science Inventory

Rainfall-derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause serio...
SEWER AND TANK FLUSHING FOR CORROSION AND POLLUTION CONTROL

EPA Science Inventory

This paper presents an overview of the causes of sewer deterioration and control methods that can prevent or arrest this deterioration. articular, the paper addresses the use of inline- and combined sewer overflow (CSO) storage tank-flushing systems for removing sediments and mi...
Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and is currently one of the top national water program priorities. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox to assist communities in developing ...
SEWER AND TANK FLUSHING FOR SEDIMENT, CORROSION AND POLLUTION CONTROL

EPA Science Inventory

This paper presents an overview of causes of sewer deterioration together with a discussion of control methods that can prevent or arrest this deterioration. In particular, the paper covers inline- and combined sewer overflow- (CSO) storage-tank-flushing systems for removal of se...
Combined sewer overflow control with LID based on SWMM: an example in Shanghai, China.

PubMed

Liao, Z L; Zhang, G Q; Wu, Z H; He, Y; Chen, H

2015-01-01

Although low impact development (LID) has been commonly applied across the developed countries for mitigating the negative impacts of combined sewer overflows (CSOs) on urban hydrological environment, it has not been widely used in developing countries yet. In this paper, a typical combined sewer system in an urbanized area of Shanghai, China was used to demonstrate how to design and choose CSO control solutions with LID using stormwater management model. We constructed and simulated three types of CSO control scenarios. Our findings support the notion that LID measures possess favorable capability on CSO reduction. Nevertheless, the green scenarios which are completely comprised by LID measures fail to achieve the maximal effectiveness on CSO reduction, while the gray-green scenarios (LID measure combined with gray measures) achieve it. The unit cost-effectiveness of each type of scenario sorts as: green scenario > gray-green scenario > gray scenario. Actually, as the storage tank is built in the case catchment, a complete application of green scenario is inaccessible here. Through comprehensive evaluation and comparison, the gray-green scenario F which used the combination of storage tank, bio-retention and rain barrels is considered as the most feasible one in this case.
SEWER SEDIMENT CONTROL: AN OVERVIEW OF THE EPA WET WEATHER FLOW (WWF) RESEARCH PROGRAM

EPA Science Inventory

This paper presents an overview of EPA WWF Research Program projects related to causes of sewer solids deposition and control methods that can prevent accumulation of sewer sediments. In particular, discussion will focus on the relationship of wastewater characteristics to flow ...
SEWER-SEDIMENT CONTROL: OVERVIEW OF AN EPA WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

This paper presents a historical overview of the sewer sediment control projects conducted by the Wet-Weather Flow Research Program of the USEPA. Research presented includes studies of the causes of sewer solids deposition and development/evaluation of control methods that can pr...
COMPUTER TOOLS FOR SANITARY SEWER SYSTEM CAPACITY ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems has long been recognized as a major source of operating problems, causing poor performance of many sewer systems. RDII is the main cause of SSOs to customer basements, streets, or nearby streams and can a...
DEVELOPMENT OF SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) TOOLBOX

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams. RDII can also cause se...

SSOAP - A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause serio...
SSOAP - A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...
Sanitary Sewer Systems and Association with Gastrointestinal Illness: A case crossover analysis of Massachusetts Data, 2006-2008

EPA Science Inventory

Sanitary sewer overflows (SSOs) occur when untreated sewage is discharged into water sources before reaching the treatment facility potentially contaminating them with gastrointestinal pathogens. Causes of SSOs include heavy rainfall and rupture/blockage of sewer lines. Few studi...
Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox - slides

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and is currently one of the top national water program priorities. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox to assist communities in developing S...
INNOVATIVE METHODS FOR THE OPTIMIZATION OF GRAVITY STORM SEWER DESIGN

EPA Science Inventory

The purpose of this paper is to describe a new method for optimizing the design of urban storm sewer systems. Previous efforts to optimize gravity sewers have met with limited success because classical optimization methods require that the problem be well behaved, e.g. describ...
A Review of Advanced Sewer System Design Technologies (WERF Report INFR4SG09d)

EPA Science Inventory

Abstract: This document seeks to collect into one place current and new technologies about sewerage system design. The document organizes the information found in the 295 documents that were reviewed into six subject areas: Advanced Onsite Technologies; Alternative Wastewater C...
Fighting Downtown: A Training Necessity for the Heavy Brigade

DTIC Science & Technology

2001-02-01

Concept Technology Demonstration, and the Army Transformation Urban Franchise exploration of future operations.”57 CAMTF has identified three...fighting in a downtown area with tall buildings and underground sewers and or subways , but it must also apply to the outlying urban sprawl that is now
Sewer Maintenance Manual.

ERIC Educational Resources Information Center

Ontario Ministry of the Environment, Toronto.

Outlined are practices and procedures that should be followed in order to protect and fully realize the benefits of sewer systems and also to maximize service and minimize inconveniences to the public. Written in practical terms, the manual is designed to be of immediate use to municipal employees and others involved in sewer maintenance…
GATE AND VACUUM FLUSHING OF SEWER SEDIMENT: LABORATORY TESTING

EPA Science Inventory

The objective of this study was to test the performance of a traditional gate-flushing device and a newly-designed vacuum-flushing device in removing sediment from combined sewers and CSO storage tanks. A laboratory hydraulic flume was used to simulate a reach of sewer or storag...
Update on the Status of Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox

EPA Science Inventory

A properly designed, operated and maintained sanitary sewer system is meant to collect and convey all of the sewage that flows into it to a wastewater treatment plant. However, occasional unintentional discharges of raw sewage from municipal sanitary sewers – called sanitary sewe...
A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) AND APPLICATIONS

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...
78 FR 20316 - Draft Small Municipal Separate Storm Sewer System NPDES General Permit-New Hampshire; Extension...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9799-1] Draft Small Municipal Separate Storm Sewer System NPDES General Permit--New Hampshire; Extension of Comment Period AGENCY: Environmental Protection Agency... draft Small Municipal Separate Storm Sewer System (MS4) National Pollutant Discharge Elimination System...
78 FR 27964 - Draft Small Municipal Separate Storm Sewer System NPDES General Permit-New Hampshire; Extension...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-13

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9812-8] Draft Small Municipal Separate Storm Sewer System NPDES General Permit--New Hampshire; Extension of Comment Period AGENCY: Environmental Protection Agency... draft Small Municipal Separate Storm Sewer System (MS4) National Pollutant Discharge Elimination System...
HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of gate flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...
Flood Grouting for Infiltration Reduction on Private Side Sewers (WERF Report INFR5R11)

EPA Science Inventory

The sewers in Seattle’s Broadview neighborhood, built in the 1950s, experience significant inflow and infiltration. Intense wet weather events have resulted in sewer overflows into private residences and the environment and previous work indicates that the majority of this excess...
Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox - abstract

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and it is currently one of the top national water program priorities, and is one of the top priorities of the U.S. Conference of Mayors. The U.S. Environmental Protection Agency developed the Sanitary Sewer Overflow Analysis a...
HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE-FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of gate-flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...
SEWER SEDIMENT GATE AND VACUUM FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of a traditional gate-flushing device and a newly designed vacuum-flushing device in removing sediments from combined sewers and CSO storage tanks. A laboratory hydraulic flune was used to simulate a reach of sewer or storag...
40 CFR 35.2130 - Sewer use ordinance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...
40 CFR 35.2130 - Sewer use ordinance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...

Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and it is currently one of the top national water program priorities, and is one of the top priorities of the U.S. Conference of Mayors. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Anal...
Infiltration and hydraulic connections from the Niagara River to a fractured-dolomite aquifer in Niagara Falls, New York

USGS Publications Warehouse

Yager, R.M.; Kappel, W.M.

1998-01-01

The spatial distribution of hydrogen and oxygen stable-isotope values in groundwater can be used to distinguish different sources of recharge and to trace groundwater flow directions from recharge boundaries. This method can be particularly useful in fractured-rock settings where multiple lines of evidence are required to delineate preferential flow paths that result from heterogeneity within fracture zones. Flow paths delineated with stable isotopes can be combined with hydraulic data to form a more complete picture of the groundwater flow system. In this study values of ??D and ??18O were used to delineate paths of river-water infiltration into the Lockport Group, a fractured dolomite aquifer, and to compute the percentage of fiver water in groundwater samples from shallow bedrock wells. Flow paths were correlated with areas of high hydraulic diffusivity in the shallow bedrock that were delineated from water-level fluctuations induced by diurnal stage fluctuations in man-made hydraulic structures. Flow paths delineated with the stable-isotope and hydraulic data suggest that fiver infiltration reaches an unlined storm sewer in the bedrock through a drainage system that surrounds aqueducts carrying river water to hydroelectric power plants. This finding is significant because the storm sewer is the discharge point for contaminated groundwater from several chemical waste-disposal sites and the cost of treating the storm sewer's discharge could be reduced if the volume of infiltration from the river were decreased.The spatial distribution of hydrogen and oxygen stable-isotope values in groundwater can be used to distinguish different sources of recharge and to trace groundwater flow directions from recharge boundaries. This method can be particularly useful in fractured-rock settings where multiple lines of evidence are required to delineate preferential flow paths that result from heterogeneity within fracture zones. Flow paths delineated with stable isotopes can be combined with hydraulic data to form a more complete picture of the groundwater flow system. In this study values of ??D and ??18O were used to delineate paths of river-water infiltration into the Lockport Group, a fractured dolomite aquifer, and to compute the percentage of river water in groundwater samples from shallow bedrock wells. Flow paths were correlated with areas of high hydraulic diffusivity in the shallow bedrock that were delineated from water-level fluctuations induced by diurnal stage fluctuations in man-made hydraulic structures. Flow paths delineated with the stable-isotope and hydraulic data suggest that river infiltration reaches an unlined storm sewer in the bedrock through a drainage system that surrounds aqueducts carrying river water to hydroelectric power plants. This finding is significant because the storm sewer is the discharge point for contaminated groundwater from several chemical waste-disposal sites and the cost of treating the storm sewer's discharge could be reduced if the volume of infiltration from the river were decreased.
Field campaign on sediment transport behaviour in a pressure main from pumping station to wastewater treatment plant in Berlin.

PubMed

Gunkel, M; Pawlowsky-Reusing, E

2017-05-01

As part of the project KURAS, the Berliner Wasserbetriebe realized a field campaign in 2015 in order to increase the process knowledge regarding the behaviour of transported sediment in the pressure main leading from the pumpstation to the wastewater treatment plant. The field campaign was conducted because of a lack of knowledge about the general condition of the pressure main due to its bad accessibility and the suspicion of deposits caused by hydraulic underload. The practical evidence of the sediment transport performance of this part of the sewer system, dependent on different load cases, should present a basis for further analysis, for example regarding flushing measures. A positive side-effect of the investigation was the description of the amount of pollutants caused by different weather conditions in combined sewer systems and the alterations of the sewage composition due to biogenic processes during transport. The concept included the parallel sampling of the inflow at the pumpstation and the outflow at the end of the pressure main during different weather conditions. By calculating the inflow to the pressure main, as well as its outflow at different flow conditions, it was possible to draw conclusions in regard to the transport behaviour of sediment and the bioprocesses within an 8.5 km section of the pressure main. The results show clearly that the effects of sedimentation and remobilization depend on the flow conditions. The balance of the total suspended solids (TSS) load during daily variations in dry weather shows that the remobilization effect during the run-off peak is not able to compensate for the period of sedimentation happening during the low flow at night. Based on the data for dry weather, an average of 238 kg of TSS deposits in the pressure main remains per day. The remobilization of sediment occurs only due to the abruptly increased delivery rates caused by precipitation events. These high pollution loads lead to a sudden strain at the wastewater treatment plant. It was found that the sediment transport behaviour is characterized by sedimentation up to a flow velocity of 0.35 m/s, while remobilization effects occur above 0.5 m/s. The assumption of bad sediment transport performance in the pressure main was confirmed. Therefore, the results can be used as a basis for further analysis, for example regarding periodical flushing as a means of cleaning the pressure main. The findings, especially regarding the methods and processes, are transferable and can be applied to other pressure mains in combined sewer systems. Besides the outlined evaluation of the sediment transport behaviour of the pressure main, the collected data were used in the project to calibrate a sewer system model, including a water quality model for the catchment area, and as a contribution towards an early physically based sediment transport modelling in InfoWorks CS.
Real time control of a combined sewer system using radar-measured precipitation--results of the pilot study.

PubMed

Petruck, A; Holtmeier, E; Redder, A; Teichgräber, B

2003-01-01

Emschergenossenschaft and Lippeverband have developed a method to use radar-measured precipitation as an input for a real-time control of a combined sewer system containing several overflow structures. Two real-time control strategies have been developed and tested, one is solely volume-based, the other is volume and pollution-based. The system has been implemented in a pilot study in Gelsenkirchen, Germany. During the project the system was optimised and is now in constant operation. It was found, that the volume of combined sewage overflow could be reduced by 5 per cent per year. This was also found in simulations carried out in similar catchment areas. Most of the potential of improvement can already be achieved by local pollution-based control strategies.
Statistically based sustainable re-design of stormwater overflow control systems in urban catchments

NASA Astrophysics Data System (ADS)

Ganora, Daniele; Isacco, Silvia; Claps, Pierluigi

2017-04-01

Control and reduction of pollution from stormwater overflow is a major concern for municipalities to manage the quality of the receiving water bodies according to the Framework Water Directive 2000/60/CE. In this regard, assessment studies of the potential pollution load from sewer networks recognize the need for adaptation and upgrade of existing drainage systems, which can be achieved with either traditional water works (detention tanks, increase of wastewater treatment plant capacity, etc.) or even Nature-based solutions (constructed wetlands, restored floodplains, etc.) sometimes used in combination. Nature-based solutions are recently receiving consistent attentions as they are able to enhance urban and degraded environments being, in the same time, more resilient and adaptable to climatic and anthropic changes than most traditional engineering works. On the other hand, restoration of the urban environment using natural absorbing surfaces requires diffuse interventions, high costs and a considerable amount of time. In this work we investigate how simple, economically-sustainable and quick solutions to the problem at hand can be addressed by changes in the management rules when pumping stations play a role in sewer systems. In particular, we provide a statistically-based framework to be used in the calibration of the management rules, facing improved quality of overflows from sewer systems. Typical pumping rules favor a massive delivery of stormwater volumes to the wastewater treatment plans, requiring large storage tanks in the sewer network, heavy pumping power and reducing the efficiency of the treatment plant due to pollutant dilution. In this study we show that it is possible to optimize the pumping rule in order to reduce pumped volumes to the plant (thus saving energy), while simultaneously keeping high pollutant concentration. On the other hand, larger low-concentration overflow volumes are released outside the sewer network with respect to the standard pumping rules. Such released volumes could be efficiently processed by nature-based solutions, like for instance constructed wetlands, to reduce the final pollutant impact on the environment. The proposed procedure is based on the previous knowledge of the precipitation forcing and of a quantity/quality model of the sewer network. The method provides marginal and joint probability distributions of water volumes and pollutant concentration (or mass) delivered toward the wastewater treatment plant and the Nature-based system, with the aim of supporting a more efficient design of the whole sewer system. A practical example of application is provided for illustrative purposes.
Effects of precipitation events on virus presence in groundwater

USDA-ARS?s Scientific Manuscript database

Previous studies by our group have demonstrated the presence of human enteric viruses in groundwater, and that leakage from sanitary sewers is a likely source of such contamination in urban areas. This work showed high rates of virus detection, and that virus detection was positively correlated with...
Appalachian Regional Commission: 1987 Annual Report.

ERIC Educational Resources Information Center

Russell, Jack, Ed.; And Others

The Appalachian Regional Commission (ARC) used its $105 million appropriation for fiscal year 1987 to support three major program areas in the 13 state region: (1) creating and retaining regional jobs; (2) assisting in construction of basic facilities, particularly water and sewer systems, in the region's 90 poorest counties; and (3) working…
WATER INFRASTRUCTURE IN THE 21ST CENTURY: U.S. EPA’S RESEARCH PLANS FOR GRAVITY SEWERS

EPA Science Inventory

The U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD) has long recognized the need for research and development in the area of drinking water and wastewater infrastructure. Most recently in support of the Agency’s Sustainable Water Infrastruct...
Quality Assurance and Quality Control Practices for Rehabilitation of Sewer and Water Mains

EPA Science Inventory

As part of the US Environmental Protection Agency (EPA)’s Aging Water Infrastructure Research Program, several areas of research are being pursued, including a review of quality assurance and quality control (QA/QC) practices and acceptance testing during the installation of reha...
Quality Assurance and Quality Control Practices For Rehabilitation of Sewer and Water Mains

EPA Science Inventory

As part of the US Environmental Protection Agency (EPA)’s Aging Water Infrastructure Research Program, several areas of research are being pursued including a review of quality assurance and quality control (QA/QC) practices and acceptance testing during the installation of rehab...
Assessing the Impacts of Pulp Loading from Non-Dispersible Materials on Downstream Sewer Systems (WERF Report INFR1R14)

EPA Science Inventory

Abstract:This study subjected wipes from five different manufacturers to a variety of tests to determine if changes to their physical characteristics occur when introduced into a sewer systemand what effect the shredded material (pulp) has on the downstream sewer. Shredded and no...
Final Environmental Assessment for the Disposal of the Former Lynn Haven Fuel Depot, Tyndall Air Force Base, Florida

DTIC Science & Technology

2015-12-01

groundwater), infrastructure/utilities (i.e., sanitary sewer, potable water, solid waste management, drainage, transportation systems, electricity and...on water resources (i.e., surface water and groundwater), infrastructure/utilities (i.e., sanitary sewer, potable water, solid waste management...3-8 3.3.6.4 Sanitary Sewer
40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...
40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...
40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...
40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...
40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...
7. VIEW TO NORTH SHOWING SEWER CONSTRUCTION IN FOREGROUND AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW TO NORTH SHOWING SEWER CONSTRUCTION IN FOREGROUND AND BUILDING F IN THE LEFT BACKGROUND. 8X10 black and white gelatin print. United States Coast Guard, Air Station Contract 1247, Sewer System. 1956. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA
Simplifying impact of urban development on sewer systems.

PubMed

Kleidorfer, Manfred; Sitzenfrei, Robert; Rauch, Wolfgang

2014-01-01

Linking urban development and urban drainage models is a more and more popular approach when impacts of pavement of urban areas on sewer system performance are evaluated. As such an approach is a difficult task, this is not a feasible procedure for everyday engineering practice. We propose an alternative method, based on a developed simple near-quadratic relationship, which directly translates change (increase or decrease) of paved area into a change in the return period (RP) of the design rainfall event or design rainfall intensity. This formula is simple to use and compatible with existing design guidelines. A further advantage is that the calculated design RP can also be used to communicate the impact of a change in impervious areas to stakeholders or the public community. The method is developed using a set of 250 virtual and two real-world case studies and hydrodynamic simulations. It is validated on a small catchment for which we compare system performance and redesigned pipe diameters. Of course such a simplification contains different uncertainties. But these uncertainties have to be seen in the context of overall uncertainties when trying to predict city development into the future. Hence it still is a significant advantage compared to today's engineering practice.
Cluster analysis for characterization of rainfalls and CSO behaviours in an urban drainage area of Tokyo.

PubMed

Yu, Yang; Kojima, Keisuke; An, Kyoungjin; Furumai, Hiroaki

2013-01-01

Combined sewer overflow (CSO) from urban areas is recognized as a major pollutant source to the receiving waters during wet weather. This study attempts to categorize rainfall events and corresponding CSO behaviours to reveal the relationship between rainfall patterns and CSO behaviours in the Shingashi urban drainage areas of Tokyo, Japan where complete service by a combined sewer system (CSS) and CSO often takes place. In addition, outfalls based on their annual overflow behaviours were characterized for effective storm water management. All 117 rainfall events recorded in 2007 were simulated by a distributed model InfoWorks CS to obtain CSO behaviours. The rainfall events were classified based on two sets of parameters of rainfall pattern as well as CSO behaviours. Clustered rainfall and CSO groups were linked by similarity analysis. Results showed that both small and extreme rainfalls had strong correlations with the CSO behaviours, while moderate rainfall had a weak relationship. This indicates that important and negligible rainfalls from the viewpoint of CSO could be identified by rainfall patterns, while influences from the drainage area and network should be taken into account when estimating moderate rainfall-induced CSO. Additionally, outfalls were finally categorized into six groups indicating different levels of impact on the environment.

The Distribution and Movement of American Cockroaches in Urban Niches of New Orleans.

PubMed

Carlson, John C; Rabito, Felicia A; Werthmann, Derek; Fox, Mark

2017-10-01

American cockroaches are an important source of household allergens in tropical and semitropical climates. To determine which outdoor niches produce American cockroaches, traps were placed at 40 homes in New Orleans to collect nymphs. Nymphs were collected from the sewers, yards, and within the homes themselves. To compare sewers and yards as sources of cockroaches entering homes, adult cockroaches were collected, marked, and released into yards and sewers. No sewer-released cockroaches were collected in homes. Cockroaches released into yards were collected in the homes, suggesting that yards, rather than sewers, are a more important source niche. A field trial applying boric acid granules to the yard was performed in an effort to reduce entry of cockroaches. There was a significant reduction in the cockroach antigen collected in intervention homes compared with controls.
Assessment of the contribution of sewer deposits to suspended solids loads in combined sewer systems during rain events.

PubMed

Hannouche, A; Chebbo, G; Joannis, C

2014-04-01

Within the French observatories network SOERE "URBIS," databases of continuous turbidity measurements accumulating hundreds of events and many dry weather days are available for two sites with different features (Clichy in Paris and Ecully in Lyon). These measurements, converted into total suspended solids (TSS) concentration using TSS-turbidity relationships and combined with a model of runoff event mean concentration, enable the assessment of the contribution of sewer deposits to wet weather TSS loads observed at the outlet of the two watersheds. Results show that the contribution of sewer deposits to wet weather suspended solid's discharges is important but variable (between 20 and 80 % of the mass at the outlet depending on the event), including a site allegedly free of (coarse) sewer deposits. The uncertainties associated to these results are assessed too.
Impacts and managerial implications for sewer systems due to recent changes to inputs in domestic wastewater - A review.

PubMed

Mattsson, Jonathan; Hedström, Annelie; Ashley, Richard M; Viklander, Maria

2015-09-15

Ever since the advent of major sewer construction in the 1850s, the issue of increased solids deposition in sewers due to changes in domestic wastewater inputs has been frequently debated. Three recent changes considered here are the introduction of kitchen sink food waste disposers (FWDs); rising levels of inputs of fat, oil and grease (FOG); and the installation of low-flush toilets (LFTs). In this review these changes have been examined with regard to potential solids depositional impacts on sewer systems and the managerial implications. The review indicates that each of the changes has the potential to cause an increase in solids deposition in sewers and this is likely to be more pronounced for the upstream reaches of networks that serve fewer households than the downstream parts and for specific sewer features such as sags. The review has highlighted the importance of educational campaigns directed to the public to mitigate deposition as many of the observed problems have been linked to domestic behaviour in regard to FOGs, FWDs and toilet flushing. A standardized monitoring procedure of repeat sewer blockage locations can also be a means to identify depositional hot-spots. Interactions between the various changes in inputs in the studies reviewed here indicated an increased potential for blockage formation, but this would need to be further substantiated. As the precise nature of these changes in inputs have been found to be variable, depending on lifestyles and type of installation, the additional problems that may arise pose particular challenges to sewer operators and managers because of the difficulty in generalizing the nature of the changes, particularly where retrofitting projects in households are being considered. The three types of changes to inputs reviewed here highlight the need to consider whether or not more or less solid waste from households should be diverted into sewers. Copyright © 2015 Elsevier Ltd. All rights reserved.
A dynamic ventilation model for gravity sewer networks.

PubMed

Wang, Y C; Nobi, N; Nguyen, T; Vorreiter, L

2012-01-01

To implement any effective odour and corrosion control technology in the sewer network, it is imperative that the airflow through gravity sewer airspaces be quantified. This paper presents a full dynamic airflow model for gravity sewer systems. The model, which is developed using the finite element method, is a compressible air transport model. The model has been applied to the North Head Sewerage Ocean Outfall System (NSOOS) and calibrated using the air pressure and airflow data collected during October 2008. Although the calibration is focused on forced ventilation, the model can be applied to natural ventilation as well.
A combined model to assess technical and economic consequences of changing conditions and management options for wastewater utilities.

PubMed

Giessler, Mathias; Tränckner, Jens

2018-02-01

The paper presents a simplified model that quantifies economic and technical consequences of changing conditions in wastewater systems on utility level. It has been developed based on data from stakeholders and ministries, collected by a survey that determined resulting effects and adapted measures. The model comprises all substantial cost relevant assets and activities of a typical German wastewater utility. It consists of three modules: i) Sewer for describing the state development of sewer systems, ii) WWTP for process parameter consideration of waste water treatment plants (WWTP) and iii) Cost Accounting for calculation of expenses in the cost categories and resulting charges. Validity and accuracy of this model was verified by using historical data from an exemplary wastewater utility. Calculated process as well as economic parameters shows a high accuracy compared to measured parameters and given expenses. Thus, the model is proposed to support strategic, process oriented decision making on utility level. Copyright © 2017 Elsevier Ltd. All rights reserved.
Simulation of ground-water flow in the Potomac-Raritan-Magothy aquifer system near the Defense Supply Center Philadelphia, and the Point Breeze Refinery, southern Philadelphia County, Pennsylvania

USGS Publications Warehouse

Schreffler, Curtis L.

2001-01-01

Ground-water flow in the Potomac-Raritan- Magothy aquifer system (PRM) in south Philadelphia and adjacent southwestern New Jersey was simulated by use of a three-dimensional, seven-layer finite-difference numerical flow model. The simulation was run from 1900, which was prior to groundwater development, through 1995 with 21 stress periods. The focus of the modeling was on a smaller area of concern in south Philadelphia in the vicinity of the Defense Supply Center Philadelphia (DSCP) and the Point Breeze Refinery (PBR). In order to adequately simulate the ground-water flow system in the area of concern, a much larger area was modeled that included parts of New Jersey where significant ground-water withdrawals, which affect water levels in southern Philadelphia, had occurred in the past. At issue in the area of concern is a hydrocarbon plume of unknown origin and time of release.The ground-water-flow system was simulated to estimate past water-level altitudes in and near the area of concern and to determine the effect of the Packer Avenue sewer, which lies south of the DSCP, on the ground-water-flow system. Simulated water-level altitudes for the lower sand unit of the PRM on the DSCP prior to 1945 ranged from pre-development, unstressed altitudes to 3 feet below sea level. Simulated water-level altitudes for the lower sand unit ranged from 3 to 7 feet below sea level from 1946 to 1954, from 6 to 10 feet below sea level from 1955 to 1968, and from 9 to 11 feet below sea level from 1969 to 1978. The lowest simulated water-level altitude on the DSCP was 10.69 feet below sea level near the end of 1974. Model simulations indicate ground water was infiltrating the Packer Avenue sewer prior to approximately 1947 or 1948. Subsequent to that time, simulated ground-water-level altitudes were lower than the bottom of the sewer.
Modelling total suspended solids, E. coli and carbamazepine, a tracer of wastewater contamination from combined sewer overflows

NASA Astrophysics Data System (ADS)

Pongmala, Khemngeun; Autixier, Laurène; Madoux-Humery, Anne-Sophie; Fuamba, Musandji; Galarneau, Martine; Sauvé, Sébastien; Prévost, Michèle; Dorner, Sarah

2015-12-01

Urban source water protection requires knowledge of sources of fecal contamination upstream of drinking water intakes. Combined and sanitary sewer overflows (CSOs and SSOs) are primary sources of microbiological contamination and wastewater micropollutants (WWMPs) in urban water supplies. To quantify the impact of sewer overflows, predictive simulation models are required and have not been widely applied for microbial contaminants such as fecal indicator bacteria and pathogens in urban drainage networks. The objective of this study was to apply a simulation model to estimate the dynamics of three contaminants in sewer overflows - total suspended solids, Escherichia coli (E. coli) and carbamazepine, a WWMP. A mixed combined and pseudo-sanitary drainage network in Québec, Canada was studied and modelled for a total of 7 events for which water quality data were available. Model results were significantly correlated with field water quality data. The model confirmed that the contributions of E. coli from runoff and sewer deposits were minor and their dominant source was from sewage. In contrast, the main sources of total suspended solids were stormwater runoff and sewer resuspension. Given that it is not present in stormwater, carbamazepine was found to be a useful stable tracer of sewage contributions to total contaminant loads and also provided an indication of the fraction of total suspended solids originating from sewer deposits because of its similar response to increasing flowrates.
243 E. Ontario Street - Sewer, Lindsay Light Radiological Survey

EPA Pesticide Factsheets

The field gamma measurements within the excavation during the excavation process did not exceed theinstrument threshold previously stated, and ranged from a minimum of 1,100 cpm to a maximum of 3,600cpm shielded.
75 FR 5788 - Notice of Availability of Draft National Pollutant Discharge Elimination System (NPDES) General...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-04

... Discharge Elimination System (NPDES) General Permits for Small Municipal Separate Storm Sewer Systems (MS4... at 40 CFR 122.26(b)(16) define a small municipal separate storm sewer system as ``* * * all separate storm sewers that are: (1) Owned or operated by the United States, a State, city, town, borough, county...
On the occurrence of rainstorm damage based on home insurance and weather data

NASA Astrophysics Data System (ADS)

Spekkers, M. H.; Clemens, F. H. L. R.; ten Veldhuis, J. A. E.

2014-08-01

Rainstorm damage caused by malfunctioning of urban drainage systems and water intrusion due to defects in the building envelope can be considerable. Little research on this topic focused on the collection of damage data, the understanding of damage mechanisms and the deepening of data analysis methods. In this paper, the relative contribution of different failure mechanisms to the occurrence of rainstorm damage are investigated, as well as the extent to which these mechanisms relate to weather variables. For a case study in Rotterdam, the Netherlands, a property level home insurance database of around 3100 water-related damage claims was analysed. Records include comprehensive transcripts of communication between insurer, insured and damage assessment experts, which allowed claims to be classified according to their actual damage cause. Results show that roof and wall leakage is the most frequent failure mechanism causing precipitation-related claims, followed by blocked roof gutters, melting snow and sewer flooding. Claims related to sewer flooding were less present in the data, but are associated with significantly larger claim sizes than claims in the majority class, i.e. roof and wall leakages. Rare events logistic regression analysis revealed that maximum rainfall intensity and rainfall volume are significant predictors for the occurrence probability of precipitation-related claims. Moreover, it was found that claims associated with rainfall intensities smaller than 7-8 mm in a 60 min window are mainly related to failures processes in the private domain, such as roof and wall leakages. For rainfall events that exceed the 7-8 mm h-1 threshold, failure of systems in the public domain, such as sewer systems, start to contribute considerably to the overall occurrence probability of claims. The communication transcripts, however, lacked information to be conclusive about to extent to which sewer-related claims were caused by overloading of sewer systems or failure of system components.
On the occurrence of rainstorm damage based on home insurance and weather data

NASA Astrophysics Data System (ADS)

Spekkers, M. H.; Clemens, F. H. L. R.; ten Veldhuis, J. A. E.

2015-02-01

Rainstorm damage caused by the malfunction of urban drainage systems and water intrusion due to defects in the building envelope can be considerable. Little research on this topic focused on the collection of damage data, the understanding of damage mechanisms and the deepening of data analysis methods. In this paper, the relative contribution of different failure mechanisms to the occurrence of rainstorm damage is investigated, as well as the extent to which these mechanisms relate to weather variables. For a case study in Rotterdam, the Netherlands, a property level home insurance database of around 3100 water-related damage claims was analysed. The records include comprehensive transcripts of communication between insurer, insured and damage assessment experts, which allowed claims to be classified according to their actual damage cause. The results show that roof and wall leakage is the most frequent failure mechanism causing precipitation-related claims, followed by blocked roof gutters, melting snow and sewer flooding. Claims related to sewer flooding were less present in the data, but are associated with significantly larger claim sizes than claims in the majority class, i.e. roof and wall leakages. Rare events logistic regression analysis revealed that maximum rainfall intensity and rainfall volume are significant predictors for the occurrence probability of precipitation-related claims. Moreover, it was found that claims associated with rainfall intensities smaller than 7-8 mm in a 60-min window are mainly related to failure processes in the private domain, such as roof and wall leakages. For rainfall events that exceed the 7-8 mm h-1 threshold, the failure of systems in the public domain, such as sewer systems, start to contribute considerably to the overall occurrence probability of claims. The communication transcripts, however, lacked information to be conclusive about to which extent sewer-related claims were caused by overloading of sewer systems or failure of system components.
The utilisation of engineered invert traps in the management of near bed solids in sewer networks.

PubMed

Ashley, R M; Tait, S J; Stovin, V R; Burrows, R; Framer, A; Buxton, A P; Blackwood, D J; Saul, A J; Blanksby, J R

2003-01-01

Large existing sewers are considerable assets which wastewater utilities will require to operate for the foreseeable future to maintain health and the quality of life in cities. Despite their existence for more than a century there is surprisingly little guidance available to manage these systems to minimise problems associated with in-sewer solids. A joint study has been undertaken in the UK, to refine and utilise new knowledge gained from field data, laboratory results and Computational Fluid Dynamics (CFD) simulations to devise cost beneficial engineering tools for the application of small invert traps to localise the deposition of sediments in sewers at accessible points for collection. New guidance has been produced for trap siting and this has been linked to a risk-cost-effectiveness assessment procedure to enable system operators to approach in-sewer sediment management pro-actively rather than reactively as currently happens.
RTC simulations on large branched sewer systems with SmaRTControl.

PubMed

de Korte, Kees; van Beest, Dick; van der Plaat, Marcel; de Graaf, Erno; Schaart, Niels

2009-01-01

In The Netherlands many large branched sewer systems exist. RTC can improve the performance of these systems. The objective of the universal algorithm of SmaRTControl is to improve the performance of the sewer system and the WWTP. The effect of RTC under rain weather flow conditions is simulated using a hydrological model with 19 drainage districts. The system related inefficiency coefficient (SIC) is introduced for assessment of the performance of sewer systems. The performance can be improved by RTC in combination with increased pumping capacities in the drainage districts, but without increasing the flow to the WWTP. Under dry weather flow conditions the flow to the WWTP can be equalized by storage of wastewater in the sewer system. It is concluded that SmaRTControl can improve the performance, that simulations are necessary and that SIC is an excellent parameter for assessment of the performance.
40 CFR 63.1094 - What waste streams are exempt from the requirements of this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... CATEGORIES (CONTINUED) National Emission Standards for Ethylene Manufacturing Process Units: Heat Exchange... section are exempt from this subpart. (a) Waste in the form of gases or vapors that is emitted from process fluids. (b) Waste that is contained in a segregated storm water sewer system. Waste Requirements ...
Integrating retention soil filters into urban hydrologic models - Relevant processes and important parameters

NASA Astrophysics Data System (ADS)

Bachmann-Machnik, Anna; Meyer, Daniel; Waldhoff, Axel; Fuchs, Stephan; Dittmer, Ulrich

2018-04-01

Retention Soil Filters (RSFs), a form of vertical flow constructed wetlands specifically designed for combined sewer overflow (CSO) treatment, have proven to be an effective tool to mitigate negative impacts of CSOs on receiving water bodies. Long-term hydrologic simulations are used to predict the emissions from urban drainage systems during planning of stormwater management measures. So far no universally accepted model for RSF simulation exists. When simulating hydraulics and water quality in RSFs, an appropriate level of detail must be chosen for reasonable balancing between model complexity and model handling, considering the model input's level of uncertainty. The most crucial parameters determining the resultant uncertainties of the integrated sewer system and filter bed model were identified by evaluating a virtual drainage system with a Retention Soil Filter for CSO treatment. To determine reasonable parameter ranges for RSF simulations, data of 207 events from six full-scale RSF plants in Germany were analyzed. Data evaluation shows that even though different plants with varying loading and operation modes were examined, a simple model is sufficient to assess relevant suspended solids (SS), chemical oxygen demand (COD) and NH4 emissions from RSFs. Two conceptual RSF models with different degrees of complexity were assessed. These models were developed based on evaluation of data from full scale RSF plants and column experiments. Incorporated model processes are ammonium adsorption in the filter layer and degradation during subsequent dry weather period, filtration of SS and particulate COD (XCOD) to a constant background concentration and removal of solute COD (SCOD) by a constant removal rate during filter passage as well as sedimentation of SS and XCOD in the filter overflow. XCOD, SS and ammonium loads as well as ammonium concentration peaks are discharged primarily via RSF overflow not passing through the filter bed. Uncertainties of the integrated simulation of the sewer system and RSF model mainly originate from the model parameters of the hydrologic sewer system model.
Assessing the Role of Sewers and Atmospheric Deposition as Nitrate Contamination Sources to Urban Surface Waters using Stable Nitrate Isotopes

NASA Astrophysics Data System (ADS)

Sikora, M. T.; Elliott, E. M.

2009-12-01

Excess nitrate (NO3-) contributes to the overall degraded quality of streams in many urban areas. These systems are often dominated by impervious surfaces and storm sewers that can route atmospherically deposited nitrogen, from both wet and dry deposition, to waterways. Moreover, in densely populated watersheds there is the potential for interaction between urban waterways and sewer systems. The affects of accumulated nitrate in riverine and estuary systems include low dissolved oxygen, loss of species diversity, increased mortality of aquatic species, and general eutrophication of the waterbody. However, the dynamics of nitrate pollution from each source and it’s affect on urban waterways is poorly constrained. The isotopes of nitrogen and oxygen in nitrate have been proven effective in helping to distinguish contamination sources to ground and surface waters. In order to improve our understanding of urban nitrate pollution sources and dynamics, we examined nitrate isotopes (δ15N and δ18O) in base- and stormflow samples collected over a two-year period from a restored urban stream in Pittsburgh, Pennsylvania (USA). Nine Mile Run drains a 1,600 hectare urban watershed characterized by 38% impervious surface cover. Prior work has documented high nitrate export from the watershed (~19 kg NO3- ha-1 yr-1). Potential nitrate sources to the watershed include observed sewer overflows draining directly to the stream, as well as atmospheric deposition (~23 kg NO3- ha-1 yr-1). In this and other urban systems with high percentages of impervious surfaces, there is likely minimal input from nitrate derived from soil or fertilizer. In this presentation, we examine spatial and temporal patterns in nitrate isotopic composition collected at five locations along Nine Mile Run characterized by both sanitary and combined-sewer cross-connections. Preliminary isotopic analysis of low-flow winter streamwater samples suggest nitrate export from Nine Mile Run is primarily influenced by inputs of human waste despite high rates of atmospheric nitrate deposition. Further isotopic analysis of nitrate will examine seasonal variations in nitrate sources; compare nitrate dynamics and sources during low- versus high-flows, and the influence of interannual climatic variability on nitrate export.
Short-term microbial release during rain events from on-site sewers and cattle in a surface water source.

PubMed

Aström, Johan; Pettersson, Thomas J R; Reischer, Georg H; Hermansson, Malte

2013-09-01

The protection of drinking water from pathogens such as Cryptosporidium and Giardia requires an understanding of the short-term microbial release from faecal contamination sources in the catchment. Flow-weighted samples were collected during two rainfall events in a stream draining an area with on-site sewers and during two rainfall events in surface runoff from a bovine cattle pasture. Samples were analysed for human (BacH) and ruminant (BacR) Bacteroidales genetic markers through quantitative polymerase chain reaction (qPCR) and for sorbitol-fermenting bifidobacteria through culturing as a complement to traditional faecal indicator bacteria, somatic coliphages and the parasitic protozoa Cryptosporidium spp. and Giardia spp. analysed by standard methods. Significant positive correlations were observed between BacH, Escherichia coli, intestinal enterococci, sulphite-reducing Clostridia, turbidity, conductivity and UV254 in the stream contaminated by on-site sewers. For the cattle pasture, no correlation was found between any of the genetic markers and the other parameters. Although parasitic protozoa were not detected, the analysis for genetic markers provided baseline data on the short-term faecal contamination due to these potential sources of parasites. Background levels of BacH and BacR makers in soil emphasise the need to including soil reference samples in qPCR-based analyses for Bacteroidales genetic markers.
Modeling the Hydrologic Effects of Large-Scale Green Infrastructure Projects with GIS

NASA Astrophysics Data System (ADS)

Bado, R. A.; Fekete, B. M.; Khanbilvardi, R.

2015-12-01

Impervious surfaces in urban areas generate excess runoff, which in turn causes flooding, combined sewer overflows, and degradation of adjacent surface waters. Municipal environmental protection agencies have shown a growing interest in mitigating these effects with 'green' infrastructure practices that partially restore the perviousness and water holding capacity of urban centers. Assessment of the performance of current and future green infrastructure projects is hindered by the lack of adequate hydrological modeling tools; conventional techniques fail to account for the complex flow pathways of urban environments, and detailed analyses are difficult to prepare for the very large domains in which green infrastructure projects are implemented. Currently, no standard toolset exists that can rapidly and conveniently predict runoff, consequent inundations, and sewer overflows at a city-wide scale. We demonstrate how streamlined modeling techniques can be used with open-source GIS software to efficiently model runoff in large urban catchments. Hydraulic parameters and flow paths through city blocks, roadways, and sewer drains are automatically generated from GIS layers, and ultimately urban flow simulations can be executed for a variety of rainfall conditions. With this methodology, users can understand the implications of large-scale land use changes and green/gray storm water retention systems on hydraulic loading, peak flow rates, and runoff volumes.
75 FR 67960 - Notice of Availability of Draft National Pollutant Discharge Elimination System (NPDES) General...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-04

... Discharge Elimination System (NPDES) General Permits for Small Municipal Separate Storm Sewer Systems (MS4... requirements of the CWA. The regulations at 40 CFR 122.26(b)(16) define a small municipal separate storm sewer system as ``* * * all separate storm sewers that are: (1) Owned or operated by the United States, a State...
Hydrocarbon pollution fixed to combined sewer sediment: a case study in Paris.

PubMed

Rocher, Vincent; Garnaud, Stéphane; Moilleron, Régis; Chebbo, Ghassan

2004-02-01

Over a period of two years (2000-2001), sediment samples were extracted from 40 silt traps (STs) spread through the combined sewer system of Paris. All sediment samples were analysed for physico-chemical parameters (pH, organic matter content, grain size distribution), with total hydrocarbons (THs) and 16 polycyclic aromatic hydrocarbons (PAHs) selected from the priority list of the US-EPA. The two main objectives of the study were (1) to determine the hydrocarbon contamination levels in the sediments of the Paris combined sewer system and (2) to investigate the PAH fingerprints in order to assess their spatial variability and to elucidate the PAH origins. The results show that there is some important inter-site and intra-site variations in hydrocarbon contents. Despite this variability, TH and PAH contamination levels (50th percentile) in the Parisian sewer sediment are estimated at 530 and 18 microg g(-1), respectively. The investigation of the aromatic compound distributions in all of the 40 STs has underlined that there is, at the Paris sewer system scale, a homogeneous PAH background pollution. Moreover, the study of the PAH fingerprints, using specific ratios, suggests the predominance of a pyrolytic origin for those PAHs fixed to the sewer sediment.

INNOVATION AND RESEARCH FOR WATER INFRASTRUCTURE IN THE 21ST CENTURY: U.S. EPA'S RESEARCH PLAN FOR GRAVITY SEWERS

EPA Science Inventory

The U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD) has long recognized the need for research and development in the area of drinking water and wastewater infrastructure. Most recently in support of the Agency’s Sustainable Water Infrastructu...
INNOVATION AND RESEARCH FOR WATER INFRASTRUCTURE IN THE 21ST CENTURY: U.S. EPAS RESEARCH PLANS FOR GRAVITY SEWERS

EPA Science Inventory

The U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD) has long recognized the need for research and development in the area of drinking water and wastewater infrastructure. Most recently in support of the Agency’s Sustainable Water ...
The hydraulic capacity of deteriorating sewer systems.

PubMed

Pollert, J; Ugarelli, R; Saegrov, S; Schilling, W; Di Federico, V

2005-01-01

Sewer and wastewater systems suffer from insufficient capacity, construction flaws and pipe deterioration. Consequences are structural failures, local floods, surface erosion and pollution of receiving waters bodies. European cities spend in the order of five billion Euro per year for wastewater network rehabilitation. This amount is estimated to increase due to network ageing. The project CARE-S (Computer Aided RE-habilitation of Sewer Networks) deals with sewer and storm water networks. The final project goal is to develop integrated software, which provides the most cost-efficient system of maintenance, repair and rehabilitation of sewer networks. Decisions on investments in rehabilitation often have to be made with uncertain information about the structural condition and the hydraulic performance of a sewer system. Because of this, decision-making involves considerable risks. This paper presents the results of research focused on the study of hydraulic effects caused by failures due to temporal decline of sewer systems. Hydraulic simulations are usually carried out by running commercial models that apply, as input, default values of parameters that strongly influence results. Using CCTV inspections information as dataset to catalogue principal types of failures affecting pipes, a 3D model was used to evaluate their hydraulic consequences. The translation of failures effects in parameters values producing the same hydraulic conditions caused by failures was carried out through the comparison of laboratory experiences and 3D simulations results. Those parameters could be the input of 1D commercial models instead of the default values commonly inserted.
Separate and combined sewer systems: a long-term modelling approach.

PubMed

Mannina, Giorgio; Viviani, Gaspare

2009-01-01

Sewer systems convey mostly dry weather flow, coming from domestic and industrial sanitary sewage as well as infiltration flow, and stormwater due to meteoric precipitations. Traditionally, in urban drainage two types of sewer systems are adopted: separate and combined sewers. The former convey dry and wet weather flow separately into two different networks, while the latter convey dry and wet weather flow together. Which is the best solution in terms of cost-benefit analysis still remains a controversial subject. The present study was aimed at comparing the pollution loads discharged to receiving bodies by Wastewater Treatment Plant (WWTP) and Combined Sewer Overflow (CSO) for different kinds of sewer systems (combined and separate). To accomplish this objective, a comparison between the two systems was carried out using results from simulations of catchments characterised by different dimensions, population densities and water supply rate. The analysis was based on a parsimonious mathematical model able to simulate the sewer system as well as the WWTP during both dry and wet weather. The rain series employed for the simulations was six years long. Several pollutants, both dissolved and particulate, were modelled. The results confirmed the uncertainties in the choice of one system versus the other, emphasising the concept that case-by-case solutions have to be undertaken. Further, the compared systems showed different responses in terms of effectiveness in reducing the discharged mass to the RWB in relation to the particular pollutant taken into account.
Resilience of sewage services to climate change uncertainty: analysis of the management of sewer overflows in two Parisian suburban areas.

NASA Astrophysics Data System (ADS)

Rioust, E.; Deroubaix, J. F.; Barroca, B.; Bonierbale, T.; de Gouvello, B.; Deutsch, J. C.; Hubert, G.

2009-04-01

This paper considers the resilience perspective as an approach for understanding social and political vulnerabilities of urban services. The authors examine to what extend uncertainty due to climate change may affect the resilience of these urban services. The resilience perspective is increasingly used for analysing social groups' capacities to adapt to and live with disturbances. A lot of work on resilience has focused on the capacity to absorb shocks and still maintain functions. But there is also another aspect of resilience, which leads to take into account systems vulnerabilities and to aim at understanding their equilibrium and re-organization capacity. The purpose with this paper is to assess sewage systems capacities to adapt to climate change. Indeed, climate change could cause an increase of extreme rain events and, as a matter of consequence, an increase of sewer overflows and flooding of urbanised areas. Sewer systems have to cope with this change that may gravely affect urban planning. In recent studies of political science, risk management has been considered as a public policy involving and resulting from complex social, political and technical processes (Gilbert et al. 2003). From this point of view, the management of wastewaters and storm waters has to be considered not only as a technical but also as a political and a social system. Therefore, political science can be a fruitful perspective to understand the stakeholders perceptions of uncertainty and the way they are going to integrate this issue in their practices. The authors analyse the adaptive capacities of two sewer systems located in the Parisian suburban area. The chosen areas are highly populated. Each network is managed within a political and administrative unit called "Département". Both authorities of these "Départements" implement a public sewage service. Nonetheless these networks are connected and part of the greater Paris sewage policy. In both areas a real time control of urban wastewater systems has been developed. At last, both sewage services have make flood management their prior objective. Both "Départements" have developed retention capacities. One of them has implemented a source control strategy including daywatering while the other one has intent on building up a "culture of risk" on the territory. In this paper we compare how these social and technical systems cope with risks and face to climate change. Relying on interviews conducted with engineers and technical agents of water and sewage services and with a few residents in the concerned areas, we define three types of actors who take part to the social and technical systems. There are, on the one hand, the technical actors, including the agents currently managing the sewer network. On the other hand, there are the political actors in charge of elaborating and implementing a policy of risk prevention and managing the security force. Last but not least, there are the inhabitants who take an important part in the crisis management and in the mobilisations against the existing risk policy. The first part of the paper describes the sewage systems while there is no crisis. We explicit the actors' perceptions of risk and the risk management strategies they develop. The risk perceptions of technicians are truly different than the citizens' ones. For the technicians, floods, and their possible worsening, could be controlled. The problem is generated by the increasing impervious areas but it can be solved with technologies (real time control, best management practices and compensatory measures). In the technicians' perceptions, the risk is inherent to technical failures and can be reduced. For citizens, the concern is more for economics and personal goods losses. However both types of actors deal with the matter of submerged territories as a problem of institutional inertia (lack of financial resource, problem of governance). The second part presents the crisis management in these areas. We explain how various actors cope with flood when the risk occurs. The analysis of the actors' reaction to the flood event contributes (1) to further characterise the social and political system dealing with the flooding risk and, (2) to assess the adaptive capacities of the technicians to the risk. The crisis moment gives a specific role for each actor of the social, political and technical systems. Technical actors manage natural hazard through the remote control system and their major concern is for network disruption. Once flood has occurred, they may assist residents cleaning out public space. Nonetheless, after the crisis, the technical actors are seen by the others as the responsible for the flood. They are considered as the ones in charge of preventing the future flood event, even if they claim that they cannot protect urban areas and population up to a determined risk threshold. Neither technicians nor other actor settle the question of urban planning or existing vulnerability of the flooded areas.
Smart Water Conservation System for Irrigated Landscape

DTIC Science & Technology

2016-05-01

purple pipe indicating reuse water) and properly labeled “not for human consumption”; • Do not connect rainwater overflow discharge to sanitary sewer...Report Smart Water Conservation System 75 May 2016 Condensate Capture If redirecting condensate from sanitary sewer, ensure sewer gases are managed...the spring/early summer to determine optimum irrigation safety factor. Irrigate at night or early morning. Set soak and cycle for clay soils. ET
Sewer Project Remedies ‘Third World’ Conditions

EPA Pesticide Factsheets

An EPA-funded project to process sewage from homes on a West Virginia hillside has resolved what a county health department report described as “Third World” conditions caused by failing or non-existent on-site systems to manage human waste.
Quality of Wisconsin stormwater, 1989-94

USGS Publications Warehouse

Bannerman, Roger T.; Legg, Andrew D.; Greb, Steven R.

1996-01-01

Water-quality data were compiled from four urban stormwater monitoring projects conducted in Wisconsin between 1989 and 1994. These projects included monitoring in both storm-sewer pipes and urban streams. A total of 147 constitu ents were analyzed for in stormwater sampled from 10 storm-sewer pipes and four urban streams. Land uses represented by the storm-sewer watersheds included residential, commercial, industrial, and mixed. For about one-half the con stituents, at least 10 percent of the event mean con centrations exceeded the laboratory's minimum reporting limit. Detection frequencies were greater than 75 percent for many of the heavy metals and polycyclic aromatic hydrocarbons in both the storm sewer and stream samples, whereas detec tion frequencies were about 20 percent or greater for many of the pesticides in both types of sam ples. Stormwater concentrations for conventional constituents, such as suspended solids, chloride, total phosphorus, and fecal coliform bacteria were greater than minimum reporting limits almost 100 percent of the time. Concentrations of many of the constituents were high enough to say that stormwater in the storm sewers and urban streams might be contrib uting to the degradation of the streams. In this report, constituents defined as potential contami nants are those for which the laboratory minimum report limit was exceeded for at least 10 percent of the sampled storm events, and for which at least one event mean concentration exceeded an estab lished water-quality standard. Storm-sewer sam ples had event mean concentrations of lead, copper, zinc, cadmium, and silver that frequently exceeded Wisconsin's acute toxicity criteria for cold water fisheries. Wisconsin's human cancer criteria was exceeded almost 100 percent of the time for polycyclic aromatic hydrocarbons in stormwater samples from storm sewers and streams. Maximum concentrations of diazinon found in storm sewers exceeded recommended levels of diazinon. Storm-sewer samples also exceeded Wisconsin's ground-water enforcement standards for pesticides, PCB's, phthalates, and chloride. Defined by criteria in this report, poten tial contaminants included five metals (lead, zinc, copper, silver, and cadmium), nine polycyclic aro matic hydrocarbons, Bis(2-ethylhexyl)phthalate, four pesticides (DDT, atrazine, alachlor, and 2,4 D), suspended solids, chlorides, total phosphorus, BOD 5-day, and bacteria. Wisconsin stormwater quality was similar to stormwater quality monitored in other states. Nearly one-half of median concentrations of con stituents in Wisconsin stormwater were within 30 percent of the medians from other states. The clos est agreement was seen for biochemical oxygen demand, total phosphorus, and total recoverable zinc. Similarities in stormwater quality for the storm sewer and urban streams indicated the storm sewers were a major source of water to the streams during storm events. Concentrations of potential contaminants in urban streams increased dramati cally during storm events as compared to baseflow concentrations.
Multi-Hydro: a multi module physically based model to evaluate effect of implementation of the flood resilience measure.

NASA Astrophysics Data System (ADS)

Giangola-Murzyn, A.; Gires, A.; Richard, J.; Tchiguirinskaia, I.; Schertzer, D.

2012-04-01

Nowadays cities are rapidly growing, gradually transforming the nearby rural area into peri-urban area where the urbanization rate increases again and again. Many of these areas are located in the floodplain. In this context and to facilitate the choice of the protection measure of the building of these areas, the European SMARTeST project (Smart Resilient Technologies and System Tools) aims to create a guideline regrouping the different existing system and their conditions of use for different situations. In this context, the Multi-Hydro model was improved and tested to evaluate the effect of the implementation of the flood resilience measures. This model consists of a coupling between different modules relying on existing and validated hydrological and physically based models for runoff processes, sewer system discharge and subsurface processes. The basic data are rainfall and GIS data of elevation, land use or soil description. However, the data necessary to perform this type of model can be difficult to access. These missing data, which can be evaluated by average values, can cause inaccuracies in the simulated water levels. But if the water level cannot yet able to be connected to survey measurements, the location of this water is very useful to understand the hydrological behavior of the study area. The ability to circle the missing data enables the portability of the model, which is a major advantage for the SMARTeST project. Multi-Hydro can be thus a tool useable by all project partners. The model was implemented on a case study of the Paris area, the city of Villecresnes. Various scenarios in terms of implementation of protection measures are tested under a fixed rainfall scenario. The results of these simulations, analyzed as series of risk maps and by an advanced statistical analysis, show that depending on the selected measures (single barrier or perimeter), the behavior of the watershed is modified. Indeed, the modifications of the land use of the catchment cause a change in the location of the outlet of it. Furthermore, these changes create a new repartition of the overland water: before the implementation of the protection measures, the water is routed via the thalweg defined by the elevation to the outlet which is the lower point of the catchment, whereas after this implementation, the water route and the outlet are define by the free surfaces. Concerning the sewer system discharge, the changes in the land use didn't create significant change in the load of it.
Dynamics of pollutant discharge in combined sewer systems during rain events: chance or determinism?

PubMed

Hannouche, A; Chebbo, G; Joannis, C

2014-01-01

A large database of continuous flow and turbidity measurements cumulating data on hundreds of rain events and dry weather days from two sites in Paris (called Quais and Clichy) and one in Lyon (called Ecully) is presented. This database is used to characterize and compare the behaviour of the three sites at the inter-events scale. The analysis is probed through three various variables: total volumes and total suspended solids (TSS) masses and concentrations during both wet and dry weather periods in addition to the contributions of diverse-origin sources to event flow volume and TSS load values. The results obtained confirm the previous findings regarding the spatial consistency of TSS fluxes and concentrations between both sites in Paris having similar land uses. Moreover, masses and concentrations are proven to be correlated between Parisian sites in a way that implies the possibility of some deterministic processes being reproducible from one catchment to another for a particular rain event. The results also demonstrate the importance of the contribution of wastewater and sewer deposits to the total events' loads and show that such contributions are not specific to Paris sewer networks.
Occurrence and sources of Escherichia coli in metropolitan St. Louis streams, October 2004 through September 2007

USGS Publications Warehouse

Wilkison, Donald H.; Davis, Jerri V.

2010-01-01

The occurrence and sources of Escherichia coli (E. coli), one of several fecal indicator bacteria, in metropolitan St. Louis streams known to receive nonpoint source runoff, occasional discharges from combined and sanitary sewers, and treated wastewater effluent were investigated from October 2004 through September 2007. Three Missouri River sites, five Mississippi River sites, and six small basin tributary stream sites were sampled during base flow and storm events for the presence of E. coli and their sources. E. coli host-source determinations were conducted using local library based genotypic methods. Human fecal contamination in stream samples was additionally confirmed by the presence of Bacteroides thetaiotaomicron, an anaerobic, enteric bacterium with a high occurrence in, and specificity to, humans. Missouri River E. coli densities and loads during base flow were approximately 10 times greater than those in the Mississippi River above its confluence with the Missouri River. Although substantial amounts of E. coli originated from within the study area during base flow and storm events, considerable amounts of E. coli in the Missouri River, as well as in the middle Mississippi River sections downstream from its confluence with the Missouri River, originated in Missouri River reaches upstream from the study area. In lower Mississippi River reaches, bacteria contributions from the numerous combined and sanitary sewer overflows within the study area, as well as contributions from nonpoint source runoff, greatly increased instream E. coli densities. Although other urban factors cannot be discounted, average E. coli densities in streams were strongly correlated with the number of upstream combined and sanitary sewer overflow points, and the percentage of upstream impervious cover. Small basin sites with the greatest number of combined and sanitary sewer overflows (Maline Creek and the River des Peres) had larger E. coli densities, larger loads, and a greater percentage of E. coli attributable to humans than other small basin sites; however, even though small basin E. coli densities typically were much larger than in large river receiving streams, small basins contributed, on average, only a small part (a maximum of 16 percent) of the total E. coli load to larger rivers. On average, approximately one-third of E. coli in metropolitan St. Louis streams was identified as originating from humans. Another one-third of the E. coli was determined to have originated from unidentified sources; dogs and geese contributed lesser amounts, 10 and 20 percent, of the total instream bacteria. Sources of E. coli were largely independent of hydrologic conditions-an indication that sources remained relatively consistent with time.
Predicting the Probability of Failure of Cementitious Sewer Pipes Using Stochastic Finite Element Method

PubMed Central

Alani, Amir M.; Faramarzi, Asaad

2015-01-01

In this paper, a stochastic finite element method (SFEM) is employed to investigate the probability of failure of cementitious buried sewer pipes subjected to combined effect of corrosion and stresses. A non-linear time-dependant model is used to determine the extent of concrete corrosion. Using the SFEM, the effects of different random variables, including loads, pipe material, and corrosion on the remaining safe life of the cementitious sewer pipes are explored. A numerical example is presented to demonstrate the merit of the proposed SFEM in evaluating the effects of the contributing parameters upon the probability of failure of cementitious sewer pipes. The developed SFEM offers many advantages over traditional probabilistic techniques since it does not use any empirical equations in order to determine failure of pipes. The results of the SFEM can help the concerning industry (e.g., water companies) to better plan their resources by providing accurate prediction for the remaining safe life of cementitious sewer pipes. PMID:26068092
Suitable flow pattern increases the removal efficiency of nitrogen in gravity sewers: a suitable anoxic and aerobic environment in biofilms.

PubMed

He, Qiang; Yin, Feixian; Li, Hong; Wang, Yinliang; Xu, Jingwei; Ai, Hainan

2018-03-25

The sewers have the function of carbon removal, which has been proven. But if the effect of nitrogen removal can be enhanced at the same time of carbon removal, it can lay a foundation for the realization of "sewer's working as a reactor." This paper investigated the effects of shear stress and C/N ratio on nitrogen removal through biofilms on the sewer inner wall and nitrogen transfer. The main conclusions are as follows: (1) nitrogen could be partially removed in sewers after a series of reactions; (2) the anaerobic, anoxic, aerobic environment and some bacteria related to nitrogen metabolism, which exist in the biofilm, promote the nitrification and denitrification; (3) a total of 722 functional genes involved in nitrogen metabolism were detected in the biofilm (C/N ratio of 10, shear stress of 1.4 Pa), accounting for 0.67% of all genes, and the functional genes related to denitrification were dominant. Graphical abstract ᅟ.
Space-Derived Sewer Monitor

NASA Technical Reports Server (NTRS)

1982-01-01

The QuadraScan Longterm Flow Monitoring System is a second generation sewer monitor developed by American Digital Systems, Inc.'s founder Peter Petroff. Petroff, a former spacecraft instrumentation designer at Marshall Space Flight Center, used expertise based on principles acquired in Apollo and other NASA programs. QuadraScan borrows even more heavily from space technology, for example in its data acquisition and memory system derived from NASA satellites. "One-time" measurements are often plagued with substantial errors due to the flow of groundwater absorbed into the system. These system sizing errors stem from a basic informational deficiency: accurate, reliable data on how much water flows through a sewer system over a long period of time is very difficult to obtain. City officials are turning to "permanent," or long-term sewer monitoring systems. QuadraScan offers many advantages to city officials such as the early warning capability to effectively plan for city growth in order to avoid the crippling economic impact of bans on new sewer connections in effect in many cities today.
Output-feedback control of combined sewer networks through receding horizon control with moving horizon estimation

NASA Astrophysics Data System (ADS)

Joseph-Duran, Bernat; Ocampo-Martinez, Carlos; Cembrano, Gabriela

2015-10-01

An output-feedback control strategy for pollution mitigation in combined sewer networks is presented. The proposed strategy provides means to apply model-based predictive control to large-scale sewer networks, in-spite of the lack of measurements at most of the network sewers. In previous works, the authors presented a hybrid linear control-oriented model for sewer networks together with the formulation of Optimal Control Problems (OCP) and State Estimation Problems (SEP). By iteratively solving these problems, preliminary Receding Horizon Control with Moving Horizon Estimation (RHC/MHE) results, based on flow measurements, were also obtained. In this work, the RHC/MHE algorithm has been extended to take into account both flow and water level measurements and the resulting control loop has been extensively simulated to assess the system performance according different measurement availability scenarios and rain events. All simulations have been carried out using a detailed physically based model of a real case-study network as virtual reality.
Impact of in-Sewer Degradation of Pharmaceutical and Personal Care Products (PPCPs) Population Markers on a Population Model.

PubMed

O'Brien, Jake William; Banks, Andrew Phillip William; Novic, Andrew Joseph; Mueller, Jochen F; Jiang, Guangming; Ort, Christoph; Eaglesham, Geoff; Yuan, Zhiguo; Thai, Phong K

2017-04-04

A key uncertainty of wastewater-based epidemiology is the size of the population which contributed to a given wastewater sample. We previously developed and validated a Bayesian inference model to estimate population size based on 14 population markers which: (1) are easily measured and (2) have mass loads which correlate with population size. However, the potential uncertainty of the model prediction due to in-sewer degradation of these markers was not evaluated. In this study, we addressed this gap by testing their stability under sewer conditions and assessed whether degradation impacts the model estimates. Five markers, which formed the core of our model, were stable in the sewers while the others were not. Our evaluation showed that the presence of unstable population markers in the model did not decrease the precision of the population estimates providing that stable markers such as acesulfame remained in the model. However, to achieve the minimum uncertainty in population estimates, we propose that the core markers to be included in population models for other sites should meet two additional criteria: (3) negligible degradation in wastewater to ensure the stability of chemicals during collection; and (4) < 10% in-sewer degradation could occur during the mean residence time of the sewer network.
Understanding the spatial formation and accumulation of fats, oils and grease deposits in the sewer collection system.

PubMed

Dominic, Christopher Cyril Sandeep; Szakasits, Megan; Dean, Lisa O; Ducoste, Joel J

2013-01-01

Sanitary sewer overflows are caused by the accumulation of insoluble calcium salts of fatty acids, which are formed by the reaction between fats, oils and grease (FOG) and calcium found in wastewaters. Different sewer structural configurations (i.e., manholes, pipes, wet wells), which vary spatially, along with other obstructions (roots intrusion) and pipe deformations (pipe sags), may influence the detrimental buildup of FOG deposits. The purpose of this study was to quantify the spatial variation in FOG deposit formation and accumulation in a pilot-scale sewer collection system. The pilot system contained straight pipes, manholes, roots intrusion, and a pipe sag. Calcium and oil were injected into the system and operated at alkaline (pH = 10) and neutral (pH = 7) pH conditions. Results showed that solid accumulations were slightly higher at neutral pH. Fourier transform infrared (FTIR) analysis on the solids samples confirmed that the solids were indeed calcium-based fatty acid salts. However, the fatty acid profiles of the solids deviated from the profile found from FOG deposits in sewer systems, which were primarily saturated fatty acids. These results confirm the work done previously by researchers and suggest an alternative fate of unsaturated fatty acids that does not lead to their incorporation in FOG deposits in full-scale sewer systems.
A case independent approach on the impact of climate change effects on combined sewer system performance.

PubMed

Kleidorfer, M; Möderl, M; Sitzenfrei, R; Urich, C; Rauch, W

2009-01-01

Design and construction of urban drainage systems has to be done in a predictive way, as the average lifespan of such investments is several decades. The design engineer has to predict many influencing factors and scenarios for future development of a system (e.g. change in land use, population, water consumption and infiltration measures). Furthermore, climate change can cause increased rain intensities which leads to an additional impact on drainage systems. In this paper we compare the behaviour of different performance indicators of combined sewer systems when taking into account long-term environmental change effects (change in rainfall characteristics, change in impervious area and change in dry weather flow). By using 250 virtual case studies this approach is--in principle--a Monte Carlo Simulation in which not only parameter values are varied but the entire system structure and layout is changed in each run. Hence, results are more general and case-independent. For example the consideration of an increase of rainfall intensities by 20% has the same effect as an increase of impervious area of +40%. Such an increase of rainfall intensities could be compensated by infiltration measures in current systems which lead to a reduction of impervious area by 30%.
Watershed Scale Impacts of Stormwater Green Infrastructure on Hydrology, Nitrogen Fluxes, and Combined Sewer Overflows in the Baltimore, MD and Washington, DC area

EPA Science Inventory

Despite the increasing use of urban stormwater green infrastructure (SGI), including detention ponds and rain gardens, few studies have quantified the cumulative effects of multiple SGI projects on hydrology and water quality at the watershed scale. To assess the effects of SGI, ...
The Transformation of a River--From "Sewer" to Suburbs in 20 Years.

ERIC Educational Resources Information Center

Conniff, Richard

1990-01-01

Presents the emerging dilemma presented by the restoration of the Connecticut River ecosystem after the passage of the Clean Air Act of 1972. Cites troubles stemming from conservation efforts that made the area more appealing to developers and for recreation usage. Discusses the need for a new approach to land-use regulations. (MCO)

PROCESS DESIGN MANUAL: SURFACE DISPOSAL OF SEWAGE SLUDGE AND DOMESTIC SEPTAGE

EPA Science Inventory

Human domestic activities generate wastewater that is piped into municipal sewer systems, underground septic tanks, or portable sanitation devices. Wastewater in municipal systems is treated before being discharged into the environment, as required under the Clean Water Act. This...
Assessing the Relationship between Socioeconomic Conditions and Urban Environmental Quality in Accra, Ghana

PubMed Central

Fobil, Julius; May, Juergen; Kraemer, Alexander

2010-01-01

The influence of socioeconomic status (SES) on health inequalities is widely known, but there is still poor understanding of the precise relationship between area-based socioeconomic conditions and neighborhood environmental quality. This study aimed to investigate the socioeconomic conditions which predict urban neighbourhood environmental quality. The results showed wide variation in levels of association between the socioeconomic variables and environmental conditions, with strong evidence of a real difference in environmental quality across the five socioeconomic classes with respect to total waste generation (p < 0.001), waste collection rate (p < 0.001), sewer disposal rate (p < 0.001), non-sewer disposal (p < 0.003), the proportion of households using public toilets (p = 0.005). Socioeconomic conditions are therefore important drivers of change in environmental quality and urban environmental interventions aimed at infectious disease prevention and control if they should be effective could benefit from simultaneous implementation with other social interventions. PMID:20195437
[Study on the characteristics of combined sewer overflow from the high density residential area in Shanghai].

PubMed

Li, He; Li, Tian

2006-08-01

The urban non-point pollution has become main pollution resource of urban water bodies of Shanghai. Character of combined sewer overflow from watershed SA in Shanghai was studied, and the correlation of influence factors to the EMCs of overflows was discussed. It is found that the EMCs of COD, BOD, SS, NH3-N, TN, TP are 614 mg/L, 208.5 mg/L, 684 mg/L, 17.6 mg/L, 29.8 mg/L, 3.0 mg/L respectively, and the values obtained herein are much higher than the documented data from other countries. From the probability plot of the EMCs, it is found that the BOD has the best fitness for lognormal distribution; and correlation between the EMCs of COD, SS and the ratio of antecedent dry weather time to rain duration is quite good.
Developments in a methodology for the design of engineered invert traps in combined sewer systems.

PubMed

Buxton, A; Tait, S; Stovin, V; Saul, A

2002-01-01

Sediments within sewers can have a significant effect on the operation of the sewer system and on the surrounding natural and urban environment. One possible method for the management of sewer sediments is the use of slotted invert traps. Although invert traps can be used to selectively trap only inorganic bedload material, little is known with regard to the design of these structures. This paper presents results from a laboratory investigation comparing the trapping performance of three slot size configurations of a laboratory-scale invert trap. The paper also presents comparative results from a two-dimensional computational model utilising stochastic particle tracking. This investigation shows that particle tracking consistently over-predicts sediment retention efficiencies observed within the laboratory model.
Effects of combined-sewer overflows and urban runoff on the water quality of Fall Creek, Indianapolis, Indiana

USGS Publications Warehouse

Martin, Jeffrey D.

1995-01-01

Concentrations of dissolved oxygen measured at the station in the middle of the combined-sewer overflows were less than the Indiana minimum ambient water-quality standard of 4.0 milligrams per liter during all storms. Concentrations of ammonia, oxygen demand, copper, lead, zinc, and fecal coliform bacteria at the stations downstream from the combined-sewer overflows were much higher in storm runoff than in base flow. Increased concentrations of oxygen demand in runoff probably were caused by combined-sewer overflows, urban runoff, and the resuspension of organic material deposited on the streambed. Some of the increased concentrations of lead, zinc, and probably copper can be attributed to the discharge and resuspension of filter backwash
ENVIRONMENTAL TECHNOLOGY VERIFICATION OF URBAN RUNOFF MODELS

EPA Science Inventory

This paper will present the verification process and available results of the XP-SWMM modeling system produced by XP-Software conducted unde the USEPA's ETV Program. Wet weather flow (WWF) models are used throughout the US for the evaluation of storm and combined sewer systems. M...
Municipal gravity sewers: an unrecognised source of nitrous oxide

EPA Science Inventory

Nitrous oxide (N2O) is a primary ozone-depleting substance and powerful greenhouse gas. N2O emissions from secondary-level wastewater treatment processes are relatively well understood as a result of intensive international research effort in recent times, yet little information...
Assessment of pH shock as a method for controlling sulfide and methane formation in pressure main sewer systems.

PubMed

Gutierrez, Oriol; Sudarjanto, Gatut; Ren, Guo; Ganigué, Ramon; Jiang, Guangming; Yuan, Zhiguo

2014-01-01

Caustic dosing to raise pH above 10.0 for short periods (hours) is often used by water utilities for controlling sulfide formation in sewers. However the effectiveness of this strategy is rarely reported and the impact of pH level and exposure time on the effectiveness is largely unknown. The effectiveness of this strategy under various pH levels (10.5-12.5) and exposure time (0.5-6.0 h) in controlling sulfide and methane production was evaluated in laboratory scale anaerobic sewer reactors and then in a real sewer system. Laboratory studies showed that the sulfide production rate of the laboratory sewer biofilm was reduced by 70-90% upon the completion of the pH shock, while the methane production rate decreased by 95-100%. It took approximately one week for the sulfate-reducing activity to recover to normal levels. In comparison, the methanogenic activities recovered to only about 10% in 4 weeks. The slow recovery is explained by the substantially loss of cell viability upon pH shocks, which recovered slowly after the shocks. Laboratory studies further revealed that a pH level of 10.5 for 1-2 h represent cost-effective conditions for the pH shock treatment. However, field trials showed a higher pH (11.5) and larger dosing times are needed due to the pH decreases along the sewer line and at the two ends of the caustic-receiving wastewater slugs due to dilution. To have effective sulfide and methane control, it is important to ensure effective conditions (pH > 10.5 and duration >1-2 h) for the entire sewer line. Copyright © 2013 Elsevier Ltd. All rights reserved.
Hydrocarbons and heavy metals in the different sewer deposits in the 'Le Marais' catchment (Paris, France): stocks, distributions and origins.

PubMed

Rocher, Vincent; Azimi, Sam; Moilleron, Régis; Chebbo, Ghassan

2004-05-05

The knowledge of the pollution stored in combined sewers is of prime importance in terms of management of wet weather flow pollution since sewer deposits play a significant role as source of pollution in combined sewer overflows. This work, which focused on the hydrocarbon (aliphatic and aromatic hydrocarbons) and metallic (Fe, Zn, Pb, Cu and Cd) pollution fixed to the different kinds of sewer deposits (gross bed sediment [GBS], organic layer [OL] and biofilm), was performed in order to provide a complete overview of the contaminant storage in the 'Le Marais' combined sewer (Central Paris, France). Firstly, our results have shown that, for all kinds of pollutants, a major part was stored in the GBS (87 to 98%), a lesser part in the OL (2 to 13%) and an insignificant part in the biofilm (<1%). These results demonstrated that the potential contribution of biofilm to wet weather pollution was negligible compared to the OL one. Secondly, the investigation of hydrocarbon fingerprints in each deposit has provided relevant information about contamination origins: (1) aliphatic hydrocarbon distributions were indicative of petroleum input in the GBS and reflected a mixture of biogenic and petroleum inputs in the OL and biofilm, (2) aromatic hydrocarbon distributions suggested an important pyrolytic contamination in all the deposits. Finally, the study of pollutant fingerprints in the different deposits and in the suspended solids going through the collector has shown that: (1) the suspended solids were the major component of OL and biofilm while urban runoff seemed to be the main transport mechanism introducing pollutants in the GBS and (2) the residence times in sewer of OL and biofilm were quite short compared to those for GBS.
Web Based Decision Support Tools for Selection of Condition ...

EPA Pesticide Factsheets

Abstract: It has been observed that the majority of older sewer laterals made of concrete or terracotta pipe are deteriorating rapidly. Wastewater agencies, typically responsible for maintaining the portion of the sewer lateral located in the public right-of-way, and property owners, typically responsible for the portion of the lateral located within the private property,face the dilemma of whether to replace or rehabilitate deteriorated laterals at significant expense. Deferment of needed rehabilitation translates to increase in the wastewater agency annual operation and maintenance budget and increased risk to the property owner. Sewer lateral deterioration leads to pipe collapse and costly sewer backup. Increase in transmission and treatment costs due to inflow and infiltration (I/I) into the public sewer system is inevitably borne by the ratepayer. [NOTE: The link below connects to a WERF site where the Final Report can be downloaded for free, after registering at the WERF site. For some projects the Executive Summary is available and can be downloaded for free without registering on the WERF site.] A new web portal has been developed that provides wastewater agencies and property owners with up to date information on sewer lateral inspection techniques, repair and rehabilitation methods, as well as relevant legal and financial issues. The site also offers a discussion forum for sharing knowledge and experiences on this topic. The portal is hosted on
The distribution dynamics and desorption behaviour of mobile pharmaceuticals and caffeine to combined sewer sediments.

PubMed

Hajj-Mohamad, M; Darwano, H; Duy, S Vo; Sauvé, S; Prévost, M; Arp, H P H; Dorner, S

2017-01-01

Pharmaceuticals are discharged to the environment from wastewater resource recovery facilities, sewer overflows, and illicit sewer connections. To understand the fate of pharmaceuticals, there is a need to better understand their sorption dynamics to suspended sediments (SS) and settled sediments (StS) in sewer systems. In this study, such sorption dynamics to both SS and StS were assessed using a batch equilibrium method under both static and dynamic conditions. Experiments were performed with natively occurring and artificially modified concentrations of sewer pharmaceuticals (acetaminophen, theophylline, carbamazepine, and a metabolite of carbamazepine) and caffeine. Differences in apparent distribution coefficients, K d,app , between SS and StS were related to differences in their organic carbon (OC) content, and the practice of artificially modifying the concentration. K d,app values of modified contaminant concentrations and high OC sediments were substantially higher. Pseudo-second order desorption rates for these mobile compounds were also quantified. Successive flushing events to simulate the addition of stormwater to sewer networks revealed that aqueous concentrations would not necessarily decrease, because the added water will rapidly return to equilibrium concentrations with the sediments. Sorption and desorption kinetics must be considered in addition to dilution, to avoid underestimating the influence of dilution on concentrations of pharmaceuticals discharged to the environment. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
Variability estimation of urban wastewater biodegradable fractions by respirometry.

PubMed

Lagarde, Fabienne; Tusseau-Vuillemin, Marie-Hélène; Lessard, Paul; Héduit, Alain; Dutrop, François; Mouchel, Jean-Marie

2005-11-01

This paper presents a methodology for assessing the variability of biodegradable chemical oxygen demand (COD) fractions in urban wastewaters. Thirteen raw wastewater samples from combined and separate sewers feeding the same plant were characterised, and two optimisation procedures were applied in order to evaluate the variability in biodegradable fractions and related kinetic parameters. Through an overall optimisation on all the samples, a unique kinetic parameter set was obtained with a three-substrate model including an adsorption stage. This method required powerful numerical treatment, but improved the identifiability problem compared to the usual sample-to-sample optimisation. The results showed that the fractionation of samples collected in the combined sewer was much more variable (standard deviation of 70% of the mean values) than the fractionation of the separate sewer samples, and the slowly biodegradable COD fraction was the most significant fraction (45% of the total COD on average). Because these samples were collected under various rain conditions, the standard deviations obtained here on the combined sewer biodegradable fractions could be used as a first estimation of the variability of this type of sewer system.
Consequential environmental and economic life cycle assessment of green and gray stormwater infrastructures for combined sewer systems.

PubMed

Wang, Ranran; Eckelman, Matthew J; Zimmerman, Julie B

2013-10-01

A consequential life cycle assessment (LCA) is conducted to evaluate the trade-offs between water quality improvements and the incremental climate, resource, and economic costs of implementing green (bioretention basin, green roof, and permeable pavement) versus gray (municipal separate stormwater sewer systems, MS4) alternatives of stormwater infrastructure expansions against a baseline combined sewer system with combined sewer overflows in a typical Northeast US watershed for typical, dry, and wet years. Results show that bioretention basins can achieve water quality improvement goals (e.g., mitigating freshwater eutrophication) for the least climate and economic costs of 61 kg CO2 eq. and $98 per kg P eq. reduction, respectively. MS4 demonstrates the minimum life cycle fossil energy use of 42 kg oil eq. per kg P eq. reduction. When integrated with the expansion in stormwater infrastructure, implementation of advanced wastewater treatment processes can further reduce the impact of stormwater runoff on aquatic environment at a minimal environmental cost (77 kg CO2 eq. per kg P eq. reduction), which provides support and valuable insights for the further development of integrated management of stormwater and wastewater. The consideration of critical model parameters (i.e., precipitation intensity, land imperviousness, and infrastructure life expectancy) highlighted the importance and implications of varying local conditions and infrastructure characteristics on the costs and benefits of stormwater management. Of particular note is that the impact of MS4 on the local aquatic environment is highly dependent on local runoff quality indicating that a combined system of green infrastructure prior to MS4 potentially provides a more cost-effective improvement to local water quality.
Greenville, Mississippi Clean Water Settlement

EPA Pesticide Factsheets

The City of Greenville, MS (City) owns and operates the Greenville Wastewater Treatment Facility (WWTP), approximately 200 miles of sanitary sewer lines, and 100 sanitary sewer pump stations and associated appurtenances.
Consent Decree for Greenville, Mississippi

EPA Pesticide Factsheets

The City of Greenville, MS (City) owns and operates the Greenville Wastewater Treatment Facility (WWTP), approximately 200 miles of sanitary sewer lines, and 100 sanitary sewer pump stations and associated appurtenances.
Hydrologic effects from urbanization of forested watersheds in the northeast

Treesearch

Howard W. Lull; William E. Sopper; William E. Sopper

1969-01-01

Urbanization, particularly in the crowded Northeast, has created a new environment. Asphalt and concrete have replaced hundreds of square miles of soil, buildings have replaced trees on much of the land, and sewers have replaced streambeds in many areas. As a result, the hydrology of this land is changing rapidly. To determine the effects of this expanding urbanization...
Process Design Manual: Wastewater Treatment Facilities for Sewered Small Communities.

ERIC Educational Resources Information Center

Leffel, R. E.; And Others

This manual attempts to describe new treatment methods, and discuss the application of new techniques for more effectively removing a broad spectrum of contaminants from wastewater. Topics covered include: fundamental design considerations, flow equalization, headworks components, clarification of raw wastewater, activated sludge, package plants,…
Finding of No Significant Impact: Proposed Bank Stabilization Tennessee River River Mile 466.2 - 466.5, Hamilton County, Tennessee

DTIC Science & Technology

2013-05-02

Bank erosion is endangering approximately 1,100 feet of a 42-inch concrete gravity sanitary main, two manholes, and a 30-inch iron sanitary sewer...stabilizing the bank. Kingfisher nests are excavated burrows with bare soil along stream banks (USACE, 2009). “Banks with a high content of clay , gravel, or...34’ g -- - -- - - ---- --- -------- 1 LEGEND ESTIMATED 42’’ GRAVITY SEWER LINE ESTIMATED 30’’ FORCE MAIN ® SANITARY SEWER MANHOLE • AUTO
2. ENVIRONMENT, FROM EAST, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. ENVIRONMENT, FROM EAST, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON STREET OVER HARRIS CREEK SEWER - Boston Street Bridge, Spanning Harris Creek Sewer at Boston Street, Baltimore, Independent City, MD
Analysis of time series of Cs-137 concentration in sewage sludge at Fukushima City

NASA Astrophysics Data System (ADS)

Fischer, Helmut W.; Mack, Majvor; Shikano, Yudai; Yokoo, Yoshiyuki

2015-04-01

Daily routine radioisotope measurements of sewage sludge at the sewage plant of Fukushima City starting in 2011 have provided a detailed data set for the isotopes Cs-137, Cs-134 and I-131. The long-term trend for the Cs isotopes is comparable to data sets from Central Europe caused by the Chernobyl emissions in 1986 - the average Cs-137 concentration decreases faster in the first year (T1/2 < 1 yr) and slower in later years (T1/2 > 1 yr). Absolute values at Fukushima City are comparably low (mostly below 1 kBq/kg dry mass), due to the existence of separate wastewater and rainwater sewer systems, with only a small portion of rainwater and erosion products reaching the purification plant. Cs-134 data decay faster due to the shorter radioactive half-life. I-131 appears even years after the NPP releases and is assumed to originate from the common medical usage of the isotope for thyroid treatment. Short-term Cs data show a clear dependence on rainfall: each significant rainfall event causes a concentration increase in sludge of up to a factor of ten. Therefore the time series exhibits high short-term variability. Here we attempt to numerically analyse the detailed Cs-137 data set, using two separate approaches: The first method tries to connect parameters like the local surface deposition density, surface types (sealed/unsealed), rainfall statistics, rainfall-induced erosion rate, leakage rate from rainwater to wastewater sewer, transport time in the sewer and residence time in the purification plant for a basically physical approach. As not all parameters are known, values have to be assumed or can be extracted in the course of the fitting process. The second approach is purely heuristic, based on a water surface runoff and transport model. Whilst there is no ad-hoc physical meaning in the extracted parameters, they can possibly be interpreted as such when compared with physical modeling results. The combination of both methods is expected to give a deeper insight into the transport dynamics of radioisotopes in contaminated areas, helping to identify important sources and sinks and to predict long-term behaviour.

Status of Civil Judicial Consent Decrees Addressing Combined Sewer Systems (CSOs)

EPA Pesticide Factsheets

Tracking table of civil consent decrees for combined sewer systems (CSOs). This supports the National Enforcement Initiative (NEI) for Keeping Raw Sewage and Contaminated Stormwater Out of Our Nation's Waters.
Moving towards Total Water Management

EPA Science Inventory

The presentation will discuss the following topics: Stormwater Best Management Practice (BMP) Placement (SUSTAIN); Sanitary Sewer Overflow Toolbox (SSOAP); BMP and Low Impact Development (LID) Performance; Green/Grey Infrastructure for Stormwater; Combined Sewers and Reuse; Infra...
Effect of flow rate on growth and oxygen consumption of biofilm in gravity sewer.

PubMed

Xu, Jingwei; Li, Muzhi; He, Qiang; Sun, Xingfu; Zhou, Xiangren; Su, Zhenping; Ai, Hainan

2017-01-01

The function of sewer as reactors must rely on the biofilm in it. In this paper, the formation, structure, oxygen transfer, and activity of the biofilm under different hydraulic conditions were studied by the microelectrode technology, oxygen uptake rate (OUR) technology, and 454 high-throughput pyrosequencing technology. Results showed that when the wall-shear stresses were 1.12, 1.29, and 1.45 Pa, the porosity of the steady-state biofilm were 69.1, 64.4, and 55.1 %, respectively. The maximum values of OUR were 0.033, 0.027, and 0.022 mg/(L*s), respectively, and the COD removal efficiency in the sewers reached 40, 35, and 32 %, respectively. The research findings had an important significance on how to improve the treatment efficiency of the sewers. Fig. a Graphical Abstract.
A risk-based approach to sanitary sewer pipe asset management.

PubMed

Baah, Kelly; Dubey, Brajesh; Harvey, Richard; McBean, Edward

2015-02-01

Wastewater collection systems are an important component of proper management of wastewater to prevent environmental and human health implications from mismanagement of anthropogenic waste. Due to aging and inadequate asset management practices, the wastewater collection assets of many cities around the globe are in a state of rapid decline and in need of urgent attention. Risk management is a tool which can help prioritize resources to better manage and rehabilitate wastewater collection systems. In this study, a risk matrix and a weighted sum multi-criteria decision-matrix are used to assess the consequence and risk of sewer pipe failure for a mid-sized city, using ArcGIS. The methodology shows that six percent of the uninspected sewer pipe assets of the case study have a high consequence of failure while four percent of the assets have a high risk of failure and hence provide priorities for inspection. A map incorporating risk of sewer pipe failure and consequence is developed to facilitate future planning, rehabilitation and maintenance programs. The consequence of failure assessment also includes a novel failure impact factor which captures the effect of structurally defective stormwater pipes on the failure assessment. The methodology recommended in this study can serve as a basis for future planning and decision making and has the potential to be universally applied by municipal sewer pipe asset managers globally to effectively manage the sanitary sewer pipe infrastructure within their jurisdiction. Copyright © 2014 Elsevier B.V. All rights reserved.
7 CFR 1980.451 - Filing and processing applications.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... (k) Certificate of need. If the loan request is for health care facilities (e.g., hospitals or... schools, water, sewer and health care services, and if so, the community's plan for providing such... Certificate of Need (Health Care Facilities) 3 Clean Air and Water Pollution Control Act Requirements...
7 CFR 1980.451 - Filing and processing applications.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of the subpart. (k) Certificate of need. If the loan request is for health care facilities (e.g... schools, water, sewer and health care services, and if so, the community's plan for providing such... Certificate of Need (Health Care Facilities) 3 Clean Air and Water Pollution Control Act Requirements...
7 CFR 1980.451 - Filing and processing applications.

Code of Federal Regulations, 2014 CFR

2014-01-01

... of the subpart. (k) Certificate of need. If the loan request is for health care facilities (e.g... schools, water, sewer and health care services, and if so, the community's plan for providing such... Certificate of Need (Health Care Facilities) 3 Clean Air and Water Pollution Control Act Requirements...
7 CFR 1980.451 - Filing and processing applications.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of the subpart. (k) Certificate of need. If the loan request is for health care facilities (e.g... schools, water, sewer and health care services, and if so, the community's plan for providing such... Certificate of Need (Health Care Facilities) 3 Clean Air and Water Pollution Control Act Requirements...
Student Research in the Year of the Coast.

ERIC Educational Resources Information Center

Kane, Julian; And Others

1980-01-01

Described is independent study research at Garden City High School (Garden City, NY) involving ten students studying seasonal beach erosion, salt marsh preservation, sludge leachate hazards in bays, and sewer outfall effects on barrier bays. Outcomes include better understanding of the scientific process and careful, accurate research. (Author/DS)
Total and settling velocity-fractionated pollution potential of sewer sediments in Jiaxing, China.

PubMed

Zhou, Yongchao; Zhang, Ping; Zhang, Yiping; Li, Jin; Zhang, Tuqiao; Yu, Tingchao

2017-10-01

Sewer sediments and their associated contaminant released along with wet-weather discharges pose potential pollution risks to environment. This paper presents total characteristics of sediments collected from Jiaxing, China. Size distribution and concentrations of volatile solids (VS) and four metals (Pb, Cu, Zn, Cr) of sediment samples from seven land use categories were analyzed. Then, the sediment samples were graded five fractions according to its settling velocity through the custom-built settling velocity-grading device. Sediment mass and pollution load distribution based on settling velocity were also assessed. The results show that there are relatively high level of heavy metal load in the sediment of separated storm drainage systems in Jiaxing, especially for the catchment of residential area (RA), road of developed area (RDA), and industrial area (IA). Although grain size follows a trend of increasing along with settling velocity, the methods of settling velocity grading are meaningful for stormwater treatment facilities with precipitation. For all land use categories, the pollution concentrations of the three lower settling velocity-fractionated sediment are relatively consistent and higher than others. Combined with mass distribution, the pollution percentage of fraction with different velocities for seven land use categories were also evaluated. Based on it, the statistical conclusion of design target settling velocity to different pollution load removal rates are drawn, which is helpful to guide design of on-site precipitation separation facilities.
Physical disintegration of toilet papers in wastewater systems: experimental analysis and mathematical modeling.

PubMed

Eren, Beytullah; Karadagli, Fatih

2012-03-06

Physical disintegration of representative toilet papers was investigated in this study to assess their disintegration potential in sewer systems. Characterization of toilet papers from different parts of the world indicated two main categories as premium and average quality. Physical disintegration experiments were conducted with representative products from each category according to standard protocols with improvements. The experimental results were simulated by mathematical model to estimate best-fit values of disintegration rate coefficients and fractional distribution ratios. Our results from mathematical modeling and experimental work show that premium products release more amounts of small fibers and disintegrate more slowly than average ones. Comparison of the toilet papers with the tampon applicators studied previously indicates that premium quality toilet papers present significant potential to persist in sewer pipes. Comparison of turbulence level in our experimental setup with those of partial flow conditions in sewer pipes indicates that drains and small sewer pipes are critical sections where disintegration of toilet papers will be limited. For improvement, requirements for minimum pipe slopes may be increased to sustain transport and disintegration of flushable products in small pipes. In parallel, toilet papers can be improved to disintegrate rapidly in sewer systems, while they meet consumer expectations.
Research of trace metals as markers of entry pathways in combined sewers.

PubMed

Gounou, C; Varrault, G; Amedzro, K; Gasperi, J; Moilleron, R; Garnaud, S; Chebbo, G

2011-01-01

Combined sewers receive high toxic trace metal loads emitted by various sources, such as traffic, industry, urban heating and building materials. During heavy rain events, Combined Sewer Overflows (CSO) can occur and, if so, are discharged directly into the aquatic system and therefore could have an acute impact on receiving waters. In this study, the concentrations of 18 metals have been measured in 89 samples drawn from the three pollutant Entry Pathways in Combined Sewers (EPCS): i) roof runoff, ii) street runoff, and iii) industrial and domestic effluents and also drawn from sewer deposits (SD). The aim of this research is to identify metallic markers for each EPCS; the data matrix was submitted to principal component analysis in order to determine metallic markers for the three EPCS and SD. This study highlights the fact that metallic content variability across samples from different EPCS and SD exceeds the spatio-temporal variability of samples from the same EPCS. In the catchment studied here, the most valuable EPCS and SD markers are lead, sodium, boron, antimony and zinc; these markers could be used in future studies to identify the contributions of each EPCS to CSO metallic loads.
Design and performance evaluation of a simplified dynamic model for combined sewer overflows in pumped sewer systems

NASA Astrophysics Data System (ADS)

van Daal-Rombouts, Petra; Sun, Siao; Langeveld, Jeroen; Bertrand-Krajewski, Jean-Luc; Clemens, François

2016-07-01

Optimisation or real time control (RTC) studies in wastewater systems increasingly require rapid simulations of sewer systems in extensive catchments. To reduce the simulation time calibrated simplified models are applied, with the performance generally based on the goodness of fit of the calibration. In this research the performance of three simplified and a full hydrodynamic (FH) model for two catchments are compared based on the correct determination of CSO event occurrences and of the total discharged volumes to the surface water. Simplified model M1 consists of a rainfall runoff outflow (RRO) model only. M2 combines the RRO model with a static reservoir model for the sewer behaviour. M3 comprises the RRO model and a dynamic reservoir model. The dynamic reservoir characteristics were derived from FH model simulations. It was found that M2 and M3 are able to describe the sewer behaviour of the catchments, contrary to M1. The preferred model structure depends on the quality of the information (geometrical database and monitoring data) available for the design and calibration of the model. Finally, calibrated simplified models are shown to be preferable to uncalibrated FH models when performing optimisation or RTC studies.
Bayesian analysis for erosion modelling of sediments in combined sewer systems.

PubMed

Kanso, A; Chebbo, G; Tassin, B

2005-01-01

Previous research has confirmed that the sediments at the bed of combined sewer systems are the main source of particulate and organic pollution during rain events contributing to combined sewer overflows. However, existing urban stormwater models utilize inappropriate sediment transport formulas initially developed from alluvial hydrodynamics. Recently, a model has been formulated and profoundly assessed based on laboratory experiments to simulate the erosion of sediments in sewer pipes taking into account the increase in strength with depth in the weak layer of deposits. In order to objectively evaluate this model, this paper presents a Bayesian analysis of the model using field data collected in sewer pipes in Paris under known hydraulic conditions. The test has been performed using a MCMC sampling method for calibration and uncertainty assessment. Results demonstrate the capacity of the model to reproduce erosion as a direct response to the increase in bed shear stress. This is due to the model description of the erosional strength in the deposits and to the shape of the measured bed shear stress. However, large uncertainties in some of the model parameters suggest that the model could be over-parameterised and necessitates a large amount of informative data for its calibration.
Advanced Concepts Research Initiative

EPA Science Inventory

This initiative is investigating various approaches to controlling and treating wet-weather flow (WWF) discharges in the urban watershed. WWF, including combined sewer overflow (CSO), sanitary sewer overflow (SSO) and stormwater discharges are leading causes of receiving water q...
Pressurized storm sewer simulation : model enhancement.

DOT National Transportation Integrated Search

1991-01-01

A modified Pressurized Flow Simulation Model, PFSM, was developed and attached to the Federal Highway Administration, FHWA, Pool Funded PFP-HYDRA Package. Four hydrograph options are available for simulating inflow to a sewer system under surcharge o...
A Screening Assessment of the Potential Impacts of Climate ...

EPA Pesticide Factsheets

EPA announced the availability of the report, A Screening Assessment of the Potential Impacts of Climate Change on Combined Sewer Overflow (CSO) Mitigation in the Great Lakes and New England Regions. This report is a screening-level assessment of the potential implications climate change has had on combined sewer overflow (CSO) mitigation in the Great Lakes and New England Regions. This report describes the potential scope and magnitude of climate change impacts on combined sewer overflow (CSOs) mitigation efforts in the Great Lakes Region and New England Region.
Efficient Probabilistic Forecasting for High-Resolution Models through Clustered-State Data Assimilation

NASA Astrophysics Data System (ADS)

Hamidi, A.; Grossberg, M.; Khanbilvardi, R.

2016-12-01

Flood response in an urban area is the product of interactions of spatially and temporally varying rainfall and infrastructures. In urban areas, however, the complex sub-surface networks of tunnels, waste and storm water drainage systems are often inaccessible, pose challenges for modeling and prediction of the drainage infrastructure performance. The increased availability of open data in cities is an emerging information asset for a better understanding of the dynamics of urban water drainage infrastructure. This includes crowd sourced data and community reporting. A well-known source of this type of data is the non-emergency hotline "311" which is available in many US cities, and may contain information pertaining to the performance of physical facilities, condition of the environment, or residents' experience, comfort and well-being. In this study, seven years of New York City 311 (NYC311) call during 2010-2016 is employed, as an alternative approach for identifying the areas of the city most prone to sewer back up flooding. These zones are compared with the hydrologic analysis of runoff flooding zones to provide a predictive model for the City. The proposed methodology is an example of urban system phenomenology using crowd sourced, open data. A novel algorithm for calculating the spatial distribution of flooding complaints across NYC's five boroughs is presented in this study. In this approach, the features that represent reporting bias are separated from those that relate to actual infrastructure system performance. The sewer backup results are assessed with the spatial distribution of runoff in NYC during 2010-2016. With advances in radar technologies, a high spatial-temporal resolution data set for precipitation is available for most of the United States that can be implemented in hydrologic analysis of dense urban environments. High resolution gridded Stage IV radar rainfall data along with the high resolution spatially distributed land cover data are employed to investigate the urban pluvial flooding. The monthly results of excess runoff are compared with the sewer backup in NYC to build a predictive model of flood zones according to the 311 phone calls.
Evaluation of Urban Drainage Infrastructure: New York City Case Study

NASA Astrophysics Data System (ADS)

Hamidi, A.; Grossberg, M.; Khanbilvardi, R.

2017-12-01

Flood response in an urban area is the product of interactions of spatially and temporally varying rainfall and infrastructures. In urban areas, however, the complex sub-surface networks of tunnels, waste and storm water drainage systems are often inaccessible, pose challenges for modeling and prediction of the drainage infrastructure performance. The increased availability of open data in cities is an emerging information asset for a better understanding of the dynamics of urban water drainage infrastructure. This includes crowd sourced data and community reporting. A well-known source of this type of data is the non-emergency hotline "311" which is available in many US cities, and may contain information pertaining to the performance of physical facilities, condition of the environment, or residents' experience, comfort and well-being. In this study, seven years of New York City 311 (NYC311) call during 2010-2016 is employed, as an alternative approach for identifying the areas of the city most prone to sewer back up flooding. These zones are compared with the hydrologic analysis of runoff flooding zones to provide a predictive model for the City. The proposed methodology is an example of urban system phenomenology using crowd sourced, open data. A novel algorithm for calculating the spatial distribution of flooding complaints across NYC's five boroughs is presented in this study. In this approach, the features that represent reporting bias are separated from those that relate to actual infrastructure system performance. The sewer backup results are assessed with the spatial distribution of runoff in NYC during 2010-2016. With advances in radar technologies, a high spatial-temporal resolution data set for precipitation is available for most of the United States that can be implemented in hydrologic analysis of dense urban environments. High resolution gridded Stage IV radar rainfall data along with the high resolution spatially distributed land cover data are employed to investigate the urban pluvial flooding. The monthly results of excess runoff are compared with the sewer backup in NYC to build a predictive model of flood zones according to the 311 phone calls.
Feasibility of sulfide control in sewers by reuse of iron rich drinking water treatment sludge.

PubMed

Sun, Jing; Pikaar, Ilje; Sharma, Keshab Raj; Keller, Jürg; Yuan, Zhiguo

2015-03-15

Dosage of iron salt is the most commonly used method for sulfide control in sewer networks but incurs high chemical costs. In this study, we experimentally investigate the feasibility of using iron rich drinking water treatment sludge for sulfide control in sewers. A lab-scale rising main sewer biofilm reactor was used. The sulfide concentration in the effluent decreased from 15.5 to 19.8 mgS/L (without dosing) to below 0.7-2.3 mgS/L at a sludge dosing rate achieving an iron to total dissolved inorganic sulfur molar ratio (Fe:S) of 1:1, with further removal of sulfide possible by prolonging the reaction time. In fact, batch tests revealed an Fe consumption to sulfide removal ratio of 0.5 ± 0.02 (mole:mole), suggesting the possible occurrence of other reactions involving the removal of sulfide. Modelling revealed that the reaction between iron in sludge and sulfide has reaction orders of 0.65 ± 0.01 and 0.77 ± 0.02 with respect to the Fe and sulfide concentrations, respectively. The addition of sludge slightly increased the total chemical oxidation demand (tCOD) concentration (by approximately 12%) as expected, but decreased the soluble chemical oxidation demand (sCOD) concentration and methane formation by 7% and 20%, respectively. Some phosphate removal (13%) was also observed at the sludge dosing rate of 1:1 (Fe:S), which is beneficial to nutrient removal from the wastewater. Overall, this study suggests that dosing iron-rich drinking water sludge to sewers could be an effective strategy for sulfide removal in sewer systems, which would also reduce the sludge disposal costs for drinking water treatment works. However, its potential side-effects on sewer sedimentation and on the wastewater treatment plant effluent remain to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Microbial Signature Approach to Identify Fecal Pollution in the Waters Off an Urbanized Coast of Lake Michigan

PubMed Central

Newton, Ryan J.; Bootsma, Melinda J.; Morrison, Hilary G.; Sogin, Mitchell L.

2014-01-01

Urban coasts receive watershed drainage from ecosystems that include highly developed lands with sewer and stormwater infrastructure. In these complex ecosystems, coastal waters are often contaminated with fecal pollution, where multiple delivery mechanisms that often contain multiple fecal sources make it difficult to mitigate the pollution. Here, we exploit bacterial community sequencing of the V6 and V6V4 hypervariable regions of the bacterial 16S rRNA gene to identify bacterial distributions that signal the presence of sewer, fecal, and human fecal pollution. The sequences classified to three sewer infrastructure-associated bacterial genera, Acinetobacter, Arcobacter, and Trichococcus, and five fecal-associated bacterial families, Bacteroidaceae, Porphyromonadaceae, Clostridiaceae, Lachnospiraceae, and Ruminococcaceae, served as signatures of sewer and fecal contamination, respectively. The human fecal signature was determined with the Bayesian source estimation program SourceTracker, which we applied to a set of 40 sewage influent samples collected in Milwaukee, WI, USA to identify operational taxonomic units (≥97 % identity) that were most likely of human fecal origin. During periods of dry weather, the magnitudes of all three signatures were relatively low in Milwaukee's urban rivers and harbor and nearly zero in Lake Michigan. However, the relative contribution of the sewer and fecal signature frequently increased to >2 % of the measured surface water communities following sewer overflows. Also during combined sewer overflows, the ratio of the human fecal pollution signature to the fecal pollution signature in surface waters was generally close to that of sewage, but this ratio decreased dramatically during dry weather and rain events, suggesting that nonhuman fecal pollution was the dominant source during these weather-driven scenarios. The qPCR detection of two human fecal indicators, human Bacteroides and Lachno2, confirmed the urban fecal footprint in this ecosystem extends to at least 8 km offshore. PMID:23475306
Modelling the influence of total suspended solids on E. coli removal in river water.

PubMed

Qian, Jueying; Walters, Evelyn; Rutschmann, Peter; Wagner, Michael; Horn, Harald

2016-01-01

Following sewer overflows, fecal indicator bacteria enter surface waters and may experience different lysis or growth processes. A 1D mathematical model was developed to predict total suspended solids (TSS) and Escherichia coli concentrations based on field measurements in a large-scale flume system simulating a combined sewer overflow. The removal mechanisms of natural inactivation, UV inactivation, and sedimentation were modelled. For the sedimentation process, one, two or three particle size classes were incorporated separately into the model. Moreover, the UV sensitivity coefficient α and natural inactivation coefficient kd were both formulated as functions of TSS concentration. It was observed that the E. coli removal was predicted more accurately by incorporating two particle size classes. However, addition of a third particle size class only improved the model slightly. When α and kd were allowed to vary with the TSS concentration, the model was able to predict E. coli fate and transport at different TSS concentrations accurately and flexibly. A sensitivity analysis revealed that the mechanisms of UV and natural inactivation were more influential at low TSS concentrations, whereas the sedimentation process became more important at elevated TSS concentrations.
SEWER PIPELINE PERFORMANCE INDICATORS

EPA Science Inventory

Wastewater collection systems are an extensive part of the nation's infrastructure. In the United States, approximately 150 million people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately o...
40 CFR 35.2005 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... sludge; aquifer recharge; aquaculture; direct reuse (non-potable); horticulture; revegetation of... design-type projects within the scope of the practice of architecture or professional engineering as... as designed. (10) Collector sewer. The common lateral sewers, within a publicly owned treatment...
40 CFR 35.2005 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... sludge; aquifer recharge; aquaculture; direct reuse (non-potable); horticulture; revegetation of... design-type projects within the scope of the practice of architecture or professional engineering as... as designed. (10) Collector sewer. The common lateral sewers, within a publicly owned treatment...
40 CFR 35.2005 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... sludge; aquifer recharge; aquaculture; direct reuse (non-potable); horticulture; revegetation of... design-type projects within the scope of the practice of architecture or professional engineering as... as designed. (10) Collector sewer. The common lateral sewers, within a publicly owned treatment...
40 CFR 35.2005 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... economic investigations or studies, surveys, designs, plans, working drawings, specifications, procedures... design-type projects within the scope of the practice of architecture or professional engineering as... as designed. (10) Collector sewer. The common lateral sewers, within a publicly owned treatment...
40 CFR 35.2005 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... economic investigations or studies, surveys, designs, plans, working drawings, specifications, procedures... design-type projects within the scope of the practice of architecture or professional engineering as... as designed. (10) Collector sewer. The common lateral sewers, within a publicly owned treatment...
USEPA CAPSTONE REPORT: DISINFECTION

EPA Science Inventory

Wet-weather flow (WWF), including combined-sewer overflow (CSO), sanitary-sewer overflow, and stormwater (SW) is a significant contributor of microbial contamination to surface water and ground water. Contamination with human-origin fecal coliform (FC) is of great concern for san...
VERIFICATION OF HIGH-RATE DISINFECTION TECHNOLOGIES FOR WET-WEATHER FLOWS

EPA Science Inventory

This paper describes the critical components of the USEPA's Environmental Technology Verification Program for two specific technologies categories: ultraviolet disinfection technologies for treating combined sewer overflow (CSO) and sanitary sewer overflow (SSO), and; induction m...
OPTIMIZATION OF COMBINED SEWER OVERFLOW CONTROL SYSTEMS

EPA Science Inventory

The highly variable and intermittent pollutant concentrations and flowrates associated with wet-weather events in combined sewersheds necessitates the use of storage-treatment systems to control pollution.An optimized combined-sewer-overflow (CSO) control system requires a manage...
ESTIMATING URBAN WET-WEATHER POLLUTANT LOADING

EPA Science Inventory

This paper presents procedures for estimating pollutant loads in urban watersheds emanating from wet-weather flow discharge. Equations for pollutant loading estimates will focus on the effects of wastewater characteristics, sewer flow carrying velocity, and sewer-solids depositi...
MANAGEMENT OF COMBINED SEWER OVERFLOW: RESEARCH PROGRAM CAPSTONE

EPA Science Inventory

Combined-sewer overflow (CSO) is a mixture of urban storm drainage, municipal-industrial wastewater, and subterranean infiltration. Untreated discharges of CSOs have caused substantial pollution impacts on the quality of receiving-water bodies. Problem constituents include visi...
MANAGEMENT OF COMBINED SEWER OVERFLOW RESEARCH PROGRAM CAPSTONE

EPA Science Inventory

Combined-sewer overflow (CSO) is a mixture of urban storm drainage, municipal-industrial wastewater, and subterranean infiltration. Untreated discharges of CSOs have caused substantial pollution impacts on the quality of receiving-water bodies. Problem constituents include ...
UV Disinfection of Wastewater and Combined Sewer Overflows.

PubMed

Gibson, John; Drake, Jennifer; Karney, Bryan

2017-01-01

Municipal wastewater contains bacteria, viruses, and other pathogens that adversely affect the environment, human health, and economic activity. One way to mitigate these effects is a final disinfection step using ultraviolet light (UVL). The advantages of UVL disinfection, when compared to the more traditional chlorine, include no chlorinated by-products, no chemical residual, and relatively compact size. The design of most UV reactors is complex. It involves lamp selection, power supply design, optics, and hydraulics. In general, medium pressure lamps are more compact, powerful, and emit over a wider range of light than the more traditional low pressure lamps. Low pressure lamps, however, may be electrically more efficient. In UV disinfection, the fraction of surviving organisms (e.g. E. coli) will decrease exponentially with increasing UV dose. However, the level of disinfection that can be achieved is often limited by particle-associated organisms. Efforts to remove or reduce the effects of wastewater particles will often improve UV disinfection effectiveness. Regrowth, photoreactivation, or dark repair after UV exposure are sometimes cited as disadvantages of UV disinfection. Research is continuing in this area, however there is little evidence that human pathogens can photoreactivate in environmental conditions, at doses used in wastewater treatment. The UV disinfection of combined sewer overflows, a form of wet weather pollution, is challenging and remains largely at the research phase. Pre-treatment of combined sewer overflows (CSOs) with a cationic polymer to induce fast settling, and a low dose of alum to increase UV transmittance, has shown promise at the bench scale.
Integrated modelling for the evaluation of infiltration effects.

PubMed

Schulz, N; Baur, R; Krebs, P

2005-01-01

The objective of the present study is the estimation of the potential benefits of sewer pipe rehabilitation for the performance of the drainage system and the wastewater treatment plant (WWTP) as well as for the receiving water quality. The relation of sewer system status and the infiltration rate is assessed based on statistical analysis of 470 km of CCTV (Closed Circuit Television) inspected sewers of the city of Dresden. The potential reduction of infiltration rates and the consequent performance improvements of the urban wastewater system are simulated as a function of rehabilitation activities in the network. The integrated model is applied to an artificial system with input from a real sewer network. In this paper, the general design of the integrated model and its data requirements are presented. For an exemplary study, the consequences of the simulations are discussed with respect to the prioritisation of rehabilitation activities in the network.
A new database on urban runoff pollution: comparison of separate and combined sewer systems.

PubMed

Brombach, H; Weiss, G; Fuchs, S

2005-01-01

For a long time people have questioned what the "best" sewer system is for limiting the pollution load released into the receiving waters. In this paper the traditional separate and combined sewer systems are compared using a pollution load balance. The investigation is based on measured concentration data for a range of pollutant parameters in the sewer from the new database "ATV-DVWK Datenpool 2001". The approach also accounted for the wastewater treatment plant outflow which contributes to the total pollutant load considerably. In spite of a number of neglected effects, the results show that the separate system is superior to the combined for some parameters only, such as nutrients, whereas for other parameters, e.g. heavy metals and COD, the combined system yields less total loads. Any uncritical preference of the separate system as a particularly advantageous solution is thus questionable. Individual investigations case by case are recommended.
Leveraging Spatial Data to Assess Where Sewers Leak and Impinge on Urban Water Quality

NASA Astrophysics Data System (ADS)

Holden, P. A.; Roehrdanz, P.; Lee, D. G.; Feraud, M.; Maier, M.; Means, J. C.; Snyder, S.

2017-12-01

In the modern urban water environment (UWE), engineered systems provide wastewater collection, treatment, and reuse; stormwater and graywater management; and potable water treatment, distribution and conservation. Underpinning such systems are physical, private and public, infrastructures whose integrities impinge on major goals of protecting groundwater and surface water resources, managing flooding, and securing safe drinking water. Here we study sanitary sewers, i.e. the main pipes in wastewater collection systems that improve public health by reducing pathogen exposure, and that afford reclaiming water for beneficial reuse. We ask: what is the relationship between sanitary sewer integrity and nearby water quality? Research methods include acquiring spatially defined sewer metadata that are analyzed using a published pipe leakage algorithm with variables of age, depth, materials of construction, length, diameter, slope, and nature of overburden. By executing the algorithm within a geographical information system (GIS), coupled with relating leakage probabilities to shallow groundwater table proximities—also digitally assembled, from well depth data—maps of wastewater exfiltration scores were produced for a city. Field sampling shallow groundwater allowed assessing concentrations of wastewater indicator compounds including personal care products and pharmaceuticals (PCPPs), and showing positive relationships between wastewater exfiltration scores and tryptophan-like fluorescence (TLF), reactive nitrogen species, an artificial sweetener acesulfame, and a stable isotope of oxygen (δ18O). The approach is extended to surface waters, where exfiltrating wastewater may transport from leaking sanitary sewers through the unsaturated zone to nearby storm drains or to storm drains that are submerged in contaminated groundwater. Spatially assessing sewer interactions within the UWE, as such, could aid urban infrastructure management and investment.
Modelling the effects of on-site greywater reuse and low flush toilets on municipal sewer systems.

PubMed

Penn, R; Schütze, M; Friedler, E

2013-01-15

On-site greywater reuse (GWR) and installation of water-efficient toilets (WET) reduce urban freshwater demand. Research on GWR and WET has generally overlooked the effects that GWR may have on municipal sewer systems. This paper discusses and quantifies these effects. The effects of GWR and WET, positive and negative, were studied by modelling a representative urban sewer system. GWR scenarios were modelled and analysed using the SIMBA simulation system. The results show that, as expected, the flow, velocity and proportional depth decrease as GWR increases. Nevertheless, the reduction is not evenly distributed throughout the day but mainly occurs during the morning and evening peaks. Examination of the effects of reduced toilet flush volumes revealed that in some of the GWR scenarios flows, velocities and proportional depths in the sewer were reduced, while in other GWR scenarios discharge volumes, velocities and proportional depths did not change. Further, it is indicated that as a result of GWR and installation of WET, sewer blockage rates are not expected to increase significantly. The results support the option to construct new sewer systems with smaller pipe diameters. The analysis shows that as the penetration of GWR systems increase, and with the installation of WET, concentrations of pollutants also increase. In GWR scenarios (when toilet flush volume is not reduced) the increase in pollutant concentrations is lower than the proportional reduction of sewage flow. Moreover, the results show that the spatial distribution of houses reusing GW does not significantly affect the parameters examined. Copyright © 2012 Elsevier Ltd. All rights reserved.
Emerging Contaminants in Wet-Weather Flow: Characterization and Treatability

EPA Science Inventory

An extensive literature review was conducted on the presence and magnitude of emerging contaminants (ECs) in wet-weather flow (WWF) including separate stormwater, combined sewer overflow (CSO), and sanitary sewer overflow (SSO). Although little information exists for stormwater ...

SEWER AND TANK SEDIMENT FLUSHING: CASE STUDIES

EPA Science Inventory

The objective of the report summarized here is to demonstrate that sewer system and storage tank flushing that reduces sediment deposition and accumulation is of prime importance to optimizing performance, maintaining structural integrity, and minimizing pollution of receiving wa...
VERIFICATION OF HIGH-RATE DISINFECTION TECHNOLOGIES FOR WET-WEATHER FLOW APPLICATIONS

EPA Science Inventory

This paper describes the critical components of the USEPA's Environmental Technology Verification Program for two specific technologies categories: ultraviolet disinfection technologies for treating combined sewer overflow (CSO) and sanitary sewer overflow (SSO), and; and mechani...
COLLABORATIVE RESEARCH ON URBAN BEST MANAGEMENT PRACTICES

EPA Science Inventory

Storm driven wet weather flow (WWF) which includes combined sewer and sanitary sewer overflows and stormwater discharges are a leading cause of water-quality impairment. Problem constituents in WWF include pathogens, solids, nutrients, and toxicants. New technologies to control...
3. ENVIRONMENT, FROM WEST, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. ENVIRONMENT, FROM WEST, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON STREET OVER HARRIS CREEK SEWER, WITH PORTION OF AMERICAN CAN COMPANY COMPLEX - Boston Street Bridge, Spanning Harris Creek Sewer at Boston Street, Baltimore, Independent City, MD
OPIMIZATION OF COMBINED SEWER OVERFLOW CONTROL SYSTEMS

EPA Science Inventory

The highly variable and intermittent pollutant concentrations and flowrates associated with wet-weather events in combined sewersheds necessitates the use of storage-treatment systems to control pollution. A strategy should be adopted to develop an optimized combined sewer overfl...
Condition Assessment of Wastewater Collection Systems

EPA Science Inventory

Municipal sanitary sewer collection systems play a critical role in protecting public health in our municipalities. They are designed to convey wastewater from their sources to a wastewater treatment plant (WWTP). Collection systems consist of house service laterals, sewers, pu...
HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

EPA Science Inventory

This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...
Antimicrobial Effects of Free Nitrous Acid on Desulfovibrio vulgaris: Implications for Sulfide-Induced Corrosion of Concrete

PubMed Central

Gao, Shu-Hong; Ho, Jun Yuan; Fan, Lu; Richardson, David J.; Yuan, Zhiguo

2016-01-01

ABSTRACT Hydrogen sulfide produced by sulfate-reducing bacteria (SRB) in sewers causes odor problems and asset deterioration due to the sulfide-induced concrete corrosion. Free nitrous acid (FNA) was recently demonstrated as a promising antimicrobial agent to alleviate hydrogen sulfide production in sewers. However, details of the antimicrobial mechanisms of FNA are largely unknown. Here, we report the multiple-targeted antimicrobial effects of FNA on the SRB Desulfovibrio vulgaris Hildenborough by determining the growth, physiological, and gene expression responses to FNA exposure. The activities of growth, respiration, and ATP generation were inhibited when exposed to FNA. These changes were reflected in the transcript levels detected during exposure. The removal of FNA was evident by nitrite reduction that likely involved nitrite reductase and the poorly characterized hybrid cluster protein, and the genes coding for these proteins were highly expressed. During FNA exposure, lowered ribosome activity and protein production were detected. Additionally, conditions within the cells were more oxidizing, and there was evidence of oxidative stress. Based on an interpretation of the measured responses, we present a model depicting the antimicrobial effects of FNA on D. vulgaris. These findings provide new insight for understanding the responses of D. vulgaris to FNA and will provide a foundation for optimal application of this antimicrobial agent for improved control of sewer corrosion and odor management. IMPORTANCE Hydrogen sulfide produced by SRB in sewers causes odor problems and results in serious deterioration of sewer assets that requires very costly and demanding rehabilitation. Currently, there is successful application of the antimicrobial agent free nitrous acid (FNA), the protonated form of nitrite, for the control of sulfide levels in sewers (G. Jiang et al., Water Res 47:4331–4339, 2013, http://dx.doi.org/10.1016/j.watres.2013.05.024). However, the details of the antimicrobial mechanisms of FNA are largely unknown. In this study, we identified the key responses (decreased anaerobic respiration, reducing FNA, combating oxidative stress, and shutting down protein synthesis) of Desulfovibrio vulgaris Hildenborough, a model sewer corrosion bacterium, to FNA exposure by examining the growth, physiological, and gene expression changes. These findings provide new insight and underpinning knowledge for understanding the responses of D. vulgaris to FNA exposure, thereby benefiting the practical application of FNA for improved control of sewer corrosion and odor. PMID:27371588
Localization of groundwater infiltration in the combined sewers of Brussels by stable isotopes measurements (δ18O, δD) by Cavity Ring Down Spectroscopy.

NASA Astrophysics Data System (ADS)

De Bondt, Kevin; Claeys, Philippe

2014-05-01

In the last 20 years research has been conducted to quantify the infiltration of groundwater into the sewers. This groundwater, called parasitic water, increases the volume of waste-water to be treated and consequently the cost of this treatment. Moreover, in the case of combined sewer systems, the parasitic water also limits the sewer capacity and indirectly increases the risks of combined sewer overflows and floods. The infiltration of groundwater occurs trough cracks, sewer collapses and from direct connections with old springs. Different methods quantify the intrusion of parasitic water. Among these, the use of the stable isotopes of water (δ18O & δD) shows good result in catchments or cities close to Mountainous regions (example from Lyon, Zurich), where isotopic signals vary significantly because of continental and altitude effects. However many cities, such as Brussels, are located in more oceanic settings and theoretically offer less potential for the application of the stable isotopes method. In the case of Brussels, river-water from the Meuse is used to produce domestic-water. The catchment of this river extends into the Ardennes, which are affected by slightly different climatic conditions. δ18O & δD analyzes of groundwater from the main aquifer (Ledo-Paniselian-Brusselian) and domestic-water from the Callois reservoir fed by the Meuse River show sufficient isotopic differences in the south of Brussels, but only during the summer. The discrimination potential is better with δD than with δ18O. The improvement of δD measurements (precision, costs,...) brought by Cavity Ring Down Spectroscopy largely contributes to the potential of using stable isotopes method to trace water in Brussels. The first campaigns in the sewers also show a little enrichment (in heavy isotopes) of the waste-water in comparison with the reservoir waters and tap waters. This increases the potential of the method but constrains the sampling to pure waste-water in sewer segments without infiltration generally localized upstream. Anyway, it is in the localization of parasitic water entrance from upstream to downstream that the stable isotopes method is the most powerful. Other methods (e.g. minimum night flow,...) are available at the treatment plants or at flow measurement stations downstream but will not be able to localize parasitic water intrusion towards old springs.
Model-based screening for critical wet-weather discharges related to micropollutants from urban areas.

PubMed

Mutzner, Lena; Staufer, Philipp; Ort, Christoph

2016-11-01

Wet-weather discharges contribute to anthropogenic micropollutant loads entering the aquatic environment. Thousands of wet-weather discharges exist in Swiss sewer systems, and we do not have the capacity to monitor them all. We consequently propose a model-based approach designed to identify critical discharge points in order to support effective monitoring. We applied a dynamic substance flow model to four substances representing different entry routes: indoor (Triclosan, Mecoprop, Copper) as well as rainfall-mobilized (Glyphosate, Mecoprop, Copper) inputs. The accumulation on different urban land-use surfaces in dry weather and subsequent substance-specific wash-off is taken into account. For evaluation, we use a conservative screening approach to detect critical discharge points. This approach considers only local dilution generated onsite from natural, unpolluted areas, i.e. excluding upstream dilution. Despite our conservative assumptions, we find that the environmental quality standards for Glyphosate and Mecoprop are not exceeded during any 10-min time interval over a representative one-year simulation period for all 2500 Swiss municipalities. In contrast, the environmental quality standard is exceeded during at least 20% of the discharge time at 83% of all modelled discharge points for Copper and at 71% for Triclosan. For Copper, this corresponds to a total median duration of approximately 19 days per year. For Triclosan, discharged only via combined sewer overflows, this means a median duration of approximately 10 days per year. In general, stormwater outlets contribute more to the calculated effect than combined sewer overflows for rainfall-mobilized substances. We further evaluate the Urban Index (A urban,impervious /A natural ) as a proxy for critical discharge points: catchments where Triclosan and Copper exceed the corresponding environmental quality standard often have an Urban Index >0.03. A dynamic substance flow analysis allows us to identify the most critical discharge points to be prioritized for more detailed analyses and monitoring. This forms a basis for the efficient mitigation of pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.
Case Study Application of Determining End of Physical Life Using Survival Analysis (WERF Report INFR2R11b)

EPA Science Inventory

Abstract: This case study application provides discussion on a selected application of advanced concepts, included in the End of Asset Life Reinvestment decision-making process tool, using Milwaukee Metropolitan Sewer District (MMSD) pump and motor data sets. The tool provides s...
A catchment-scale groundwater model including sewer pipe leakage in an urban system

NASA Astrophysics Data System (ADS)

Peche, Aaron; Fuchs, Lothar; Spönemann, Peter; Graf, Thomas; Neuweiler, Insa

2016-04-01

Keywords: pipe leakage, urban hydrogeology, catchment scale, OpenGeoSys, HYSTEM-EXTRAN Wastewater leakage from subsurface sewer pipe defects leads to contamination of the surrounding soil and groundwater (Ellis, 2002; Wolf et al., 2004). Leakage rates at pipe defects have to be known in order to quantify contaminant input. Due to inaccessibility of subsurface pipe defects, direct (in-situ) measurements of leakage rates are tedious and associated with a high degree of uncertainty (Wolf, 2006). Proposed catchment-scale models simplify leakage rates by neglecting unsaturated zone flow or by reducing spatial dimensions (Karpf & Krebs, 2013, Boukhemacha et al., 2015). In the present study, we present a physically based 3-dimensional numerical model incorporating flow in the pipe network, in the saturated zone and in the unsaturated zone to quantify leakage rates on the catchment scale. The model consists of the pipe network flow model HYSTEM-EXTAN (itwh, 2002), which is coupled to the subsurface flow model OpenGeoSys (Kolditz et al., 2012). We also present the newly developed coupling scheme between the two flow models. Leakage functions specific to a pipe defect are derived from simulations of pipe leakage using spatially refined grids around pipe defects. In order to minimize computational effort, these leakage functions are built into the presented numerical model using unrefined grids around pipe defects. The resulting coupled model is capable of efficiently simulating spatially distributed pipe leakage coupled with subsurficial water flow in a 3-dimensional environment. References: Boukhemacha, M. A., Gogu, C. R., Serpescu, I., Gaitanaru, D., & Bica, I. (2015). A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania. Hydrogeology Journal, 23(3), 437-450. doi:10.1007/s10040-014-1220-3. Ellis, J. B., & Revitt, D. M. (2002). Sewer losses and interactions with groundwater quality. Water Science and Technology, 45(3), 195-202. itwh (2002). Modellbeschreibung, Institut für technisch-wissenschaftliche Hydrologie GmbH, Hannover. Karpf, C. & Krebs, P. (2013). Modelling of groundwater infiltration into sewer systems. Urban Water Journal, 10:4, 221-229, DOI: 10.1080/1573062X.2012.724077. Kolditz, O., Bauer, S. et al. (2012). OpenGeoSys: an open source initiative for numerical simulation of thermo-hydro-mechanical/chemical (THM/C) processes in porous media. Env. Earth Sci. 67(2):589-599. Wolf, L., Held, I., Eiswirth, M., & Hötzl, H. (2004). Impact of leaky sewers on groundwater quality. Acta Hydrochimica et Hydrobiologica, 32(4-5), 361-373. doi:10.1002/aheh.200400538. Wolf, L. (2006). Influence of leaky sewer systems on groundwater resources beneath the city of Rastatt, Germany. Dissertation, University of Karlsruhe.
Demonstration of Innovative Sewer System Inspection Technology: SL-RAT

EPA Science Inventory

The overall objective of this EPA-funded study was to demonstrate innovative sewer line assessment technologies that are designed for rapid deployment using portable equipment. This study focused on demonstration of technologies that are suitable for smaller diameter pipes (less ...
FLOCCULATION-FLOTATION AIDS FOR TREATMENT OF COMBINED SEWER OVERFLOWS

EPA Science Inventory

The objectives of this study were to investigate the flocculation/flotation characteristics of combined sewer overflow through laboratory and field testing. The concept involves the introduction of chemicals and buoyant flotation aids into the overflow and the subsequent cofloccu...
REAL TIME CONTROL OF SEWERS: US EPA MANUAL

EPA Science Inventory

The problem of sewage spills and local flooding has traditionally been addressed by large scale capital improvement programs that focus on construction alternatives such as sewer separation or construction of storage facilities. The cost of such projects is often high, especiall...
U.S. EPA CSO CAPSTONE REPORT: CONTROL SYSTEM OPTIMIZATION

EPA Science Inventory

An optimized combined sewer overflow (CSO) requires a storage treatment system because storm flow in the combined sewer system is intermittent and highly variable in both pollutant concentration and flow rate. Storage and treatment alternatives are strongly influenced by input...
SSOAP Toolbox Enhancements and Case Study

EPA Science Inventory

Recognizing the need for tools to support the development of sanitary sewer overflow (SSO) control plans, in October 2009 the U.S. Environmental Protection Agency (EPA) released the first version of the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox. This first ve...
1. ENVIRONMENT, FROM SOUTH, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. ENVIRONMENT, FROM SOUTH, SHOWING BOSTON STREET BRIDGE CARRYING BOSTON STREET OVER HARRIS CREEK SEWER OUTLET AT NORTHWEST BRANCH OF PATAPSCO RIVER (BALTIMORE HARBOR) - Boston Street Bridge, Spanning Harris Creek Sewer at Boston Street, Baltimore, Independent City, MD
OVERVIEW OF EPA'S WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

Surface waters receive three types of urban wet-weather flow discharges: combined-sewer overflow (CSO), stormwater, and sanitary-sewer overflow (SSO); all are principally untreated discharges that occur during storm-flow events. WWFs have proven to generate a substantial amount o...
USING VISUAL PLUMES PREDICTIONS TO MODULATE COMBINED SEWER OVERFLOW (CSO) RATES

EPA Science Inventory

High concentrations of pathogens and toxic residues in creeks and rivers can pose risks to human health and ecological systems. Combined Sewer Overflows (CSOs) discharging into these watercourses often contribute significantly to elevating pollutant concentrations during wet weat...

Notification: Review of Atlanta Combined Sewer Overflow Consent Decree

EPA Pesticide Factsheets

Project #OPE-FY17-0014, March 30, 2017. The EPA OIG plans to begin a review of EPA Region 4’s oversight of the Atlanta combined sewer overflow consent decree. For more information, please click on the link above.
40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2014 CFR

2014-07-01

... FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act... transportation and treatment for each defined source of infiltration/inflow. (b) A report shall summarize the... sewer system to eliminate all defined excessive infiltration/inflow. ...
pH dynamics in sewers and its modeling.

PubMed

Sharma, Keshab; Ganigue, Ramon; Yuan, Zhiguo

2013-10-15

pH variation in sewers has a significant effect on hydrogen sulfide production and emissions, and hence its accurate prediction is critical for the optimization of mitigation strategies. In this study, the nature and dynamics of pH variation in a sewer system is examined. Three sewer systems collecting domestic wastewater were monitored, with pH in all cases showing large diurnal variations. pH in fresh sewage in all three cases had a very similar trend with maximum pH in the range of 8.5-8.7. pH variation in fresh sewage followed the same pattern as the sewage flow rate, suggesting that sewage pH is influenced by household water use. Nitrogen content of the wastewater was found to be the most influential factor causing pH variation in fresh sewage, with the total ammonium concentration variation well correlated with the pH variation. A methodology for predicting pH variation in sewers is developed and calibration protocols proposed. The methodology, which is based on the concept of charge balance, was validated using titration curves and field pH data. Measurement of the total ammonium concentration in fresh sewage was found necessary and adequate for the calibration of the charge balance-based pH model. Copyright © 2013 Elsevier Ltd. All rights reserved.
Palatability and efficacy of bromadiolone rodenticide block bait previously exposed to environmental conditions.

PubMed

Nakagawa, Lia; de Masi, Eduardo; Narciso, Emerson; Neto, Hildebrando Montenegro; Papini, Solange

2015-10-01

In São Paulo city, rodent infestation is considered to be a serious public health problem and is the object of a municipal rodent control programme. One of the most important routine methods involves baiting in sewers, using bromadiolone block bait in a pulsed baiting strategy. It has been observed that, after each pulse, bait is not always consumed, and its appearance is altered, which has led to concerns about efficacy. We assessed whether exposure to sewer conditions influences the palatability and efficacy of rodenticide baits to Norway rats (Rattus norvegicus). Baits containing bromadiolone as active ingredient were placed in sewers, removed after 30 days and offered to rats in a two-choice food trial and a no-choice food trial. The appearance of the rodenticide baits changed after 30 days exposure to sewer conditions, but they continued to be palatable and effective against rats. The level of mortality was considered to be satisfactory, 75% in the two-choice food trial and 100% in the no-choice food trial. Results support the reuse of rodenticide block bait in rodent control. It seems to be justified to continue using/reuse baits even when their appearance has changed after 30 days exposure in sewer systems. © 2014 Society of Chemical Industry.
Trace element carriers in combined sewer during dry and wet weather: an electron microscope investigation.

PubMed

El Samrani, A G; Lartiges, B S; Ghanbaja, J; Yvon, J; Kohler, A

2004-04-01

The nature of trace element carriers contained in sewage and combined sewer overflow (CSO) was investigated by TEM-EDX-Electron diffraction and SEM-EDX. During dry weather, chalcophile elements were found to accumulate in sewer sediments as early diagenetic sulfide phases. The sulfurization of some metal alloys was also evidenced. Other heavy metal carriers detected in sewage include metal alloys, some iron oxihydroxide phases and neoformed phosphate minerals such as anapaite. During rain events, the detailed characterization of individual mineral species allowed to differentiate the contributions from various specific sources. Metal plating particles, barite from automobile brake, or rare earth oxides from catalytic exhaust pipes, originate from road runoff, whereas PbSn alloys and lead carbonates are attributed to zinc-works from roofs and paint from building siding. Soil contribution can be traced by the presence of clay minerals, iron oxihydroxides, zircons and rare earth phosphates. However, the most abundant heavy metal carriers in CSO samples were the sulfide particles eroded from sewer sediments. The evolution of relative abundances of trace element carriers during a single storm event, suggests that the pollution due to the "first flush" effect principally results from the sewer stock of sulfides and previously deposited metal alloys, rather than from urban surface runoff.
Public Infrastructure Disparities and the Microbiological and Chemical Safety of Drinking and Surface Water Supplies in a Community Bordering a Landfill

PubMed Central

Heaney, Christopher D.; Wing, Steve; Wilson, Sacoby M.; Campbell, Robert L.; Caldwell, David; Hopkins, Barbara; O’Shea, Shannon; Yeatts, Karin

2015-01-01

The historically African-American Rogers-Eubanks community straddles unincorporated boundaries of two municipalities in Orange County, North Carolina, and predates a regional landfill sited along its border in 1972. Community members from the Rogers-Eubanks Neighborhood Association (RENA), concerned about deterioration of private wells and septic systems and a lack of public drinking water and sewer services, implemented a community-driven research partnership with university scientists and community-based organizations to investigate water and sewer infrastructure disparities and the safety of drinking and surface water supplies. RENA drafted memoranda of agreement with partners and trained community monitors to collect data (inventory households, map water and sewer infrastructure, administer household water and sewer infrastructure surveys, and collect drinking and surface water samples). Respondents to the surveys reported pervasive signs of well vulnerability (100%) and septic system failure (68%). Each 100-m increase in distance from the landfill was associated with a 600 most probable number/100 mL decrease in enterococci concentrations in surface water (95% confidence interval = −1106, −93). Pervasive private household water and sewer infrastructure failures and poor water quality were identified in this community bordering a regional landfill, providing evidence of a need for improved water and sanitation services. PMID:23858663
Improved sulfide mitigation in sewers through on-line control of ferrous salt dosing.

PubMed

Ganigué, Ramon; Jiang, Guangming; Liu, Yiqi; Sharma, Keshab; Wang, Yue-Cong; Gonzalez, José; Nguyen, Tung; Yuan, Zhiguo

2018-05-15

Water utilities worldwide spend annually billions of dollars to control sulfide-induced corrosion in sewers. Iron salts chemically oxidize and/or precipitate dissolved sulfide in sewage and are especially used in medium- and large-size sewers. Iron salt dosing rates are defined ad hoc, ignoring variation in sewage flows and sulfide levels. This often results in iron overdosing or poor sulfide control. Online dosing control can adjust the chemical dosing rates to current (and future) state of the sewer system, allowing high-precision, stable and cost-effective sulfide control. In this paper, we report a novel and robust online control strategy for the dosing of ferrous salt in sewers. The control considers the fluctuation of sewage flow, pH, sulfide levels and also the perturbation from rainfall. Sulfide production in the pipe is predicted using auto-regressive models (AR) based on current flow measurements, which in turn can be used to determine the dose of ferrous salt required for cost-effective sulfide control. Following comprehensive model-based assesment, the control was successfully validated and its effectiveness demonstrated in a 3-week field trial. The online control algorithm controlled sulfide below the target level (0.5 mg S/L) while reducing chemical dosing up to 30%. Copyright © 2018 Elsevier Ltd. All rights reserved.
Assessment of pollutant load emission from combined sewer overflows based on the online monitoring.

PubMed

Brzezińska, Agnieszka; Zawilski, Marek; Sakson, Grażyna

2016-09-01

Cities equipped with combined sewer systems discharge during wet weather a lot of pollutants into receiving waters by combined storm overflows (CSOs). According to the Polish legislation, CSOs should be activated no more than ten times per year, but in Lodz, most of the 18 existing CSOs operate much more frequently. To assess the pollutant load emitted by one of the existing CSOs, the sensors for measuring the concentration of total suspended solids (SOLITAX sc) and dissolved chemical oxygen demand (UVAS plus) installed in the overflow chamber as well as two flowmeters placed in the outflow sewer were used. In order to check the data from sensors, laboratory tests of combined wastewater quality were conducted simultaneously. For the analysis of the total pollutant load emitted from the overflow, the raw data was denoised using the Savitzky-Golay method. Comparing the load calculated from the analytical results to online smoothed measurements, negligible differences were found, which confirms the usefulness of applying the sensors in the combined sewer system. Online monitoring of the quantity and quality of wastewater emitted by the combined sewer overflows to water receivers, provides a considerable amount of data very useful for combined sewerage upgrading based on computer modelling, and allows for a significant reduction of laboratory analysis.
Energy shortage: a benign crisis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armstrong, E.L.

The energy crisis is real and the days of cheap and plentiful energy are gone, perhaps forever. Resources and technology are available to meet the energy austerity. The good evolving from the energy crisis means conservation in many considerations of city planning such as master planning for transportation, water supply, sewers, and utilities; urban construction; and recreation facilities near subdivisions. Urban and suburban areas are evolving from low density residential communities clustering around a well-defined central city to a collection of regional subcenters around the central-city area, each consisting of malls, high- rise office buildings, industrial areas, and apartment complexesmore » linked by belt highways. (MCW)« less
Human impacts on river water quality- comparative research in the catchment areas of the Tone River and the Mur River-

NASA Astrophysics Data System (ADS)

Kogure, K.

2013-12-01

Human activities in river basin affect river water quality as water discharges into river with pollutant after we use it. By detecting pollutants source, pathway, and influential factor of human activities, it will be possible to consider proper river basin management. In this study, material flow analysis was done first and then nutrient emission modeling by MONERIS was conducted. So as to clarify land use contribution and climate condition, comparison of Japanese and European river basin area has been made. The model MONERIS (MOdelling Nutrient Emissions in RIver Systems; Behrendt et al., 2000) was applied to estimate the nutrient emissions in the Danube river basin by point sources and various diffuse pathways. Work for the Mur River Basin in Austria was already carried out by the Institute of Water Quality, Resources and Waste Management at the Vienna University of Technology. This study treats data collection, modelling for the Tone River in Japan, and comparative analysis for these two river basins. The estimation of the nutrient emissions was carried out for 11 different sub catchment areas covering the Tone River Basin for the time period 2000 to 2006. TN emissions into the Tone river basin were 51 kt/y. 67% was via ground water and dominant for all sub catchments. Urban area was also important emission pathway. Human effect is observed in urban structure and agricultural activity. Water supply and sewer system make urban water cycle with pipeline structure. Excess evapotranspiration in arable land is also influential in water cycle. As share of arable land is 37% and there provides agricultural products, it is thought that N emission from agricultural activity is main pollution source. Assumption case of 10% N surplus was simulated and the result was 99% identical to the actual. Even though N surplus reduction does not show drastic impact on N emission, it is of importance to reduce excess of fertilization and to encourage effective agricultural activity. Population rate of waste water treatment is 67 % in the total catchment area. Assumption case of 100% WWT was simulated and the result suggests that connection to public sewer system with WWTP is effective potential measure. TN emission in the Tone is higher than it in the Mur. Emission per capita is almost same level for both basin areas. Though the personal pollution stresses same as European basin area, the basin has huge population and activities to support their daily life. Agricultural activity and urban structure have great impacts on N emission and on the river water quality. Possible remedy for river pollution is construction of sewer system with waste water treatment. Agricultural activity is potential betterment factor. Comparison of Mur, Tone and assumption cases
Efficiency of blue-green stormwater retrofits for flood mitigation - Conclusions drawn from a case study in Malmö, Sweden.

PubMed

Haghighatafshar, Salar; Nordlöf, Beatrice; Roldin, Maria; Gustafsson, Lars-Göran; la Cour Jansen, Jes; Jönsson, Karin

2018-02-01

Coupled one-dimensional (1D) sewer and two-dimensional (2D) overland flow hydrodynamic models were constructed to evaluate the flood mitigation efficiency of a renowned blue-green stormwater retrofit, i.e. Augustenborg, in Malmö, Sweden. Simulation results showed that the blue-green stormwater systems were effective in controlling local surface flooding in inner-city catchments, having reduced the total flooded surfaces by about 70%. However, basement flooding could still be a potential problem depending on the magnitude of the inflows through combined sewer from upstream areas. Moreover, interactions between blue-green retrofits and the surrounding pipe-system were studied. It was observed that the blue-green retrofits reduced the peak flows by approximately 80% and levelled out the runoff. This is a substantial advantage for downstream pipe-bound catchments, as they do not receive a cloudburst-equivalent runoff from the retrofitted catchment, but a reduced flow corresponding to a much milder rainfall. Blue-green retrofits are more effective if primarily implemented in the upstream areas of a pipe-bound catchment since the resulting reduced runoff and levelled out discharge would benefit the entire network lying downstream. Implementing blue-green retrofits from upstream towards downstream can be considered as a sustainable approach. Copyright © 2017 Elsevier Ltd. All rights reserved.
Utilization of an Airborne Plant Chlorophyll Imaging System for Detection of Septic System Malfunction

NASA Technical Reports Server (NTRS)

Spiering, Bruce A.; Carter, Gregory A.

2001-01-01

Malfunctioning, or leaking, sewer systems increase the supply of water and nutrients to surface vegetation. Excess nutrients and harmful bacteria in the effluent pollute ground water and local water bodies and are dangerous to humans and the aquatic ecosystems. An airborne multispectral plant chlorophyll imaging system (PCIS) was used to identify growth patterns in the vegetation covering onsite and public sewer systems. The objective was to evaluate overall performance of the PCIS as well as to determine the best operational configuration for this application. The imaging system was flown in a light aircraft over selected locations Mobile County, Alabama. Calibration panels were used to help characterize instrument performance. Results demonstrated that the PCIS performed well and was capable of detecting septic leakage patterns from altitudes as high as 915 m. From 915 m, 6 of 18 sites were suspected to have sewage leakage. Subsequent ground inspections confirmed leakage on 3 of the 6 sites. From 610 m, 3 of 8 known leakage sites were detected. Tree cover and shadows near residential structures prevented detection of several known malfunctioning systems. Also some leakages known to occur in clear areas were not detected. False detections occurred in areas characterized by surface water drainage problems or recent excavation.
MANUAL: REAL TIME CONTROL OF COMBINED SEWERS

EPA Science Inventory

Managers, engineers, and operators of combined urban sewer systems are faced with difficult problems related to the operation and maintenance of their facilities. In addition to the issues related to the operation and upkeep of the system, many sewerage agencies are facing increa...
Demonstration of an Innovative Large-Diameter Sewer Rehabilitation Technology in Houston, Texas

EPA Science Inventory

While sewer renewal technologies currently being used for the repair, replacement and/or rehabilitation of deteriorating wastewater collection systems are generally effective, there is still room for improvement of existing technologies and for the development of new technologies...
Colorado River Sewer System Joint Venture to Upgrade Wastewater System

EPA Pesticide Factsheets

SAN FRANCISCO -Today, the Colorado River Sewer System Joint Venture, located in Parker, Ariz. entered into an agreement with the EPA to upgrade their wastewater treatment system to meet stringent water quality standards. The cost of the upgrade is ap
High-Rate Disinfection Techniques for Combined Sewer Overflow (Proceedings Paper)

EPA Science Inventory

This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH ), a...
EXFILTRATION IN SEWER SYSTEMS: IS IT A NATIONAL PROBLEM?

EPA Science Inventory

Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...
US EPA CSO CAPSTONE REPORT: THE CSO PROBLEM

EPA Science Inventory

The history of combined sewer systems (CSS) and combined sewer overflows (CSOs) in the US provides unique insights into the complex challenge faced in reducing and eliminating their adverse environmental effects. The evolution of the "modern" CSS shows how early urban drainag sys...
Incorporating Storm Sewer Exfiltration into SWMM: Proof of Concept

EPA Science Inventory

This study evaluates the peak flow and volume reduction achieved by exfiltration from a perforated storm sewer in an urban catchment. There are three related objectives: [1] quantify peak flow and volume reduction; [2] demonstrate adaptability to climate change; and [3] evaluate ...
EXFILTRATION IN SANITARY SEWER SYSTEMS IN THE U.S.

EPA Science Inventory

Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...

Demonstration of an Innovative Large-Diameter Sewer Rehabilitation Technology in Houston, Texas - slides

EPA Science Inventory

While sewer renewal technologies currently being used for the repair, replacement and/or rehabilitation of deteriorating wastewater collection systems are generally effective, there is still room for improvement of existing technologies and for the development of new technologies...
CHALLENGES OF COMBINED SEWER OVERFLOW DISINFECTION BY ULTRAVIOLET LIGHT IRRADIATION

EPA Science Inventory

This article examines the performance and effectiveness of ultraviolet (UV) light irradiation for disinfection of combined sewer overflow (CSO). Due to the negative impact of conventional water disinfectants on aquatic life, new agents (e.g., UV light) are being investigated for ...
NPDES Permit for Air Force Academy Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042007, the U.S. Air Force Academy is authorized to discharge from all municipal separate storm sewer system outfalls to the receiving waters specified in the permit in El Paso County, Colorado.
EVALUATING INNOVATIVE STORMWATER TREATMENT TECHNOLOGIES UNDER THE ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) PROGRAM

EPA Science Inventory

Assessing, controlling, and treating combined-sewer overflows (CSO), sanitary sewer overflows (SSO), and urban stormwater runoff have become priorities for communities. Improved and cost effective treatment technologies are needed to reduce the adverse impacts that wet weather f...
PERFORMANCE OF OZONE AS A DISINFECTANT FOR COMBINED SEWER OVERFLOW

EPA Science Inventory

Disinfection of combined sewer overflow (CSO) minimizes the amount of disease-causing microorganisms (pathogens) released into receiving waters. Currently, the primary disinfecting agent used in the US for wastewater treatment is chlorine (Cl2); however, Cl2 produces problems in ...
78 FR 18629 - Notice of Lodging of Proposed Partial Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

... sewer system, perform initial work over the next four years to address sewer overflows, develop a..., DC 20044- 7611. Please enclose a check or money order for $84.50 (25 cents per page reproduction cost...
Evaluating Rotavirus and Norovirus transport processes in standardised and natural soil-water columns experiments

NASA Astrophysics Data System (ADS)

Gamazo, Pablo; Schijven, Jack; Victoria, Matias; Alvareda, Elena; López Tort, Fernando; Ramos, Julián; Lizasoain, Andrés; Sapriza, Gonzalo; Castells, Matias; Colina, Rodney

2017-04-01

In Uruguay, as in many developed and developing countries, rotavirus and norovirus are major causes of diarrhea and others symptoms of acute gastroenteritis. In some areas of Uruguay, groundwater is the only source of water for human consumption. In the rural area of the Salto district, virus contamination has been detected in several groundwater wells. Because sewer coverage is low, the most probable sources of contamination are nearby septic systems. This work aims to evaluate the transport of rotavirus and norovirus from clinic samples in two sets of column experiments under saturated conditions: 6.7-cm columns with quartz sand (ionic strength 1mM, pH 7.0) and with sand from the Salto aquifer (Uruguay) (9,2% coarse sand, 47,8% medium sand, 40,5% fine sand, magnesium/calcium bicarbonate water, Ionic strength 15.1 mM, pH 7.2). Both viruses were seeded for 2 pore volumes onto the columns. Samples were collected at the column outlet and viruses were enumerated by Q-PRCR. Breakthrough curves were constructed and fitted to a two-site kinetic attachment/detachment model, including blocking using Hydrus-1D. In the quartz sand column, both rotavirus and norovirus were removed two orders in magnitude. In the Salto sand column, rotavirus was removed 2 log10 as well, but norovirus was removed 4 log10. The fitting of the breakthrough curves indicated that blocking played a role for rotavirus in the Salto sand column. These results are consistent with the field observation where only rotavirus was detected in the Salto aquifer, while similar concentrations in Salto sewer effluent were measured for both viruses. This work, besides reporting actual parameters values for human virus transport modelling, shows the significant differences in transport that human viruses can have in standardised and natural soil-water systems.
Analysis of the influence of rainfall variables on urban effluents concentrations and fluxes in wet weather

NASA Astrophysics Data System (ADS)

Gooré Bi, Eustache; Monette, Frédéric; Gasperi, Johnny

2015-04-01

Urban rainfall runoff has been a topic of increasing importance over the past years, a result of both the increase in impervious land area arising from constant urban growth and the effects of climate change on urban drainage. The main goal of the present study is to assess and analyze the correlations between rainfall variables and common indicators of urban water quality, namely event mean concentrations (EMCs) and event fluxes (EFs), in order to identify and explain the impacts of each of the main rainfall variables on the generation process of urban pollutants during wet periods. To perform this analysis, runoff from eight summer rainfall events that resulted in combined sewer overflow (CSO) was sampled simultaneously from two distinct catchment areas in order to quantify discharges at the respective outfalls. Pearson statistical analysis of total suspended solids (TSS), chemical oxygen demand (COD), carbonaceous biochemical oxygen demand at 5 days (CBOD5), total phosphorus (Ptot) and total kedjal nitrogen (N-TKN) showed significant correlations (ρ = 0.05) between dry antecedent time (DAT) and EMCs on one hand, and between total rainfall (TR) and the volume discharged (VD) during EFs, on the other. These results show that individual rainfall variables strongly affect either EMCs or EFs and are good predictors to consider when selecting variables for statistical modeling of urban runoff quality. The results also show that in a combined sewer network, there is a linear relationship between TSS event fluxes and COD, CBOD5, Ptot, and N-TKN event fluxes; this explains 97% of the variability of these pollutants which adsorb onto TSS during wet weather, which therefore act as tracers. Consequently, the technological solution selected for TSS removal will also lead to a reduction of these pollutants. Given the huge volumes involved, urban runoffs contribute substantially to pollutant levels in receiving water bodies, a situation which, in a climate change context, may get much worse as a result of more frequent, shorter, but more intense rainfall events.
Blue and green infrastructures implementation to solve stormwater management issues in a new urban development project - a modelling approach

NASA Astrophysics Data System (ADS)

Versini, Pierre-Antoine; Tchiguirinskaia, Ioulia; Schertzer, Daniel

2016-04-01

Concentrating buildings and socio-economic activities, urban areas are particularly vulnerable to hydrological risks. Modification in climate may intensify already existing issues concerning stormwater management (due to impervious area) and water supply (due to the increase of the population). In this context, water use efficiency and best water management practices are key-issues in the urban environment already stressed. Blue and green infrastructures are nature-based solutions that provide synergy of the blue and green systems to provide multifunctional solutions and multiple benefits: increased amenity, urban heat island improvement, biodiversity, reduced energy requirements... They are particularly efficient to reduce the potential impact of new and existing developments with respect to stormwater and/or water supply issues. The Multi-Hydro distributed rainfall-runoff model represents an adapted tool to manage the impacts of such infrastructures at the urban basin scale. It is a numerical platform that makes several models interact, each of them representing a specific portion of the water cycle in an urban environment: surface runoff and infiltration depending on a land use classification, sub-surface processes and sewer network drainage. Multi-Hydro is still being developed at the Ecole des Ponts (open access from https://hmco.enpc.fr/Tools-Training/Tools/Multi-Hydro.php) to take into account the wide complexity of urban environments. The latest advancements have made possible the representation of several blue and green infrastructures (green roof, basin, swale). Applied in a new urban development project located in the Paris region, Multi-Hydro has been used to simulate the impact of blue and green infrastructures implementation. It was particularly focused on their ability to fulfil regulation rules established by local stormwater managers in order to connect the parcel to the sewer network. The results show that a combination of several blue and green infrastructures, if they are widely implemented, could represent an efficient tool to ensure regulation rules at the parcel scale.
Comparison of Rotavirus and Norovirus transport in standardised and natural soil-water systems

NASA Astrophysics Data System (ADS)

Gamazo, P. A.; Schijven, J. F.; Victoria, M.; Alvareda, E.; Lopez, F.; Ramos, J.; Lizasoain, A.; Sapriza-Azuri, G.; Castells, M.; Colina, R.

2016-12-01

Rotavirus and Norovirus are waterborne viruses that are major causes of diarrhea and others symptoms of acute gastroenteritis. An important pathway of these viruses is groundwater. In Uruguay, as in many developed and developing countries, there are areas where the only source of water for human consumption is groundwater. In the rural area of the Salto district, groundwater is commonly used without any treatment, as it is traditionally considered as a safe source. However, virus contamination have been detected in several wells in the area. The most probable source of contamination are nearby septic systems, since the sewer coverage is scarce. This work aims to evaluate and compare the virus transport processes for a standardised soil-water systems and for the Salto aquifer system. For this, the transport of Rotavirus and Norovirus from clinic samples was studied in two sets of column experiments: 6.7 cm columns with quartz sand under saturated conditions (ionic strength 1mM, pH 7.0) and with sand from the Salto aquifer (Uruguay) (9,2% coarse sand, 47,8% medium sand, 40,5% fine sand, magnesium/calcium bicarbonate water, Ionic strength 15.1 mM, pH 7.2). Both viruses were seeded for 2 pore volumes on the columns. Samples were collected at the column outlet and viruses were enumerated by Q-PRCR. Breakthrough curves were constructed and fitted to a two-site kinetic attachment/detachment model, including blocking using Hydrus-1D. In the quartz sand column, both Rotavirus and Norovirus were removed two orders in magnitude. In the Salto sand column, Rotavirus was removed 2 log10 as well, but Norovirus was removed 4 log10. The fitting of the breakthrough curves indicated that blocking played a role for Rotavirus in the Salto sand column. These results are consistent with field observation where only Rotavirus was detected in the Salto aquifer, while similar concentrations in Salto sewer effluent was measured for these two viruses. This work, besides reporting actual parameters values for human virus transport modelling, shows the significant differences in transport that human viruses can have in standardised and natural soil-water systems.
Online dissolved methane and total dissolved sulfide measurement in sewers.

PubMed

Liu, Yiwen; Sharma, Keshab R; Fluggen, Markus; O'Halloran, Kelly; Murthy, Sudhir; Yuan, Zhiguo

2015-01-01

Recent studies using short-term manual sampling of sewage followed by off-line laboratory gas chromatography (GC) measurement have shown that a substantial amount of dissolved methane is produced in sewer systems. However, only limited data has been acquired to date due to the low frequency and short span of this method, which cannot capture the dynamic variations of in-sewer dissolved methane concentrations. In this study, a newly developed online measuring device was used to monitor dissolved methane concentrations at the end of a rising main sewer network, over two periods of three weeks each, in summer and early winter, respectively. This device uses an online gas-phase methane sensor to measure methane under equilibrium conditions after being stripped from the sewage. The data are then converted to liquid-phase methane concentrations according to Henry's Law. The detection limit and range are suitable for sewer application and can be adjusted by varying the ratio of liquid-to-gas phase volume settings. The measurement presented good linearity (R² > 0.95) during field application, when compared to off-line measurements. The overall data set showed a wide variation in dissolved methane concentration of 5-15 mg/L in summer and 3.5-12 mg/L in winter, resulting in a significant average daily production of 24.6 and 19.0 kg-CH₄/d, respectively, from the network with a daily average sewage flow of 2840 m³/day. The dissolved methane concentration demonstrated a clear diurnal pattern coinciding with flow and sulfide fluctuation, implying a relationship with the wastewater hydraulic retention time (HRT). The total dissolved sulfide (TDS) concentration in sewers can be determined simultaneously with the same principle.
ULTRAVIOLET LIGHT DISINFECTION OF COMBINED SEWER OVERFLOW (NEW ORLEANS)

EPA Science Inventory

The objective of this state-of-the-art review is to examine the performance and effectiveness of ultraviolet (UV) light disinfection for combined sewer overflow (CSO) applications. Topics presented include the use of UV light as a disinfecting agent, its practical applications, d...
Enforcement to Address Sewer Overflows | Eliminating ...

EPA Pesticide Factsheets

2017-04-10

EPA's compliance goal is to eliminate sanitary sewer overflows (SSOs) from municipal collection systems and to ensure that wastewater is being conveyed to treatment plants in accordance with the requirements of the Clean Water Act. To eliminate SSOs, EPA uses a mix of compliance and enforcement tools.
Multistakeholder Evaluation of Condominial Sewer Services

ERIC Educational Resources Information Center

Nance, Earthea

2005-01-01

A multistakeholder evaluation procedure is presented to address the many challenges in evaluating the performance of condominial sewer projects in Brazil. Condominial sewerage is a promising appropriate technology that is coproduced by users and public agencies, but little is known about project performance. This article shows that…
CHARACTERIZATION OF METALS IN RUNOFF FROM RESIDENTIAL AND HIGHWAY STORM SEWERS

EPA Science Inventory

Stormwater runoff was sampled from six storm sewer outfalls in residential and highway settings in Monmouth County, NJ to determine the colloidal and dissolved metal concentrations. Heavy metals, common pollutants in natural waters and stormwater, are known to associate with par...
ENVIRONMENTAL FOOTPRINT OF PHARMACEUTICALS - THE SIGNIFICANCE OF FACTORS BEYOND DIRECT EXCRETION TO SEWERS

EPA Science Inventory

The combined excretion of active pharmaceutical ingredients (APIs) via urine and feces is considered the primary route by which APIs from human pharmaceuticals enter the environment. Disposal of unwanted, leftover medications by flushing into sewers has been considered a secondar...
EPA Office of Research and Development - I/I Research Information Update

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and is currently one of the top national water program priorities. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox to assist communities in devel...
33 CFR 238.6 - General policy.

Code of Federal Regulations, 2010 CFR

2010-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...
33 CFR 238.6 - General policy.

Code of Federal Regulations, 2012 CFR

2012-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...
33 CFR 238.6 - General policy.

Code of Federal Regulations, 2014 CFR

2014-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...
33 CFR 238.6 - General policy.

Code of Federal Regulations, 2013 CFR

2013-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...
State of Technology Report for Force Main Rehabilitation

EPA Science Inventory

Force mains that carry sewage flows under pressure represent a special set of challenges for sewer rehabilitation. Force mains represent about 7.5% of the wastewater system and they typically use materials that are not commonly used in gravity sewer systems. Ductile iron (DI), ...
LAND USE AND SEASONAL EFFECTS ON URBAN STORMWATER RUNOFF MICROORGANISM CONCENTRATIONS

EPA Science Inventory

Stormwater samples collected from storm sewers draining small municipal separate storm sewer systems shown to be free of cross connections within an urban watershed dominated by a single land use were analyzed for pathogens (Pseudomonas aeruginosa and Staphylococcus aureus) and i...
EFFECTS OF LAND USE AND SEASON ON MICROORGANISM CONCENTRATIONS IN URBAN STORMWATER RUNOFF

EPA Science Inventory

This study investigated differences in pathogen and indicator organism concentrations in stormwater runoff between different urban land uses and seasons. Stormwater samples collected from storm sewers draining small municipal separate storm sewer systems shown to be free of cros...
MODELS TO ESTIMATE VOLATILE ORGANIC HAZARDOUS AIR POLLUTANT EMISSIONS FROM MUNICIPAL SEWER SYSTEMS

EPA Science Inventory

Emissions from municipal sewers are usually omitted from hazardous air pollutant (HAP) emission inventories. This omission may result from a lack of appreciation for the potential emission impact and/or from inadequate emission estimation procedures. This paper presents an analys...
SEMINAR PUBLICATION: NATIONAL CONFERENCE ON SANITARY SEWER OVERFLOWS (SSOS)

EPA Science Inventory

This seminar publication presents selected peer-reviewed papers from the conference. Thousands of municipalities across the nation are serviced by separate sanitary sewer systems. A chronic problem that faces many of these systems is the occurrence of SSOs, caused mainly by the i...
Re-examination of the 1994 and subsequent sewer and culvert installations of various pipe types, sizes and depths.

DOT National Transportation Integrated Search

2014-02-01

In 1994 the Michigan Department of Transportation (MDOT) initiated a sewer and culvert : condition research conducted at various locations throughout Southeast and Southwest : Michigan to review the performance of concrete, plastic and metal pipe tha...
NPDES Permit for Fort Carson Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042001, Fort Carson is authorized to discharge from all municipal separate storm sewer system outfalls to receiving waters which include B-Ditch, Clover Ditch, Infantry Creek, Rock Creek, and others in El Paso County, Colorado.
NPDES Permit for Denver VA Hospital Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042008, the Veterans Administration (Medical Center, Denver Campus) is authorized to discharge from all municipal separate storm sewer system outfalls to the receiving waters specified in the permit in the City of Denver, Colorado.
STREET SURFACE STORAGE FOR CONTROL OF COMBINED SEWER SURCHARGE

EPA Science Inventory

One type of Best Management Practices (BMPs) available is the use of street storage systems to prevent combined sewer surcharging and to mitigate basement flooding. A case study approach, based primarily on two largely implemented street storage systems, will be used to explain ...
A microcomputer model for simulating pressurized flow in a storm sewer system : interim report.

DOT National Transportation Integrated Search

1988-01-01

A study is being conducted on the development of a microcomputer model for simulating storm sewer flow under surcharged or pressurized conditions. Several existing models, including the EPA Storm Water Management Hodel (SYMM) and the Illinois Urban D...
Coordinated management of combined sewer overflows by means of environmental decision support systems.

PubMed

Murla, Damian; Gutierrez, Oriol; Martinez, Montse; Suñer, David; Malgrat, Pere; Poch, Manel

2016-04-15

During heavy rainfall, the capacity of sewer systems and wastewater treatment plants may be surcharged producing uncontrolled wastewater discharges and a depletion of the environmental quality. Therefore there is a need of advanced management tools to tackle with these complex problems. In this paper an environmental decision support system (EDSS), based on the integration of mathematical modeling and knowledge-based systems, has been developed for the coordinated management of urban wastewater systems (UWS) to control and minimize uncontrolled wastewater spills. Effectiveness of the EDSS has been tested in a specially designed virtual UWS, including two sewers systems, two WWTP and one river subjected to typical Mediterranean rain conditions. Results show that sewer systems, retention tanks and wastewater treatment plants improve their performance under wet weather conditions and that EDSS can be very effective tools to improve the management and prevent the system from possible uncontrolled wastewater discharges. Copyright © 2016 Elsevier B.V. All rights reserved.
Sensor Agent Processing Software (SAPS)

DTIC Science & Technology

2004-05-01

buildings, sewers, and tunnels. The time scale governs many aspects of tactical sensing. In high intensity combat situations forces move within...21 Figure 9-2 BAE Systems Sitex00 High Bandwidth...float) Subscribers Subscribers Preprocessor Channel 1 xout[256] Data File in Memory xout[256] S w i t c h High Pass Filter (IIR) xin[256] xout[256
Remaining Sites Verification Package for the 100-F-26:10, 1607-F3 Sanitary Sewer Pipelines (182-F, 183-F, and 151-F Sanitary Sewer Lines), Waste Site Reclassification Form 2007-028

DOE Office of Scientific and Technical Information (OSTI.GOV)

L. M. Dittmer

2007-12-03

The 100-F-26:10 waste site includes sanitary sewer lines that serviced the former 182-F, 183-F, and 151-F Buildings. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Dynamic online sewer modelling in Helsingborg.

PubMed

Hernebring, C; Jönsson, L E; Thorén, U B; Møller, A

2002-01-01

Within the last decade, the sewer system in Helsingborg, Sweden has been rehabilitated in many ways along with the reconstruction of the WWTP Oresundsverket in order to obtain a high degree of nitrogen and phosphorus removal. In that context a holistic view has been applied in order to optimise the corrective measures as seen from the effects in the receiving waters. A sewer catchment model has been used to evaluate several operation strategies and the effect of introducing RTC. Recently, a MOUSE ONLINE system was installed. In this phase the objective is to establish a stable communication with the SCADA system and to generate short-term flow forecasts.
Transient Point Infiltration In The Unsaturated Zone

NASA Astrophysics Data System (ADS)

Buecker-Gittel, M.; Mohrlok, U.

The risk assessment of leaking sewer pipes gets more and more important due to urban groundwater management and environmental as well as health safety. This requires the quantification and balancing of transport and transformation processes based on the water flow in the unsaturated zone. The water flow from a single sewer leakage could be described as a point infiltration with time varying hydraulic conditions externally and internally. External variations are caused by the discharge in the sewer pipe as well as the state of the leakage itself. Internal variations are the results of microbiological clogging effects associated with the transformation processes. Technical as well as small scale laboratory experiments were conducted in order to investigate the water transport from an transient point infiltration. From the technical scale experiment there was evidence that the water flow takes place under transient conditions when sewage infiltrates into an unsaturated soil. Whereas the small scale experiments investigated the hydraulics of the water transport and the associated so- lute and particle transport in unsaturated soils in detail. The small scale experiment was a two-dimensional representation of such a point infiltration source where the distributed water transport could be measured by several tensiometers in the soil as well as by a selective measurement of the discharge at the bottom of the experimental setup. Several series of experiments were conducted varying the boundary and initial con- ditions in order to derive the important parameters controlling the infiltration of pure water from the point source. The results showed that there is a significant difference between the infiltration rate in the point source and the discharge rate at the bottom, that could be explained by storage processes due to an outflow resistance at the bottom. This effect is overlayn by a decreasing water content decreases over time correlated with a decreasing infiltration rate. As expected the initial conditions mainly affects the time scale for the water transport. Additionally, the influence of preferential flow paths on the discharge distribution could be found due to the heterogenieties caused by the filling and compaction process of the sandy soil.
SSOAP - A USEPA TOOLBOX FOR SSO ANALYSIS AND CONTROL PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...
40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...
40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

Some links on this page may take you to non-federal websites. Their policies may differ from this site.