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Sample records for tailings dam failure

  1. Velocity field measurements in tailings dam failure experiments using a combined PIV-PTV approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tailings dams are built to impound mining waste, also called tailings, which consists of a mixture of fine-sized sediments and water contaminated with some hazardous chemicals used for extracting the ore by leaching. Non-Newtonian flow of sediment-water mixture resulting from a failure of tailings d...

  2. Survey of Radionuclide Distributions Resulting from the Church Rock, New Mexico, Uranium Mill Tailings Pond Dam Failure

    SciTech Connect

    Weimer, W. C.; Kinnison, R. R.; Reeves, J. H.

    1981-12-01

    An intensive site survey and on-site analysis program were conducted to evaluate the distribution of four radionucliGes in the general vicinity of Gallup, New Mexico, subsequent to the accidental breach of a uranium mill tailings pond dam and the release of a large quantity of tailings pond materials. The objective of this work was to determine the distribution and concentration levels of {sup 210}Pb, {sup 226}Ra, {sup 230}Th, and {sup 238}U in the arroyo that is immediately adjacent to the uranium tailings pond (pipeline arroyo) and in the Rio Puerco arroyo into which the pipeline arroyo drains. An intensive survey between the United Nuclear Corporation (UNC) Church Rock Mill site and the New Mexico-Arizona state border was performed. Sampling locations were established at approximately 500-ft intervals along the arroyo. During the weeks of September 24 through October 5, 1979, a series of samples was collected from alternate sampling locations along the arroyo. The purpose of this collection of samples and their subsequent analysis was to provide an immediate evaluation of the extent and the levels of radioactive contamination. The data obtained from this extensive survey were then compared to action levels which had been proposed by the Nuclear Regulatory Commission and were adapted by the New Mexico Environmental Improvement Division (NMEID) for {sup 230}Th and {sup 226}Ra concentrations that would require site cleanup. The Pacific Northwest Laboratory/Nuclear Regulatory Commission mobile laboratory van was on-site at the UNC Church Rock Mill from September 22, 1979, through December 13, 1979, and was manned by one or more PNL personnel for all but four weeks of this time period. Approximately 1200 samples associated with the Rio Puerco survey were analyzed 1n the laboratory. An additional 1200 samples related to the Rio Puerco cleanup operations which the United Nuclear Corporation was conducting were analyzed on-site in the mobile laboratory. The purpose of these analyses was to determine the effectiveness of the cleanup operations that were ongoing and to evaluate what additional cleanup would be required. This on-site analysis of radioactive contamination constituted the principal task of this project, with the identification of those portions of the arroyo exceeding the NMEID proposed cleanup criteria being the major output. Additiond1 tasks included an evaluation of the initial soil sampling scheme (letter from T. Wolff [NMEID] to J. Abiss [UNC]. oated September 25, 1979) and the proposed NMEID verification sampling scheme (letter from T. Buhl [NMEID] to H. Miller [NRC]. dated April 23, 1980).

  3. Tailings dam-break flow - Analysis of sediment transport

    NASA Astrophysics Data System (ADS)

    Aleixo, Rui; Altinakar, Mustafa

    2015-04-01

    A common solution to store mining debris is to build tailings dams near the mining site. These dams are usually built with local materials such as mining debris and are more vulnerable than concrete dams (Rico et al. 2008). of The tailings and the pond water generally contain heavy metals and various toxic chemicals used in ore extraction. Thus, the release of tailings due to a dam-break can have severe ecological consequences in the environment. A tailings dam-break has many similarities with a common dam-break flow. It is highly transient and can be severely descructive. However, a significant difference is that the released sediment-water mixture will behave as a non-Newtonian flow. Existing numerical models used to simulate dam-break flows do not represent correctly the non-Newtonian behavior of tailings under a dam-break flow and may lead to unrealistic and incorrect results. The need for experiments to extract both qualitative and quantitative information regarding these flows is therefore real and actual. The present paper explores an existing experimental data base presented in Aleixo et al. (2014a,b) to further characterize the sediment transport under conditions of a severe transient flow and to extract quantitative information regarding sediment flow rate, sediment velocity, sediment-sediment interactions a among others. Different features of the flow are also described and analyzed in detail. The analysis is made by means of imaging techniques such as Particle Image Velocimetry and Particle Tracking Velocimetry that allow extracting not only the velocity field but the Lagrangian description of the sediments as well. An analysis of the results is presented and the limitations of the presented experimental approach are discussed. References Rico, M., Benito, G., Salgueiro, AR, Diez-Herrero, A. and Pereira, H.G. (2008) Reported tailings dam failures: A review of the European incidents in the worldwide context , Journal of Hazardous Materials, 152, 846-852 . Aleixo, R., Ozeren, Y., Altinakar, M. and Wren, D. (2014a) Velocity Measurements using Particle Tracking in Tailings dam Failure experiments, Proceedings of the 3rd IAHR-Europe conference, Porto, Portugal. Aleixo, R., Ozeren, Y., Altinakar, M. (2014b) Tailing dam-break analysis by means of a combined PIV-PTV tool, Proceedings of the River Flow Conference, Lausanne, Switzerland.

  4. 3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, ...

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

    3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, LOOKING NORTHEAST. A SIX-FOOT SCALE IS LOCATED AGAINST WALL ON LEFT. PURPOSE OF TANK IS UNKNOWN, BUT APPEARS TO HAVE FALLEN FROM ITS ORIGINAL LOCATION AT THE MILL SITE, UP AND TO THE RIGHT OF THIS VIEW. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

  5. Design of tailing dam using red mud

    NASA Astrophysics Data System (ADS)

    Rout, Subrat; Sahoo, Tapaswini; Das, Sarat

    2013-06-01

    Red mud, waste industrial product from aluminum industries produced approximately 75 million tonnes every year with less than half of this is used. Storage of this unutilized red mud takes vast tracts of usable land and pollutes, land, air and water. Construction of high embankments, under passes, flyovers, tailing dams uses vast tract of natural resources (top soil) is also matter of concern as its takes thousands of years to form the natural soil. This paper discusses use of red mud for construction of tailing dam based on laboratory findings and finite element analysis. The geotechnical properties such as plasticity, compaction, permeability, shear strength characteristics and dispersion of red mud are presented. Stability and seepage analysis of tailing dams as per finite element analysis using the above geotechnical parameters is presented.

  6. FORMATION AND FAILURE OF NATURAL DAMS.

    USGS Publications Warehouse

    Costa, John E.; Schuster, Robert L.

    1988-01-01

    Of the numerous kinds of dams that form by natural processes, dams formed from landslides, glacial ice, and late-neoglacial moraines present the greatest threat to people and property. Landslide dams form a wide range of physiographic settings. The most common types of mass movements that form landslide dams are rock and debris avalanches; rock and soil slumps and slides; and mud, debris, and earth flows. The most common initiation mechanisms for dam-forming landslides are excessive rainfall and snowmelt and earthquakes. Natural dams may cause upstream flooding as the lake rises and downstream flooding as a result of failure of the dam. Although data are few, for the same potential energy at the dam site, downstream flood peaks from the failure of glacier-ice dams are smaller than those from landslide, moraine, and constructed earth-fill and rock-fill dam failures.

  7. The formation and failure of natural dams

    USGS Publications Warehouse

    Costa, J.E.; Schuster, R.L.

    1987-01-01

    Of the numerous kinds of dams that form by natural processes, dams formed from landslides, glacial ice, and neoglacial moraines present the greatest threat to people and property. The most common types of mass movements that form landslide dams are rock and debris avalanches, rock and soil slumps and slides, and mud, debris, and earth flows. The most common initiation mechanisms for dam-forming landslides are excessive rainfall and snowmelt and earthquakes. Landslide dams can be classified into six categories based on their relation with the valley floor. Type I dams (11%) of the 81 landslide dams around the world that were classifed do not reach from one valley side to the other. Type II dams (44%) span the entire valley flood, occasionally depositing material high up on opposite valley sides. Type III dams (41%) move considerable distances both upstream and downstream from the landslide failure. Type IV dams (1%) are rare and involve the contemporaneous failure of material from both sides of a valley. Type V dams (1%) are also rare, and are created when a single landslide sends multiple tongues of debris into a valley forming two or more landslide dams in the same surfaces, that extend under the stream or valley and emerge on the opposite valley side. Many landslide dams fail shortly after formation. Overtopping is by far the most common cause of failure. Glacial ice dams can produce at least nine kinds of ice-dammed lakes. The most dangerous are lakes formed in main valleys dammed by tributary glaciers. Failure can occur by erosion of a drainage tunnel under or through the ice dam or by a channel over the ice dam. Cold polar ice dams generally drain supraglacially or marginally by downmelting of an outlet channel. Warmer temperate-ice dams tend to fail by sudden englacial or subglacial breaching and drainage. Late neoglacial moraine-dammed lakes are located in steep mountain areas affected by the advances and retreats of valley glaciers in the last several centuries. The most common reported failure mechanism is overtopping and breaching by a wave or series of waves in the lake, generated by icefalls, rockfalls, or snow or rock avalanches. Melting of ice-cores or frozen ground and piping and seepage are other possible failure mechanisms. (Lantz-PTT)

  8. 12. Credit PED. View of tail race and dam showing ...

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

    12. Credit PED. View of tail race and dam showing dumping of construction rubble into river bed by rail car; and preparations for pouring a concrete cap onto tail race wall. Photo c. 1909. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  9. Dam Failure Inundation Map Project

    NASA Technical Reports Server (NTRS)

    Johnson, Carl; Iokepa, Judy; Dahlman, Jill; Michaud, Jene; Paylor, Earnest (Technical Monitor)

    2000-01-01

    At the end of the first year, we remain on schedule. Property owners were identified and contacted for land access purposes. A prototype software package has been completed and was demonstrated to the Division of Land and Natural Resources (DLNR), National Weather Service (NWS) and Pacific Disaster Center (PDC). A field crew gathered data and surveyed the areas surrounding two dams in Waimea. (A field report is included in the annual report.) Data sensitivity analysis was initiated and completed. A user's manual has been completed. Beta testing of the software was initiated, but not completed. The initial TNK and property owner data collection for the additional test sites on Oahu and Kauai have been initiated.

  10. Environmental Risk Assessment System for Phosphogypsum Tailing Dams

    PubMed Central

    Sun, Xin; Tang, Xiaolong; Yi, Honghong; Li, Kai; Zhou, Lianbi; Xu, Xianmang

    2013-01-01

    This paper may be of particular interest to the readers as it provides a new environmental risk assessment system for phosphogypsum tailing dams. In this paper, we studied the phosphogypsum tailing dams which include characteristics of the pollution source, environmental risk characteristics and evaluation requirements to identify the applicable environmental risk assessment methods. Two analytical methods, that is, the analytic hierarchy process (AHP) and fuzzy logic, were used to handle the complexity of the environmental and nonquantitative data. Using our assessment method, different risk factors can be ranked according to their contributions to the environmental risk, thereby allowing the calculation of their relative priorities during decision making. Thus, environmental decision-makers can use this approach to develop alternative management strategies for proposed, ongoing, and completed PG tailing dams. PMID:24382947

  11. 1. VIEW OF THE MILL TAILINGS FACING NORTHWEST. SEDIMENT DAM ...

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

    1. VIEW OF THE MILL TAILINGS FACING NORTHWEST. SEDIMENT DAM AND POND IN THE FOREGROUND, AND WATER PUMP (FEATURE B-25) ON THE LOWER RIGHT SIDE OF PHOTO. - Nevada Lucky Tiger Mill & Mine, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  12. 2. VIEW OF EAST TAILING DAM (FOREGROUND), LOOKING EAST SOUTHEAST ...

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

    2. VIEW OF EAST TAILING DAM (FOREGROUND), LOOKING EAST SOUTHEAST UP WASH TOWARD ORE BIN, OVERBURDEN, ADITS, AND ROAD SHOWN IN CA-290-1. MILL SITE IS UP AND TO THE RIGHT OF THIS VIEW. STANDARD FIFTY-GALLON DRUM IN FOREGROUND GIVES SCALE OF WALL. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

  13. Tailings dams stability analysis using numerical modelling of geotechnical and geophysical data

    NASA Astrophysics Data System (ADS)

    Mihai, S.; Zlagnean, M.; Oancea, I.; Petrescu, A.

    2009-04-01

    Methods for monitoring seepage and detecting internal erosion are essential for the safety evaluation of embankment dams. Internal erosion is one of the major reasons for embankment dam failures, and there are thousands of large tailings dams and waste-rock dumps in the world that may pe considered as hotspots for environmental impact. In this research the geophysical survey works were performed on Cetatuia 2 tailings dam. Electrical resistivity imaging (ERI) method was able to detect spatially anomalous zones inside the embankment dam. These anomalies are the results of internal erosion phenomena which may progressing inside the dam and is difficult to detect by conventional methods. Data aquired by geophysical survey together with their interpretations were used in the numerical model for slope stability assessment. The final results show us the structural weakness induced by the presence of internal erosion elements especially for seismic loading case. This research methodology may be also available for tailings dam monitoring purposes. Electrical Rezistivity Imaging (ERI) was performed on Cetatuia 2 dam at the Uranium Milling Plant Feldioara, in order to map areas with lateral and vertical changes in resistivity. The electrodes are connected to an automated computer operated switch box that selects the 4 electrodes to be used. A computer controls the switch box and the measuring device, and runs a program that selects the electrodes, makes the measurement, and stores the measurement. For inversion processing procedures was used Res2Din software. The measured resistivity were plotted by the pseudo section contouring method. There are five resistivity pseudosections obtained from the Cetatuia 2 tailings dam during the october 2007 measurements. Four transversal profiles trans1 to trans4 are perpendicular to the berms and the longitudinal one long1 is placed along dam's crest. The high resistivities near the berms surfaces corresponds to unsaturated fill materials and the low resistivities near the crest correspond to water saturated material. The resistivities values greater then 80 ohm.m may be explained by some error obtained for that inversion model. Profiles trans3 and trans4 were measured on perpendicular directions to berm alignment and show two distinct zones. The upward low resistivities zone correspond to water saturated materials especially from the compacted clay dam's core and the downward high resistivities zone belongs to unsaturated fill materials. The boundary between high and low resistivity at the depth of about 5 to 7 meters shows the groundwater level. The continuation of the high resistivity zones towards the end of the profile trans3, which is different from other profiles is probably due to the presence of dry coarse materials in shallow depth correspondingly to sandy clay. The sand fractions from the clay matrix may be affected by internal erosional phenomena, due to seepage currents that overpassed the material critical gradient. In this case the relative high resistivities values were considered as a presumptive erosional pattern. This profile was considered for the slope stability finite element modelling. The profile long1 which is placed along dam's crest is the longest profiles and extends up to nearly 420 m. The boundary between high and low resistivity at the depth of about 4 to 8 meters shows the groundwater across the dam core. The central part of the profile (about meter 200) shows the same relative high resistivities that occurred on transversal profile trans3. Resistivity data was used for building the 3D electrical resistivity model. The water saturated materials have locations very close to dam's crest (resistivity values usually lower then 10 ohm.m) and on both dam's arms. The groundwater levels were confirmed by the piezometric measurements. Electrical Rezistivity Imaging method had the possibility to show the most important disturbant elements that in certain conditions may weak the dam's state of safety. This study considered the SSR (Shear Strength Reduction) technique for sl

  14. Field Experimental Analysis of Prototype Twin Dam Failure Phenomenon

    NASA Astrophysics Data System (ADS)

    Tseng, Fu-Min; Chen, Su-Chin; An, Hsiuan-Pei

    2015-04-01

    We constructed a full scale two-dam system in Landao Creek, Huisun forest, Taiwan. From its own alluvium to investigate the dam break morphology and physical properties between two dams with three intervals in 16.2m (case 1), 32.4m (case 2) and 64.8m (case 3). We adjusted the interval by fixed upstream dam and changed downstream dam site to observed and analyzed dam failure processes and hydraulic properties of the dam system. Grain size distribution investigation and 3D Lidar model of the stream bed were executed before and after dams break to discuss the river morphology evolution. In addition, to explore the type of breach varying with time, we used the method of 3D Remodeling from Motion Structure with Multi-View Stereo, which is a 3D spatial modeling process by photoing an object at same time in more than four different angles with over 70% overlap to each other, to construct the 3D model of dams system in this study. Furthermore, the dam break process were analyzed by cameras images and data recorded from water level gauges. The result showed that the shortest intervals in Case 1 result in a stronger torrent impact at upstream side of downstream dam, more significant reduction in dam intensity and wider breach which was 22% more than that in Case 2. On the contrary, the failure duration between two dams in Case 3 was 4.0 and 2.7 times longer than that in Case 1 and Case 2, respectively. Consequently, the decrement of dam interval led to a greater damage and rapid increment of water level which was prompted by outburst flow from the upstream dam failure at downstream dam, and shorter failure duration in two-dam system. In addition, the transport distance of sediment which yielded from upstream dam breach depend on whether downstream was obstructed or not. The 90% sediment of upstream dam breach were deposited on the upstream side of downstream dam with a comparison of entire loss in case of downstream dam.

  15. Experiences from the small historical dams failures during heavy floods

    NASA Astrophysics Data System (ADS)

    Vaní?ek, I.; Vaní?ek, M.; Jirásko, D.; Pecival, T.

    2015-09-01

    Roughly between 400 and 600 years ago many small earth dams were constructed mainly in the south part of the Czech Republic. They were used for fish production and flood protection. To our days roughly one third survived, which means about 25 000 of them. During catastrophic floods in 2002 many of them had some problems but less than 0.3% failed. Experiences gained from the failure evaluation are presented. Firstly from the view of limit states of failures, when limit states of internal erosion and surface erosion played most important role and were the main reason of failures. Secondly, from the view of so called domino effect of failure, when the most important dam on the catchment basin failed and after that the other ones, situated below, had limited chance to survive. The failures are described for catchment basin of the small river Lomnice in south part of the Czech Republic close to the town Blatna. The experiences obtained there led to the evaluation of other catchment basins where domino effect of failure can play also very important role. For the evaluation of potential risk, the numerical modelling was used to study the flood wave propagation below the critical dam, especially at the moment when this wave is reaching the dam situated below the critical one. Finally, the recommendations are specified, not only for individual dams but also for catchment basin, where the risk of domino effect failure is very high.

  16. Dam failure analysis for the Lago de Matrullas Dam, Orocovis, Puerto Rico

    USGS Publications Warehouse

    Torres-Sierra, Heriberto; Gómez-Fragoso, Julieta

    2015-01-01

    Results from the simulated dam failure of the Lago de Matrullas Dam using the HEC–RAS model for the 6- and 24-hour PMP events showed peak discharges at the dam of 3,149.33 and 3,604.70 m3/s, respectively. Dam failure during the 100-year-recurrence, 24-hour rainfall event resulted in a peak discharge of 2,103.12 m3/s directly downstream from the dam. Dam failure under sunny day conditions produced a peak discharge of 1,695.91 m3/s at the dam assuming the antecedent lake level was at the morning-glory spillway invert elevation. Flood-inundation maps prepared as part of the study depict the flood extent and provide valuable information for preparing an Emergency Action Plan. Results of the failure analysis indicate that a failure of the Lago de Matrullas Dam could cause flooding to many of the inhabited areas along stream banks from the Lago de Matrullas Dam to the mouth of the Río Grande de Manatí. Among the areas most affected are the low-lying regions in the vicinity of the towns of Ciales, Manatí, and Barceloneta. The delineation of the flood boundaries near the town of Barceloneta considered the effects of a levee constructed during 2000 at Barceloneta in the flood plain of the Río Grande de Manatí to provide protection against flooding to the near-by low-lying populated areas. The results showed overtopping can be expected in the aforementioned levee during 6- and 2

  17. Dynamic model failure tests of dam structures Dalian University of Technology, Dalian 116024, China

    E-print Network

    Spencer Jr., Billie F.

    Dynamic model failure tests of dam structures Gao Lin Dalian University of Technology, Dalian 116024, China ABSTRACT: For the earthquake safety evaluation of dam structures, it is desirable to extend failure tests of a number of concrete gravity dams, concrete arch dams and embankment dams have been

  18. Estimating Overall Risk of Dam Failure: Practical Considerations in Combining Failure Probabilities ANCOLD 2003 Risk Workshop Page 1

    E-print Network

    Bowles, David S.

    Estimating Overall Risk of Dam Failure: Practical Considerations in Combining Failure Probabilities ANCOLD 2003 Risk Workshop Page 1 ESTIMATING OVERALL RISK OF DAM FAILURE: PRACTICAL CONSIDERATIONS With the move to a risk based approach to dam safety there has been a concomitant focus on estimating

  19. Close-range photogrammetric reconstruction of moraine dam failures

    NASA Astrophysics Data System (ADS)

    Westoby, M. J.; Brasington, J.; Glasser, N. F.; Hambrey, M. J.; Reynolds, J. M.

    2012-04-01

    Glacial Lake Outburst Floods (GLOFs) from moraine-dammed lakes represent a high magnitude, low frequency catastrophic glacio-fluvial phenomena, with the potential to cause significant damage to property and infrastructure in high-mountain regions. Detailed accounts of GLOF dynamics, in particular the initiation and propagation of dam breaching are extremely rare, owing to their occurrence in often remote, inaccessible areas, as well as the impracticalities associated with attempting to directly instrument such high magnitude, turbulent flows. In addition to the dearth of detailed, first-hand observations of dam failures, reconstruction of breaches and failure mechanisms derived from morphological evidence is hampered by the lack of high-quality, high-resolution DTMs of remote alpine areas. Previous studies have therefore resorted to the use of coarse resolution data products (SRTM, ASTER GDEM) to quantify characteristics of failure events, e.g. pre-flood lake volume, dam height/width, which may give rise to considerable uncertainty in related numerical simulations and assessments of downstream flood hazards. In this paper we employ a novel low-cost, close-range photogrammetric technique, termed 'Structure-from-Motion' (SfM) to provide detailed in-situ reconstructions of dam and valley topography for two moraine dam complexes which have produced historical GLOFs in the Khumbu Himal, Nepal. Requiring little more than a consumer-grade digital camera and suitable ground control for implementation, the resolution of the final data products are comparable to that obtained using ground-based or airborne LiDAR. These data facilitate the extraction of precise estimates of dam (and breach) geometry, volumes of water and sediment removed during the outburst events, and the downstream channel topography. We conclude by directly comparing such key metrics derived from low-resolution topographic datasets, with those acquired in situ using the SfM technique, and discuss the implications for the reconstruction of flood dynamics.

  20. Analysis of Dam Failure in the Saluda River February 8, 2005

    E-print Network

    Morrow, James A.

    two possible failure modes for the Saluda Dam: gradual failure due to an enlarging breach and sudden catas- trophic failure due to liqui#12;cation of the dam. For the #12;rst case we de- scribe the breach can follow two distinct courses: #12; Team 36 Page 4 of 22 #15; A crack or breach forms in the dam

  1. Prediction of a hydrograph resulting from multiple dam failures

    SciTech Connect

    Nicholas, G.D.; Tapp, J.S.

    1980-12-01

    This paper presents the results of a case study to determine the hydrograph resulting from the failure of four dams located in series during a catastrophic storm event. These impoundments serve as water supply storage and sediment control for a coal preparation facility. The structures were classified as high hazard because of the coal washing operation and the underground mines located immediately downstream. In order to pass the catastrophic design storm through the spillway of the most downstream structure, determining flows from multiple failure was accomplished. The results presented include the increase in discharge for each successive dam failure and the effect of various parameters, such as time to develop maximum breach size and width of breach, on peak discharge.

  2. Using Runoff Hydrograph Model for Early Detecting Landslide Dam Failure

    NASA Astrophysics Data System (ADS)

    Chompuchan, C.; Chen, W. L.; Lin, C. Y.

    2014-12-01

    In mountainous areas, many studies explored that during extreme rainfall event induced landslide dams failure and consequently caused the catastrophe damage of lives and infrastructures at the downstream of the watershed. The detection of initial landslide dam formation and the estimation of its occurrence position in the upstream were essential to warn the residents and evacuate in advance. The devices currently used, such as wire sensor, geophone sensor, and infrared cameras (CCD) are classified as the post-event type sensor, which only has a shorter response time, and can just hardly satisfy the requirement which people expect from precaution system. To predict disasters earlier and increase response time, this study used the change point derived from comparing theoretical and observing runoff hydrograph. Chishan River watershed was selected as a case study. Grid Rational Algorithm for Predicting Hydrograph (GRAPH), the dynamic rainfall - runoff model, was used to calibrate watershed runoff hydrograph parameter. The landslide dams were simulated at difference distances along the river, and the runoff hydrographs were compared. Then, the rainfall data and landslide dam failure during Typhoon Morakot in August 2009 was verified the model.The result showed that, during the initial landslide dam formation, the observed accumulate and peak flow hydrograph reduced significantly in comparison with theoretical flow. This model can be applied to establish an efficient warning system for debris flow occurring precaution. In addition, this study has been improved for a longer response time by integrating traditional observation system and runoff hydrograph warning systems and can provide to the references of related authorities.

  3. Dynamic decision making for dam-break emergency management - Part 2: Application to Tangjiashan landslide dam failure

    NASA Astrophysics Data System (ADS)

    Peng, M.; Zhang, L. M.

    2013-02-01

    Tangjiashan landslide dam, which was triggered by the Ms = 8.0 Wenchuan earthquake in 2008 in China, threatened 1.2 million people downstream of the dam. All people in Beichuan Town 3.5 km downstream of the dam and 197 thousand people in Mianyang City 85 km downstream of the dam were evacuated 10 days before the breaching of the dam. Making such an important decision under uncertainty was difficult. This paper applied a dynamic decision-making framework for dam-break emergency management (DYDEM) to help rational decision in the emergency management of the Tangjiashan landslide dam. Three stages are identified with different levels of hydrological, geological and social-economic information along the timeline of the landslide dam failure event. The probability of dam failure is taken as a time series. The dam breaching parameters are predicted with a set of empirical models in stage 1 when no soil property information is known, and a physical model in stages 2 and 3 when knowledge of soil properties has been obtained. The flood routing downstream of the dam in these three stages is analyzed to evaluate the population at risk (PAR). The flood consequences, including evacuation costs, flood damage and monetized loss of life, are evaluated as functions of warning time using a human risk analysis model based on Bayesian networks. Finally, dynamic decision analysis is conducted to find the optimal time to evacuate the population at risk with minimum total loss in each of these three stages.

  4. Data collection and documentation of flooding downstream of a dam failure in Mississippi

    USGS Publications Warehouse

    Van Wilson, Jr., K.

    2005-01-01

    On March 12, 2004, the Big Bay Lake dam failed, releasing water and affecting lives and property downstream in southern Mississippi. The dam is located near Purvis, Mississippi, on Bay Creek, which flows into Lower Little Creek about 1.9 miles downstream from the dam. Lower Little Creek flows into Pearl River about 16.9 miles downstream from the dam. Knowledge of the hydrology and hydraulics of floods caused by dam breaks is essential to the design of dams. A better understanding of the risks associated with possible dam failures may help limit the loss of life and property that often occurs downstream of a dam failure. The USGS recovered flood marks at the one crossing of Bay Creek and eight crossings of Lower Little Creek. Additional flood marks were also flagged at three other bridges crossing tributaries where backwater occurred. Flood marks were recovered throughout the stream reach of about 3/4 to 15 miles downstream of the dam. Flood marks that were flagged will be surveyed so that a flood profile can be documented downstream of the Big Bay Lake dam failure. Peak discharges are also to be estimated where possible. News reports stated that the peak discharge at the dam was about 67,000 cubic feet per second. Preliminary data suggest the peak discharge from the dam failure attenuated to about 13,000 cubic feet per second at Lower Little Creek at State Highway 43, about 15 miles downstream of the dam.

  5. Signature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany

    E-print Network

    Gilli, Adrian

    , in 1974, the dam was breached 44 days after the landslide emplacement, releasing a flood with a peakSignature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany 4 November 2003; received in revised form 12 April 2004; accepted 26 April 2004 Abstract Landslide-dammed

  6. RISK-BASED EVALUATION OF OPERATING RESTRICTIONS TO REDUCE THE RISK OF EARTHQUAKE-INDUCED DAM FAILURE

    E-print Network

    Bowles, David S.

    Earthquake loadings and pool elevations, dam break-inundation modeling, and reservoir simulation. EvaluationsRISK-BASED EVALUATION OF OPERATING RESTRICTIONS TO REDUCE THE RISK OF EARTHQUAKE-INDUCED DAM and consequences of an Earthquake-induced dam failure. The potential for both a sudden overtopping failure

  7. Comparison of two process based earthen dam failure computation models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dams are an important part of this nation's infrastructure providing flood control, water supply, irrigation, hydropower, navigation, and recreation. Despite their many beneficial uses, dams present a risk to property and life due to their potential to fail. They are also a part of the nation's ag...

  8. Failure mode analysis of a post-tension anchored dam using linear finite element analysis

    NASA Astrophysics Data System (ADS)

    Corn, Aimee

    There are currently over 84,000 dams in the United States, and the average age of those dams is 52 years. Concrete gravity dams are the second most common dam type, with more than 3,000 in the United States. Current engineering technology and technical understanding of hydrologic and seismic events has resulted in significant increases to the required design loads for most dams; therefore, many older dams do not have adequate safety for extreme loading events. Concrete gravity dams designed and constructed in the early 20th century did not consider uplift pressures beneath the dam, which reduces the effective weight of the structure. One method that has been used to enhance the stability of older concrete gravity dams includes the post-tension anchor (PTA) system. Post-tensioning infers modifying cured concrete and using self-equilibrating elements to increase the weight of the section, which provides added stability. There is a lack of historical evidence regarding the potential failure mechanisms for PTA concrete gravity dams. Of particular interest, is how these systems behave during large seismic events. The objective of this thesis is to develop a method by which the potential failure modes during a seismic event for a PTA dam can be evaluated using the linear elastic finite element method of analysis. The most likely potential failure modes (PFM) for PTA designs are due to tensile failure and shear failure. A numerical model of a hypothetical project was developed to simulate PTAs in the dam. The model was subjected to acceleration time-history motions that simulated the seismic loads. The results were used to evaluate the likelihood of tendon failure due to both tension and shear. The results from the analysis indicated that the PTA load increased during the seismic event; however, the peak load in the tendons was less than the gross ultimate tensile strength (GUTS) and would not be expected to result in tensile failure at the assumed project. The analysis also indicated there was a potential for permanent horizontal displacement along the dam/foundation interface. The horizontal movement was not considered large enough to develop a shear failure of the tendons at the project. The results from this study indicate demand to capacity ratios (DCR) of 0.79 for the anchor head, 0.75 for the tendon, and 0.63 for the foundation cone failure, and a potential displacement of 0.33 inches, which is not large enough to shear the tendon. The methods developed are appropriate for the evaluation of the tensile and shear failure modes for the PTA tendons. Based on the results, it would appear that shear failure of the tendon is a more likely failure mechanism. Thus, shear failure of the tendon should be a focus of seismic evaluations.

  9. The 27 May 1937 catastrophic flow failure of gold tailings at Tlalpujahua, Michoacán, México

    NASA Astrophysics Data System (ADS)

    Macías, J. L.; Corona-Chávez, P.; Sanchéz-Núñez, J. M.; Martínez-Medina, M.; Garduño-Monroy, V. H.; García-Tenorio, F.; Cisneros-Máximo, G.

    2014-08-01

    On 27 May 1937, after one week of sustained heavy rainfall, a voluminous flood caused the death of at least 300 people and the destruction of the historic El Carmen church and several neighborhoods in the mining region of Tlalpujahua, Michoacán, central Mexico. This destructive flood was triggered by the breaching of the impoundment of the Los Cedros tailings and the sudden release of 16 Mt of water-saturated waste materials. The muddy silty flood, moving at estimated speeds of 20-25 m s-1, was channelized along the Dos Estrellas and Tlalpujahua drainages and devastated everything along its flow path. After advancing 2.5 km downstream, the flood slammed into El Carmen church and surrounding houses at estimated speeds of ~7 m s-1, destroying many of construction walls and covering the church floor with ~2 m of mud and debris. Eyewitness accounts and newspaper articles, together with analysis of archived photographic materials, indicated that the flood consisted of three muddy pulses. This interpretation is confirmed and extended by the results of our geological investigations during 2013 and 2014. Stratigraphic relations and granulometric data for selected proximal and distal samples show that the flood behaved as a hyperconcentrated flow along most of its trajectory. Even though premonitory signs of possible impoundment failure were reported days before the flood, and people living downstream were alerted, authorities ordered no evacuations or other mitigative actions. The catastrophic flood at Tlalpujahua provides a well-documented, though tragic, example of impoundment breaching of a tailings dam caused by the combined effects of intense rainfall, dam weakness, and inadequate emergency-management protocols - unfortunately an all too common case-scenario for most of the world's mining regions.

  10. SPILL ALERT DEVICE FOR EARTH DAM FAILURE WARNING

    EPA Science Inventory

    A spill alert device for determining earth dam safety based on the monitoring of the acoustic emissions generated in a deforming soil mass was developed and field-tested. The acoustic emissions are related to the basic mechanisms from which soils derive their strength. Laboratory...

  11. Laboratory study of the clogging process and factors affecting clogging in a tailings dam

    NASA Astrophysics Data System (ADS)

    Wu, Jun; Wu, Yanqing; Lu, Jian

    2008-05-01

    Laboratory simulation of clogging in the Lixi tailings dam (Shaanxi Province, China) is urgently required because clogging is an important factor affecting the dam stability. This work firstly presents the results of ferrous iron oxidation experiments using buffer solution. The results indicate that the ferrous iron oxidation follows first order kinetics, and the oxidation process is strongly dependent on pH, a higher pH resulting in a higher oxidation rate. Furthermore, when the pH exceeds 7.0, the oxidation rate constant increases significantly. Secondly, a column experiment was carried out under the conditions of the pH ranging from 6.8 to 7.5 and the natural oxygen supply. Ferrous iron oxidation and precipitation were found to reach equilibrium under these conditions. After 23 days, the column experiment was stopped when the clogging materials blocked the column outlet. The clogging materials were found to be a mixture of ferric hydroxide and its converted products, and these existed in amorphous form with a loose cluster microstructure according to the results of XRD and SEM.

  12. The potential for catastrophic dam failure at Lake Nyos maar, Cameroon

    USGS Publications Warehouse

    Lockwood, J.P.; Costa, J.E.; Tuttle, M.L.; Nni, J.; Tebor, S.G.

    1988-01-01

    The upper 40 m of Lake Nyos is bounded on the north by a narrow dam of poorly consolidated pyroclastic rocks, emplaced during the eruptive formation of the Lake Nyos maar a few hundred years ago. This 50-m-wide natural dam is structurally weak and is being eroded at an uncertain, but geologically alarming, rate. The eventual failure of the dam could cause a major flood (estimated peak discharge, 17000 m3/s) that would have a tragic impact on downstream areas as far as Nigeria, 108 km away. This serious hazard could be eliminated by lowering the lake level, either by controlled removal of the dam or by construction of a 680-m-long drainage tunnel about 65 m below the present lake surface. Either strategy would also lessen the lethal effects of future massive CO2 gas releases, such as the one that occurred in August 1986. ?? 1988 Springer-Verlag.

  13. Simulation of Inundation Zone triggered by Dam Failure using FLO-2D

    NASA Astrophysics Data System (ADS)

    Lee, K.; Kim, S. W.; Kim, J. M.

    2014-12-01

    Floods due to gradual dam breach can lead to devastating disasters with tremendous loss of life and property. Hence it is important to identify the potential risk areas for natural hazard problem such as dam failure. A numerical modeling approach is often used to build a flood hazard map caused by dam failure. The two primary tasks in the analysis of a dam breach are the prediction of the reservoir outflow hydrograph and the routing of the hydrograph through the downstream valley. The hydrograph to be routed downstream may be prescribed, and parametric models could be used to build a outflow hydrograph once breach parameters capturing breach formation and progress are specified. Even though breach growth is one of the most important parameter in building the reservoir outflow hydrograph, observations are rarely available. In the mean while lake level data is often measured during the dam failure on the real time basis and they may capture the characteristics of breach formation and progress. Thus a simple method is developed to reproduce breach formation. The breach formation is retrieved from lake level data as a function of time during dam failure event. The new method uses an optimization scheme as a primary tool. Because observation for breach formation doesn't exist, it is hard to validate the performance of the new method. Alternatively the retrieved breach formation curve is linked with a parametric dam failure model to give outflow hydrograph. Then FLO-2D is run to route the outflow hydrograph through the downstream valley for the test site. To validate the new method the simulation of FLO-2D is relatively compared with the on-site investigation for the inundation zone. The new method is promising in that it provides reasonable accuracy in the test site. Keywords: Dam failure, Natural hazard, Breach, Hydrograph AcknowledgementThis research was supported by a grant (13SCIPS01) from Smart Civil Infrastructure Research Program funded by Ministry of Land, Infrastructure and Transport(MOLIT) of Korea government and Korea Agency for Infrastructure Technology Advancement(KAIA).

  14. Late Pleistocene earthquake-triggered moraine dam failure and outburst of Lake Zurich, Switzerland

    E-print Network

    Gilli, Adrian

    Late Pleistocene earthquake-triggered moraine dam failure and outburst of Lake Zurich, Switzerland; accepted 24 December 2007; published 9 April 2008. [1] Lakes impounded by moraines may be considered of a Late Pleistocene ($13,760 calibrated years B.P.) moraine breach and subsequent Lake Zurich outburst

  15. Characteristics of Landslide Dam Failure by Practicing an Original Scale Field Experiment in Landow Creek, Huisun Experimental Forest, Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, C.; Chen, S.

    2013-12-01

    This research built two artificial landslide dams, an original scale field experiment, in Landow creek, Huisun experimental forest on November 7th 2012. The purposes are to discuss characteristics of landslide dam failure, such as variations of velocity, development of the breach, and alteration of topography. We present four CCDs at upstream and downstream sides of two artificial landslide dams and used the Unmanned Aerial Vehicle for monitoring and recording the processes of landslide dam failures. Besides, six water level sensors set up at upstream, and downstream sides of dams to identify inflow and outflow water level and determine the flow discharge; then, applying image judgments technique to determine the flow velocity and direction. Landslide dam failure proceeds with three steps, pipping, turning into retrogressive erosion, and overtopping; however, overtopping dominates the most phenomenon in this experiment. During the impoundment filling, the downstream slope of landslide dam tends to steep as the retrogressive erosion occurs. After dam failure, the impoundment filled with sedimentary deposits; in addition, the original downstream main channel develops into many new flow paths and becomes braided river morphology. The sediment concentration was inversely proportional to time at both upstream and downstream side due to the armor layer decreased. The first dam breach dimension and the impoundment volume are both smaller than the second; hence we assumed that the breach dimension and impoundment volume have a significant correlation. The research results could provide better analyzing landslide dam hazards.

  16. Characteristics of Landslide Dam Failure by Practicing an Original Scale Field Experiment in Landow Creek, Huisun Experimental Forest, Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, Su-Chin; Hsu, Tzu-Yang; Chao, Yi-Chiung

    2013-04-01

    This research built two artificial landslide dams, an original scale field experiment, in Landow creek, Huisun experimental forest on November 7th 2012. The purposes are to discuss characteristics of landslide dam failure, such as variations of velocity, development of the breach, and alteration of topography. We present four CCDs at upstream and downstream sides of two artificial landslide dams and used the Unmanned Aerial Vehicle (UAV) for monitoring and recording the processes of landslide dam failures. Besides, six water level sensors set up at upstream, and downstream sides of dams to identify inflow and outflow water level and determine the flow discharge; then, applying image judgments technique to determine the flow velocity and direction. Moreover, 3D LiDar scanner used to analyze the river morphology before and after the experiment. Landslide dam failure proceeds with three steps, pipping, turning into retrogressive erosion, and overtopping; however, overtopping dominates the most phenomenon in this experiment. During the impoundment filling, the downstream slope of landslide dam tends to steep as the retrogressive erosion occurs. After dam failure, the impoundment filled with sedimentary deposits; in addition, the original downstream main channel develops into many new flow paths and becomes braided river morphology. The momentary velocity of dam outbreak was nearly three times the inflow velocity; then the momentary discharge from the first failed dam to second dam was over more than 50 times the inflow discharge. The sediment concentration was inversely proportional to time at both upstream and downstream side due to the armor layer decreased. There are two outburst breaches processes, V and U types. The breaches development of two dams were both from V to U type, and vertical degradation to horizontal extension. The first breach dimension and the impoundment volume are both smaller than the second dam; hence we assumed that the breach dimension and impoundment volume have a significant correlation. The research results could provide better analyzing landslide dam hazards.

  17. DAM Safety and Deformation Monitoring in Dams

    NASA Astrophysics Data System (ADS)

    Kalkan, Y.; Bilgi, S.; Potts, L.; Miiama, J.; Mahgoub, M.; Rahman, S.

    2013-12-01

    Water is the life and necessity to water is increasing day by day with respect to the World population, rising of living standards and destruction of nature. Thus, the importance of water and water structures have been increasing gradually. Dams are among the most important engineering structures used for water supplies, flood controls, agricultural purposes as well as drinking and hydroelectric power. There are about 150.000 large size dams in the World. Especially after the Second World War, higher and larger capacity dams have been constructed. Dams create certain risks like the other manmade structures. No one knows precisely how many dam failures have occurred in the World, whereas hundreds of dam failures have occurred throughout the U.S. history. Some basic physical data are very important for assessing the safety and performance of dams. These are movement, water pressure, seepage, reservoir and tail-water elevations, local seismic activities, total pressure, stress and strain, internal concrete temperature, ambient temperature and precipitation. These physical data are measured and monitored by the instruments and equipment. Dams and their surroundings have to be monitored by using essential methods at periodic time intervals in order to determine the possible changes that may occur over the time. Monitoring programs typically consist of; surveillance or visual observation. These programs on dams provide information for evaluating the dam's performance related to the design intent and expected changes that could affect the safety performance of the dam. Additionally, these programs are used for investigating and evaluating the abnormal or degrading performance where any remedial action is necessary. Geodetic and non-geodetic methods are used for monitoring. Monitoring the performance of the dams is critical for producing and maintaining the safe dams. This study provides some information, safety and the techniques about the deformation monitoring of the dams. Therefore, this study gives essential information about the dam safety and related analysis. Monitoring of dams is crucial since deformation might have occurred as a result of erosion, water load, hydraulic gradients, and water saturation. The case study is the deformation measurements of Ataturk Dam. This dam was constructed on Firat River and it has importance for providing drinking water, hydroelectric power and especially irrigation. In addition, brief information is given about this dam and the methods of geodetic and non-geodetic monitoring measurements applied by various disciplines. Geodetic monitoring methods are emphasized in this study. Some results have been obtained from this method for nearly seven years are presented in this work. In addition, some deformation predictions have been made especially for the cross sections where the maximum deformations took place.

  18. TAILINGS FANS AND VALLEY-SPUR CUTOFFS 869 Copyright 2004 John Wiley & Sons, Ltd. Earth Surf. Process. Landforms 29, 869882 (2004)

    E-print Network

    James, L. Allan

    2004-01-01

    of natural earthfill dam spillway not prone to catastrophic failures. Tailing fans, valley-spur cutoffs be relevant to potential dam-removal scenarios for reintroduction of salmon to these rivers. High levels Superfund cleanup site to remove mercury. Some large tailings fans dammed main channels resulting in lakes

  19. In-situ gamma-ray survey of rare-earth tailings dams - A case study in Baotou and Bayan Obo Districts, China.

    PubMed

    Li, Baochuan; Wang, Nanping; Wan, Jianhua; Xiong, Shengqing; Liu, Hongtao; Li, Shijun; Zhao, Rong

    2016-01-01

    An in-situ gamma-ray spectrometer survey with a scintillation detector of NaI(Tl) (?75 mm × 75 mm) was carried out in the Baotou and Bayan Obo Districts in order to estimate the levels of natural radionuclides near rare-earth (RE) tailings dams. In the RE tailings dam of Baotou, the mean concentrations of (238)U and (232)Th were 3.0 ± 1.0 mg/kg (range: 1.9-4.6 mg/kg) and 321 ± 31 mg/kg (range: 294-355 mg/kg), respectively. In the Bayan Obo tailings dam, the mean concentrations of (238)U and (232)Th were 5.7 ± 0.5 mg/kg (range: 5.3-6.1 mg/kg) and 276 ± 0.5 mg/kg (range: 275.5-276.3 mg/kg), respectively. The average (232)Th concentrations in the mining areas of the Bayan Obo Mine and the living areas of the Bayan Obo Town were 18.7 ± 7.5 and 26.2 ± 9.1 mg/kg, respectively. The (232)Th concentration recorded in the tailings dams was much higher than the global average (7.44 mg/kg). Our investigation shows that the (232)Th concentration in the tailings in the Baotou dam was 34.6 times greater than that in the local soil (in Guyang County); the average concentrations of (232)Th in the soil in the Baotou District and Bayan Obo Districts were about 1.35 and 2.82 times greater, respectively, than that in the soil in Guyang County. Based on our results, the highest estimated effective dose due to gamma irradiation was 1.15 mSv per year, estimated from the data observed in the Baotou tailings dams. The results of this preliminary study indicate the potential importance of radioactivity in RE tailings dams and that remedial measures may be required. PMID:26555365

  20. Laboratory experiments on dam-break flow of water-sediment mixtures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dams induce sedimentation and store significant amounts of sediment as they age; therefore, dam failures often involve the release of sediment-laden water to the downstream floodplain. In particular, tailings dams, which are constructed to impound mining wastes, can cause devastating damage when the...

  1. Moraine-dammed lake failures in Patagonia and assessment of outburst susceptibility in the Baker Basin

    NASA Astrophysics Data System (ADS)

    Iribarren Anacona, P.; Norton, K. P.; Mackintosh, A.

    2014-12-01

    Glacier retreat since the Little Ice Age has resulted in the development or expansion of hundreds of glacial lakes in Patagonia. Some of these lakes have produced large (? 106 m3) Glacial Lake Outburst Floods (GLOFs) damaging inhabited areas. GLOF hazard studies in Patagonia have been mainly based on the analysis of short-term series (? 50 years) of flood data and until now no attempt has been made to identify the relative susceptibility of lakes to failure. Power schemes and associated infrastructure are planned for Patagonian basins that have historically been affected by GLOFs, and we now require a thorough understanding of the characteristics of dangerous lakes in order to assist with hazard assessment and planning. In this paper, the conditioning factors of 16 outbursts from moraine-dammed lakes in Patagonia were analysed. These data were used to develop a classification scheme designed to assess outburst susceptibility, based on image classification techniques, flow routine algorithms and the Analytical Hierarchy Process. This scheme was applied to the Baker Basin, Chile, where at least seven moraine-dammed lakes have failed in historic time. We identified 386 moraine-dammed lakes in the Baker Basin of which 28 were classified with high or very high outburst susceptibility. Commonly, lakes with high outburst susceptibility are in contact with glaciers and have moderate (> 8°) to steep (> 15°) dam outlet slopes, akin to failed lakes in Patagonia. The proposed classification scheme is suitable for first-order GLOF hazard assessments in this region. However, rapidly changing glaciers in Patagonia make detailed analysis and monitoring of hazardous lakes and glaciated areas upstream from inhabited areas or critical infrastructure necessary, in order to better prepare for hazards emerging from an evolving cryosphere.

  2. Hydrology, geomorphology, and dam-break modeling of the July 15, 1982, Lawn Lake Dam and Cascade Lake Dam failures, Larimer County, Colorado

    USGS Publications Warehouse

    Jarrett, R.D.; Costa, J.E.

    1984-01-01

    On July 15, 1982, Lawn Lake Dam, a 26-foot-high earthfill irrigation dam built in 1903 in Rocky Mountain National Park, Colorado, failed, due to piping, releasing 674 acre-feet of water with a peak discharge of 18,000 cubic feet per second down the Roaring River. Three people were killed, and damages were estimated at $31 million. Cascade Lake Dam, downstream from Lawn Lake Dam, subsequently failed as a result of the flood, increasing the peak flow at this point from 7,210 cubic feet per second to 16,000 cubic feet per second. The flood wave took 3.28 hours to travel 12.5 miles to Lake Estes, where all the floodwater was stored. The channel of the Roaring River was scoured as much as 50 feet and widened 300 feet. An alluvial fan of 42.3 acres, containing 10 million cubic feet of material, was deposited at the mouth of the Roaring River, damming the Fall River and forming a 17-acre lake. Various methods were used to indirectly compute peak discharge, attenuation of flow, and flood traveltime. A version of the National Weather Service dam-break flood model was used to evaluate its performance on high-gradient streams, to provide supplemental hydrologic information, and to evaluate various scenarios of dam-break development. (USGS)

  3. Atrophy and growth failure of rat hindlimb muscles in tail-cast suspension

    NASA Technical Reports Server (NTRS)

    Jaspers, S. R.; Tischler, M. E.

    1984-01-01

    The primary objective of the present study is related to an evaluation of a modified tail-cast suspension model as a means of identifying metabolic factors which control or are associated with muscle atrophy and growth failure. Two different control conditions (normal and tail-casted weight bearing) were studied to determine the appropriate control for tail-cast suspension. A description is presented of a model which is most useful for studying atrophy of hindlimb muscles under certain conditions. Female Sprague-Dawley rats were employed in the experiments. Attention is given to growth rate and urinary excretion of urea and ammonia in different types of rats, the relationship between body weight and skeletal muscle weight, and the relationship between animal body weight and rates of protein synthesis and protein degradation.

  4. Reconstructing western Grand Canyon's lava dams and their failure mechanisms: new insights from geochemical correlation and 40Ar/39Ar dating

    NASA Astrophysics Data System (ADS)

    Crow, R.; Karlstrom, K. E.; McIntosh, W. C.; Peters, L.; Dunbar, N. W.

    2010-12-01

    New geochemical analyzes and 40Ar/39Ar dating of lava dam remnants allows for the more accurate reconstruction of the timing, extent, and structure of western Grand Canyon’s lava dams. Whole-rock major, trace, and rare-earth element (REE) analyzes on over 60 basaltic lava dam remnants, cascades, plugs, and basaltic alluvium, show compositional variation from basanites to alkali basalts to tholeiites. Whitmore Canyon flows, for example, are some of the only tholeiitic flows and have a distinguishable trace and REE composition, which allows for correlation of dam remnants. Over 30 new high-precision 40Ar/39Ar dates also aid in remnant correlation and establish a better-constrained sequence of intra-canyon lava dams. Reliable 40Ar/39Ar dates on western Grand Canyon’s intra-canyon basalts range from ca. 100 ka to 840 ka (new date). The best understood lava dam formed from tholeiitic flows that erupted on the north rim, flowed down Whitmore side canyon and blocked a 6-km-long reach of the Grand Canyon. The youngest of these flows is unique because we know its age (200ka), its composition (tholeiitic), and the exact area where it entered Grand Canyon. The highest flow in the resulting dam, Whitmore Cascade, is capped with very coarse basaltic alluvium that previous workers have attributed to an upstream catastrophic dam failure event at about 200 ka. However, strong similarities between the geochemistry and age of the alluvium with the underlying Whitmore Cascade flow suggest that the alluvial deposit is related to failure of the 200 ka Whitmore Cascade dam itself. Similarly the 100 ka Upper Gray Ledge flow is commonly overlain by a balsaltic alluvium that is indistinguishable in terms of age and geochemistry from the underlying Upper Gray Ledge flow. These observations lead to a new model for Grand Canyon lava dams by which lava dams undergo multi-staged failure where the upstream parts of dams fail quickly (sometimes catastrophically) but downstream parts are longer lived because they undergo less interaction with river water and fracturing and generally fill dry portions of the river bed. Identification of far-traveled clasts on top of lava dam remnants in at least two locations supports the idea that the stable Colorado River established itself on top of the distal parts of some lava dams. Thus, whereas previous workers reported that deposits from outburst flood dam failure events exist in western grand canyon, our data identify specific dam failures and an interaction of catastrophic events at the head of lava dams and modified fluvial processes in distal portions of dams.

  5. Sediment quality in Rio Guadiamar (SW, Spain) after a tailing dam collapse: contamination, toxicity and bioavailability.

    PubMed

    Riba, Inmaculada; Delvalls, T Angel; Reynoldson, Trefor B; Milani, Danielle

    2006-09-01

    An integrated assessment of sediment quality in the Guadiamar River after a mining spill was conducted. The concentration of different metals and other conventional parameters were measured in sediments located along the river. Four sediment toxicity tests (Hyalella azteca 28-day survival and growth test; Chironomus riparius 10-day survival and growth test; Hexagenia spp. 21-day survival and growth test; and Tubifex tubifex 28-day reproduction and survival test) were carried out to determine the effects associated with the accidental spill. The geochemical fractions of 6 metals (Fe, Mn, Zn, Cu, Pb, and Cd) were determined to establish the bioavailability of the metals. The relationship found in the concentrations of metals associated with the mobile fractions of the sediments in the sites studied is similar to the toxic mud from tailing pond and confirms that the toxic effects are associated with the metals Zn and Cd originating from the spill. PMID:16820209

  6. Lessons from a Dam Failure1 JAMI;S E. EVANS, SCUDDKR D. MACKKY, JOHAN F. GOTTC.KNS, AND WILFRID M. GILL, Department of Geology, Bowling Green State

    E-print Network

    Gottgens, Hans

    -earthen dam contact. Eyewitnesses reported that collapse of the seepage pipe created a breach in the dam. Of the accumulated reservoir sediment, 9-13% was mobilized by dam breach and consequent incision (as the ChagrinLessons from a Dam Failure1 JAMI;S E. EVANS, SCUDDKR D. MACKKY, JOHAN F. GOTTC.KNS, AND WILFRID M

  7. Geochemistry of Mercury and other trace elements in fluvial tailings upstream of Daguerre Point Dam, Yuba River, California, August 2001

    USGS Publications Warehouse

    Hunerlach, Michael P.; Alpers, Charles N.; Marvin-DiPasquale, Mark; Taylor, Howard E.; DeWild, John F.

    2004-01-01

    This study was designed to characterize the particle-size distribution and the concentrations of total mercury (HgT), methylmercury (MeHg), and other constituents in sediments trapped behind Daguerre Point Dam, a 28-foot-high structure on the lower Yuba River in California. The results of the study will assist other agencies in evaluating potential environmental impacts from mobilization of sediments if Daguerre Point Dam is modified or removed to improve the passage of anadromous fish. Methylmercury is of particular concern owing to its toxicity and propensity to bioaccumulate. A limited amount of recent work on hydraulic and dredge tailings in other watersheds has indicated that mercury and MeHg concentrations may be elevated in the fine-grained fractions of placer mining debris, particularly clay and silt. Mercury associated with tailings from placer gold mines is a source of continued contamination in Sierra Nevada watersheds and downstream water bodies, including the Sacramento?San Joaquin Delta and the San Francisco Bay of northern California. Churn drilling was used to recover sediments and heavy minerals at 5-foot intervals from six locations upstream of Daguerre Point Dam. Maximum depth of penetration ranged from 17.5 to 35 feet below land surface, resulting in 31 discreet drilled intervals. Drilling in permeable, unconsolidated sediments below the streambed of the Yuba River released a significant volume of water along with the sediment, which complicated the sampling and characterization effort. Overflow of a silty fraction sampled at the drill site contained suspended sediment consisting predominantly of silt and clay, with HgT concentration ranging from 33 to 1,100 ng/g (nanogram per gram) dry weight. A sandy fraction, collected after sieving sediment through a 2-millimeter vibratory screen, contained from 14 to 82 percent sand and 1 to 29 percent silt plus clay, and had HgT concentrations ranging from 6.8 to 81 ng/g dry weight. A clay-silt fraction, sampled from material remaining in suspension after the sandy fraction settled for 15-20 minutes, contained mercury concentrations from 23 to 370 ng/g dry weight. Concentrations of MeHg were less than the detection limit (<0.001 ng/g dry weight) in 30 of 31 samples of the sandy fraction. In the suspended clay-silt fraction, MeHg was detected in 16 of 31 samples, in which it ranged in concentration from 0.04 (estimated) to 0.61 ng/g wet weight. Potential rates of mercury methylation and demethylation were evaluated in seven samples using radiotracer methods. Mercury methylation (MeHg production) potentials were generally low, ranging from less than 0.15 to about 1.6 ng/g/d (nanogram per gram of dry sediment per day). Mercury demethylation (MeHg degradation) potentials were moderately high, ranging from 1.0 to 2.2 ng/g/d. The ratio of methylation potential (MP) to demethylation potential (DP) ranged from less than 0.14 to about 1.4 (median = 0.24, mean = 0.44, number of samples = 7), suggesting that the potential for net production of MeHg in deep sediments is generally low. The MeHg production rates and MP/DP ratios were higher in the shallower interval in two of the three holes where two depth intervals were assessed, whereas the MeHg concentrations were higher in the shallower interval for all three holes. A similar spatial distribution was found for concentrations of solid-phase sulfide (measured as total reduced sulfur and likely representing iron-sulfide and iron-disulfide compounds), which were much higher in shallower samples (about 700 to about 2,100 nanomoles per gram, dry sediment) than in deeper samples (32 to 55 nanomoles per gram, dry sediment) in these three holes. If reduced sulfur compounds are oxidized to sulfate as a consequence of sediment disturbance, the activity of sulfate-reducing bacteria might be stimulated, causing a short-term increase in methylation of inorganic Hg(II) (divalent mercury). The extent of increased Hg(II)-methylation w

  8. Formation and failure of volcanic debris dams in the Chakachatna River valley associated with eruptions of the Spurr volcanic complex, Alaska

    USGS Publications Warehouse

    Waythomas, C.F.

    2001-01-01

    The formation of lahars and a debris avalanche during Holocene eruptions of the Spurr volcanic complex in south-central Alaska have led to the development of volcanic debris dams in the Chakachatna River valley. Debris dams composed of lahar and debris-avalanche deposits formed at least five times in the last 8000-10,000 years and most recently during eruptions of Crater Peak vent in 1953 and 1992. Water impounded by a large debris avalanche of early Holocene (?) age may have destabilized an upstream glacier-dammed lake causing a catastrophic flood on the Chakachatna River. A large alluvial fan just downstream of the debris-avalanche deposit is strewn with boulders and blocks and is probably the deposit generated by this flood. Application of a physically based dam-break model yields estimates of peak discharge (Qp) attained during failure of the debris-avalanche dam in the range 104 < Qp < 106 m3 s-1 for plausible breach erosion rates of 10-100 m h-1. Smaller, short-lived, lahar dams that formed during historical eruptions in 1953, and 1992, impounded smaller lakes in the upper Chakachatna River valley and peak flows attained during failure of these volcanic debris dams were in the range 103 < Qp < 104 m3 s-1 for plausible breach erosion rates. Volcanic debris dams have formed at other volcanoes in the Cook Inlet region, Aleutian arc, and Wrangell Mountains but apparently did not fail rapidly or result in large or catastrophic outflows. Steep valley topography and frequent eruptions at volcanoes in this region make for significant hazards associated with the formation and failure of volcanic debris dams. Published by Elsevier Science B.V.

  9. Assessment of Vegetation Establishment on Tailings Dam at an Iron Ore Mining Site of Suburban Beijing, China, 7 Years After Reclamation with Contrasting Site Treatment Methods

    NASA Astrophysics Data System (ADS)

    Yan, Demin; Zhao, Fangying; Sun, Osbert Jianxin

    2013-09-01

    Strip-mining operations greatly disturb soil, vegetation and landscape elements, causing many ecological and environmental problems. Establishment of vegetation is a critical step in achieving the goal of ecosystem restoration in mining areas. At the Shouyun Iron Ore Mine in suburban Beijing, China, we investigated selective vegetation and soil traits on a tailings dam 7 years after site treatments with three contrasting approaches: (1) soil covering (designated as SC), (2) application of a straw mat, known as "vegetation carpet", which contains prescribed plant seed mix and water retaining agent (designated as VC), on top of sand piles, and (3) combination of soil covering and application of vegetation carpet (designated as SC+VC). We found that after 7 years of reclamation, the SC+VC site had twice the number of plant species and greater biomass than the SC and VC sites, and that the VC site had a comparable plant abundance with the SC+VC site but much less biodiversity and plant coverage. The VC site did not differ with the SC site in the vegetation traits, albeit low soil fertility. It is suggested that application of vegetation carpet can be an alternative to introduction of topsoil for treatment of tailings dam with fine-structured substrate of ore sands. However, combination of topsoil treatment and application of vegetation carpet greatly increases vegetation coverage and plant biodiversity, and is therefore a much better approach for assisting vegetation establishment on the tailings dam of strip-mining operations. While application of vegetation carpet helps to stabilize the loose surface of fine-structured mine wastes and to introduce seed bank, introduction of fertile soil is necessary for supplying nutrients to plant growth in the efforts of ecosystem restoration of mining areas.

  10. A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams

    USGS Publications Warehouse

    Walder, J.S.; O'Connor, J. E.; Costa, J.E.

    1997-01-01

    We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V.D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether < ??? 1 or < ??? 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.We analyze a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether ?????1 or ?????1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.

  11. A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams

    USGS Publications Warehouse

    Walder, J.S.

    1997-01-01

    We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/ D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether ?? > 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.

  12. Analyzing the spillway failure of the Montedoglio dam in Central Italy

    NASA Astrophysics Data System (ADS)

    Tarpanelli, A.; Moramarco, T.; Barbetta, S.; Melone, F.; Berni, N.; Pandolfo, C.; Morbidelli, R.

    2012-04-01

    The Montedoglio dam, built in the 1980s for irrigation and drinking water purposes, is an important reservoir on the Tiber River located in central Italy. The earth-fill dam is 64.30 m high with a drainage area of 276 km2. The water storage volume, with the water at the height of the spillway, is approximately 153 millions m3. On December 29, 2010 during final tests of the dam consisting to raising the reservoir level to the spillway crest, three concrete blocks of the spillway collapsed causing large damages in the territory downstream mainly to agriculture, infrastructures and other constructions (over 100 millions of euros of economic losses), luckily without casualties thanks also to timely action of the national/regional Civil Protection system. The discharge hydrograph following up the Montedoglio spillway collapse and its routing along the Tiber river valley are investigated here. The mathematical modelling of the reservoir depletion allows advancing well-founded hypotheses on the breach formation and in particular on the time interval in which the spillways collapsed found equal to 0.02 hours. The analysis is based on the recorded water reservoir level during the catastrophic event and on the comparison between the computed outflow discharge hydrograph and the one recorded at Gorgabuia equipped section located just downstream Montedoglio dam. The consequent dambreak flood wave is propagated downstream by using a one-dimensional model for flood wave routing and, based on the comparison between the flooded area extension estimated by the hydraulic model and the one observed through surveys and inspections carried out during the catastrophic event, the roughness calibration is addressed assessing different Manning roughness coefficient values for the main channel and the floodplains, respectively. For the analysis of the catastrophic event, data on water reservoir levels, river cross-sections geometry, discharges recorded at two gauged river sites and flooded area extension have been collected, thus getting a valuable knowledge which can be of support to improve the understanding and the management of dambreak events.

  13. Deformation Monitoring and Bathymetry Analyses in Rock-Fill Dams, a Case Study at Ataturk Dam

    NASA Astrophysics Data System (ADS)

    Kalkan, Y.; Bilgi, S.

    2014-12-01

    Turkey has 595 dams constructed between 1936 and 2013 for the purposes of irrigation, flood control, hydroelectric energy and drinking water. A major portion of the dam basins in Turkey are deprived of vegetation and have slope topography on near surrounding area. However, landscaping covered with forest around the dam basin is desirable for erosion control. In fact; the dams, have basins deprived of vegetation, fill up quickly due to sediment transport. Erosion control and forestation are important factors, reducing the sediment, to protect the water basins of the dams and increase the functioning life of the dams. The functioning life of dams is as important as the investment and construction. Nevertheless, in order to provide safety of human life living around, well planned monitoring is essential for dams. Dams are very large and critical structures and they demand the use or application of precise measuring systems. Some basic physical data are very important for assessing the safety and performance of dams. These are movement, water pressure, seepage, reservoir and tail-water elevations, local seismic activities, total pressure, stress and strain, internal concrete temperature, ambient temperature and precipitation. Monitoring is an essential component of the dam after construction and during operation and must en­able the timely detection of any behavior that could deteriorate the dam, potentially result in its shutdown or failure. Considering the time and labor consumed by long-term measurements, processing and analysis of measured data, importance of the small structural motions at regular intervals could be comprehended. This study provides some information, safety and the techniques about the deformation monitoring of the dams, dam safety and related analysis. The case study is the deformation measurements of Atatürk Dam in Turkey which is the 6th largest dam of world considering the filling volume of embankment. Brief information is given about the dam and the methods of monitoring techniques applied by various disciplines. Some results have been obtained from this method for nearly eight years are presented in this work. In addition, the results of bathymetric surveys between 2005 and 2010 will be compared using the cross sections where the maximum changes occurred on the dam bottom of the reservoir area.

  14. The 1916 catastrophic flood following the Bílá Desná dam failure: The role of historical data sources in the reconstruction of its geomorphologic and landscape effects

    NASA Astrophysics Data System (ADS)

    Raška, Pavel; Emmer, Adam

    2014-12-01

    This paper describes the reconstruction of the geomorphologic and landscape effects of the most catastrophic flood owing to dam failure within the territory of today's Czech Republic, namely, the Bílá Desná dam failure of 1916. Because of the realisation of the significant later transformation of the Bílá Desná river catchment almost 100 years after the flood event, the field research performed during the summer and fall of 2013 had to be supported by extensive research in regional archives for documentary data. Various data types and sources (such as court investigation notes, investigation reports for insurance companies, old maps, and old photos, as well as video and recorded testimonies of survivors) were used to reconstruct the magnitude (discharge, flood wave extent) of the flood and its effects on the channel morphology and landscape. According to the reconstruction of the dam failure, which was caused by the internal erosion of the dam, the calculated peak discharge ranged between 418.2 and 1491.7 m3s- 1 and therefore exceeded the mean flow rate of the Bílá Desná River by more than 850 times. The river channel immediately upstream and downstream of the dam reclaimed its former meandering pattern with higher sinuosity, and new gravel point bars and irregular bars have been formed. Moreover, the river channel immediately below the dam shifted by up to 30 m following the flood wave. The most significant flood impacts were apparent in the village of Desná, where the flood wave, together with transported boulders (up to 2 m in diametre) and logs from sawmills situated upstream, killed 62 inhabitants and damaged or destroyed 101 buildings. The reconstructed flood wave in the towns of Desná and Tanvald exceeded the bankfull water level twice, with a width ranging between ~ 50 and 250 m in contrast to the average channel width of a few metres.

  15. Application of electrical resistivity imaging (ERI) to a tailings dam project for artisanal and small-scale gold mining in Zaruma-Portovelo, Ecuador

    NASA Astrophysics Data System (ADS)

    Zarroca, Mario; Linares, Rogelio; Velásquez-López, Patricio C.; Roqué, Carles; Rodríguez, Roberto

    2015-02-01

    Thanks to advances in geoelectrical resistivity method over the past two decades, researchers can now gather massive geophysical data sets encompassing long distances and depths, at reasonable cost. The enhanced resolution and spatial coverage of these techniques make them, now, very attractive for use in geological engineering applications, an area for which they were previously charged to be unsuitable. The study shows the capability of electrical resistivity imaging (ERI) to identify key subsoil features that might affect a future tailings dam slated for construction at the Zaruma-Portovelo Mining District, Ecuador. The ERI profiles were gathered and processed with the aim of obtaining resistivity images of a sufficiently resolution for geotechnical use. A geophysical model was created based on these images. The resistivity images were calibrated according to geomorphological, hydrogeological and geotechnical data in order to translate geophysical information into rational geological information. The ERI results, supported by the geomorphological and geotechnical work, suggested that the rock massif is composed of weathering horizons of different rock qualities, slopes are affected by sliding surfaces and these features exert a control on the groundwater flow. These results indicated that the original site selected to construct the dam dike was susceptible to land sliding and an alternative construction site was suggested. Based on the same results, a geomorphological-hydrogeological conceptual model for layered weathered granitic massif in mountainous areas was also proposed.

  16. Characteristics of chemical weathering and water-rock interaction in Lake Nyos dam (Cameroon): Implications for vulnerability to failure and re-enforcement

    NASA Astrophysics Data System (ADS)

    Fantong, Wilson Y.; Kamtchueng, Brice T.; Yamaguchi, Kohei; Ueda, Akira; Issa; Ntchantcho, Romaric; Wirmvem, Mengnjo J.; Kusakabe, Minoru; Ohba, Takeshi; Zhang, Jing; Aka, Festus T.; Tanyileke, Gregory; Hell, Joseph V.

    2015-01-01

    For the first time, comprehensive study of hydrogeochemistry of water seeps, role of chemical weathering on dam failure, estimation of minimum width of dam to resist failure and simulation of changes in dissolved ions and secondary mineral was conducted on the Lake Nyos dam. The salient results and conclusions were; the dam spring water represented a mixture of 60-70% rainwater and 30-40% Lake water (from 0 to -40 m). The chemistry of the observed waters was Ca-HCO3 for rainwater, Ca-Mg-HCO3 in boreholes, and Mg-Ca-HCO3- for spring water. The relative rate at which ions dissolved in water was HCO3- > Mg2+ > Ca2+ > Na+ > SiO2 > K+ > NO3- > SO42- > Cl-. Weathering of rocks resulted in the formation of clay minerals such as kaolinite and smectite. Relative mobility of elements compared to Alumina (Al2O3) indicated that in monzonites there was a loss of CaO, Na2O, K2O, P2O5 and gain of SiO2, Fe2O3, TiO2, MnO and MgO, while in basalts there was a loss of SiO2, Fe2O3, Ca2O, NaO, MgO and gain of TiO2, K2O and P2O5. Values of chemical alteration index that ranged from 49 to 82 suggest a weak to intermediate categories of chemical weathering that occurred at a rate of 5.7 mm/year. Paired to that rate, which suggests that the dam is not vulnerable to failure at the previously thought time scale, some other processes (physical weathering, secondary mineral formation and lake overflow) can cause instant failure. Hydrostatic pressure of 1.6 GN generated by Lake water can be supported only when the width of the dam is greater than 19 m. PHREEQC-based simulation for 10 years indicates decoupling of Ca and Mg, and Na and Mg. Multidisciplinary monitoring of the dam is advocated.

  17. PERSPECTIVE ON LANDSLIDE DAMS.

    USGS Publications Warehouse

    Schuster, Robert L.; Costa, John E.

    1986-01-01

    The most common types of mass movements that form landslide dams are rock and soil slumps and slides; mud, debris, and earth flows: and rock and debris avalanches. The most common initiation mechanisms for dam-forming landslides are excessive rainfall and snow melt, and earthquakes. Most landslide dams are remarkable short-lived. In a sample of 63 documented cases, 22 percent of the landslide dams failed in less than 1 day after formation, and half failed within 10 days. Overtopping was by far the most frequent cause of landslide-dam failure. Backwater flooding behind landslide dams can inundate communities and valuable agricultural land. Floods from the failure of landslide dams are smaller than floods from constructed dams impounding bodies of water with the same potential energy, but larger than floods from failure of ice dams. Secondary effects of landslide-dam failures include additional landslides as reservoir levels drop rapidly, aggradation of valleys upstream and downstream of the dams, and avulsive channel changes downstream.

  18. Accidental Water Pollution Risk Analysis of Mine Tailings Ponds in Guanting Reservoir Watershed, Zhangjiakou City, China

    PubMed Central

    Liu, Renzhi; Liu, Jing; Zhang, Zhijiao; Borthwick, Alistair; Zhang, Ke

    2015-01-01

    Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA), designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the “source-pathway-target” in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing) in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River). Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method. PMID:26633450

  19. Accidental Water Pollution Risk Analysis of Mine Tailings Ponds in Guanting Reservoir Watershed, Zhangjiakou City, China.

    PubMed

    Liu, Renzhi; Liu, Jing; Zhang, Zhijiao; Borthwick, Alistair; Zhang, Ke

    2015-01-01

    Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA), designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the "source-pathway-target" in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing) in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River). Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method. PMID:26633450

  20. Debris flows from failures Neoglacial-age moraine dams in the Three Sisters and Mount Jefferson wilderness areas, Oregon

    USGS Publications Warehouse

    O'Connor, J. E.; Hardison, J.H.; Costa, J.E.

    2001-01-01

    The highest concentration of lakes dammed by Neoglacial moraines in the conterminous United States is in the Mount Jefferson and Three Sisters Wilderness Areas in central Oregon. Between 1930 and 1980, breakouts of these lakes have resulted in 11 debris flows. The settings and sequences of events leading to breaching and the downstream flow behavior of the resulting debris flows provide guidance on the likelihood and magnitude of future lake breakouts and debris flows.

  1. Debris flow from 2012 failure of moraine-dammed lake, Three Fingered Jack volcano, Mount Jefferson Wilderness, Oregon

    USGS Publications Warehouse

    Sherrod, David R.; Wills, Barton B.

    2014-01-01

    The Three Fingered Jack debris flow is one of several that have issued from moraine-dammed lakes in the Oregon Cascade Range. A thorough summary of those lakes and the hazards associated with them was published in 2001, based largely on fieldwork by Jim O’Connor and Jasper Hardison in the early 1990s. Described here are details of the 2012 event, an update to the O’Connor story begun earlier.

  2. The 26 May 1982 breakout flows derived from failure of a volcanic dam at El Chichón, Chiapas, Mexico

    USGS Publications Warehouse

    Macias, J.L.; Capra, L.; Scott, K.M.; Espindola, J.M.; Garcia-Palomo, A.; Costa, J.E.

    2004-01-01

    The eruptions of El Chicho??n between 28 March and 4 April 1982 produced a variety of pyroclastic deposits. The climactic phase, on 3 April at 07:35 (4 April at 01:35 GMT), destroyed the central andesitic dome and fed pyroclastic surges and flows that dammed nearby drainages, including the Magdalena River. By late April, a lake had formed, 4 km long and 300-400 m wide, containing a volume of 26 ?? 106 m3 of hot water. At 01:30 on 26 May, the pyroclastic dam was breached and surges of sediment and hot water soon inundated the town of Ostuaca??n, 10 km downstream. This hot flood was finally contained at Pen??itas Hydroelectric Dam, 35 km downstream, where one fatality occurred and three workers were badly scalded. Stratigraphic and sedimentologic evidence indicates that the rapidly draining lake initially discharged two debris flows, followed by five smaller debris flows and water surges. The main debris flows became diluted with distance, and by the time they reached Ostuaca??n, they merged into a single hyperconcentrated flow with a sediment concentration of ???30 vol%. Deposits from this hyperconcentrated flow were emplaced for 15 km, as far as the confluence with another river, the Mas-Pac, below which the flow was diluted to sediment-laden streamflow. The minimum volume of the breakout-flow deposits is estimated at 17 ?? 106 m3. From high-water marks, flow profiles, and simulations utilizing the DAMBRK code from the National Weather Service, we calculated a maximum peak discharge of 11,000 m3/s at the breach; this maximum peak discharge occurred 1 h after initial breaching. The calculations indicated that ???2 h were required to drain the lake.

  3. 30 CFR 57.20010 - Retaining dams.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Retaining dams. 57.20010 Section 57.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....20010 Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be...

  4. 30 CFR 57.20010 - Retaining dams.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Retaining dams. 57.20010 Section 57.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....20010 Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be...

  5. 30 CFR 57.20010 - Retaining dams.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Retaining dams. 57.20010 Section 57.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....20010 Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be...

  6. 30 CFR 57.20010 - Retaining dams.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Retaining dams. 57.20010 Section 57.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....20010 Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be...

  7. 30 CFR 56.20010 - Retaining dams.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Retaining dams. 56.20010 Section 56.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be of...

  8. 30 CFR 56.20010 - Retaining dams.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Retaining dams. 56.20010 Section 56.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be of...

  9. 30 CFR 56.20010 - Retaining dams.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Retaining dams. 56.20010 Section 56.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be of...

  10. 30 CFR 56.20010 - Retaining dams.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Retaining dams. 56.20010 Section 56.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be of...

  11. 30 CFR 56.20010 - Retaining dams.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Retaining dams. 56.20010 Section 56.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be of...

  12. 30 CFR 57.20010 - Retaining dams.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Retaining dams. 57.20010 Section 57.20010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....20010 Retaining dams. If failure of a water or silt retaining dam will create a hazard, it shall be...

  13. 75 FR 49429 - Metal and Nonmetal Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ...30 CFR Parts 56 and 57 RIN 1219-AB70 Metal and Nonmetal Dams AGENCY: Mine Safety...SUMMARY: Dam failures at metal and nonmetal mines have exposed miners...Administration (MSHA) is reviewing its existing metal and nonmetal standards for dams. The...

  14. Minimizing losses from an earthen dam breach

    SciTech Connect

    Singh, K.P. )

    1991-06-01

    The prospect of a dam breach is universally feared by dam owners. In many cases, a failure would lead to water rising many feet above the 100-yr flood plain downstream, with the likelihood of life and property losses. The state of Illinois has identified four important parameters involved in dam breach. By recognizing and analyzing the roles played by these parameters at a specific dam site, engineers can do a better job of designing and constructing a new earthen dam, or rehabilitating and then operating and maintaining an existing structure to reduce the magnitude of flooding and the resulting losses in case of a dam breach.

  15. 76 FR 34799 - Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ...cause water to go over the top of some dams even with the floodgates wide open, possibly causing dam failure. Failure of any dam would result in loss of stored water for navigation, impacts to fish and wildlife resources, loss of...

  16. Numerical modelling dam break analysis for water supply project

    NASA Astrophysics Data System (ADS)

    Lariyah, M. S.; Vikneswaran, M.; Hidayah, B.; Muda, Z. C.; Thiruchelvam, S.; Abd Isham, A. K.; Rohani, H.

    2013-06-01

    Dam provides many benefits to the society, but it can also cause extensive damage to downstream area when it fails. Dam failure can cause extensive damage to properties and loss of human life due to short warning time available. In general, dam spillway was designed to drain the maximum discharge from the dam during the Probable Maximum Flood (PMF). The spillway is functioned to prevent the dam from failure due to overtopping, which can lead to the dam failure. Dam failure will result in large volume of water travelling at very high velocity to the downstream area of the dam. It can cause extensive property damage, destruction of important facilities, and significant loss of human life along the way. Due to the potential of high hazard it poses to the downstream area, a dam break analysis is considered very essential. This paper focuses into the dam failure analysis for Kahang Dam by prediction of breach flow hydrographs and generation of inundation map at downstream area. From the PMF scenario simulation, the maximum inflow is 525.12 m3/s and peak discharge from the dam during dam failure is 6188m3/s. The results are able to provide information for preparation of Emergency Response Plan (PMF), in which appropriate steps can be taken by relevant authorities to avoid significant loss of human lives.

  17. 14. Credit PED. Downstream elevation, near completion, showing tail race ...

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

    14. Credit PED. Downstream elevation, near completion, showing tail race and trestle used to carry excavated rock and construction materials across tail race. Photo c. 1909. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  18. Twin-tailed fail-over for fileservers maintaining full performance in the presence of a failure

    DOEpatents

    Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY)

    2008-02-12

    A method for maintaining full performance of a file system in the presence of a failure is provided. The file system having N storage devices, where N is an integer greater than zero and N primary file servers where each file server is operatively connected to a corresponding storage device for accessing files therein. The file system further having a secondary file server operatively connected to at least one of the N storage devices. The method including: switching the connection of one of the N storage devices to the secondary file server upon a failure of one of the N primary file servers; and switching the connections of one or more of the remaining storage devices to a primary file server other than the failed file server as necessary so as to prevent a loss in performance and to provide each storage device with an operating file server.

  19. 106. DAM EARTH DIKE SUBMERSIBLE DAMS & DIKE ...

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

    106. DAM - EARTH DIKE - SUBMERSIBLE DAMS & DIKE CONN. AT MOVABLE DAM (ML-8-52/2-FS) March 1940 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 8, On Mississippi River near Houston County, MN, Genoa, Vernon County, WI

  20. Reliablity analysis of gravity dams by response surface method

    NASA Astrophysics Data System (ADS)

    Humar, Nina; Kryžanowski, Andrej; Brilly, Mitja; Schnabl, Simon

    2013-04-01

    A dam failure is one of the most important problems in dam industry. Since the mechanical behavior of dams is usually a complex phenomenon existing classical mathematical models are generally insufficient to adequately predict the dam failure and thus the safety of dams. Therefore, numerical reliability methods are often used to model such a complex mechanical phenomena. Thus, the main purpose of the present paper is to present the response surface method as a powerful mathematical tool used to study and foresee the dam safety considering a set of collected monitoring data. The derived mathematical model is applied to a case study, the Moste dam, which is the highest concrete gravity dam in Slovenia. Based on the derived model, the ambient/state variables are correlated with the dam deformation in order to gain a forecasting tool able to define the critical thresholds for dam management.

  1. Preliminary estimate of possible flood elevations in the Columbia River at Trojan Nuclear Power Plant due to failure of debris dam blocking Spirit Lake, Washington

    USGS Publications Warehouse

    Kresch, D.L.; Laenen, Antonius

    1984-01-01

    Failure of the debris dam, blocking the outflow of Spirit Lake near Mount St. Helens, could result in a mudflow down the Toutle and Cowlitz Rivers into the Columbia River. Flood elevations at the Trojan Nuclear Power Plant on the Columbia River, 5 mi upstream from the Cowlitz River, were simulated with a hydraulic routing model. The simulations are made for four Columbia River discharges in each of two scenarios, one in which Columbia River floods coincide with a mudflow and the other in which Columbia River floods follow a mudflow sediment deposit upstream from the Cowlitz River. In the first scenario, Manning 's roughness coefficients for clear water and for mudflow in the Columbia River are used; in the second scenario only clear water coefficients are used. The grade elevation at the power plant is 45 ft above sea level. The simulated elevations exceed 44 ft if the mudflow coincides with a Columbia River discharge that has a recurrence interval greater than 10 years (610,000 cu ft/sec); the mudflow is assumed to extend downstream from the Cowlitz River to the mouth of the Columbia River, and Manning 's roughness coefficients for a mudflow are used. The simulated elevation is 32 ft if the mudflow coincides with a 100-yr flood (820,000 cu ft/sec) and clear-water Manning 's coefficients are used throughout the entire reach of the Columbia River. The elevations exceed 45 ft if a flow exceeding the 2-yr peak discharge in the Columbia River (410,000 cu ft/sec) follows the deposit of 0.5 billion cu yd of mudflow sediment upstream of the Cowlitz River before there has been any appreciable scour or dredging of the deposit. In this simulation it is assumed that: (1) the top of the sediment deposited in the Columbia River is at an elevation of 30 ft at the mouth of the Cowlitz River, (2) the surface elevation of the sediment deposit decreases in an upstream direction at a rate of 2.5 ft/mi, and (3) clear water Manning 's coefficients apply to the entire modeled reach of the Columbia River. (Author 's abstract)

  2. A proactive approach to sustainable management of mine tailings

    NASA Astrophysics Data System (ADS)

    Edraki, Mansour; Baumgartl, Thomas

    2015-04-01

    The reactive strategies to manage mine tailings i.e. containment of slurries of tailings in tailings storage facilities (TSF's) and remediation of tailings solids or tailings seepage water after the decommissioning of those facilities, can be technically inefficient to eliminate environmental risks (e.g. prevent dispersion of contaminants and catastrophic dam wall failures), pose a long term economic burden for companies, governments and society after mine closure, and often fail to meet community expectations. Most preventive environmental management practices promote proactive integrated approaches to waste management whereby the source of environmental issues are identified to help make a more informed decisions. They often use life cycle assessment to find the "hot spots" of environmental burdens. This kind of approach is often based on generic data and has rarely been used for tailings. Besides, life cycle assessments are less useful for designing operations or simulating changes in the process and consequent environmental outcomes. It is evident that an integrated approach for tailings research linked to better processing options is needed. A literature review revealed that there are only few examples of integrated approaches. The aim of this project is to develop new tailings management models by streamlining orebody characterization, process optimization and rehabilitation. The approach is based on continuous fingerprinting of geochemical processes from orebody to tailings storage facility, and benchmark the success of such proactive initiatives by evidence of no impacts and no future projected impacts on receiving environments. We present an approach for developing such a framework and preliminary results from a case study where combined grinding and flotation models developed using geometallurgical data from the orebody were constructed to predict the properties of tailings produced under various processing scenarios. The modelling scenarios based on the case study data provide the capacity to predict the composition of tailings and the resulting environmental management implications. For example, the type and content of clay minerals in tailings will affect the geotechnical stability and water recovery. Clay content will also influence decisions made for paste or thickened tailings and underground backfilling. It is possible by using an integrated assessment framework to evaluate more alternatives, including the production of additional saleable and benign streams, alternative tailings treatment and disposal, as well as options for reuse, recycling and pre-processing of existing tailings.

  3. Peak outflow from a breached embankment dam

    USGS Publications Warehouse

    Froehlich, David C.

    1989-01-01

    A relation for rapidly predicting the peak outflow rate from a breached embankment dam has been presented. The prediction equation is based on reliable data from 19 embankment dam failures and requires as input the volume of water in the reservoir at the time a breach begins to form, and the estimated height of the final breach. Peak outflow predicted by the equation can be used with simplified flood routing procedures to determine peak flows at locations downstream of a dam. Use of the prediction equation will improve the accuracy of rapid assessments of damage that would be caused by the flood resulting from an embankment dam failure.

  4. EMBANKMENT-DAM BREACH PARAMETERS.

    USGS Publications Warehouse

    Froehlich, David C.

    1987-01-01

    The study used data from 43 embankment-dam failures to develop equations that predict breach formation model parameters. These data include the failure mode, embankment characteristics, reservoir conditions at the time of failure, geometry of the final breach, and the time taken to form the breach. Regression equations were developed to predict (1) the average width of a trapezoidal breach, (2) the average side-slope factor of a trapezoidal breach, and (3) the breach formation time.

  5. Garrison Dam

    USGS Multimedia Gallery

    Missouri River flowing through the regulation tubes and the hydroelectric power plant at Garrison Dam between Riverdale and Pick City, North Dakota. Photo taken by USGS personnel on a Civil Air Patrol flight....

  6. Q00906010024 rock check dam

    E-print Network

    00906010024 rock check dam Q00906010025 rock check dam Q00906010021 rock check dam Q00906010022 rock check dam Q00906010027 rock check dam Q00906010026 rock check dam Q00906010018 rock check dam Q00906010023 rock check dam Q00906010011 rock check dam Q00906010008 rock check dam Q00906010007 rock check dam Q

  7. Submarine and deep-sea mine tailing placements: A review of current practices, environmental issues, natural analogs and knowledge gaps in Norway and internationally.

    PubMed

    Ramirez-Llodra, Eva; Trannum, Hilde C; Evenset, Anita; Levin, Lisa A; Andersson, Malin; Finne, Tor Erik; Hilario, Ana; Flem, Belinda; Christensen, Guttorm; Schaanning, Morten; Vanreusel, Ann

    2015-08-15

    The mining sector is growing in parallel with societal demands for minerals. One of the most important environmental issues and economic burdens of industrial mining on land is the safe storage of the vast amounts of waste produced. Traditionally, tailings have been stored in land dams, but the lack of land availability, potential risk of dam failure and topography in coastal areas in certain countries results in increasing disposal of tailings into marine systems. This review describes the different submarine tailing disposal methods used in the world in general and in Norway in particular, their impact on the environment (e.g. hyper-sedimentation, toxicity, processes related to changes in grain shape and size, turbidity), current legislation and need for future research. Understanding these impacts on the habitat and biota is essential to assess potential ecosystem changes and to develop best available techniques and robust management plans. PMID:26045197

  8. 75 FR 49429 - Metal and Nonmetal Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ..., processing minerals, treating or supplying water, and controlling run- off and sediment. Although many of... 100-foot high dam at a limestone mine in Puerto Rico released over 10 million gallons of water and... slope failure in 1987, the mine operator installed instruments in the dam to monitor internal...

  9. Outbursts of landslide dammed lakes - mapping their potential across the Himalaya

    NASA Astrophysics Data System (ADS)

    Schwanghart, Wolfgang; Blöthe, Jan; Andermann, Christoff; Korup, Oliver

    2013-04-01

    Lake formation as a result of river damming by landslides is frequently observed in the Himalayas. Historic records are riddled with sudden failures of debris dams that culminated in catastrophic outburst floods and debris flows with far-reaching devastating consequences for downstream communities and infrastructure. In addition, it has been argued that the formation of large orogens is tightly coupled with the damming of these lakes as they trap sediments and abate river incision. The severity of outburst floods of landslide dammed lakes is directly related to the impounded water volume and downstream channel morphology both of which are controlled by topography. Prime insights into the spatial patterns of hazards generated by landslide dammed lakes can thus be inferred from digital elevation models (DEMs) that are available at sufficient detail at even the remotest localities. Here we quantify from topographic constraints the physically possible size range of catastrophic outburst events at the mountain-belt scale. By manipulating digital topographic, climatic, and river discharge data we estimate to first order the potential peak discharge arising from failure of hypothetical dams occurring anywhere throughout the Himalayan drainage network. Thus modelled peak discharges encompass four to six orders of magnitude, with the most extreme events surpassing the largest documented monsoon floods by a factor of >100. For a range of pre-defined breach rates, the heavy-tailed size distribution of peak discharge stretches with increasing dam height. Our simulation predicts the highest peak discharge for dam breaks outside of the Higher Himalaya, i.e. along the margins of the Tibetan Plateau, and the large orogen-parallel rivers of the Sub-Himalaya. Many of the bedrock rivers slicing through the Higher Himalaya are simply too steep to allow for trapping large quantities of water behind natural dams. This regional consistent pattern underscores the notion that high transient stream power associated with episodic natural dam breaks may play a dominant role in enhancing fluvial bedrock incision in the Higher Himalayas. From a hazard management perspective our data provide a promising and proactive tool for rapidly assessing the likely impacts of outburst events anywhere in the Himalayas.

  10. WinDAM C earthern embankment internal erosion analysis software

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA has partnered with landowners to build rural flood control dams. Overtopping and internal erosion are the causes of most dam failures. To estimate the peak discharge associated with a dam incident, the USDA-NRCS, -ARS, and Kansas State University have collaboratively developed software. ...

  11. Undamning dams

    SciTech Connect

    Crossman, J.S.

    1998-12-31

    On October 18, 1997, Vice President Gore introduced a major new initiative, the Clean Water Action Plan, commemorating the 25th anniversary of the Clean Water Act. The action plan was designed to fulfill the promise of the Clean Water Act that all US waterways would one day be fishable and swimmable. The success of the Clean Water Act in cleaning up pollution from industrial, commercial, and municipal discharges is undisputed, but the promise of fishable, swimmable waters remains unfulfilled. Nutrients, bacteria, sediment, and toxic chemicals continue to pollute the nation`s waterways from diffuse sources such as animal feedlots, storm-water runoff, agricultural drainage, and soil erosion. It is these latter sources of pollution that the Clean Water Action Plan is expected to remedy. Throughout the history of dam building, water quality has been virtually ignored. In fact, the present impact of dams on water quality is often overlooked. On the positive side, dams and their reservoirs tend to serve as settling basins. These positive benefits, however, can be offset by the negative effects dam operations have on water quality.

  12. 11. VIEW OF THE ROAD TO SEDIMENT DAM LOOKING FROM ...

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

    11. VIEW OF THE ROAD TO SEDIMENT DAM LOOKING FROM EDGE OF TAILINGS. WATER PUMP (FEATURE B-25) IS VISIBLE IN CENTER LEFT OF FRAME. - Nevada Lucky Tiger Mill & Mine, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  13. Factors affecting the failure of copper connectors brazed to copper bus bar segments on a 615-MVA hydroelectric generator at Grand Coulee Dam

    SciTech Connect

    Atteridge, D.G.; Klein, R.F.; Layne, R.; Anderson, W.E.; Correy, T.B.

    1988-01-01

    On March 21, 1986, the United States Bureau of Reclamation experienced a ground fault in the main parallel ring assembly of Unit G19 - a 615-MVA hydroelectric generator - at Grand Coulee Dam, Washington. Inspection of the unit revealed that the ground fault had been induced by fracture of one or more of the copper connectors used to join adjacent segments of one of the bus bars in the north half of the assembly. Various experimental techniques were used to detect and determine the presence of cracks, crack morphology, corrosion products, and material microstructure and/or embrittlement. The results of these inspections and recommendations are given. 7 refs., 27 figs.

  14. Institute for Water Resources, US Army Corps of Engineers Australian National Committee on Large Dams

    E-print Network

    Bowles, David S.

    of the day and for different dam breach flooding scenarios. Second, the Uncertainty Mode represents input Committee on Large Dams LIFESim: A Model for Estimating Dam Failure Life Loss DRAFT by Maged A. Aboelata and David S. Bowles Institute for Dam Safety Risk Management Utah State University Logan, Utah 2005 #12;ii

  15. V00306010057 rock check dam

    E-print Network

    ¬« ¬« ¬« ¬« ¬« XY! 16-020 16-030(c) 16-026(l) 16-028(c) 16-026(l) V00306010057 rock check dam V00306010012 rock check dam V00306010040 rock check dam V00306010039 rock check dam V00306010058 rock check dam V00306010064 rock check dam V00306010061 rock check dam V00306010062 rock check dam V00306010063

  16. Enhancing the safety of tailings management facilities

    SciTech Connect

    Meggyes, T.; Niederleithinger, E.; Witt, K.J.; Csovari, M.; Kreft-Burman, K.; Engels, J.; McDonald, C.; Roehl, K.E.

    2008-07-01

    Unsafe tailings management facilities (TMFs) have caused serious accidents in Europe threatening human health/life and the environment. While advanced design, construction and management procedures are available, their implementation requires greater emphasis. An integrated research project funded by the European Union was carried out between 2002 and 2005 with the overall goal of improving the safety of TMFs (Sustainable Improvement in Safety of Tailings Facilities - TAILSAFE, http://www.tailsafe.com/). The objective of TAILSAFE was to develop and apply methods of parameter evaluation and measurement for the assessment and improvement of the safety state of tailings facilities, with particular attention to the stability of tailings dams and slurries, the special risks inherent when such materials include toxic or hazardous wastes, and authorization and management procedures for tailings facilities. Aspects of tailings facilities design, water management and slurry transport, non-destructive and minimally intrusive testing methods, monitoring and the application of sensors, intervention and remediation options were considered in TAILSAFE. A risk reduction framework (the TAILSAFE Parameter Framework) was established to contribute to the avoidance of catastrophic accidents and hazards from tailings facilities. Tailings from the mining and primary processing of metals, minerals and coal were included within the scope of TAILSAFE. The project focused on the avoidance of hazards by developing procedures and methods for investigating and improving the stability of tailings dams and tailings bodies.

  17. V01406010015 rock check dam

    E-print Network

    XY! ¬« ¬« V01406010015 rock check dam V01406010014 rock check dam V01406010013 rock check dam 1501403010012 earthen berm V01403010008 earthen berm V01406010003 rock check dam V01406010004 rock check dam V01406010010 rock check dam V01406010011 rock check dam 15-0651 15-0307 15-0588 15-0532 15-0575 stormdrain 7160

  18. H00306010022 rock check dam

    E-print Network

    XY! H00306010022 rock check dam H00302040017 established vegetation, green hatch area 15-009(c) 15-006(c) 3M-SMA-0.5 5.57 Acres H00306010029 rock check dam H00306010021 rock check dam H00306010020 rock check dam H00306010023 rock check dam H00306010019 rock check dam H00306010024 rock check dam H

  19. V00306010057 rock check dam

    E-print Network

    XY! 16-020 16-030(c) 16-026(l) 16-028(c) 16-026(l) V00306010057 rock check dam V00306010012 rock check dam V00306010040 rock check dam V00306010039 rock check dam V00306010058 rock check dam V00306010064 rock check dam V00306010061 rock check dam V00306010062 rock check dam V00306010063 rock check dam

  20. Experimental research on the dam-break mechanisms of the Jiadanwan landslide dam triggered by the Wenchuan earthquake in China.

    PubMed

    Xu, Fu-gang; Yang, Xing-guo; Zhou, Jia-wen; Hao, Ming-hui

    2013-01-01

    Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation. PMID:23844387

  1. Experimental Research on the Dam-Break Mechanisms of the Jiadanwan Landslide Dam Triggered by the Wenchuan Earthquake in China

    PubMed Central

    Xu, Fu-gang; Yang, Xing-guo; Hao, Ming-hui

    2013-01-01

    Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation. PMID:23844387

  2. Geophysical methods for the assessment of earthen dams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dams and levees are an integral part of the fluvial system in watersheds. Their stability is of utmost concern to the Nation and to those directly impacted should failure occur. There are some 88,000 dams and 110,000 miles of levees in the USA. Many of those are earthen embankments and structures su...

  3. 49. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM ...

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

    49. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM -- DAM CONCRETE -- TYPICAL PIER ISOMETRIC. M-L 26(R) 40/1 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

  4. CRIB DAM, LOOKING ALONG DAM FROM WEST ABUTMENT, SHOWING PLANK ...

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

    CRIB DAM, LOOKING ALONG DAM FROM WEST ABUTMENT, SHOWING PLANK SHEATHING IN FOREGROUND. VIEW TO EAST - Kachess Dam, 1904 Cascade Canal Company Crib Dam, Kachess River, 1.5 miles north of Interstate 90, Easton, Kittitas County, WA

  5. 50. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM ...

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

    50. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM -- DAM CONCRETE -- GENERAL ARRANGEMENT -- SECTION AND ELEVATIONS. M-L 26(R) 40/3 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

  6. 106. Photocopied August 1978. EXTENSION OF TAIL PIT WALLS, APRIL ...

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

    106. Photocopied August 1978. EXTENSION OF TAIL PIT WALLS, APRIL 28, 1917. THE TIMBERWORK IN THE FOREGROUND WAS USED AS A COMBINATION COFFER DAM AND FORM FOR POURING THE CONCRETE TAIL RACE WALL EXTENSION. IN THE BACKGROUND ALONG THE POWER HOUSE SEVERAL COMPLETED WALL EXTENSIONS CAN BE SEEN DIMLY. (787) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  7. M01506020006 log check dam

    E-print Network

    XY! ¬« 35-0027 M01506020006 log check dam M01506020007 log check dam M01506020001 log check dam M Berm Channel/swale Check dam Sediment trap/basin Gabion Seed and mulch Cap Established vegetation SWMU

  8. M01506020006 log check dam

    E-print Network

    XY! ¬« 35-0027 M01506020006 log check dam M01506020007 log check dam M01506020001 log check dam M location Berm Channel/swale Check dam Sediment trap/basin Gabion Seed and mulch Cap Established vegetation

  9. A Structured Approach to Incorporating Uncertainty into a Dam Safety Risk David S. Bowles1

    E-print Network

    Bowles, David S.

    A Structured Approach to Incorporating Uncertainty into a Dam Safety Risk Assessment David S is presented for considering variability and knowledge uncertainties in a dam safety risk assessment of an existing dam and risk reduction alternatives: 1) Failure Event Model comprising an event tree risk model

  10. Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

    E-print Network

    Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA Cassandra R Received 6 May 2005 Availble online 7 February 2006 Abstract The failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366

  11. Coupling glacial lake impact, dam breach, and flood processes: A modeling perspective

    E-print Network

    Butler, David R. - Department of Geography, Texas State University

    Review Coupling glacial lake impact, dam breach, and flood processes: A modeling perspective impacting glacial lakes and triggering dam breaches with subsequent outburst floods. A concern models are presently available for simulating impact waves in lakes, dam failures, and flow propagation

  12. Garrison Dam and Spillway

    USGS Multimedia Gallery

    Looking to the southwest at the Garrison Dam Spillway located to the left in this picture and the Garrison Dam located to the right in this picture. Photo taken by USGS personnel on a Civil Air Patrol flight....

  13. T00706010013 rock check dam

    E-print Network

    XY! ¬« T00706010013 rock check dam T00706010014 rock check dam T00702040012 established vegetation, green hatch area T00706010002 rock check dam T00706010011 rock check dam T00703120010 rock berm T00703020003 base course berm T00706010004 rock check dam T00706010009 rock check dam T00703020008 base course

  14. T00406010008 rock check dam

    E-print Network

    XY! ¬« T00406010008 rock check dam T00406010009 rock check dam T00406010010 rock check dam T00406010011 rock check dam T-SMA-2.85 0.344 Acres 35-014(g) 35-016(n) T00406010005 rock check dam T00406010006 rock check dam T00403090004 curb T00402040007 established vegetation, green hatch area 7200 7200 7180

  15. J00206010020 rock check dam

    E-print Network

    XY! J00206010020 rock check dam J00206010023 rock check dam 09-009 09-009 09-009 PJ-SMA-2 0.901 Acres J00206010021 rock check dam J00206010019 rock check dam J00206010014 rock check dam J00203010007 Smith DATE: 14-November-2014 REVISION NUMBER: 8 XY! IP sampler location Berm Channel/swale Check dam

  16. J00206010020 rock check dam

    E-print Network

    XY! J00206010020 rock check dam J00206010027 rock check dam J00204050026 water bar J00206010028 rock check dam J00208030029 concrete cap 09-009 09-009 09-009 PJ-SMA-2 0.901 Acres J00206010021 rock check dam J00206010019 rock check dam J00206010014 rock check dam J00203010007 earthen berm J00203010009

  17. T00706010013 rock check dam

    E-print Network

    XY! ¬« T00706010013 rock check dam T00706010014 rock check dam T00702040012 established vegetation, green hatch area T00706010002 rock check dam T00706010011 rock check dam T00703120010 rock berm T00703020003 base course berm T00706010004 rock check dam T00706010009 rock check dam T00703010008 earthen berm

  18. Hoover Dam Learning Packet.

    ERIC Educational Resources Information Center

    Bureau of Reclamation (Dept. of Interior), Washington, DC.

    This learning packet provides background information about Hoover Dam (Nevada) and the surrounding area. Since the dam was built at the height of the Depression in 1931, people came from all over the country to work on it. Because of Hoover Dam, the Colorado River was controlled for the first time in history and farmers in Nevada, California, and…

  19. Glen Canyon Dam

    USGS Multimedia Gallery

    The Glen Canyon Dam on the Colorado River in Arizona. At noon Monday, Nov. 19, U.S. Interior Secretary Ken Salazar will open the dam’s river outlet tubes, releasing controlled flows larger than the usual 8,000-25,000 cubic feet per second that flows through the turbines of the Glen...

  20. Tail Buffeting

    NASA Technical Reports Server (NTRS)

    Abdrashitov, G.

    1943-01-01

    An approximate theory of buffeting is here presented, based on the assumption of harmonic disturbing forces. Two cases of buffeting are considered: namely, for a tail angle of attack greater and less than the stalling angle, respectively. On the basis of the tests conducted and the results of foreign investigators, a general analysis is given of the nature of the forced vibrations the possible load limits on the tail, and the methods of elimination of buffeting.

  1. Stability analysis of White Oak Dam

    SciTech Connect

    1995-04-11

    White Oak Dam is located in the White Oak Creek watershed which provides the primary surface drainage for Oak Ridge National Laboratory. A stability analysis was made on the dam by Syed Ahmed in January 1994 which included an evaluation of the liquefaction potential of the embankment and foundation. This report evaluates the stability of the dam and includes comments on the report prepared by Ahmed. Slope stability analyses were performed on the dam and included cases for sudden drawdown, steady seepage, partial pool and earthquake. Results of the stability analyses indicate that the dam is stable and failure of the structure would not occur for the cases considered. The report prepared by Ahmed leads to the same conclusions as stated above. Review of the report finds that it is complete, well documented and conservative in its selection of soil parameters. The evaluation of the liquefaction potential is also complete and this report is in agreement with the findings that the dam and foundation are not susceptible to liquefaction.

  2. 16. Parker Dam, only top fourth of dam visible, at ...

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

    16. Parker Dam, only top fourth of dam visible, at 320' high, Parker Dam is one of the highest in the world. Much of this height is because dam penetrates well below river bottom to fasten to bedrock. - Parker Dam, Spanning Colorado River between AZ & CA, Parker, La Paz County, AZ

  3. Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals.

    PubMed

    Schmitz, Denine; Blank, Matt; Ammondt, Selita; Patten, Duncan T

    2009-07-01

    The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated downstream geomorphic and vegetation responses to a dam failure (Pattengail Dam in 1927) and a controlled dam breach, which used natural sediment removal (Mystic Lake Dam in 1985). Our data showed vegetation responses indicative of channel and floodplain evolution at Pattengail. The size of the flood following the Pattengail dam failure initiated a series of channel adjustments and reworked over 19ha of floodplain downstream of the dam. In Mystic, we observed few flood stage indicators and a slight response in floodplain vegetation. We made several findings. (1) Dam removal effects on channel evolution and floodplain development depend on reach types and their responsiveness to flow regime change. (2) Ecologic response to dam removal depends on the sizes and timing of high flow events during and following removal. (3) Paleohydrology can be used to assess historic floods (>20 years). We see the utility of assessing the ecological responsiveness of a system to previous fluvial events or changes in flow regime. Informed about the character of a system based on its history, dam removal scientists can use these tools to set realistic restoration goals for removing a dam. PMID:19042079

  4. E00406010014 rock check dam

    E-print Network

    XY! E00406010014 rock check dam E00406010013 rock check dam E00403140016 coir log E00406010009 rock check dam E00406010010 rock check dam E00403010006 earthen berm E00404060012 rip rap E00403010015 Twomile Canyon Pajari toCan yo n XY! IP sampler location Berm Channel/swale Check dam Sediment trap

  5. 9. Excavation work at Pleasant Dam (now called Waddell Dam). ...

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

    9. Excavation work at Pleasant Dam (now called Waddell Dam). Photographer unknown, July, 22, 1926. Source: Maricopa County Municipal Water Conservation District Number One (MWD). - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  6. DETERMINING THE ERODIBILITY OF COMPACTED SOILS FOR EMBANKMENT DAMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Embankment overtopping is one of the main causes of failures and incidents in embankment dams and levees. The erosion of the embankment soil material plays a key role in both the process and rate of failure. A battery of jet erosion tests were conducted on laboratory compacted samples of two soils...

  7. Fish Assemblage Response to a Small Dam Removal in the Eightmile River System, Connecticut, USA

    NASA Astrophysics Data System (ADS)

    Poulos, Helen M.; Miller, Kate E.; Kraczkowski, Michelle L.; Welchel, Adam W.; Heineman, Ross; Chernoff, Barry

    2014-11-01

    We examined the effects of the Zemko Dam removal on the Eightmile River system in Salem, Connecticut, USA. The objective of this research was to quantify spatiotemporal variation in fish community composition in response to small dam removal. We sampled fish abundance over a 6-year period (2005-2010) to quantify changes in fish assemblages prior to dam removal, during drawdown, and for three years following dam removal. Fish population dynamics were examined above the dam, below the dam, and at two reference sites by indicator species analysis, mixed models, non-metric multidimensional scaling, and analysis of similarity. We observed significant shifts in fish relative abundance over time in response to dam removal. Changes in fish species composition were variable, and they occurred within 1 year of drawdown. A complete shift from lentic to lotic fishes failed to occur within 3 years after the dam was removed. However, we did observe increases in fluvial and transition (i.e., pool head, pool tail, or run) specialist fishes both upstream and downstream from the former dam site. Our results demonstrate the importance of dam removal for restoring river connectivity for fish movement. While the long-term effects of dam removal remain uncertain, we conclude that dam removals can have positive benefits on fish assemblages by enhancing river connectivity and fluvial habitat availability.

  8. Proceedings of the Australian Committee on Large Dams (ANCOLD) Annual Meeting, Jindabyne, New South Wales, Australia, November 1999

    E-print Network

    Bowles, David S.

    , assuming that embankment failure did not occur. Dam breach floods are estimated to have a peak flow rateProceedings of the Australian Committee on Large Dams (ANCOLD) Annual Meeting, Jindabyne, New South Wales, Australia, November 1999 ALAMO DAM DEMONSTRATION RISK ASSESSMENT by David S. Bowles1 , Loren R

  9. NEW ENGLAND DAMS

    EPA Science Inventory

    With the National Dam Inspection Act (P.L. 92-367) of 1972, Congress authorized the U.S. Army Corps of Engineers (USACE) to inventory dams located in the United States. The Water Resources Development Act of 1986 (P.L 99-662) authorized USACE to maintain and periodically publish...

  10. Dammed or Damned?

    ERIC Educational Resources Information Center

    Hirsch, Philip

    1988-01-01

    Summarizes issues raised at a workshop on "People and Dams" organized by the Society for Participatory Research in Asia. Objectives were to (1) understand problems created by dams for people, (2) consider forces affecting displaced populations and rehabilitation efforts, and (3) gain a perspective on popular education efforts among affected…

  11. Glen Canyon Dam

    USGS Multimedia Gallery

    The USGS Glen Canyon Adaptive Management Working Group took a trip in August from Glen Canyon Dam to Lees Ferry on Friday, August 31, 2012. This spot at Four Mile (four miles downstream from the dam) is where a lot of people fish: There were fishermen that day that claimed to have c...

  12. Maple River Dam Spillway

    USGS Multimedia Gallery

    The Maple River Dam is a pass-through dam that lets a limited amount of water flow through year round and fills the reservoir only during high flow. If the water rises high enough to fill the reservoir, water flows over the spillway shown in this photo.  Video taken at the same time is availabl...

  13. Garrison Dam and Spillway

    USGS Multimedia Gallery

    Looking northeast at the Garrison Dam in the back, Garrison Dam hydroelectric power plant, to the left, and the spillway, to the right. The sediment coming from the spillway is noticable. Photo taken by USGS personnel on a Civil Air Patrol flight....

  14. Simulating dam-breach flood scenarios of the Tangjiashan landslide dam induced by the Wenchuan Earthquake

    NASA Astrophysics Data System (ADS)

    Fan, X.; Tang, C. X.; van Westen, C. J.; Alkema, D.

    2012-10-01

    Floods from failures of landslide dams can pose a hazard to people and property downstream, which have to be rapidly assessed and mitigated in order to reduce the potential risk. The Tangjiashan landslide dam induced by the Mw = 7.9 2008 Wenchuan earthquake had impounded the largest lake in the earthquake affected area with an estimated volume of 3 × 108 m3, and the potential catastrophic dam breach posed a serious threat to more than 2.5 million people in downstream towns and Mianyang city, located 85 km downstream. Chinese authorities had to evacuate parts of the city until the Tangjiashan landslide dam was artificially breached by a spillway, and the lake was drained. We propose an integrated approach to simulate the dam-breach floods for a number of possible scenarios, to evaluate the severity of the threat to Mianyang city. Firstly, the physically-based BREACH model was applied to predict the flood hydrographs at the dam location, which were calibrated with observational data of the flood resulting from the artificial breaching. The output hydrographs from this model were inputted into the 1-D-2-D SOBEK hydrodynamic model to simulate the spatial variations in flood parameters. The simulated flood hydrograph, peak discharge and peak arrival time at the downstream towns fit the observations. Thus this approach is capable of providing reliable predictions for the decision makers to determine the mitigation plans. The sensitivity analysis of the BREACH model input parameters reveals that the average grain size, the unit weight and porosity of the dam materials are the most sensitive parameters. The variability of the dam material properties causes a large uncertainty in the estimation of the peak flood discharge and peak arrival time, but has little influence on the flood inundation area and flood depth downstream. The effect of cascading breaches of smaller dams downstream of the Tangjiashan dam was insignificant, due to their rather small volumes, which were only 2% of the volume of the Tangjiashan lake. The construction of the spillway was proven to have played a crucial role in reducing the dam-breach flood, because all the other natural breach scenarios would have caused the flooding of the downstream towns and parts of Mianyang city. However, in retrospect improvements on the spillway design and the evacuation planning would have been possible. The dam-break flood risk will be better controlled by reducing the spillway channel gradient and the porosity of the coating of the channel bottom. The experience and lessons we learned from the Tangjiashan case will contribute to improving the hazard mitigation and risk management planning of similar events in future.

  15. Hydraulics of embankment-dam breaching

    NASA Astrophysics Data System (ADS)

    Walder, J. S.; Iverson, R. M.; Logan, M.; Godt, J. W.; Solovitz, S.

    2012-12-01

    Constructed or natural earthen dams can pose hazards to downstream communities. Experiments to date on earthen-dam breaching have focused on dam geometries relevant to engineering practice. We have begun experiments with dam geometries more like those of natural dams. Water was impounded behind dams constructed at the downstream end of the USGS debris-flow flume. Dams were made of compacted, well-sorted, moist beach sand (D50=0.21 mm), 3.5 m from toe to toe, but varying in height from 0.5 to 1 m; the lower the dam, the smaller the reservoir volume and the broader the initially flat crest. Breaching was started by cutting a slot 30-40 mm wide and deep in the dam crest after filling the reservoir. Water level and pore pressure within the dam were monitored. Experiments were also recorded by an array of still- and video cameras above the flume and a submerged video camera pointed at the upstream dam face. Photogrammetric software was used to create DEMs from stereo pairs, and particle-image velocimetry was used to compute the surface-velocity field from the motion of tracers scattered on the water surface. As noted by others, breaching involves formation and migration of a knickpoint (or several). Once the knickpoint reaches the upstream dam face, it takes on an arcuate form whose continued migration we determined by measuring the onset of motion of colored markers on the dam face. The arcuate feature, which can be considered the head of the "breach channel", is nearly coincident with the transition from subcritical to supercritical flow; that is, it acts as a weir that hydraulically controls reservoir emptying. Photogenic slope failures farther downstream, although the morphologically dominant process at work, play no role at all in hydraulic control aside from rare instances in which they extend upstream so far as to perturb the weir, where the flow cross section is nearly self-similar through time. The domain downstream of the critical-flow section does influence the hydrograph in another way: the broader the initial dam crest, the longer the time before critical flow control is established. Flood duration is thus increased but peak discharge is decreased. Visual inspection and overhead videography reveal little turbidity in water pouring over the weir, implying that sediment there moves dominantly as bedload. Furthermore, underwater videography gives the overall impression that along the upstream dam face, erosion occurs without redeposition. Thus it would be a mistake to use empiricisms for equilibrium bedload transport to model erosion of the embankment. In mathematical terms, erosion rate cannot be backed out by calculating the divergence of transport rate; rather, transport rate should be regarded as the spatial integral of erosion rate. We use photogrammetry and motion of the colored markers to determine the erosion rate of the weir, and then infer shear stress at the weir by applying the van Rijn sediment-pickup function. Shear stress determined in this fashion is much less than what one calculates from the gradient of the energy head (an approach appropriate to steady flow). Shear stress inferred from the pickup-function calculation can serve as a constraint on computational fluid-dynamics models. Another constraint on such models, revealed by the underwater videography, is the upstream limit of sand movement, where bed shear stress equals the critical value for sand entrainment.

  16. 1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A ...

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

    1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A GRAVITY SECTION IS THE THIRD DAM BUILT BY SEATTLE CITY LIGHT TO PROVIDE WATER FOR GORGE POWERHOUSE AND WAS COMPLETED IN 1961, 1989. - Skagit Power Development, Gorge High Dam, On Skagit River, 2.9 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  17. S00906010006 rock check dam

    E-print Network

    XY! 53-0002 53-0890 53-1036 53-0598 53-0860 53-0056 S00906010006 rock check dam S00906010005 rock check dam S00906010007 rock check dam S00903010009 earthen berm S00903010010 earthen berm S00903120003 Channel/swale Check dam Sediment trap/basin Gabion Seed and mulch Cap Established vegetation SWMU boundary

  18. Gypsum-karst problems in constructing dams in the USA

    USGS Publications Warehouse

    Johnson, K.S.

    2008-01-01

    Gypsum is a highly soluble rock and is dissolved readily to form caves, sinkholes, disappearing streams, and other karst features that typically are also present in limestones and dolomites. Gypsum karst is widespread in the USA and has caused problems at several sites where dams were built, or where dam construction was considered. Gypsum karst is present (at least locally) in most areas where gypsum crops out, or is less than 30-60 m below the land surface. These karst features can compromise on the ability of a dam to hold water in a reservoir, and can even cause collapse of a dam. Gypsum karst in the abutments or foundation of a dam can allow water to pass through, around, or under a dam, and solution channels can enlarge quickly, once water starts flowing through such a karst system. The common procedure for controlling gypsum karst beneath the dam is a deep cut-off trench, backfilled with impermeable material, or a close-spaced grout curtain that hopefully will fill all cavities. In Oklahoma, the proposed Upper Mangum Dam was abandoned before construction, because of extensive gypsum karst in the abutments and impoundment area. Catastrophic failure of the Quail Creek Dike in southwest Utah in 1989 was due to flow of water through an undetected karstified gypsum unit beneath the earth-fill embankment. The dike was rebuilt, at a cost of US $12 million, with construction of a cut-off trench 600 m long and 25 m deep. Other dams in the USA with severe gypsum-karst leakage problems in recent years are Horsetooth and Carter Lake Dams, in Colorado, and Anchor Dam, in Wyoming. ?? 2007 Springer-Verlag.

  19. DYNAMIC BEHAVIOR OF CONCRETE GRAVITY DAM ON JOINTED ROCK FOUNDATION DURING LARGE-SCALE EARTHQUAKE

    NASA Astrophysics Data System (ADS)

    Kimata, Hiroyuki; Fujita, Yutaka; Horii, Hideyuki; Yazdani, Mahmoud

    Dynamic cracking analysis of concrete gravity dam has been carried out during large-scale earthquake, considering the progressive failure of jointed rock foundation. Firstly, in order to take into account the progressive failure of rock foundation, the constitutive law of jointed rock is assumed and its validity is evaluated by simulation analysis based on the past experimental model. Finally, dynamic cracking analysis of 100-m high dam model is performed, using the previously proposed approach with tangent stiffness-proportional damping to express the propagation behavior of crack and the constitutive law of jointed rock. The crack propagation behavior of dam body and the progressive failure of jointed rock foundation are investigated.

  20. Hoover Dam Intake Towers

    USGS Multimedia Gallery

    Hoover Dam impounds Lake Mead and provides drinking water and hydroelectric power to the surrounding area. It was constructed between 1931 and 1936. The Intake Towers are where water enters to generate electricity....

  1. 1. OVERALL VIEW OF SPILLWAY SHOWING BAFFLE WALL AND TAIL ...

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

    1. OVERALL VIEW OF SPILLWAY SHOWING BAFFLE WALL AND TAIL WATERS, WITH POWERHOUSE (MI-98-C) AND SUBSTATION (MI-98-D) AT LEFT. VIEW TO SOUTH. - Cooke Hydroelectric Plant, Spillway, Cook Dam Road at Au Sable River, Oscoda, Iosco County, MI

  2. Documented historical landslide dams from around the world

    USGS Publications Warehouse

    Costa, John E.; Schuster, Robert L.

    1991-01-01

    This data compilation consists of dBase IV1 data files of the location, date, triggering mechanism, kind, size, failure time and mechanism, breach dimensions, subsequent controls, materials, and references for 463 historical landslide dams and associated natural reservoirs that have been recorded throughout the World. The data base presented in this report is a compilation of information on the characteristics of 463 landslide dams from around the World. It forms a basis on which to assess potential threats from existing landslide dams, or newly-formed landslide dams. The data base includes only landslide dams that have formed in historical times - that is, those formed during times when humans were able to record their occurrence, and the information transferred through various means of written and/or oral documentation. There have been far more prehistoric landslide dams about which relatively little is known. None of these is included in this data base. The focus on historical landslide dams allows insights into this natural process that will aid in understanding their role as a significant geologic process in recent Earth history.

  3. Garrison Dam and Garrison Dam National Fish Hatchery

    USGS Multimedia Gallery

    The Garrison Dam National Fish Hatchery and Garrison Dam between Pick City and Riverdale, North Dakota. The Garrison Dam National Fish Hatchery is in the bottom left of the photo. Photo taken by USGS personnel on a Civil Air Patrol flight....

  4. ECHETA DAM RIPRAP ON RESERVOIR SIDE OF THE DAM AT ...

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

    ECHETA DAM RIP-RAP ON RESERVOIR SIDE OF THE DAM AT BREACH. VIEW TO NORTH-NORTHEAST. - Echeta Dam & Reservoir, 2.9 miles east of Echeta Road at Echeta Railroad Siding at County Road 293, Echeta, Campbell County, WY

  5. 32. AERIAL VIEW OF TIETON DAM, UPSTREAM FACE OF DAM ...

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

    32. AERIAL VIEW OF TIETON DAM, UPSTREAM FACE OF DAM (Trashrack-structure for outlet at lower left in reservoir, spillway at upper left. Reservoir nearly empty due to drought.) - Tieton Dam, South & East of State Highway 12, Naches, Yakima County, WA

  6. Heavy Tails Tail Density Archimedean and t Copulas Tail Densities of Vines Concluding Remarks Tail Densities of Copulas and Extremal

    E-print Network

    Li, Haijun

    Heavy Tails Tail Density Archimedean and t Copulas Tail Densities of Vines Concluding Remarks Tail of Mathematics Washington State University MMR2011, Beijing Haijun Li Tail Densities of Copulas and Extremal Dependence MMR2011, Beijing 1 / 26 #12;Heavy Tails Tail Density Archimedean and t Copulas Tail Densities

  7. Experimental Study on Cracking, Reinforcement, and Overall Stability of the Xiaowan Super-High Arch Dam

    NASA Astrophysics Data System (ADS)

    Lin, Peng; Zhou, Weiyuan; Liu, Hongyuan

    2015-03-01

    The Xiaowan super-high arch dam has faced challenging construction problems. Here, we provide a scientifically-based reference for applying geomechanical model testing to support the nonlinear design of super-high arch dams. We applied experimental similarity theory and techniques. Based on four 3D geomechanical model tests, the dam stress characteristics, deformation distribution, and the safety factors of the dam foundation were identified and compared. We also analyzed cracking characteristics of the up- and downstream dam surfaces and induced joints in the dam heel, the rock mass failure process of the dam-foundation interface, and the abutments. We propose foundation reinforcement measures for weak rock masses, alteration zones, and other faults in the abutments based on the 3D and plane tests each at a different elevation. The results show that all dam deformations remained normal with no yielding or tensile cracking under a normal water load. The reinforced rock mass increased the crack initial safety in the dam heel and toe by ~20 %. The minimum crack initial safety factor ( K 1) of the dam heel was 1.4. The induced joint in the dam heel contributed to a reduction in tensile stress at the upstream dam heel, improving K 1. Compared with similar projects following reinforcement measures, the abutment stiffness and overall stability of the Xiaowan arch dam satisfy operational requirements. Four years of monitoring operations show that key areas near the dam remained normal and the dam foundation is functioning well. Our results may also be applicable to the design and construction of similar projects worldwide.

  8. An Investigation on the Characteristics of the Seismic Signals Induced by Overtopping Dam Breach

    NASA Astrophysics Data System (ADS)

    Feng, Z.; Chen, S.; Kao, S.

    2012-12-01

    Deep-seated landslide masses often block rivers and form landslide dams. Most landslide dams are prone to failure by overtopping water and may induce strong surge wave in the downstream. This study discussed the characteristics of dam break surge wave by experimental methods. We established an artificial dam on a creek in Nantou, Taiwan, for the large-scale dam breach test by overtopping. Flume tests in laboratory were also setup to observe the stability and erosion process of model dams. Accelerometers were used to record the vibrational signals induced by the overtopped water. The vibration signals induced by the surge wave were successfully captured. The velocity of the surge wave front was calculated using the time-frequency spectral magnitude obtained from Hilbert-Huang Transform (HHT). The frequency contents of the seismic signals of the surge waves were also analyzed. The erosion process and erosion rate and duration were discussed. The characteristics including frequency range, duration and corresponding processes, of the vibration signals from the artificial dam and flume tests were compared to the analyzed characteristics of the actual landslide dam breach event at Xiaolin, Kaohsiung occurred in 2009 (Feng, 2012).; An artificial dam on a creek in Nantou, Taiwan, for the large-scale dam breach test by overtopping. ; Opening after the large-scale dam breach test by overtopping.

  9. Dam health diagnosis and evaluation

    NASA Astrophysics Data System (ADS)

    Wu, Zhongru; Su, Huaizhi

    2005-06-01

    Based on the bionics principle in the life sciences field, we regard a dam as a vital and intelligent system. A bionics model is constructed to observe, diagnose and evaluate dam health. The model is composed of a sensing system (nerve), central processing unit (cerebrum) and decision-making implement (organism). In addition, the model, index system and engineering method on dam health assessment are presented. The proposed theories and methods are applied to evaluate dynamically the health of one concrete dam.

  10. Kidney Failure

    MedlinePLUS

    ... Details» www.kidneyfund.org > Kidney Disease > Kidney Failure Kidney Failure Kidney failure is when your kidneys stop ... are the tests for kidney failure? How is kidney failure (ESRD) different from chronic kidney disease (CKD)? ...

  11. Tail gut cyst.

    PubMed

    Rao, G Mallikarjuna; Haricharan, P; Ramanujacharyulu, S; Reddy, K Lakshmi

    2002-01-01

    The tail gut is a blind extension of the hindgut into the tail fold just distal to the cloacal membrane. Remnants of this structure may form tail gut cyst. We report a 14-year-old girl with tail gut cyst that presented as acute abdomen. The patient recovered after cyst excision. PMID:12546176

  12. Risk assessment for large Romanian dams situated on Bistrita and Siret Rivers

    NASA Astrophysics Data System (ADS)

    Moldovan, Iren-Adelina; Petruta Constantin, Angela; Popescu, Emilia; Toma-Danila, Dragos; Otilia Placinta, Anica

    2015-04-01

    The work will present an ongoing national Project that have as final goal to provide the local emergency services with warnings of a potential dam failure and ensuing flood as a result of a large earthquake occurrence, allowing further public training for evacuation. Probabilistic seismic hazard (PSH), vulnerability and risk studies in 6 counties from Moldova region including Izvorul Muntelui Dam, down on Bistrita and following on Siret River and theirs affluent will be accomplished during the project. A number of 5 large dams (the most vulnerable) will be studied in detail and flooding maps will be drawn to find the most exposed downstream localities both for risk assessment studies and warnings. The results will consist in local and regional seismic information, dams specific characteristics and locations, seismic hazard maps and risk classes, for all dams sites (for more than 30 dams), inundation maps (for the most vulnerable 5 dams from the region) and possible affected localities. The maps will provide the best available estimate of the general location and extent of dam failure inundation areas and will tell if a specific location lies within a dam failure inundation zone. Besides periodical technical inspections, the monitoring and the surveillance of dams' related structures and infrastructures, there are some more seismic specific requirements towards dams' safety. The most important one is the seismic risk assessment that can be accomplished by rating the dams into seismic risk classes using the theory of Bureau and Ballentine (2002), and Bureau (2003), taking into account the maximum expected peak ground motions at the dams site. In this paper we will obtain the ground motion parameters in the dams locations using probabilistic hazard assessment techniques, the structures vulnerability and the downstream risk characteristics (human, economical, historic and cultural heritage, etc) in the areas that might be flooded in the case of a dam failure, and will compute the risk factor for the most exposed dams in the area. This work is partially supported by the Partnership in Priority Areas Program - PNII, under MEN-UEFISCDI, DARING Project no. 69/2014 and NUCLEU project, PN 09 30/2009.

  13. Wim van Dam CURRICULUM VITAE

    E-print Network

    California at Santa Barbara, University of

    Wim van Dam CURRICULUM VITAE Department of Computer Science Work: +1-805-893 5211 Harold Frank Hall in physics. #12;Curriculum Vitae Wim van Dam, June 2008 2 PUBLICATIONS Journal and Conference Articles [1] "Quantum Algorithms for Algebraic Problems", Andrew M. Childs and Wim van Dam, to appear in Reviews

  14. Elwha Dam-removal

    USGS Multimedia Gallery

    Part of the USGS Elwha River Research Team at the Dam Removal Celebration (from left to right Pat Shafroth - USGS Research Ecologist., Jon Warrick - USGS Research Geologist, Jeff Duda - USGS Research Ecologist, Guy Gelfenbaum - USGS Coastal Geologic and Oceanographic Researc...

  15. EARTH DAM OR SPILLWAY?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aging of the US water control and management infrastructure is increasing the likelihood that some dams will be overtopped during extreme floods. As structures approach their planned service life, sediment pools fill and continued sedimentation results in a reduction in the volume available for flo...

  16. Monitoring pool-tail fines

    NASA Astrophysics Data System (ADS)

    Bunte, K.; Potyondy, J. P.; Abt, S. R.; Swingle, K. W.

    2010-12-01

    Fine sediment < 2 and < 6 mm deposited in pool-tail areas of mountain streams is often measured to monitor changes in the supply of fines (e.g., by dam removal, bank erosion, or watershed effects including fires and road building) or to assess the status and trend of aquatic ecosystems. Grid counts, pebble counts, and volumetric bedmaterial samples are typically used to quantify pool-tail fines. Grid-count results exhibit a high degree of variability not only among streams and among operators, but also among crews performing a nearly identical procedure (Roper et al. 2010). Variability is even larger when diverse methods are employed, each of which quantifies fines in a different way: grid counts visually count surface fines on small patches within the pool-tail area, pebble counts pick up and tally surface particles along (riffle) transects, and volumetric samples sieve out fines from small-scale bulk samples; and even when delimited to pool-tail areas, individual methods focus on different sampling locales. Two main questions were analyzed: 1) Do pool-tail fines exhibit patterns of spatial variability and are some grid count schemes more likely to provide accurate results than others. 2) How and why does the percentage of fines vary among grid counts, pebble counts, and volumetric samples. In a field study, grids were placed at 7 locales in two rows across the wetted width of 10 pool tails in a 14-m wide 3rd order coarse gravel-bed mountain stream with <4% sand and <8% < 6 mm. Several pebble count transects were placed across each pool-tail area, and three volumetric samples were collected in each of three pool tails. Pebble and grid counts both indicated a fining trend towards one or both banks, sometimes interrupted by a secondary peak of fines within the central half of the wetted width. Among the five sampling schemes tested, grid counts covering the wetted width with 7 locales produced the highest accuracy and the least variability among the pools of the reach. Pebble counts between the two waterlines indicated 2-3 times more fines than grid counts, likely because grid counts did not extend exactly up to the waterline. However, when confined to the central 50% of the wetted width, grid counts indicated 1.2 and 1.6 times more fines < 2 and < 6 mm than pebble counts, likely because the plexiglass viewer used with grid counts improved the visibility of the bed. Volumetric armor layer samples (particles > 90 mm removed) indicated 1.4 and 1.2 times more fines < 2 and < 6 mm than grid counts at the same locales, while subarmor samples had 8-9 times more fines. In conclusion, methodological differences and the specific sampling locales selected by a method affect comparability of sampling results. Grid count accuracy and precision may be improved by extending both the width coverage and the sample size within a pool tail.

  17. CG-DAMS: Concrete gravity dam stability analysis software

    SciTech Connect

    Not Available

    1993-01-01

    CG-DAMS is a finite element based program written specifically for the stability analysis of concrete gravity dams. The code automates the prediction and evaluation of cracking in the dam, along the dam-rock interface, and in the foundation using incremental nonlinear analysis techniques based on the smeared crack'' approach. Its primary application is in the computation of dam-rock interface sliding stability factors of safety. The automated procedure for crack propagation analysis replaces the trial-and-error cracked-base analysis method commonly used in gravity dam safety analyses. This Application manual of CG-DAMS illustrates, through sample problems, the many features of the software. Example problems illustrate the capabilities of both CG-DAMS-PC and CG-DAMS-ABAQUS. CG-DAMS-PC is a menu driven program that runs on 386/486 PCs under the DOS operating system (4 Megabytes RAM, 25 Megabytes of hard disk space). CG-DAMS-ABAQUS is a pre- and post-processor along with a concrete constitutive model and distributed load module that interfaces with the ABAQUS general purpose finite element program. The PC program contains thermal analysis capabilities, a rough crack constitutive model, and an interface to the CRFLOOD software not available with the ABAQUS version. The CG-DAMS-ABAQUS program contains time marching dynamic analysis capabilities not available with the PC program. Example analyses presented include static, pseudo dynamic, and time marching dynamic analyses. The manual also presents sensitivity evaluations on mesh size and foundation material strength. Comparisons are presented between CG-DAMS and gravity method calculations. Comparisons with other finite element software are included for the dynamic time history analyses.

  18. Risk Perception Analysis Related To Existing Dams In Italy

    NASA Astrophysics Data System (ADS)

    Solimene, Pellegrino

    2013-04-01

    In the first part of this work, the progress of Italian National Rules about dams design, construction and operation are presented to highlight the strong connection existing between the promulgation of new decrees, as a consequence of a dam accidents, and the necessity to prevent further loss of lives and goods downstream. Following the Gleno Dam failure (1923), a special Ministerial Committee wrote out the first Regulations and made the proposal to establish, within the High Council of Public Works, a special department that become soon the "Dam Service", with the tasks of control and supervision about construction and operation phases of the dams and their reservoirs. A different definition of tasks and the structure of Dam Service were provided in accordance with law n° 183/1989, which transferred all the technical services to the Office of the Prime Minister; the aim was to join the Dam Office with the Department for National Technical Services, with the objective of increasing the knowledge of the territory and promoting the study on flood propagation downstream in case of operations on bottom outlet or hypothetical dam-break. In fact, population living downstream is not ready to accept any amount of risk because has not a good knowledge of the efforts of experts involved in dam safety, both from the operators and from the safety Authority. So it's important to optimize all the activities usually performed in a dam safety program and improve the emergency planning as a response to people's primary needs and feeling about safety from Civil Protection Authority. In the second part of the work, a definition of risk is provided as the relationship existing between probability of occurrence and loss, setting out the range within to plan for prevention (risk mitigation), thanks to the qualitative assessment of the minimum safety level that is suited to assign funds to plan for Civil Protection (loss mitigation). The basic meaning of the reliability of a zoned earthfill dam is illustrated by defining the risk analysis during its construction and operation. A qualitative "Event Tree Analysis" makes clear with an example the probability of occurrence of the events triggered by an earthquake, and leads to a classification of the damage level. Finally, a System Dynamics (SD) approach is presented to investigate possibilities of a preventive planning in relationship to the risk, so that it's possible to establish shared procedures to achieve the correct management in any crisis phase. As a qualitative result of a SD application, figure 1 presents a flow-chart about a case study on the same dam so to illustrate the emergency planning in a step by step procedure according to the Regulations.

  19. 1000 dams down and counting

    USGS Publications Warehouse

    O'Connor, James E.; Duda, Jeff J.; Grant, Gordon E.

    2015-01-01

    Forty years ago, the demolition of large dams was mostly fiction, notably plotted in Edward Abbey's novel The Monkey Wrench Gang. Its 1975 publication roughly coincided with the end of large-dam construction in the United States. Since then, dams have been taken down in increasing numbers as they have filled with sediment, become unsafe or inefficient, or otherwise outlived their usefulness (1) (see the figure, panel A). Last year's removals of the 64-m-high Glines Canyon Dam and the 32-m-high Elwha Dam in northwestern Washington State were among the largest yet, releasing over 10 million cubic meters of stored sediment. Published studies conducted in conjunction with about 100 U.S. dam removals and at least 26 removals outside the United States are now providing detailed insights into how rivers respond (2, 3).

  20. Geomorphic and Ecological Issues in Removal of Sediment-Filled Dams in the California Coast Ranges (Invited)

    NASA Astrophysics Data System (ADS)

    Kondolf, G. M.; Oreilly, C.

    2010-12-01

    Water-supply reservoirs in the actively eroding California Coast Ranges are vulnerable to sediment filling, thus creating obsolete impounding dams (Minear & Kondolf 2009). Once full of sediment, there is more impetus to remove dams for public safety and fish passage, but managing accumulated sediments becomes a dominant issue in dam removal planning. We analyzed the planning process and sediment management analyses for five dams, all of which have important ecological resources but whose dam removal options are constrained by potential impacts to downstream urban populations. Ringe Dam on Malibu Ck, Matilija Dam on the Ventura River, Searsville Dam on San Francisquito Ck, and Upper York Creek Dam on York Ck cut off important habitat for anadromous steelhead trout (Oncorhynchus mykiss). San Clemente Dam on the Carmel River has a working fish ladder, but only some of the migratory steelhead use it. By virtue of having filled with sediment, all five dams are at greater risk of seismic failure. San Clemente Dam is at greater risk because its foundation is on alluvium (not bedrock), and the poor-quality concrete in Matilija Dam is deteriorating from an akali-aggregate reaction. Simply removing the dams and allowing accumulated sediments to be transported downstream is not an option because all these rivers have extremely expensive houses along downstream banks and floodplains, so that allowing the downstream channel to aggrade with dam-dervied sediments could expose agencies to liability for future flood losses. Analyses of potential sediment transport have been based mostly on application of tractive force models, and have supported management responses ranging from in-situ stabilization (San Clemente and Matilija) to removal of stored sediment (York) to annual dredging to maintain capacity and prevent sediment passing over the dam (proposed for Searsville).

  1. Health impacts of large dams

    SciTech Connect

    Lerer, L.B.; Scudder, T.

    1999-03-01

    Large dams have been criticized because of their negative environmental and social impacts. Public health interest largely has focused on vector-borne diseases, such as schistosomiasis, associated with reservoirs and irrigation projects. Large dams also influence health through changes in water and food security, increases in communicable diseases, and the social disruption caused by construction and involuntary resettlement. Communities living in close proximity to large dams often do not benefit from water transfer and electricity generation revenues. A comprehensive health component is required in environmental and social impact assessments for large dam projects.

  2. Owyhee River intracanyon lava flows: does the river give a dam?

    USGS Publications Warehouse

    Ely, Lisa L.; Brossy, Cooper C.; House, P. Kyle; Safran, Elizabeth B.; O'Connor, Jim E.; Champion, Duane E.; Fenton, Cassandra R.; Bondre, Ninad R.; Orem, Caitlin A.; Grant, Gordon E.; Henry, Christopher D.; Turrin, Brent D.

    2013-01-01

    Rivers carved into uplifted plateaus are commonly disrupted by discrete events from the surrounding landscape, such as lava flows or large mass movements. These disruptions are independent of slope, basin area, or channel discharge, and can dominate aspects of valley morphology and channel behavior for many kilometers. We document and assess the effects of one type of disruptive event, lava dams, on river valley morphology and incision rates at a variety of time scales, using examples from the Owyhee River in southeastern Oregon. Six sets of basaltic lava flows entered and dammed the river canyon during two periods in the late Cenozoic ca. 2 Ma–780 ka and 250–70 ka. The dams are strongly asymmetric, with steep, blunt escarpments facing up valley and long, low slopes down valley. None of the dams shows evidence of catastrophic failure; all blocked the river and diverted water over or around the dam crest. The net effect of the dams was therefore to inhibit rather than promote incision. Once incision resumed, most of the intracanyon flows were incised relatively rapidly and therefore did not exert a lasting impact on the river valley profile over time scales >106 yr. The net long-term incision rate from the time of the oldest documented lava dam, the Bogus Rim lava dam (?1.7 Ma), to present was 0.18 mm/yr, but incision rates through or around individual lava dams were up to an order of magnitude greater. At least three lava dams (Bogus Rim, Saddle Butte, and West Crater) show evidence that incision initiated only after the impounded lakes filled completely with sediment and there was gravel transport across the dams. The most recent lava dam, formed by the West Crater lava flow around 70 ka, persisted for at least 25 k.y. before incision began, and the dam was largely removed within another 35 k.y. The time scale over which the lava dams inhibit incision is therefore directly affected by both the volume of lava forming the dam and the time required for sediment to fill the blocked valley. Variations in this primary process of incision through the lava dams could be influenced by additional independent factors such as regional uplift, drainage integration, or climate that affect the relative base level, discharge, and sediment yield within the watershed. By redirecting the river, tributaries, and subsequent lava flows to different parts of the canyon, lava dams create a distinct valley morphology of flat, broad basalt shelves capping steep cliffs of Tertiary sediment. This stratigraphy is conducive to landsliding and extends the effects of intracanyon lava flows on channel geomorphology beyond the lifetime of the dams.

  3. When Heavy-Tailed and Light-Tailed Flows Compete: The Response Time Tail Under

    E-print Network

    Nair, Jayakrishnan U.

    When Heavy-Tailed and Light-Tailed Flows Compete: The Response Time Tail Under Generalized Max tail under generalized max-weight policies in settings where the traffic flows are highly asymmetric. Specifically, we study an extreme setting with two traffic flows, one heavy-tailed, and one light-tailed

  4. Tail Density Archimedean and t Copulas Tail Densities of Vines Concluding Remarks Tail Densities of Copulas

    E-print Network

    Li, Haijun

    Tail Density Archimedean and t Copulas Tail Densities of Vines Concluding Remarks Tail Densities of Toronto, May 27 2014 Haijun Li Tail Densities of Copulas University of Toronto, May 27 2014 1 / 22 #12;Tail Density Archimedean and t Copulas Tail Densities of Vines Concluding Remarks Let X = (X1

  5. Flooding countries and destroying dams

    E-print Network

    Utrecht, Universiteit

    Flooding countries and destroying dams Rodrigo I. Silveira Ren´e van Oostrum Department-3275 #12;Flooding countries and destroying dams Rodrigo I. Silveira and Ren´e van Oostrum Department of such a technique is the one proposed by Rieger [17] and is also part of the "outlet breaching" algorithm of Martz

  6. Tubes at Glen Canyon Dam

    USGS Multimedia Gallery

    The river outlet tubes at Glen Canyon Dam on the Colorado River in Arizona. At noon Monday, Nov. 19, U.S. Interior Secretary Ken Salazar will open the dam's river outlet tubes, releasing controlled flows larger than the usual 8,000-25,000 cubic feet per second that flows through the turbines of...

  7. Geotechnical practice in dam rehabilitation

    SciTech Connect

    Anderson, L.R.

    1993-01-01

    This proceedings, Geotechnical Practice in Dam Rehabilitation, consists of papers presented at the Specialty Conference sponsored by the Geotechnical Engineering Division of the American Society of Civil Engineers held in Raleigh, North Carolina, April 25-28, 1993. The conference provided a forum for the discussion of the rehabilitation of dams, including case histories and current geotechnical practice. The topics covered by this proceeding include: (1) inspection and monitoring of dams; (2) investigation and evaluation of dams and foundations; (3) risk and reliability assessment; (4) increasing reservoir capacity, spillway modifications and overtopping; (5) seepage control; (6) improving stability of dams, foundations and reservoir slopes; (7) rehabilitation for seismic stability; and (8) geosynthetics and ground improvement techniques.

  8. History of dams at the Department of Energy`s Savannah River Site, Aiken, South Carolina

    SciTech Connect

    Jones, M.P.; Wilson, C.B.

    1995-12-01

    Since the production of nuclear material at SRS for weapons required large quantities of cooling water, a series of canals, dikes, and dams were constructed to provide conveyance systems and reservoirs. This paper presents a brief overview of the history of the construction of the dams and dikes. Attention is given to the use of asphaltic concrete for 30 years (and its maintenance and repair) to line the banks of dikes and the upstream slopes of dams to prevent erosion and possible failure. The ability of asphaltic concrete in preventing dam/dike failure was proven. Benefits and drawbacks to the use of this material are discussed based on the extensive experience at SRS.

  9. Heart Failure

    MedlinePLUS

    ... version of this page please turn Javascript on. Heart Failure What is Heart Failure? In heart failure, the heart cannot pump ... the lungs, where it picks up oxygen. The Heart's Pumping Action In normal hearts, blood vessels called ...

  10. Heart Failure

    MedlinePLUS

    MENU Return to Web version Heart Failure Overview What is heart failure? Despite the way it sounds, the term "heart failure" simply means ... you were born with) Diabetes Thyroid problems Diagnosis & Tests How will my doctor know if I have ...

  11. 6. GENE WASH DAM, LOOKING NORTHWEST. SURVEY REFLECTOR IN FOREGROUND ...

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

    6. GENE WASH DAM, LOOKING NORTHWEST. SURVEY REFLECTOR IN FOREGROUND FOR MONITORING MOVEMENT OF DAM AND EARTH. - Gene Wash Reservoir & Dam, 2 miles west of Parker Dam, Parker Dam, San Bernardino County, CA

  12. Seismic safety of earth dams: A probabilistic approach

    SciTech Connect

    Simos, N.; Costantino, C.J.; Reich, M.

    1994-08-01

    The evaluation of the potential for slope sliding and/or liquefaction failure of earthen dams subjected to earthquake loadings is most often based on deterministic procedures of both the excitation input and of the physical model. Such treatment provides answers in the form of either factor of safety values or a yes or no as to whether liquefaction will occur or not. Uncertainties in the physical properties of the soil in the embankment and the foundation layers underlying the dam are typically treated with parametric studies. Consideration of probabilities pertaining to the uncertainties of the earthquake and of the site characterization is expected to augment the prediction of failure potential by associating slope and liquefaction failure to generic properties of the earthquake and of the site characterization. In this study, the procedures for conditional slope failure/liquefaction probabilities are formulated based on a series of simulated deterministic analyses of a dam cross section . These synthetic earthquakes emanate from a 1-D stationary stochastic process of zero mean and an analytical form of power spectral density function. The response of the dam section is formed upon a dynamic finite element approach which provides the temporal variations of the stresses, strains and pore water pressure throughout the model. The constitutive response of the granular soil skeleton and its coupling with the fluid phase is formulated based on the Biot dynamic equations of motion with nonlinear terms compensated for into soil hysteretic damping. Lastly, a stochastic approach to liquefaction based on the transferring of the input motion statistics to the cross section is presented.

  13. Controls on the breach geometry and flood hydrograph during overtopping of non-cohesive earthen dams

    USGS Publications Warehouse

    Walder, Joseph S.; Iverson, Richard M.; Godt, Jonathan W.; Logan, Matthew; Solovitz, Stephen A.

    2015-01-01

    Overtopping failure of non-cohesive earthen dams was investigated in 13 large-scale experiments with dams built of compacted, damp, fine-grained sand. Breaching was initiated by cutting a notch across the dam crest and allowing water escaping from a finite upstream reservoir to form its own channel. The channel developed a stepped profile, and upstream migration of the steps, which coalesced into a headcut, led to the establishment of hydraulic control (critical flow) at the channel head, or breach crest, an arcuate erosional feature that functions hydraulically as a weir. Novel photogrammetric methods, along with underwater videography, revealed that the retreating headcut maintained a slope near the angle of friction of the sand, while the cross section at the breach crest maintained a geometrically similar shape through time. That cross-sectional shape was nearly unaffected by slope failures, contrary to the assumption in many models of dam breaching. Flood hydrographs were quite reproducible--for sets of dams ranging in height from 0.55 m to 0.98 m--when the time datum was chosen as the time that the migrating headcut intersected the breach crest. Peak discharge increased almost linearly as a function of initial dam height. Early-time variability between flood hydrographs for nominally identical dams is probably a reflection of subtle experiment-to-experiment differences in groundwater hydrology and the interaction between surface water and groundwater.

  14. Controls on the breach geometry and flood hydrograph during overtopping of noncohesive earthen dams

    NASA Astrophysics Data System (ADS)

    Walder, Joseph S.; Iverson, Richard M.; Godt, Jonathan W.; Logan, Matthew; Solovitz, Stephen A.

    2015-08-01

    Overtopping failure of noncohesive earthen dams was investigated in 13 large-scale experiments with dams built of compacted, damp, fine-grained sand. Breaching was initiated by cutting a notch across the dam crest and allowing water escaping from a finite upstream reservoir to form its own channel. The channel developed a stepped profile, and upstream migration of the steps, which coalesced into a headcut, led to the establishment of hydraulic control (critical flow) at the channel head, or breach crest, an arcuate erosional feature that functions hydraulically as a weir. Novel photogrammetric methods, along with underwater videography, revealed that the retreating headcut maintained a slope near the angle of friction of the sand, while the cross section at the breach crest maintained a geometrically similar shape through time. That cross-sectional shape was nearly unaffected by slope failures, contrary to the assumption in many models of dam breaching. Flood hydrographs were quite reproducible—for sets of dams ranging in height from 0.55 m to 0.98 m—when the time datum was chosen as the time that the migrating headcut intersected the breach crest. Peak discharge increased almost linearly as a function of initial dam height. Early-time variability between flood hydrographs for nominally identical dams is probably a reflection of subtle experiment-to-experiment differences in groundwater hydrology and the interaction between surface water and groundwater.

  15. Cracking monitoring by FBG strain sensor in the small scale dam model

    NASA Astrophysics Data System (ADS)

    Ren, Liang; Li, Hongnan; Li, Dongsheng

    2009-03-01

    Accurate measurement of strain variation and effective prediction of failure within models has been a major objective for strain sensors in dam model tests. In this paper, a FBG strain sensor with enhanced strain sensitivity and packaged by two gripper tubes is presented and applied in the seismic tests of a small scale dam model. This paper discusses the principle of enhanced sensitivity of the FBG strain sensor. Calibration experiments were conducted to evaluate the sensor's strain transferring characteristics on plates of different material. This paper also investigates the applicability of the FBG strain sensors in seismic tests of a dam model by conducting a comparison between the test measurements of FBG sensors and analytical predictions, monitoring the failure progress and predicting the cracking inside the dam model. Results of the dam model tests prove that this FBG strain sensor has the advantages of small size, high precision and embedability, demonstrate promising potential in cracking and failure monitoring and in identification of the dam model.

  16. Geomorphic responses to large check-dam removal on a mountain river in Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, H.; Stark, C. P.; Cook, K. L.; Kuo, W.

    2011-12-01

    Dam removal has become an important aspect of river restoration in recent years, but studies documenting the physical and ecological response to dam removal are still lacking - particularly in mountain rivers and following major floods. This presentation documents the recent removal of a large dam on a coarse-grained, steep (an order of magnitude greater than on the Marmot) mountain channel in Taiwan. The Chijiawan river, a tributary of the Tachia River draining a 1236 km2 watershed, is the only habitat in Taiwan of the endangered Formosan landlocked salmon. The habitat of this fish has been cut significantly since the 1960s following construction of check dams designed to prevent reservoir sedimentation downstream. The largest and lowermost barrier on Chijiawan creek is the 15m high, "No. 1 Check Dam" built in 1971. Forty years later, in early 2011, the sediment wedge behind the dam had reached an estimated 0.2 million m3 and the dam toe had been scoured about 4m below its foundation, posing a serious risk of dam failure. For these reasons, the Shei-Pa National Park removed the dam in late May 2011. To monitor the response of the river to dam removal, we installed video cameras, time-lapse cameras, stage recorders, and turbidity sensors, conducted surveys of grain size distributions and longitudinal profiles, and carried out repeat photography. Channel changes were greatest immediately following removal as a result of the high stream power, steep energy slope, and unconsolidated alluvial fill behind the dam. Headcut propagation caused immediate removal of the sand-grade sediment and progressive channel widening. One month after dam removal, a minor flood event excavated a big wedge of sediment from the impoundment. Most of the subsequent downstream deposition occurred within 500m of the dam, with alluviation reaching up to 0.5m in places. Two months after dam removal, erosion had propagated 300m upstream into the impounded sediment along a bed profile of gradient at 1.4% at a headcut with a local gradient of 5.1%. The change in grain size was a fining of the sediment at the two downstream sites and a slight coarsening at the upstream site from April 2010 to July 2011. This is likely due to the increase in energy upstream of the dam post-removal, which has transported the fine-grained sediments downstream. As the river adjusts over coming months and years, we anticipate that observations such as these will help generate an important resource for all those concerned with dam removal and river restoration.

  17. Is it worth a dam?

    PubMed Central

    Joyce, S

    1997-01-01

    Once a sign of modernization and growth, dams are often seen today as symbols of environmental and social devastation. Over 800,000 dams have been built worldwide to provide drinking water, flood control, hydropower, irrigation, navigation, and water storage. Dams do indeed provide these things,but at the cost of several adverse, unexpected effects: disruption of ecosystems, decline of fish stocks, forced human and animal resettlements, and diseases such as malaria, which are borne by vectors that thrive in quiet waters. PMID:9349830

  18. MASTER PLAN ChiefJosephDamHatcheryProgram This Chief Joseph Dam Hatchery Program Master Plan

    E-print Network

    #12;i MASTER PLAN ChiefJosephDamHatcheryProgram This Chief Joseph Dam Hatchery Program Master Plan Fisheries Enhancement Group ChiefJosephDam HatcheryProgram M A S T E R P L A N #12;ChiefJosephDam Joseph Dam. The Okanogan River is the uppermost tributary of the Columbia that is still available

  19. EFFECT OF ENCROACHMENT OF WANAPUM DAM RESERVOIR ON FISH PASSAGE OVER ROCK ISLAND DAM, COLUMBIA RIVER

    E-print Network

    EFFECT OF ENCROACHMENT OF WANAPUM DAM RESERVOIR ON FISH PASSAGE OVER ROCK ISLAND DAM, COLUMBIA the lower sections of the three fish ladders at Rock Island Dam, 61 km upstream from Wanapum Dam of the center and left-bank fish ladders of Rock Island Dam were rebuilt and a new sequence of spill patterns

  20. Deer Creek Dam, Dam, 1,204 feet/238 degrees from intersection of ...

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

    Deer Creek Dam, Dam, 1,204 feet/238 degrees from intersection of dam complex access road and U.S. Highway 189 to center of dam, 874 feet/352 degrees from Hydroelectric Powerplant (HAER UT-93-B) to center of dam, Charleston, Wasatch County, UT

  1. Study of damage to a high concrete dam subjected to underwater shock waves

    NASA Astrophysics Data System (ADS)

    Lu, Lu; Li, Xin; Zhou, Jing

    2014-06-01

    To study the effect of a strong underwater shock wave on a concrete dam, this research aims to improve hammer impact methods in model tests. Six 1:200 scale models were designed and tested under distributed impact loads. A device was deployed for a direct measurement of the impact force at the upstream face of the dams. The model dam bases were anchored to prevent displacement. The experimental results indicate that the top part of the concrete dam is a weak zone, and the impact failure initiates with a fracture on the top of the dam. The peak value of impact stress increases when the second crack appears in the concrete dam from the upstream face to the downstream face. And, the level of the second crack in the dam body is lower as the peak value of impact stress increases. In this study, dynamic analysis was conducted by calculating the results to verify the effectiveness of a device to directly measure the impact force. This method may be used to approximately forecast the damage of concrete dam and may also be useful in other engineering applications.

  2. Neotectonics of the Vajont dam site

    NASA Astrophysics Data System (ADS)

    Mantovani, Franco; Vita-Finzi, Claudio

    2003-08-01

    The disastrous Vajont landslide (NE Italy) of 9 October 1963 is generally thought to have occurred on an existing failure surface. Reassessment of the morphological and structural evidence suggests that movement was on a normal fault plane which had juxtaposed Cretaceous limestone and highly fractured rock debris, thus rendering the dam site unusually susceptible to massive sliding. The proposed fault is consistent in strike with the regional lineament pattern. Although movement was triggered by the combined effects of heavy rainfall and changes in reservoir level, there is circumstantial evidence that seismicity played a contributory part in mobilising the slide by increasing pore pressure at the base of the slide as well as by any associated shaking.

  3. Hoover Dam Intake Towers Panorama

    USGS Multimedia Gallery

    Hoover Dam impounds Lake Mead and provides drinking water and hydroelectric power to the surrounding area. It was constructed between 1931 and 1936. The Intake Towers are where water enters to generate electricity....

  4. Concrete gravity dam stability analysis

    SciTech Connect

    Morris, D.

    1992-09-01

    Under Federal Energy Regulatory Commission (FERC) guidelines, dam owners must evaluate the stability of their structures every five years. Because traditional approaches typically yield overly conservative stability estimates, EPRI sponsored the development of a computer code, CG-DAMS, to provide more-realistic assessments that reflect site-specific conditions. This finite-element code-which is available in mainframe, workstation, and personal computer versions-can be used to predict crack growth, shear, and stress under a variety of loads.

  5. A pre-dam-removal assessment of sediment transport for four dams on the Kalamazoo River between Plainwell and Allegan, Michigan

    USGS Publications Warehouse

    Syed, Atiq U.; Bennett, James P.; Rachol, Cynthia M.

    2005-01-01

    Four dams on the Kalamazoo River between the cities of Plainwell and Allegan, Mich., are in varying states of disrepair. The Michigan Department of Environmental Quality (MDEQ) and U.S. Environmental Protection Agency (USEPA) are considering removing these dams to restore the river channels to pre-dam conditions. This study was initiated to identify sediment characteristics, monitor sediment transport, and predict sediment resuspension and deposition under varying hydraulic conditions. The mathematical model SEDMOD was used to simulate streamflow and sediment transport using three modeling scenarios: (1) sediment transport simulations for 730 days (Jan. 2001 to Dec. 2002), with existing dam structures, (2) sediment transport simulations based on flows from the 1947 flood at the Kalamazoo River with existing dam structures, and (3) sediment transport simulations based on flows from the 1947 flood at the Kalamazoo River with dams removed. Sediment transport simulations based on the 1947 flood hydrograph provide an estimate of sediment transport rates under maximum flow conditions. These scenarios can be used as an assessment of the sediment load that may erode from the study reach at this flow magnitude during a dam failure. The model was calibrated using suspended sediment as a calibration parameter and root mean squared error (RMSE) as an objective function. Analyses of the calibrated model show a slight bias in the model results at flows higher than 75 m3/s; this means that the model-simulated suspended-sediment transport rates are higher than the observed rates; however, the overall calibrated model results show close agreement between simulated and measured values of suspended sediment. Simulation results show that the Kalamazoo River sediment transport mechanism is in a dynamic equilibrium state. Model results during the 730-day simulations indicate significant sediment erosion from the study reach at flow rates higher than 55 m3/s. Similarly, significant sediment deposition occurs during low to average flows (monthly mean flows between 25.49 m3/s and 50.97 m3/s) after a high-flow event. If the flow continues to stay in the low to average range the system shifts towards equilibrium, resulting in a balancing effect between sediment deposition and erosion rates. The 1947 flood-flow simulations show approximately 30,000 m3 more instream sediments erosion for the first 21 days of the dams removed scenario than for the existing-dams scenario, with the same initial conditions for both scenarios. Application of a locally weighted regression smoothing (LOWESS) function to simulation results of the dams removed scenario indicates a steep downtrend with high sediment transport rates during the first 21 days. In comparison, the LOWESS curve for the existing-dams scenario shows a smooth transition of sediment transport rates in response to the change in streamflow. The high erosion rates during the dams-removed scenario are due to the absence of the dams; in contrast, the presence of dams in the existing-dams scenario helps reduce sediment erosion to some extent. The overall results of 60-day simulations for the 1947 flood show no significant difference in total volume of eroded sediment between the two scenarios, because the dams in the study reach have low heads and no control gates. It is important to note that the existing-dams and dams-removed scenarios simulations are run for only 60 days; therefore, the simulations take into account the changes in sediment erosion and deposition rates only during that time period. Over an extended period, more erosion of instream sediments would be expected to occur if the dams are not properly removed than under the existing conditions. On the basis of model simulations, removal of dams would further lower the head in all the channels. This lowering of head could produce higher flow velocities in the study reach, which ultimately would result in accelerated erosion rates.

  6. Human tails and pseudotails.

    PubMed

    Dao, A H; Netsky, M G

    1984-05-01

    A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin. Bone, cartilage, notochord, and spinal cord are lacking. The true tail arises by retention of structures found normally in fetal development. It may be as long as 13 cm, can move and contract, and occurs twice as often in males as in females. A true tail is easily removed surgically, without residual effects. It is rarely familial. Pseudotails are varied lesions having in common a lumbosacral protrusion and a superficial resemblance to persistent vestigial tails. The most frequent cause of a pseudotail in a series of ten cases obtained from the literature was an anomalous prolongation of the coccygeal vertebrae. Additional lesions included two lipomas, and one each of teratoma, chondromegaly , glioma, and a thin, elongated parasitic fetus. PMID:6373560

  7. Respiratory Failure

    MedlinePLUS

    ... What Is Respiratory Failure? Respiratory (RES-pih-rah-tor-e) failure is a condition in which not ... the help of a ventilator (VEN-til-a-tor). A ventilator is a machine that supports breathing. ...

  8. Assessing low-activity faults for the seismic safety of dams

    SciTech Connect

    Page, W.D.; Savage, W.U.; McLaren, M.K.

    1995-12-31

    Dams have been a familiar construct in the northern Sierra Nevada range in California (north of the San Joaquin River) since the forty-niners and farmers diverted water to their gold mines and farms in the mid 19th century. Today, more than 370 dams dot the region from the Central Valley to the eastern escarpment. Fifty-five more dam streams on the eastern slope. The dams are of all types: 240 earth fill; 56 concrete gravity; 45 rock and earth fills; 35 rock fill; 14 concrete arch; 9 hydraulic fill; and 29 various other types. We use the northern Sierra Nevada to illustrate the assessment of low-activity faults for the seismic safety of dams. The approach, techniques, and methods of evaluation are applicable to other regions characterized by low seismicity and low-activity faults having long recurrence intervals. Even though several moderate earthquakes had shaken the Sierra Nevada since 1849 (for example, the 1875 magnitude 5.8 Honey Lake and the 1909 magnitudes 5 and 5.5 Downieville earthquakes), seismic analyses for dams in the area generally were not performed prior to the middle of this century. Following the 1971 magnitude 6.7 San Fernando earthquake, when the hydraulic-fill Lower Van Norman Dam in southern California narrowly escaped catastrophic failure, the California Division of Safety of Dams and the Federal Energy Regulatory Commission required seismic safety to be addressed with increasing rigor. In 1975, the magnitude 5.7 Oroville earthquake on the Cleveland Hill fault near Oroville Dam in the Sierra Nevada foothills, showed convincingly that earthquakes and surface faulting could occur within the range. Following this event, faults along the ancient Foothills fault system have been extensively investigated at dam sites.

  9. Wagging tail vibration absorber

    NASA Technical Reports Server (NTRS)

    Barclay, R. G.; Humphrey, P. W.

    1969-01-01

    A 750-foot cantilever length of extendible-tape boom (very low stiffness) was considered as the main system to be damped. A number of tail lengths were tried from 20 feet to 80 feet after which 40 feet was investigated further as a desirable compromise between performance and practical lengths. A 40-foot damping tail produced a damping effect on the main boom for the first mode equivalent in decay rate to 3.1 percent of critical damping. In this case the spring-hinge and tail were tuned to the main boom first mode frequency and the hinge damping was set at 30 percent of critical based on the tail properties. With this same setting, damping of the second mode was .4 percent and the third mode .1 percent.

  10. Beaver dams, hydrological thresholds, and controlled floods as a management tool in a desert riverine ecosystem, Bill Williams River, Arizona

    USGS Publications Warehouse

    Andersen, D.C.; Shafroth, P.B.

    2010-01-01

    Beaver convert lotic stream habitat to lentic through dam construction, and the process is reversed when a flood or other event causes dam failure. We investigated both processes on a regulated Sonoran Desert stream, using the criterion that average current velocity is < 0.2 m s-1 in a lentic reach. We estimated temporal change in the lotic:lentic stream length ratio by relating beaver pond length (determined by the upstream lentic-lotic boundary position) to dam size, and coupling that to the dam-size frequency distribution and repeated censuses of dams along the 58-km river. The ratio fell from 19:1 when no beaver dams were present to < 3:1 after 7 years of flows favourable for beaver. We investigated the dam failure-flood intensity relationship in three independent trials (experimental floods) featuring peak discharge ranging from 37 to 65 m3 s-1. Major damage (breach ??? 3-m wide) occurred at ??? 20% of monitored dams (n = 7-86) and a similar or higher proportion was moderately damaged. We detected neither a relationship between dam size and damage level nor a flood discharge threshold for initiating major damage. Dam constituent materials appeared to control the probability of major damage at low (attenuated) flood magnitude. We conclude that environmental flows prescribed to sustain desert riparian forest will also reduce beaver-created lentic habitat in a non-linear manner determined by both beaver dam and flood attributes. Consideration of both desirable and undesirable consequences of ecological engineering by beaver is important when optimizing environmental flows to meet ecological and socioeconomic goals. ?? 2010 John Wiley & Sons, Ltd.

  11. Between residual tail dependence and

    E-print Network

    Gilleland, Eric

    Between residual tail dependence and Hüsler­Reiss triangular arrays 1. Tail Dependence Parameters 2. Maxima of Normal Random Vectors 3. Testing Tail Dependence Based on Radial Component 4. An Application Between residual tail­dependence and Hüsler­Reiss triangular arrays R.­D. Reiss joint work with M. Frick

  12. Three Gorges Dam, China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This ASTER image shows a 60 km stretch of the Yangtze River in China, including the Xiling Gorge, the eastern of the three gorges. In the left part of the image is the construction site of the Three Gorges Dam, the world's largest.

    This image was acquired on July 20, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    Size: 60 x 24 km (36 x 15 miles) Location: 30.6 deg. North lat., 111.2 deg. East long. Orientation: North at top Image Data: ASTER bands 1,2, and 3. Original Data Resolution: 15 m Date Acquired: July 20, 2000

  13. 17. VIEW OF MAIN AND DIVERSION DAMS FROM WATERGATE AFTER ...

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

    17. VIEW OF MAIN AND DIVERSION DAMS FROM WATER-GATE AFTER REMOVAL OF DRIFTWOOD. DIVERSION DAM IN LEFT FOREGROUND, MAIN DAM TO THE RIGHT. Photographed July 18, 1938. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

  14. OVERALL VIEW OF CASCADE CANAL COMPANY CRIB DAM, LOOKING UPSTREAM ...

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

    OVERALL VIEW OF CASCADE CANAL COMPANY CRIB DAM, LOOKING UPSTREAM FROM DIRECTION OF KACHESS DAM. VIEW TO NORTH - Kachess Dam, 1904 Cascade Canal Company Crib Dam, Kachess River, 1.5 miles north of Interstate 90, Easton, Kittitas County, WA

  15. Teton Dam flood of June 1976, Pingree quadrangle, Idaho

    USGS Publications Warehouse

    Hubbard, Larry L.; Bartells, John H.

    1976-01-01

    The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Pingree quadrangle. (Woodard-USGS)

  16. Teton Dam flood of June 1976, Parker quadrangle, Idaho

    USGS Publications Warehouse

    Thomas, Cecil Albert; Ray, Herman A.

    1976-01-01

    The failure of Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls, Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Parker quadrangle. (Woodard-USGS)

  17. Using computers for analyzing dam stability during floods

    SciTech Connect

    Lau, S.C.; Cecilio, C.

    1993-12-31

    Determining the required spillway capacity during a flood for a single dam is relatively straightforward using present-day computer-based tools. However, the analysis becomes more challenging when several dams form a series on the same river. Computer models are available to assist in this task. This paper is a discussion of one of these models...the DAMBRK computer code. This program consists of three parts: (1) A description of the failure, (2) Computation of the time-history of the outflow through the breach, and (3) Routing of the outflow through the downstream valley to determine the resulting water stages and wave travel times of the flood. A case study is presented.

  18. Multiple flow processes accompanying a dam-break flood in a small upland watershed, Centralia, Washington

    USGS Publications Warehouse

    Costa, John E.

    1994-01-01

    On October 5, 1991, following 35 consecutive days of dry weather, a 105-meter long, 37-meter wide, 5.2-meter deep concrete-lined watersupply reservoir on a hillside in the eastern edge of Centralia, Washington, suddenly failed, sending 13,250 cubic meters of water rushing down a small, steep tributary channel into the city. Two houses were destroyed, several others damaged, mud and debris were deposited in streets, on lawns, and in basements over four city blocks, and 400 people were evacuated. The cause of failure is believed to have been a sliding failure along a weak seam or joint in the siltstone bedrock beneath the reservoir, possibly triggered by increased seepage into the rock foundation through continued deterioration of concrete panel seams, and a slight rise (0.6 meters) in the pool elevation. A second adjacent reservoir containing 18,900 cubic meters of water also drained, but far more slowly, when a 41-cm diameter connecting pipe was broken by the landslide. The maximum discharge resulting from the dam-failure was about 71 cubic meters per second. A reconstructed hydrograph based on the known reservoir volume and calculated peak discharge indicates the flood duration was about 6.2 minutes. Sedimentologic evidence, high-water mark distribution, and landforms preserved in the valley floor indicate that the dam failure flood consisted of two flow phases: an initial debris flow that deposited coarse bouldery sediment along the slope-area reach as it lost volume, followed soon after by a water-flood that achieved a stage about one-half meter higher than the debris flow. The Centralia dam failure is one of three constructed dams destroyed by rapid foundation failure that defines the upper limits of an envelope curve of peak flood discharge as a function of potential energy for failed constructed dams worldwide.

  19. The Dramatic Methods of Hans van Dam.

    ERIC Educational Resources Information Center

    van de Water, Manon

    1994-01-01

    Interprets for the American reader the untranslated dramatic methods of Hans van Dam, a leading drama theorist in the Netherlands. Discusses the functions of drama as a method, closed dramatic methods, open dramatic methods, and applying van Dam's methods. (SR)

  20. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...31, 1995. A summary of the hazard potential criteria...locations.html. (3) For high hazard potential dams, the borrower...Emergency action plan. For high hazard potential dams, the borrower...Federal Guidelines for Earthquake Analysis and Design of...

  1. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...31, 1995. A summary of the hazard potential criteria...locations.html. (3) For high hazard potential dams, the borrower...Emergency action plan. For high hazard potential dams, the borrower...Federal Guidelines for Earthquake Analysis and Design of...

  2. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...31, 1995. A summary of the hazard potential criteria...locations.html. (3) For high hazard potential dams, the borrower...Emergency action plan. For high hazard potential dams, the borrower...Federal Guidelines for Earthquake Analysis and Design of...

  3. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...31, 1995. A summary of the hazard potential criteria...locations.html. (3) For high hazard potential dams, the borrower...Emergency action plan. For high hazard potential dams, the borrower...Federal Guidelines for Earthquake Analysis and Design of...

  4. Simulation of Breach Outflow for Earthfill Dam

    NASA Astrophysics Data System (ADS)

    Razad, Azwin Zailti Abdul; Sabri Muda, Rahsidi; Mohd Sidek, Lariyah; Azia, Intan Shafilah Abdul; Hanum Mansor, Faezah; Yalit, Ruzaimei

    2013-06-01

    Dams have been built for many reasons such as irrigation, hydropower, flood mitigation, and water supply to support development for the benefit of human. However, the huge amount of water stored behind the dam can seriously pose adverse impacts to the downstream community should it be released due to unwanted dam break event. To minimise the potential loss of lives and property damages, a workable Emergency Response Plan is required to be developed. As part of a responsible dam owner and operator, TNB initiated a study on dam breach modelling for Cameron Highlands Hydroelectric Scheme to simulate the potential dam breach for Jor Dam. Prediction of dam breach parameters using the empirical equations of Froehlich and Macdonal-Langridge-Monopolis formed the basis of the modelling, coupled with MIKE 11 software to obtain the breach outflow due to Probable Maximum Flood (PMF). This paper will therefore discuss the model setup, simulation procedure and comparison of the prediction with existing equations.

  5. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...available from FEMA: (i)“Emergency Action Planning Guidelines for Dams,”FEMA 64. (ii)“Federal Guidelines for Earthquake Analysis and Design of Dams,”FEMA 65. (iii)“Federal Guidelines for Selecting and Accommodating Inflow Design...

  6. Experiences with embankment dam overtopping protection

    SciTech Connect

    Powledge, G.R. ); Pravdivets, Y.P. )

    1994-02-01

    Several methods are available for use in protecting embankment dams that may be over-topped. This article focuses on the successful use of two of those methods - cellular concrete mats and wedge-shaped blocks - on existing dams.

  7. Dams Securing Water for Our Future 1 ICOLD Bulletin on Dam Safety Management

    E-print Network

    Bowles, David S.

    Dams ­ Securing Water for Our Future 1 ICOLD Bulletin on Dam Safety Management David S. Bowles 1 , Michel Poupart 6 , David Stewart 5 , Przemyslaw A. Zielinski 7 1 Institute for Dam Safety Risk The ICOLD Committee on Dam Safety (CODS) "was established as a coordinating body to assure

  8. Uranium mill tailings stabilization

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-02-01

    Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration.

  9. Annual Fish Passage Report -Rock Island Dam

    E-print Network

    Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965 By Paul D. Zimmer L. McKeman, Director Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965;#12;Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965 By PAUL D. ZIMMER, Fishery

  10. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-print Network

    ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON 1960 . SPECIAL SCIENTIFIC ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1960 by Paul D. Zimmer and Clifton C. Davidson United States Fish This annual report of fishway operations at Rock Island Dam in 1960 is dedicated to the memory of co

  11. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-print Network

    ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1959 :y .iiJA/i-3ri ^' WUUUi. ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1959 by Paul D. Zimmer, Clifton and observations 10 Summary 13 #12;#12;ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON

  12. On Quantum Computation Theory Wim van Dam

    E-print Network

    Koolen, Marijn

    On Quantum Computation Theory Wim van Dam #12;#12;On Quantum Computation Theory #12;ILLC woensdag 9 oktober 2002, te 14.00 uur door Willem Klaas van Dam geboren te Breda. #12;Promotor: Prof. dr. P Dam, 2002 ISBN: 90­5776­091­6 #12;" . . . Many errors have been made in the world which today

  13. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-print Network

    42) ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON 1961 Marine Biological. McKeman, Director ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1961--Fisheries No. 421 Washington, D. C. April 1962 #12;Rock Island Dam, Columbia River, Washington ii #12;CONTENTS

  14. Webinar: Stepped chute design for embankment dams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changing demographics in the vicinity of dams have led to hazard creep in a number of dams worldwide. Many of these dams now have insufficient spillway capacity as a result of these changes in hazard classification from low to significant or high hazard. Stepped chutes applied to the embankment da...

  15. Inception point for embankment dam stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped spillways applied to embankment dams have become a common design practice with the rehabilitation of aging watershed dams, especially those experiencing a hazard classification change from low to high hazard. Previous research on stepped spillways focused on gravity dams where aerated flow ...

  16. ALLOWABLE OVERTOPPING OF EARTHEN DAMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aging of the nation’s flood control infrastructure has resulted in a need for reevaluation, and, in some instances rehabilitation, of existing earthen dams. Inadequate spillway capacity is often one of the deficiencies identified for these structures. Inadequate spillway capacity may be the result...

  17. INTERNATIONAL COMMISSION ON LARGE DAMS

    E-print Network

    Bowles, David S.

    the pressures of public policy making, the scientific community has ample time to fight its internal battles is not a scientific endeavour per se. Therefore it is important to distinguish between the pursuit of scientific inquiry leading to "scientific credibility", and the "credibility" of dam safety decisions based on risk

  18. Subdaily Hydrologic Variability by Dams

    NASA Astrophysics Data System (ADS)

    Costigan, K. H.; Ruffing, C.; Smith, J. M.; Daniels, M. D.

    2012-12-01

    The effects dams have on hydrologic, geomorphic, and ecologic regimes has been well characterized using mean daily discharge. Subdaily discharge variation (herein flashiness) has not been well characterized for a variety of dam, watershed, and land cover characteristics. The hourly hydrologic records for 30 sites across the continental United States were analyzed for flashiness using the Richards-Baker Index, coefficient of daily variation, percent of total flow variation, and the percent of the year when daily discharge is greater than mean daily discharge. The goal of this analysis is to evaluate the role of catchment variables such as mean slope and land use conditions across receiving watersheds in predicting flashiness; compare flashiness metrics across sites to identify relationships between dam related variables such as type and size; and determine the most appropriate temporal extent for assessing flashiness in streamflow. Our approach relies on data at the watershed scale with a fine temporal grain to determine flashiness over a decade of operation for each dam.

  19. Middle Dam (Maine) Well Drilling

    USGS Multimedia Gallery

    USGS hydrologist Martha Nielsen examines cuttings as a drill crew works to drill a new monitoring well at USGS station 443647070552303 (ME-OW400A) near Middle Dam on Lower Richardson Lake. The existing well heaved due to frost and had to be replaced....

  20. Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model

    NASA Astrophysics Data System (ADS)

    Ren, Liang; Chen, Jianyun; Li, Hong-Nan; Song, Gangbing; Ji, Xueheng

    2009-03-01

    Accurate measurement of strain variation and effective prediction of failure within models have been major objectives for strain sensors in dam model tests. In this paper, a fiber Bragg grating (FBG) strain sensor with enhanced strain sensitivity that is packaged by two gripper tubes is presented and applied in the seismic tests of a small-scale dam model. This paper discusses the principle of enhanced sensitivity of the FBG strain sensor. Calibration experiments and reliability tests were conducted to evaluate the sensor's strain transferring characteristics on plates of different material. This paper also investigates the applicability of the FBG strain sensors in seismic tests of a dam model by conducting a comparison between the test measurements of FBG sensors and analytical predictions, monitoring the failure progress and predicting the cracking inside the dam model. Results of the dam model tests prove that the FBG strain sensor has the advantages of small size, high precision, and embeddability. It has a promising potential in the cracking and failure monitoring and identification of the dam model.

  1. Constraining the timing of the most recent cataclysmic flood event from ice-dammed lakes in the Russian Altai Mountains, Siberia, using cosmogenic in situ 10Be

    NASA Astrophysics Data System (ADS)

    Reuther, Anne U.; Herget, Jürgen; Ivy-Ochs, Susan; Borodavko, Pavel; Kubik, Peter W.; Heine, Klaus

    2006-11-01

    Ice-dammed lakes were repeatedly formed in intermontane basins in the Russian Altai Mountains throughout the Pleistocene. These cataclysmic outburst floods, caused by ice-dam failures, were documented as Earth's largest flood waves by other geoscientists. Using in situ 10Be, we successfully dated surfaces of flood-associated boulders located in a former lake basin and downvalley from a former ice dam. Our precise surface exposure ages suggest that all boulders were associated with the most recent out of a number of cataclysmic floods that occurred at 15.8 ± 1.8 ka. The field location of the boulders implies that they were deposited by the largest late Pleistocene flood that drained the Chuya-Katun Lake completely following initial dam failure. A published reconstruction of the late glacial paleoenvironment in the vicinity of the former ice dam indicates that dam failure was likely a result of climatically induced downwasting of glaciers. The failure of the ice dam provides more evidence for the timing of widespread warming during the late glacial in southern Russia. This flooding event in the headwaters of the Ob River coincides with a freshwater peak as recorded in isotopic records of the Kara Sea and the Arctic Ocean.

  2. Geomorphic evolution to large check-dam removal on a mountain river in Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, H.; Kuo, W.

    2012-12-01

    As aging dams become obsolete or economically inefficient, dam removal has become an important aspect of river restoration in recent years. While various efforts are ongoing to enhance our understanding, studies documenting the physical and ecological responses to dam removal are still lacking, particularly for removal of large dams in mountain river and following major flood, where the size of watersheds and the amount of reservoir sediment released can be much greater than for most previously studied dam removals. This presentation documents the geomorphic evolution to removal of a large dam on a coarse-grained, steep (an order of magnitude greater than on the Marmot) mountain channel in Taiwan. The Chijiawan creek is the only habitat in Taiwan of the endangered Formosan landlocked salmon. Its habitat has been cut significantly since the 1960s following construction of check dams designed to prevent reservoir sedimentation downstream. The largest and lowermost barrier on Chijiawan creek is the 15m high, "No. 1 Check Dam" built in 1971. Forty years later, the dam had backfilled with about an estimated 0.2 million m3 sediment and its toe had been scoured about 4m below its foundation, raising a significant risk of dam failure. For these reasons, the Shei-Pa National Park removed the dam in late May 2011. To monitor the channel response to dam removal, we conducted surveys of grain size distributions, cross-sectional and longitudinal profiles, analyzed the stage and turbidity records, and carried out repeat photography. Channel changes were greatest immediately following removal as a result of the high stream power, steep energy slope, and unconsolidated alluvial fill behind the dam. Headcut propagation caused immediate removal of the sand-grade sediment and progressive channel widening. One month after dam removal, a minor flood event with the estimated peak discharge of 20 m3/s excavated a big wedge of sediment from the impoundment. Two months after dam removal, erosion had propagated 300m upstream into the impounded sediment along a bed profile of gradient at 1.4% at a headcut with a local gradient of 5.1%. The profile remained pretty much unchanged until a year after in June 2012 during a 'plum rain' with the estimated discharge of 110 m3/s. Headcut erosion migrated further up to 500m upstream from the dam and lateral erosion was documented reaching up to 50m in cross sections near the dam. An estimated amount of about 50,000 m3 sediment was released and deposited in the 1.5-km reach downstream. The change in grain size was a fining of the sediment at the two downstream sites and a slight coarsening at the upstream site from April 2010 to July 2011, and significant coarsening of the sediment (with D50 from 10 mm to 75 mm) at the downstream site and upstream site as well from July 2011 to July 2012. This is likely due to the increase in energy upstream of the dam post-removal, which has transported the fine-grained sediments downstream for the first few months. Following the major flood in June 2012, the coarser-grained sediments have been released downstream. As the river is still adjusting, we anticipate the observations will enhance understanding for all those concerned with dam removal and river restoration.

  3. Remotely installed steam generator nozzle dam system

    SciTech Connect

    Mc Donald, F.X.; Weisel, E.M.; Schukei, G.E.

    1990-09-04

    This patent describes a method for remotely installing a dam unit in a nozzle or a nuclear steam generator head, the head including a manway. It comprises: mounting an articulated manipulator to an internal surface of the head, the manipulator having a free end which carries a jaw member; positioning the manipulator so that the jaw member is adjacent the manway and substantially on the manway axis; passing a first dam segment through the manway and attaching the jaw member to the first segment; positioning the manipulator so that the jaw member holds the first dam segment on one side of the manway axis; passing a second dam segment through the manway into engagement with the first dam segment to form a dam subassembly; translating the manipulator through the head until the dam subassembly is adjacent the nozzle; advancing the jaw member toward the nozzle until the cam subassembly is positioned substantially at the desired location of the dam unit with respect to the nozzle; and deploying the manipulator to install dam support structure between the dam subassembly and the steam generator, thereby forming an installed dam unit.

  4. Seismic safety of high concrete dams

    NASA Astrophysics Data System (ADS)

    Chen, Houqun

    2014-08-01

    China is a country of high seismicity with many hydropower resources. Recently, a series of high arch dams have either been completed or are being constructed in seismic regions, of which most are concrete dams. The evaluation of seismic safety often becomes a critical problem in dam design. In this paper, a brief introduction to major progress in the research on seismic aspects of large concrete dams, conducted mainly at the Institute of Water Resources and Hydropower Research (IWHR) during the past 60 years, is presented. The dam site-specific ground motion input, improved response analysis, dynamic model test verification, field experiment investigations, dynamic behavior of dam concrete, and seismic monitoring and observation are described. Methods to prevent collapse of high concrete dams under maximum credible earthquakes are discussed.

  5. REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK ...

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

    REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK STAND, SHOWING AIRCRAFT NUMBER (319), HORIZONTAL STABILIZER, TAIL CONE AND COOLING CTS FOR THE AUXILIARY POWER UNIT (APU), MECHANIC PAUL RIDEOUT IS LOWERING THE BALANCE PANELS ON THE STABILIZERS FOR LUBRICATION AND INSPECTION. - Greater Buffalo International Airport, Maintenance Hangar, Buffalo, Erie County, NY

  6. On tails of perpetuities

    E-print Network

    Hitczenko, Pawel

    2011-01-01

    We establish an upper bound on the tails of a random variable that arises as a solution of a stochastic difference equation. In the non--negative case our bound is similar to a lower bound obtained by Goldie and Gr\\"ubel in 1996.

  7. Dynamic decision making for dam-break emergency management - Part 1: Theoretical framework

    NASA Astrophysics Data System (ADS)

    Peng, M.; Zhang, L. M.

    2013-02-01

    An evacuation decision for dam breaks is a very serious issue. A late decision may lead to loss of lives and properties, but a very early evacuation will incur unnecessary expenses. This paper presents a risk-based framework of dynamic decision making for dam-break emergency management (DYDEM). The dam-break emergency management in both time scale and space scale is introduced first to define the dynamic decision problem. The probability of dam failure is taken as a stochastic process and estimated using a time-series analysis method. The flood consequences are taken as functions of warning time and evaluated with a human risk analysis model (HURAM) based on Bayesian networks. A decision criterion is suggested to decide whether to evacuate the population at risk (PAR) or to delay the decision. The optimum time for evacuating the PAR is obtained by minimizing the expected total loss, which integrates the time-related probabilities and flood consequences. When a delayed decision is chosen, the decision making can be updated with available new information. A specific dam-break case study is presented in a companion paper to illustrate the application of this framework to complex dam-breaching problems.

  8. Ranking procedure on maintenance tasks for monitoring of embankment dams

    SciTech Connect

    Andersen, G.R.; Chouinard, L.E.; Bouvier, C.; Back, W.E.

    1999-04-01

    A multistep strategy for the prioritization of maintenance and repair funds for the monitoring of embankment dams is proposed wherein the most important device in the worst condition is preferred. The strategy involves determining the importance of each device (in terms of dam safety) and measuring its condition through field inspections. A condition definition for each device is developed in terms of its ability to function optimally in its diagnostic role. Relative importance of the monitoring devices is defined in terms of diagnostic value and proceeds by considering: (1) the failure modes and their conditional probabilities; (2) adverse conditions and their conditional probabilities; (3) indicators that provide information on these adverse conditions and their relative diagnostic value; and (4) monitoring devices that are used to assess the presence of the indicators and their relative diagnostic value. A panel of dam safety experts is used to answer the questions necessary to implement this methodology through a process of expert elicitation. An interactive DOS-based C++ computer program has been developed to assist in the expert elicitation necessary to implement this methodology.

  9. Maple River Dam Spillway Comparison

    USGS Multimedia Gallery

    Maple River Dam spillway comparison in 2011. The top photo was taken on July 14, 2011, with a gage height of 1,027.30 feet and a streamflow of 809 cubic feet per second. The bottom photo was taken on April 13, 2011, with a gage height of 1,052.95 feet and a streamflow of 4,960 cubic feet per second....

  10. Egypt: after the Aswan Dam

    SciTech Connect

    Walton, S.

    1981-05-01

    Ten years after its completion, the controversial Aswan High Dam's hydrologic and human consequences are clearer because of a joint US-Egyptian interdisciplinary study. Water supply and distribution is emerging as a major world resource problem with the recognition that unsafe drinking water and inadequate sanitation contribute to health problems. Dams provide water supplies, but they also create conditions favorable to the spread of water-borne diseases. The Aswan Dam solved problems of flooding and drought by opening 2.5 million acres to year-round irrigation, although some of the reclaimed land has been lost to urban expansion and shoreline erosion, and provides hydroelectric power. The negative effects include increasing soil salinity, changes in the water table, excessive downstream water plant growth, and diseases such as schistosomiasis and other intestinal parasites, and the social impact on the Nubians, whose homeland was flooded. Planners must use the information gathered in this study to see that the benefits outweigh the human costs. 22 references, 7 figures.

  11. Heart Failure

    MedlinePLUS

    ... this? Submit What's this? Submit Button Related CDC Web Sites Heart Disease Stroke High Blood Pressure Salt ... to Prevent and Control Chronic Diseases Million Hearts® Web Sites with More Information About Heart Failure For ...

  12. Kidney Failure

    MedlinePLUS

    ... Dialysis or Transplant Paying for Kidney Failure Treatment Contact Us Health Information Center Phone: 1-800-860- ... to share this content freely. October 2, 2013 Contact Us Health Information Center Phone: 1-800-860- ...

  13. Remotely installed steam generator nozzle dam system

    SciTech Connect

    Evans, C.; Shah, J. ); Kaye, R. )

    1990-01-01

    The Busitech Remotely Installed Nozzle Dam System is for use in Westinghouse Design Nuclear Steam Generators (S/G). These Nozzle Dams are used to isolate the primary channel head of the S/G from the primary coolant loop during the refueling process. This paper addresses the attributes of these Nozzle Dams utilized in the Westinghouse Steam Generator and does not address the Nozzle Dams utilized in the Combustion Engineering or Babcock and Wilcox Steam Generators. This Nozzle Dam System has a remote installation option which will allow installation of the Nozzle Dam with zero entry into the S/G primary channel head. The advantages of this total system is a significant reduction in radiation exposure, manpower and time of installation.

  14. Exporting dams: China's hydropower industry goes global.

    PubMed

    McDonald, Kristen; Bosshard, Peter; Brewer, Nicole

    2009-07-01

    In line with China's "going out" strategy, China's dam industry has in recent years significantly expanded its involvement in overseas markets. The Chinese Export-Import Bank and other Chinese financial institutions, state-owned enterprises, and private firms are now involved in at least 93 major dam projects overseas. The Chinese government sees the new global role played by China's dam industry as a "win-win" situation for China and host countries involved. But evidence from project sites such as the Merowe Dam in Sudan demonstrates that these dams have unrecognized social and environmental costs for host communities. Chinese dam builders have yet to adopt internationally accepted social and environmental standards for large infrastructure development that can assure these costs are adequately taken into account. But the Chinese government is becoming increasingly aware of the challenge and the necessity of promoting environmentally and socially sound investments overseas. PMID:18992986

  15. DRAFT ENVIRONMENTAL ASSESSMENT1 PINE CREEK DAM, OKLAHOMA2

    E-print Network

    US Army Corps of Engineers

    #12;#12;DRAFT ENVIRONMENTAL ASSESSMENT1 PINE CREEK DAM, OKLAHOMA2 DAM SAFETY MODIFICATION3 &4 Environmental Assessment Pine Creek Dam, Oklahoma Dam Safety Modification & Interim Risk Reduction Measure and risk reduction measures necessary to correct structural and maintenance deficiencies of Pine Creek Dam

  16. View of upstream face of the forebay dam of Grand ...

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

    View of upstream face of the forebay dam of Grand Coulee Dam, looking west. Construction of the forebay dam, which replaced the eastern end of the original Grand Coulee Dam, was completed in 1974. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  17. 18. DETAIL AT JUNCTION OF MAIN DAM AT LEFT AND ...

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

    18. DETAIL AT JUNCTION OF MAIN DAM AT LEFT AND DIVERSION DAM AT RIGHT SHOWING LOG CRIBBING. SPACES INSIDE CRIBBING WERE FILLED WITH STONE TO ANCHOR DAM; DETERIORATION OF DAM HAS ALLOWED STONE BALLAST TO WASH AWAY. Photographed July 18, 1938. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

  18. 78 FR 53494 - Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ...Modifications of Dam Structures: Combination of Concrete Floodwalls and Earthen Embankments...Bar). TVA also installed a permanent concrete apron on approximately 2 acres of the...Modifications of Dam Structures: Combination of Concrete Floodwalls and Earthen...

  19. Lochnagar landslide-dam, Central Otago, New Zealand: geomechanics and timing of the formative event(s)

    NASA Astrophysics Data System (ADS)

    Augustinus, P. M.; Sweeney, C.; Brideau, M.; Fink, D.

    2013-12-01

    The sudden breach of natural rockslide dams is a major safety issue in mountain areas, although unbreached rockslide-dammed lakes such as Lochnagar in Central Otago, New Zealand, may persist in the landscape for millennia. The Lochnagar landslide-dam is located within the steep schistose mountains of the Southern Alps of New Zealand. During an extensive study of the site, structural and Schmidt hammer measurements were taken from the immediate area of the failure, as well as samples collected for laboratory analysis. Point load estimates of the uniaxial compressive strength were 85 MPa perpendicular and 18 MPa parallel to the schistosity. The rock mass quality was estimated using the Geological Strength Index with values of 35-45 observed. These results were used in a series of numerical modelling techniques: kinematic analysis, limit equilibrium and distinct element modelling. The results of the numerical modelling suggest that a wedge failure with toe buckling or ploughing through its rockmass is the likely failure mechanism. An observed fault zone at the base of the landslide may have preconditioned the slope to failure by weakening the toe. Preliminary ages from a program of 10Be exposure age dating, indicate that the landslide that formed the dam is of at least early Holocene age so that debuttressing after late glacial retreat could also be a contributing factor to landslide formation. Furthermore, the landslide deposit developed during multiple slope failure events that may have a seismotectonic origin.

  20. Analysis and dynamic modeling of a moraine failure and glacier lake outburst flood at Ventisquero Negro, Patagonian Andes (Argentina)

    NASA Astrophysics Data System (ADS)

    Worni, Raphael; Stoffel, Markus; Huggel, Christian; Volz, Christian; Casteller, Alejandro; Luckman, Brian

    2012-06-01

    SummaryAlthough moraine dams are inherently prone to failure because of their often weak structure, loose internal composition and lack of an engineered spillway, the understanding of dam breaching processes remains largely incomplete and appropriate modeling approaches are scarce. This paper analyzes a recent glacier lake outburst, caused by the failure of the terminal moraine of Ventisquero Negro (Patagonian Andes, Argentina) in May 2009. The dam breach trigger, breaching and lake emptying processes, plus the dynamics of the outburst flood were reconstructed based on field evidence and the application of a dynamic dam break model. Results indicate that the moraine failure was caused most probably by a rising lake level due to heavy precipitation, resulting in high lake outflow which led to dam erosion and finally to dam failure. The lake volume of ca. 10 × 106 m3 was released in ca. 3 h, producing high-discharge (ca. 4100 m3 s-1) debris flows and hyperconcentrated flows as the escaping water entrained large volumes of clastic material. The methodology presented in this paper provides valuable insights into complex dam breach and GLOF processes, and closes a critical gap in dynamic dam break modeling aimed at providing the lake outburst hydrograph. An accurate determination of outburst hydrographs constitutes one of the most crucial aspects for hazard assessment of unstable lakes and will gain further importance with ongoing glacier retreat and glacier lake formation.

  1. Geomorphic Responses to Check-Dam Removal on a Steep Mountain River in Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, H. W.; Kuo, W. C.

    2014-12-01

    The Chijiawan creek, located in the mountains of Central Taiwan with a strongly seasonal hydrology, high discharge and sediment yields, is the only habitat in Taiwan of the endangered Formosan landlocked salmon. The 13-m-high No. 1 Check Dam was the largest and lowermost barrier on Chijiawan creek built in 1972. After forty years, the dam had 4-m scouring holes below its foundation, raising a significant risk of dam failure. Due to the safety concern and habitat restoration, the Shei-Pa National Park removed the dam in late May 2011. This paper documents the channel evolution after its removal by focusing on understanding the geomorphic responses to sediment processes and complexities of hydrological processes. We collected the hourly discharge data of a Taipower gaging station located 6.8 km from the dam from 2010 to 2013 and conducted surveys of grain size distributions, cross-sectional and longitudinal profiles, and carried out repeat photography. One month after dam removal, a one-year event (Typhoon Meari) excavated a wedge of sediment from the impoundment. The knickpoint migrated to 200 m upstream from the dam and about 20,000 m3 of sediment had eroded from the reservoir. The profile remained pretty much unchanged until a year after in June 2012. Following a 20-year event (Typhoon Saola) in August 2012, the highest flow after dam removal to present, the channel significantly changed and the knickpoint migrated to 800 m upstream to the dam. The cumulative eroded amount increased to 150,000 m3, about three-thirds of the former impounded sediment. After a 5-year event (Typhoon Soulik) later on in July 2013, the knickpoint did not show much difference and the eroded amount of impounded sediment only increased 10,000 m3. However, the surveyed cross-sections showed obvious channel form changes and thalweg migration. It is likely that the entire bed was mobilized during the earlier high flows (Typhoon Saola), resulting in more easily mobilized bed material. As many dams in Taiwan are located in steep mountainous area with highly variable hydrologic condition, we anticipate the observations will help enhancing future similar dam removal projects.

  2. 78 FR 60271 - Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ... Federal Energy Regulatory Commission Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of..., Hollow Dam Power Company (transferor) and Ampersand Hollow Dam Hydro, LLC (transferee) filed an application for transfer of license for the Hollow Dam Project, FERC No. 6972, located on the West Branch...

  3. 33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). 100.1102 Section... Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). (a) General. Sponsors are... Roadrunner Resort and Headgate Dam). Bullhead City Boat Drags Sponsor: Sunshine Promotions Date: 2 to...

  4. Green River Locks and Dams 3, 4, 5, 6 and Barren River Lock and Dam 1 Disposition, Kentucky

    E-print Network

    US Army Corps of Engineers

    Green River Locks and Dams 3, 4, 5, 6 and Barren River Lock and Dam 1 Disposition, Kentucky 16 September 2014 ABSTRACT: Green River Locks and Dams 3 through 6 and Barren River Lock and Dam 1 were. The Green River Locks and Dams 5 and 6 ceased operations in 1951 due to a marked decline in navigation

  5. 33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Texas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado... § 208.19 Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado...shall operate the Marshall Ford Dam and Reservoir in accordance with the water...

  6. Time-Lapse Seismic Tomography and Electrical Resistivity Mapping of a Small Embankment Dam with Possible Zones of Weakness

    NASA Astrophysics Data System (ADS)

    Wodajo, L. T.; Hickey, C. J.; Song, C. R.

    2013-12-01

    Earthen dam or levee failure can occur with little to no warning. Internal problems such as seepage and piping are among the major causes of failure in earthen embankment dams and levees. Identifying and mitigating these problems requires a cost effective and non-invasive method of investigating these critical structures. This study focuses on the early detection of internal problems such as seepage and piping using time lapse seismic refraction tomography (SRT) and electrical resistivity tomography (ERT). For this study, two quarter scale model dams were built at the USDA-ARS Hydraulic Engineering Research Unit in Stillwater, OK. These dams were constructed with two internal compromised zones that would be susceptible to seepage and piping. The zones consist of a sandy region and a region compacted at lower moisture content. Time lapse seismic refraction and electrical resistivity measurements were conducted over a course of two years to monitor changes in the internal structure of the model dams due to seasonal changes, cyclic loadings and internal erosion failure. The results will provide an insight on how compromised zones due to seepage and piping can be identified at an early stage using both SRT and ERT time-lapse measurements and how joint interpretation of these two methods helps in closely identifying what attributed to the compromised zone. [This research was funded by the department of Homeland Security- sponsored Southeast Region Research Initiative (SERRI) at the Department of Energy's Oak Ridge National Laboratory.

  7. 2. East side of lower dam shown with water flowing ...

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

    2. East side of lower dam shown with water flowing over dam. VIEW WEST - Loleta Recreation Area, Lower Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  8. 14. VIEW OF DAM SITE, LOOKING SOUTH (DOWNSTREAM). MIXING PLANT ...

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

    14. VIEW OF DAM SITE, LOOKING SOUTH (DOWNSTREAM). MIXING PLANT IS VISIBLE AT RIGHT, COFFER DAM IS UPSTREAM OF PLACING TOWER. EAST DOME IS VISIBLE AT LEFT OF TOWER, c. 1927 - Coolidge Dam, Gila River, Peridot, Gila County, AZ

  9. 6. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING ...

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

    6. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  10. 5. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING ...

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

    5. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  11. 4. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING NORTHEAST ...

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

    4. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING NORTHEAST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  12. 3. OVERALL VIEW OF DAM, SHOWING UPSTREAM FACE, LOOKING EAST ...

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

    3. OVERALL VIEW OF DAM, SHOWING UPSTREAM FACE, LOOKING EAST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  13. 75 FR 50777 - Minidoka Dam Spillway Replacement, Minidoka County, ID

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ...INT-FES 10-43] Minidoka Dam Spillway Replacement, Minidoka...FEIS on the proposed Minidoka Dam Spillway Replacement. The U.S. Fish and Wildlife Service (Department...submitted electronically to minidoka_dam_eis@usbr.gov. FOR...

  14. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Rubber dam and accessories. 872.6300 Section... Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

  15. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Rubber dam and accessories. 872.6300 Section... Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device...

  16. Dam located to east of powerhouse, view from south. This ...

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

    Dam located to east of powerhouse, view from south. This dam holds back the waters of the Chattahoochee River to form the mill pond north of Riverdale Cotton Mill - Riverdale Cotton Mill, Powerhouse & Dam, Valley, Chambers County, AL

  17. 3. VIEW, LOOKING NORTHEAST, SHOWING A SMALL FIELDSTONE DAM (KNOWN ...

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

    3. VIEW, LOOKING NORTHEAST, SHOWING A SMALL FIELD-STONE DAM (KNOWN LOCALLY AS DAM NO. 2), BUILT BY THE CCC - J. Clark Salyer National Wildlife Refuge Dams, Along Lower Souris River, Kramer, Bottineau County, ND

  18. 8. VIEW OF DAM 83, SHOWING OLD SOURIS RIVER CHANNEL ...

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

    8. VIEW OF DAM 83, SHOWING OLD SOURIS RIVER CHANNEL FROM THE DOWNSTREAM FACE OF THE DAM WITH POND A IN THE BACKGROUND, LOOKING SOUTH - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

  19. 4. VIEW, LOOKING SOUTHWEST, SHOWING A LARGE FIELDSTONE DAM (KNOWN ...

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

    4. VIEW, LOOKING SOUTHWEST, SHOWING A LARGE FIELD-STONE DAM (KNOWN LOCALLY AS DAM NO. 1), BUILT BY THE CCC - J. Clark Salyer National Wildlife Refuge Dams, Along Lower Souris River, Kramer, Bottineau County, ND

  20. 56. LOCK AND DAM NO. 26 (REPLACEMENT). AUXILIARY LOCK AND ...

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

    56. LOCK AND DAM NO. 26 (REPLACEMENT). AUXILIARY LOCK AND REMAINDER OF DAM -- CONCRETE MONOLITH PLAN AND WALL ELEVATIONS (WITH LOCK APPURTENANCES). Drawing V-601 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

  1. GENERAL VIEW OF THE WILSON DAM, LOOKING SOUTHEAST, GENERATING PLANT ...

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

    GENERAL VIEW OF THE WILSON DAM, LOOKING SOUTHEAST, GENERATING PLANT IN THE BACKGROUND. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  2. 5. DETAIL VIEW OF DAM, SHOWING ROLLER AND TAINTER GATES, ...

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

    5. DETAIL VIEW OF DAM, SHOWING ROLLER AND TAINTER GATES, GATE PIERS, HEADHOUSES AND DAM BRIDGE, LOOKING NORTHWEST, UPSTREAM - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 9, Lynxville, Crawford County, WI

  3. 7. DETAIL VIEW OF DAM, SHOWING ROLLER GATES, GATE PIERS, ...

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

    7. DETAIL VIEW OF DAM, SHOWING ROLLER GATES, GATE PIERS, HEADHOUSES AND DAM BRIDGE, LOOKING NORTHWEST, UPSTREAM - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 9, Lynxville, Crawford County, WI

  4. Fragility Analysis of Concrete Gravity Dams

    NASA Astrophysics Data System (ADS)

    Tekie, Paulos B.; Ellingwood, Bruce R.

    2002-09-01

    Concrete gravity dams are an important part ofthe nation's infrastructure. Many dams have been in service for over 50 years, during which time important advances in the methodologies for evaluation of natural phenomena hazards have caused the design-basis events to be revised upwards, in some cases significantly. Many existing dams fail to meet these revised safety criteria and structural rehabilitation to meet newly revised criteria may be costly and difficult. A probabilistic safety analysis (PSA) provides a rational safety assessment and decision-making tool managing the various sources of uncertainty that may impact dam performance. Fragility analysis, which depicts fl%e uncertainty in the safety margin above specified hazard levels, is a fundamental tool in a PSA. This study presents a methodology for developing fragilities of concrete gravity dams to assess their performance against hydrologic and seismic hazards. Models of varying degree of complexity and sophistication were considered and compared. The methodology is illustrated using the Bluestone Dam on the New River in West Virginia, which was designed in the late 1930's. The hydrologic fragilities showed that the Eluestone Dam is unlikely to become unstable at the revised probable maximum flood (PMF), but it is likely that there will be significant cracking at the heel ofthe dam. On the other hand, the seismic fragility analysis indicated that sliding is likely, if the dam were to be subjected to a maximum credible earthquake (MCE). Moreover, there will likely be tensile cracking at the neck of the dam at this level of seismic excitation. Probabilities of relatively severe limit states appear to be only marginally affected by extremely rare events (e.g. the PMF and MCE). Moreover, the risks posed by the extreme floods and earthquakes were not balanced for the Bluestone Dam, with seismic hazard posing a relatively higher risk.

  5. The geomagnetic tail

    SciTech Connect

    Birn, J. )

    1991-01-01

    A review is presented of the plasma sheet and lobe regions of the magnetotail, focusing principally on large-scale processes or microprocesses with some large-scale effects. Consideration is given to quiet and average structures, not necessarily related to activity phases, with quasi-steady convection aspects, and with the characteristics of dynamic phases including acceleration mechanisms and single particle aspects. Attention is given to various activity models, average and quiet time properties, properties and effects of magnetospheric convection, dynamics of the magnetotail, and the near tail, substorm current wedge.

  6. Kidney (Renal) Failure

    MedlinePLUS

    ... News Physician Resources Professions Site Index A-Z Kidney Failure Kidney failure, also known as renal failure, ... evaluated? How is kidney failure treated? What is kidney (renal) failure? The kidneys are designed to maintain ...

  7. Heart failure - overview

    MedlinePLUS

    CHF; Congestive heart failure; Left-sided heart failure; Right-sided heart failure - Cor pulmonale; Cardiomyopathy - heart failure ... Heart failure is often a long-term (chronic) condition, but it may come on suddenly. It can ...

  8. Experiments in dam removal, sediment pulses and channel evolution on the Clark Fork River, MT and White Salmon River, WA

    NASA Astrophysics Data System (ADS)

    Wilcox, A. C.

    2012-12-01

    Two recent dam removals on tributaries to the Columbia River in the northwestern United States present contrasting examples of how dam removal methods, reservoir contents, and geomorphic settings influence system responses. The 2008 removal of Milltown Dam, from the Clark Fork River (CFR), Montana, and the 2011 removal of Condit Dam from the White Salmon River (WSR), Washington (Table 1), represent two of the largest dam removals to date. The Milltown Dam removal was notable because the dam stored millions of cubic meters of contaminated mine tailings, a portion of which were excavated as part of Superfund remediation but a portion of which flowed downstream after the removal. On the CFR, post-breach high flows in 2008 produced reservoir erosion and downstream deposition in bed interstices, along bars, and on the floodplain, but above-average (3-15 year recurrence interval) floods since then have remobilized this material and have, to a large extent, erased signs of downstream sedimentation. The Condit Dam removal entailed dynamiting of a 4m by 5.5m hole at the base of the dam, which produced rapid and dramatic draining of fine reservoir sediments within hours of the blast. Downstream of Condit Dam, the initial hyperconcentrated flows and sediment pulse draped the WSR with fine sediment, filled pools, and, in an unconfined reach influenced by the Columbia River's backwater, caused meters of aggradation and new bar formation. In the confined, bedrock-dominated reach downstream of the Condit site, pool-riffle structure has started to reemerge as of summer 2012 and the finest bed materials have been evacuated from the main channel, although sediment storage in pools and eddies persists. Whereas post-breach geomorphic responses on the CFR have been largely driven by hydrology, the post-breach evolution of the WSR has been predominantly influenced by antecedent geomorphic conditions (slope, confinement, and Columbia River backwater). On both the CFR and WSR, the pace of post-breach reservoir erosion and of geomorphic recovery from the disturbances produced by dam removal has been rapid, far exceeding pre-breach predictions.Table 1: Comparison of Milltown and Condit Dam removals

  9. McNary Dam, Ice Harbor Dam, and Lower Monumental Dam Smolt Monitoring Program; 1996 Annual Report.

    SciTech Connect

    Hillson, Todd; Lind, Sharon; Price, William

    1997-07-01

    The Washington Department of Fish & Wildlife (WDFW) assumed responsibility for the Smolt Monitoring Program at McNary Dam on the Columbia River in 1990 and at the new juvenile collection facility at Lower Monumental Dam on the Snake River in 1993. In 1996, Smolt Monitoring Program activities also began at the new juvenile collection facility located at Ice Harbor Dam. This report summarizes the 1996 Smolt Monitoring work at all three sites. The work at Ice Harbor consisted of Gas Bubble Trauma (GBT) monitoring only. In general, the 1996 passage season at both the McNary and Lower Monumental sites can be characterized by reduced passage of juveniles through the collection systems due to elevated river flows and spill, and low (<1%) overall facility mortality rates most likely resulting from cooler water temperatures. In accordance with the National Marine Fisheries Service recommendations (NMFS, 1995) all spring migrants were bypassed at McNary Dam in 1996. Mechanical problems within the McNary collection system resulted in collection and sampling activities being delayed until April 18 at this site, while sampling and collection began on the scheduled starting date of April 1 at Lower Monumental Dam. Monitoring operations were conducted through December 14 at McNary Dam and through October 28 at Lower Monumental Dam. An ongoing transportation evaluation summer migrant marking program was conducted at McNary Dam in 1996 by the NMFS. This necessitated the sampling of 394,211 additional fish beyond the recommended sampling guidelines. All total, 509,237 and 31,219 juvenile salmonids were anesthetized and individually counted, examined for scale loss, injuries, and brands by WDFW Smolt Monitoring personnel in 1996 at McNary Dam and Lower Monumental Dam, respectively.

  10. Respiratory Failure

    MedlinePLUS

    ... ribs around the lungs. An injury to the chest can cause this damage. Drug or alcohol overdose Injuries from inhaling smoke or harmful fumes Treatment for respiratory failure depends on whether the condition is acute (short-term) or chronic (ongoing) and how severe ...

  11. Tiger Dams Reinforce Baton Rouge Levees

    USGS Multimedia Gallery

    Tiger Dams line the Baton Rouge Mississippi River levee during the 2011 Flood.  Previously used to prevent oil from reaching Louisiana's coast during the 2010 Deepwater Horizon oil spill, these Tiger Dams are filled with water and reinforced with sandbags to give the Baton Rouge Mississippi Riv...

  12. Wenatchee Subbasin Plan EFFECTS OF HYDROELECTRIC DAMS

    E-print Network

    on the performance of salmon populations. Typically PIT-tagged hatchery fish or a mixture of hatchery and wild fish incurred passing the dam and that within the reservoir. Predation on smolts by fish and birds1 Appendix C Wenatchee Subbasin Plan EFFECTS OF HYDROELECTRIC DAMS ON VIABILITY OF WILD FISH Bio

  13. 75 FR 62024 - Metal and Nonmetal Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... Safety and Health Administration 30 CFR Parts 56 and 57 RIN 1219-AB70 Metal and Nonmetal Dams AGENCY... measures to assure that metal and nonmetal mine operators design, construct, operate and maintain dams in a.... ADDRESSES: Comments must be clearly identified and may be submitted by any of the following methods:...

  14. USDA earthen embankment dams: Defining the problem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is estimated that there on the order of 2 to 9 million earthen dams in this country with 80,000 large or significant enough to be placed on the National Inventory of Dams (NID). This is an infrastructure that has significant issues related to: aging components; sedimentation; and changing hydrol...

  15. Perpetuities with thin tails revisited

    E-print Network

    Hitczenko, Pawe?; 10.1214/09-AAP603

    2009-01-01

    We consider the tail behavior of random variables $R$ which are solutions of the distributional equation $R\\stackrel{d}{=}Q+MR$, where $(Q,M)$ is independent of $R$ and $|M|\\le 1$. Goldie and Gr\\"{u}bel showed that the tails of $R$ are no heavier than exponential and that if $Q$ is bounded and $M$ resembles near 1 the uniform distribution, then the tails of $R$ are Poissonian. In this paper, we further investigate the connection between the tails of $R$ and the behavior of $M$ near 1. We focus on the special case when $Q$ is constant and $M$ is nonnegative.

  16. The Impact of Dam-Reservoir-Foundation Interaction on Nonlinear Response of Concrete Gravity Dams

    NASA Astrophysics Data System (ADS)

    Amini, AliReza; Motamedi, Mohammad Hossein; Ghaemian, Mohsen

    2008-07-01

    To study the impact of dam-reservoir-foundation interaction on nonlinear response of concrete gravity dams, a two-dimensional finite element model of a concrete gravity dam including the dam body, a part of its foundation and a part of the reservoir was made. In addition, the proper boundary conditions were used in both reservoir and foundation in order to absorb the energy of outgoing waves at the far end boundaries. Using the finite element method and smeared crack approach, some different seismic nonlinear analyses were done and finally, we came to a conclusion that the consideration of dam-reservoir-foundation interaction in nonlinear analysis of concrete dams is of great importance, because from the performance point of view, this interaction significantly improves the nonlinear response of concrete dams.

  17. The Impact of Dam-Reservoir-Foundation Interaction on Nonlinear Response of Concrete Gravity Dams

    SciTech Connect

    Amini, Ali Reza; Motamedi, Mohammad Hossein; Ghaemian, Mohsen

    2008-07-08

    To study the impact of dam-reservoir-foundation interaction on nonlinear response of concrete gravity dams, a two-dimensional finite element model of a concrete gravity dam including the dam body, a part of its foundation and a part of the reservoir was made. In addition, the proper boundary conditions were used in both reservoir and foundation in order to absorb the energy of outgoing waves at the far end boundaries. Using the finite element method and smeared crack approach, some different seismic nonlinear analyses were done and finally, we came to a conclusion that the consideration of dam-reservoir-foundation interaction in nonlinear analysis of concrete dams is of great importance, because from the performance point of view, this interaction significantly improves the nonlinear response of concrete dams.

  18. State of the marine environment at Little Bay Arm, Newfoundland and Labrador, Canada, 10 years after a "do nothing" response to a mine tailings spill.

    PubMed

    Veinott, Geoff; Sylvester, Paul; Hamoutene, Dounia; Anderson, M Robin; Meade, Jim; Payne, Jerry

    2003-08-01

    In 1989, the tailings pond dam at the site of a former copper mine near Little Bay, Newfoundland and Labrador, Canada, ruptured and tailings spilled into Little Bay Arm. At the time, no action was taken to arrest the flow of tailings or to mitigate the effects of the spill. To date, no action has been taken to repair the dam and tailings continue to flow into Little Bay Arm. As a result, the marine environment around Little Bay Arm has become contaminated with heavy metals from the tailings. However, the tailings are not the only source of heavy metals to the ecosystem. An old slag heap and what is presumably concentrated copper ore spilled during the loading of ore freighters, are also contributing to the ecosystem's metal load. Marine sediment throughout the Arm contained elevated concentrations of Cu, Ni, Zn, As, V, Co, and Mn. Beach material also contained elevated concentrations of metals with material near the slag heap being the most contaminated. At this site, Cu concentrations were in excess of 5000 mg kg(-1) dry weight, Zn greater than 3000 mg kg(-1) and Co concentrations exceeded 700 mg kg(-1). The highest concentrations of metals in biota were found near the slag heap, near the tailings dam breach, and at the site of the former concentrate loading dock. Despite elevated metal concentrations, the tailings and nearby sediment were not devoid of life. Bivalves and seaweed were abundant in the area and there were no obvious signs of tissue damage or disease in soft shell clams (Mya arenaria) living in the tailings. These clams may be suffering from chronic exposure to the tailings, however, evidence of lipid peroxidation in the clams was inconclusive. PMID:12948239

  19. Dam monitoring with fiber optics deformation sensors

    NASA Astrophysics Data System (ADS)

    Kronenberg, Pascal; Casanova, Nicoletta; Inaudi, Daniele; Vurpillot, Samuel

    1997-05-01

    The monitoring of dams represents an important task in the management of hydroelectric systems. Their economic, social and environmental value imposes to know well the real behavior of the structure and its foundations. This paper shows in two practical cases the possibility to improve the quality of deformation measurements by an appropriate fiber optics sensor network. The first case is a study showing the technical and economical feasibility to install an extended, spatial fiber optics deformation sensor network to detect the relative deflection of an entire shell dam. At this purpose of theoretical study has been evaluated on the base of typical load situations with their effective deflections on the Schiffenen dam, a shell-shaped concrete structure near Fribourg. The second case concerns the development and realization of two long fiber optics deformation sensors anchored in the rock to monitor the displacement of the dam relatively to its underground. These sensors have been installed in the Emosson shell dam.

  20. Do we need construct more dams?

    NASA Astrophysics Data System (ADS)

    Chen, J.; Shi, H.

    2013-12-01

    This paper reviews global dam development in association with the growths of global population, economy, and energy consumption in the past several decades, and also evaluates contributions of dam development to future world sustainable development. Eventually, this paper answers whether we need more dams in the future or not. The world population has rapidly increased from 1.6 billion in 1900, 2.5 billion in 1950, 6.1 billion in 2000, to 7.0 billion in 2011, and is projected to reach 9.5 billion in 2050; similarly, the world economy has dramatically expanded. To maintain socioeconomic development, the consumption of water, food and energy has increased rapidly as well. However, the total volume of available water resource over the world is limited, the food production largely depends on water supply, and the main energy sources are still oil, coal and gas at present, which are regarded as non-renewable resources. Accordingly, it is expected that we will face serious problems to deal with the challenges of water crisis, food security and energy shortage in the near future. In order to enhance the capability of regulating water resource, a great number of global dams (and related reservoirs) have been constructed in the last one hundred years; currently, almost all large rivers over the world have been regulated by dams. The reservoirs can supply sufficient water for irrigated land to ensure food production, and the associated hydropower stations can generate electricity. This article collects the dam data from the ICOLD (International Commission on Large Dams) and GRanD (Global Reservoir and Dam) databases, and some socioeconomic data, including population, economy, and consumptions of water, food and energy over the world. Analysis of these data reveals that global dam development has a great impact on the world sustainable development. Further, it is concluded that we need further dam development to maintain our future development.

  1. Automating stability analysis for concrete gravity dams

    SciTech Connect

    Barrett, P.R. ); Morris, D.I.

    1993-06-01

    In an effort to get more realistic stability results, dam owners-with FERC's encouragement-began using actual data collected at their structures in dam safety analyses in the mid-1980s. However, making use of the data was not always easy. The conventional cracked-base analysis method cannot take into account the effects of the dam and foundation stiffnesses. General finite-element software programs for determining dam stability using site-specific data were available, but required a great deal of manipulation, expertise, and time. In early 1987, representatives of utilities, consulting firms, FERC, and federal hydropower producers serving on an Electric Power Research Institute (EPRI) dam safety advisory committee agreed that a special computer code was needed to bridge the gap between traditional analytical practices and finite-element methods. Consequently, EPRI funded ANATECH Research Corp., a consulting engineer firm in San Diego, California, to develop CG-DAMS. This two-dimensional, finite-element computer code automates the stability analysis process. The menu-driven software prompts the user for input of a specific structure's geometry, loading (using input commands such as reservoir and tailwater elevations), and site-specific material properties in the dam and foundation. The results of the analysis are illustrated in easy-to-use graphical and tabular formats, and can be used to predict crack growth, shear, and normal stresses under normal loading, flood loading, and seismic loading. Although CG-DAMS was designed to respond to FERC's dam stability analysis requirements, it can be useful to any dam owner wanting to make more realistic stability assessments than the conventional cracked-base method that reflect site-specific conditions.

  2. Detecting fluid leakage of a reservoir dam based on streaming self-potential measurements

    NASA Astrophysics Data System (ADS)

    Song, Seo Young; Kim, Bitnarae; Nam, Myung Jin; Lim, Sung Keun

    2015-04-01

    Between many reservoir dams for agriculture in suburban area of South Korea, water leakage has been reported several times. The dam under consideration in this study, which is located in Gyeong-buk, in the south-east of the Korean Peninsula, was reported to have a large leakage at the right foot of downstream side of the reservoir dam. For the detection of the leakage, not only geological survey but also geophysical explorations have been made for precision safety diagnosis, since the leakage can lead to dam failure. Geophysical exploration includes both electrical-resistivity and self-potential surveys, while geological surveys water permeability test, standard penetration test, and sampling for undisturbed sample during the course of the drilling investigation. The geophysical explorations were made not only along the top of dam but also transverse the heel of dam. The leakage of water installations can change the known-heterogeneous structure of the dam body but also cause streaming spontaneous (self) potential (SP) anomaly, which can be detected by electrical resistivity and SP measurements, respectively. For the interpretation of streaming SP, we used trial-and-error method by comparing synthetic SP data with field SP data for model update. For the computation, we first invert the resistivity data to obtain the distorted resistivity structure of the dam levee then make three-dimensional electrical-resistivity modeling for the streaming potential distribution of the dam levee. Our simulation algorithm of streaming SP distribution based on the integrated finite difference scheme computes two-dimensional (2D) SP distribution based on the distribution of calculated flow velocities of fluid for a given permeability structure together with physical properties. This permeability is repeatedly updated based on error between synthetic and field SP data, until the synthetic data match the field data. Through this trial-and-error-based SP interpretation, we locate the leakage of reservoir-water formed locally inside the levee body of the reservoir dam within the limitation due to the 2D nature of stream SP simulation.

  3. Heart Failure Cardiovascular Features of Heart Failure

    E-print Network

    Morrell, Christopher H.

    Heart Failure Cardiovascular Features of Heart Failure With Preserved Ejection Fraction Versus of patients with heart failure with preserved ejection fraction (HFpEF) that differ from those in individuals failure. Background Heart failure with preserved ejection fraction often develops in HLVH patients

  4. Metallization failures

    NASA Technical Reports Server (NTRS)

    Beatty, R.

    1971-01-01

    Metallization-related failure mechanisms were shown to be a major cause of integrated circuit failures under accelerated stress conditions, as well as in actual use under field operation. The integrated circuit industry is aware of the problem and is attempting to solve it in one of two ways: (1) better understanding of the aluminum system, which is the most widely used metallization material for silicon integrated circuits both as a single level and multilevel metallization, or (2) evaluating alternative metal systems. Aluminum metallization offers many advantages, but also has limitations particularly at elevated temperatures and high current densities. As an alternative, multilayer systems of the general form, silicon device-metal-inorganic insulator-metal, are being considered to produce large scale integrated arrays. The merits and restrictions of metallization systems in current usage and systems under development are defined.

  5. Modeling an ancient Iranian dam system

    NASA Astrophysics Data System (ADS)

    Ertsen, Maurits; De Schacht, Tijs

    2013-04-01

    In Iran, along the northern and eastern fringes of the Pasargadae plain, five dam remains from the Achaemenid period (550-330 BCE) present an important footprint of the human impact and reshaping of the region. The dams are predominantly found in dry wadi beds. In the framework of the Joint Iranian-French Archaeological Project at Pasargadae, these dam sites were studied and excavated. Located 22 km to the north of Pasargadae in a small wadi, the Sad-i Didegan dam has a watershed of circa 46 square km, small compared with catchments of other known Achaemenid dams. It is an earth built gravity dam of circa 90 m wide, 21 m high and with a crown length of about 150 m. In the lower body of the dam, remains of a feeder canal and an accessible control infrastructure at the downstream flank of the dam were found. To the northwest, the dam site of Sad-i Shahidabad can be found, another large Achaemenid dam, which stored water from the perennial river of the Rud-i Polvar. This dam also had a similar canal and control structure. Close to the Sad-i Didegan area is a large earthwork, found to cross the watershed divide between Didegan and Shahidabad, consisting of a wide V-shaped trench of remarkable size: up to 100 m wide, a total length of at least 900 m and a maximum present day depth of 7.5 m. Even though the construction of the system in this case clearly was left unfinished, the remains echo the major investment of available labor. Given the contemporaneity of both dam sites, it is clear evidence of the more regionally and elaborately planned character of the hydrological endeavors in the Pasargadae area. Only through further study and future fieldwork (also obtaining absolute dating material), this impressive feature will be fully understood. This contribution proposes a possible use of the two dam system using a modern control simulation model. This analysis will also shed light on the question why the system probably never functioned.

  6. Seismic Analysis of Morrow Point Dam

    SciTech Connect

    Noble, C R

    2002-04-01

    The main objective of this study is to perform nonlinear dynamic earthquake time history analyses on Morrow Point Dam, which is located 263 km southwest of Denver, Colorado. This project poses many significant technical challenges, one of which is to model the entire Morrow Point Dam/Foundation Rock/Reservoir system which includes accurate geology topography. In addition, the computational model must be initialized to represent the existing dead loads on the structure and the stress field caused by the dead loads. To achieve the correct dead load stress field due to gravity and hydrostatic load, the computer model must account for the manner in which the dams were constructed. Construction of a dam finite element model with the correct as-built geometry of the dam structure and simply ''turning on'' gravity in the computer model will generally lead to an incorrect initial stress field in the structure. The sequence of segmented lifts typical of dam construction has a significant impact on the static stress fields induced in the dam. In addition, the dam model must also account for the interaction between the adjacent dam segments across the dam contraction joints. As a result of these challenges, it was determined that a significant amount of code development was required in order to accurately simulate the motion of the dam structure. Modifications to the existing slide surfaces are needed to allow for appropriate modeling of the shear keys across the contraction joints. Furthermore, a model for hydrodynamic interaction was also implemented into NIKE3D and DYNA3D for fluid representation in the 3D dam system finite element model. Finally, the modeling of the 3D dam system results in a very large computational model, which makes it difficult to perform a static initialization using an implicit code. Traditionally, for these large models, the model has been initialized over a long time scale using an explicit code. However, recent advancements have made it possible to run NIKE3D in ''parallel'' on relatively small parallel machines as well as on the ASCI platforms.

  7. CG-DAMS: Concrete gravity dam stability analysis software. Application manual, final report

    SciTech Connect

    Not Available

    1993-01-01

    CG-DAMS is a finite element based program written specifically for the stability analysis of concrete gravity dams. The code automates the prediction and evaluation of cracking in the dam, along the dam-rock interface, and in the foundation using incremental nonlinear analysis techniques based on the ``smeared crack`` approach. Its primary application is in the computation of dam-rock interface sliding stability factors of safety. The automated procedure for crack propagation analysis replaces the trial-and-error cracked-base analysis method commonly used in gravity dam safety analyses. This Application manual of CG-DAMS illustrates, through sample problems, the many features of the software. Example problems illustrate the capabilities of both CG-DAMS-PC and CG-DAMS-ABAQUS. CG-DAMS-PC is a menu driven program that runs on 386/486 PCs under the DOS operating system (4 Megabytes RAM, 25 Megabytes of hard disk space). CG-DAMS-ABAQUS is a pre- and post-processor along with a concrete constitutive model and distributed load module that interfaces with the ABAQUS general purpose finite element program. The PC program contains thermal analysis capabilities, a rough crack constitutive model, and an interface to the CRFLOOD software not available with the ABAQUS version. The CG-DAMS-ABAQUS program contains time marching dynamic analysis capabilities not available with the PC program. Example analyses presented include static, pseudo dynamic, and time marching dynamic analyses. The manual also presents sensitivity evaluations on mesh size and foundation material strength. Comparisons are presented between CG-DAMS and gravity method calculations. Comparisons with other finite element software are included for the dynamic time history analyses.

  8. Weighing a dam's economic and environmental impact

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    While some people claim that it was a publicity stunt or criticize it as an economic loss and a move in the wrong direction, the breaching of the low-slung Edwards Dam on July 1 has changed the landscape of the Kennebec River flowing through Augusta, Maine, and may also change the landscape for some other dammed rivers nationwide.The breaching marks the first time that the Federal Energy Regulatory Commission (FERC), which licenses nonfederal hydroelectric projects, has ruled that a dam should be removed because the environmental damage that it causes outweighs its economic benefits.

  9. The role of dams in development.

    PubMed

    Altinbilek, Do?an

    2002-01-01

    Dams are a major issue in sustainable management of finite water resources; they have also become the subject of vigorous public debate. This article considers them in the light of the report of the World Commission on Dams and using the example of Turkey. It is argued that economic development and population growth, particularly in arid and semi-arid regions, make plain the need for dams for hydropower and irrigation. Environmental impact assessment is essential, as are effective programmes for resettlement to avoid the impoverishment of displaced people. PMID:12019817

  10. Trapping efficiency of three types check dams experiment

    NASA Astrophysics Data System (ADS)

    Huang, Hui-Kai; CHEN, Su-Chin; AN, Hsuan-Pei

    2015-04-01

    The check dams constructed to trap debris flow. This study divide check dams into three types as closed-type check dam, slit dam, and modular steel check dam. Closed-type check dam which can trap all kind of sediment or driftwood. Slit check dam is permeable dam, so it can prevent from depositing all of sediment or driftwood. A modular steel check dam improves the existing hard-to-change disadvantages of slit dam structure. The assembling of longitudinal and transverse beams can be constructed independently, and then it could be freely configured to form a flexibly adjustable modular steel check dam. This study used the laws of geometric similitude to design model of dam. To explore the trapping mechanisms and phenomenon in different dismantle transverse beams conditions and compared the trapping efficiency with different type of check dams. This study used different volume ratio with driftwood and sediment. In order to capture the trace of debris flow and calculate accuracy velocity of debris flow the study used several high-speed photography combining the method of 3D Remodeling from Motion Structure with Multi-View Stereo which constructed with multiple photos of overlapping coefficient at least 70% and established three-dimensional system of coordinate in laboratory experiment. As a result, the driftwood deposition rate of modular steel check dam increase 60% than slit dam and 40% than closed-type dam; the debris deposition rate increase 30% than slit dam. In addition, the increment of driftwood volume ratio led to the increment of trapping efficiency of three type of check dams. Meanwhile slit dam is the most effective type in trapping driftwood and sediment with more than 50% of increased rate, because of more driftwood flow through the slit dam jam together easily. Finally, transverse beams which installed the modular steel check dam can suppress the upward movement of driftwood, therefore driftwood can easily form the arched stacking efficiency with transverse beams and enhance the trapping effect.

  11. Rheological investigations of tailings of kimberlite ore dressing and numerical simulation of its behaviour in PLAXIS

    NASA Astrophysics Data System (ADS)

    Korshunov, A.; Nevzorov, A.

    2015-04-01

    The article presents the results of analysis of rheology properties of sandy-clay tailings (wastes) of kimberlite ore dressing of the diamond deposit (Russia, Arkhangelsk region). The coefficient of secondary compression as main parameter of soil's creep is defined by implementing standard one-dimensional consolidation test. The linear correlation between initial void ratio and coefficient of secondary compression of sandy-clay tailings were obtained. For numerical simulation of tailing's behaviour subject to its rheology properties in Soft Soil Creep (SSC) model (time independent behaviour) of PLAXIS software was used. According to laboratory tests calibration of SSC model was implemented. It allows predicting dam's safety and reliability for long-term outlook.

  12. 53. AVALON DAM Photographic copy of historic photo, August ...

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

    53. AVALON DAM - Photographic copy of historic photo, August 9, 1893 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'EDDY DAM. LOOKING EAST.' VIEW OF COLLAPSED DAM - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  13. 46. Photocopy of photograph, c. 1933. VIEW OF DAM AND ...

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

    46. Photocopy of photograph, c. 1933. VIEW OF DAM AND FOREBAY. NOTE ALL WATER FLOWING THROUGH FOREBAY AND OUT EITHER TAILRACE OR SLUICE GATE (INSTEAD OF OVER DAM) BECAUSE OF LOW WATER FLOW. (Courtesy of the Potomac Edison Company Library (Hagerstown, MD), Historical Data Files, Dam No. 5 listing - Dam No. 5 Hydroelectric Plant, On Potomac River, Hedgesville, Berkeley County, WV

  14. 2. Overview of the Lost River Diversion Dam House complex ...

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

    2. Overview of the Lost River Diversion Dam House complex taken from west edge of horseshoe-shaped Lost River Diversion Dam. Interior of east side of dam in the foreground. Facing East. - Klamath Basin Project, Lost River Diversion Dam House, Lost River near intersection of State Highway 140 & Hill Road, Klamath Falls, Klamath County, OR

  15. 7. SOUTHEAST VIEW OF BIG DALTON DAM SHOWING THE MULTIPLE ...

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

    7. SOUTHEAST VIEW OF BIG DALTON DAM SHOWING THE MULTIPLE ARCHES, AN UPSTREAM VIEW OF THE PARAPET WALL ALONG THE CREST OF THE DAM, AND THE SHELTER HOUSE AT THE EAST END OF THE DAM. - Big Dalton Dam, 2600 Big Dalton Canyon Road, Glendora, Los Angeles County, CA

  16. 66. AVALON DAM Photographic copy of historic photo, May ...

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

    66. AVALON DAM - Photographic copy of historic photo, May 22, 1908 (original print filed in Record Group 115, National Archives, Washington, D.C.) W.J.Lubken, photographer 'VIEW LOOKING EAST FROM WEST END OF AVALON DAM, SHOWING DOWNSTREAM FACE OF DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  17. 4. VIEW OF DOWNSTREAM FACE OF DAM, WITH SCARS FROM ...

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

    4. VIEW OF DOWNSTREAM FACE OF DAM, WITH SCARS FROM EARTH MOVING TO CONSTRUCT DAM IN FOREGROUND, LOOKING NORTHWEST - High Mountain Dams in Upalco Unit, Five Point Lake Dam, Ashley National Forest, 12 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

  18. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Diversions at Derby Dam. 418.18 Section 418... and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam...) Increases in canal diversions which would reduce Truckee River flows below Derby Dam by more than 20...

  19. 8. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH ...

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

    8. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH MOVING TO CONSTRUCT DAM, LOOKING NORTH - High Mountain Dams in Upalco Unit, East Timothy Lake Dam, Ashley National Forest, 8.4 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  20. 43. Credit TR. Reconstruction of Dam No. 4 after 1936 ...

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

    43. Credit TR. Reconstruction of Dam No. 4 after 1936 flood. Pouring concrete for new dam section; opening at left for flume to remove water from behind coffer dam. Photo c. 1936 - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  1. 6. DAM AFTERBAY, WITH OWYEE RIVER IN FOREGROUND, SHOWING OUTLET ...

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

    6. DAM AFTERBAY, WITH OWYEE RIVER IN FOREGROUND, SHOWING OUTLET TUNNEL PORTAL (LEFT) AND POWERHOUSE AND ENTRANCE PORTAL TO DAM INTERIOR (RIGHT). NOTE RELEASE OF WATER FROM NEEDLE VALVE NUMBER 2 IN VALVEHOUSE ON DAM. VIEW TO SOUTHEAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  2. Three-Gorges Dam: Risk to Ancient Fish

    E-print Network

    Wu, Jianguo "Jingle"

    Three-Gorges Dam: Risk to Ancient Fish THE HUGETHREE-GORGES DAM (TGD) OFTHE Yangtze River is going and animals, as discussed by J. Wu et al. in their Policy Forum "Three-Gorges Dam-- experiment in habitat). The construction of the Gezhou Dam (38 km downstream from the TGD) in 1981 led to sharp declines in the popula

  3. 9. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH ...

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

    9. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH MOVING TO CONSTRUCT DAM, LOOKING EAST - High Mountain Dams in Upalco Unit, East Timothy Lake Dam, Ashley National Forest, 8.4 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  4. 8. WEST DAM, LOOKING DUE NORTH OVER TOP OF WEST ...

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

    8. WEST DAM, LOOKING DUE NORTH OVER TOP OF WEST DAM, SHOWING RELATIONSHIP BETWEEN OUTLET TO RIGHT OF DAM, NEW PUMP PLANT BUILDING AND CANAL TO LEFT OF DAM. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

  5. Helicopter tail rotor noise analyses

    NASA Technical Reports Server (NTRS)

    George, A. R.; Chou, S. T.

    1986-01-01

    A study was made of helicopter tail rotor noise, particularly that due to interactions with the main rotor tip vortices, and with the fuselage separation mean wake. The tail rotor blade-main rotor tip vortex interaction is modelled as an airfoil of infinite span cutting through a moving vortex. The vortex and the geometry information required by the analyses are obtained through a free wake geometry analysis of the main rotor. The acoustic pressure-time histories for the tail rotor blade-vortex interactions are then calculated. These acoustic results are compared to tail rotor loading and thickness noise, and are found to be significant to the overall tail rotor noise generation. Under most helicopter operating conditions, large acoustic pressure fluctuations can be generated due to a series of skewed main rotor tip vortices passing through the tail rotor disk. The noise generation depends strongly upon the helicopter operating conditions and the location of the tail rotor relative to the main rotor.

  6. [Tail Plane Icing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Aviation Safety Program initiated by NASA in 1997 has put greater emphasis in safety related research activities. Ice-contaminated-tailplane stall (ICTS) has been identified by the NASA Lewis Icing Technology Branch as an important activity for aircraft safety related research. The ICTS phenomenon is characterized as a sudden, often uncontrollable aircraft nose- down pitching moment, which occurs due to increased angle-of-attack of the horizontal tailplane resulting in tailplane stall. Typically, this phenomenon occurs when lowering the flaps during final approach while operating in or recently departing from icing conditions. Ice formation on the tailplane leading edge can reduce tailplane angle-of-attack range and cause flow separation resulting in a significant reduction or complete loss of aircraft pitch control. In 1993, the Federal Aviation Authority (FAA) and NASA embarked upon a four-year research program to address the problem of tailplane stall and to quantify the effect of tailplane ice accretion on aircraft performance and handling characteristics. The goals of this program, which was completed in March 1998, were to collect aerodynamic data for an aircraft tail with and without ice contamination and to develop analytical methods for predicting the effects of tailplane ice contamination. Extensive dry air and icing tunnel tests which resulted in a database of the aerodynamic effects associated with tailplane ice contamination. Although the FAA/NASA tailplane icing program generated some answers regarding ice-contaminated-tailplane stall (ICTS) phenomena, NASA researchers have found many open questions that warrant further investigation into ICTS. In addition, several aircraft manufacturers have expressed interest in a second research program to expand the database to other tail configurations and to develop experimental and computational methodologies for evaluating the ICTS phenomenon. In 1998, the icing branch at NASA Lewis initiated a second multi-phase research program for tailplane icing (TIP II) to develop test methodologies and tailplane performance and handling qualities evaluation tools. The main objectives of this new NASA/Industry/Academia collaborative research programs were: (1) define and evaluate a sub-scale wind tunnel test methodology for determining tailplane performance degradation due to icing. (2) develop an experimental database of tailplane aerodynamic performance with and without ice contamination for a range of tailplane configurations. Wind tunnel tests were planned with representative general aviation aircraft, i.e., the Learjet 45, and a twin engine low speed aircraft. This report summarizes the research performed during the first year of the study, and outlines the work tasks for the second year.

  7. Dam-breach analysis and flood-inundation mapping for Lakes Ellsworth and Lawtonka near Lawton, Oklahoma

    USGS Publications Warehouse

    Rendon, Samuel H.; Ashworth, Chad E.; Smith, S. Jerrod

    2012-01-01

    Dams provide beneficial functions such as flood control, recreation, and reliable water supplies, but they also entail risk: dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or misoperation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. Accurate topographic data are vital for developing flood-inundation maps. This report presents results of a cooperative study by the city of Lawton, Oklahoma, and the U.S. Geological Survey (USGS) to model dam-breach scenarios at Lakes Ellsworth and Lawtonka near Lawton and to map the potential flood-inundation areas of such dam breaches. To assist the city of Lawton with completion of the emergency action plans for Lakes Ellsworth and Lawtonka Dams, the USGS collected light detection and ranging (lidar) data that were used to develop a high-resolution digital elevation model and a 1-foot contour elevation map for the flood plains downstream from Lakes Ellsworth and Lawtonka. This digital elevation model and field measurements, streamflow-gaging station data (USGS streamflow-gaging station 07311000, East Cache Creek near Walters, Okla.), and hydraulic values were used as inputs for the dynamic (unsteady-flow) model, Hydrologic Engineering Center's River Analysis System (HEC-RAS). The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum flood scenario and a sunny-day dam-breach scenario, as well as for maximum flood-inundation elevations and flood-wave arrival times for selected bridge crossings. Some areas of concern near the city of Lawton, if a dam breach occurs at Lakes Ellsworth or Lawtonka, include water treatment plants, wastewater treatment plants, recreational areas, and community-services offices.

  8. 33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). 100.1102 Section... Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). (a) General. Sponsors are... between September and December Where: that portion of Lake Moovalya, Parker, Arizona between Headgate...

  9. 76 FR 34799 - Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN AGENCY... various alternatives for permanent modifications to the existing dam facilities at Cherokee, Fort Loudoun, Tellico, and Watts Bar dams in Tennessee. The level of review will be determined after the public...

  10. 33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Texas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Texas. 208.19 Section 208.19 Navigation and Navigable Waters... Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Texas. In the interest...

  11. EVOLVING EXPECTATIONS OF DAM REMOVAL OUTCOMES: DOWNSTREAM GEOMORPHIC EFFECTS FOLLOWING REMOVAL OF A SMALL, GRAVEL-FILLED DAM1

    E-print Network

    Tullos, Desiree

    EVOLVING EXPECTATIONS OF DAM REMOVAL OUTCOMES: DOWNSTREAM GEOMORPHIC EFFECTS FOLLOWING REMOVAL OF A SMALL, GRAVEL-FILLED DAM1 Kelly Kibler, Desiree Tullos, and Mathias Kondolf 2 ABSTRACT: Dam removal is a promising river restoration technique, particularly for the vast number of rivers impounded by small dams

  12. 78 FR 60271 - Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ...Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer...transferor) and Ampersand Hollow Dam Hydro, LLC (transferee) filed an application...Dam Power Company, c/o SilverStreet Hydro, 15 East Silver Street, Westfield,...

  13. ESTIMATION OF NAVIGATION - DAM DISCHARGE IN ILLINOIS.

    USGS Publications Warehouse

    Weiss, Linda S.

    1987-01-01

    Techniques were used to estimate discharge for the Brandon Road Dam on the Des Plaines River and the Dresden Island, Marseilles, and Starved Rock Dams on the Illinois River in northern Illinois. Tainter gates are operated to regulate streamflow at all dams. Additionally, headgates are used for regulation of the Brandon Road Dam. Stage-discharge, gate-opening relations were developed from a total of 91 discharge measurements that range from 198 to 86,400 cubic feet per second (5. 6 to 2,450 cubic meters per second). Values for discharge coefficients, in equations that express discharge as a function of tailwater depth, headwater depth, and vertical height of gate opening, were determined for conditions of free-orifice, submerged-orifice, free-weir, and submerged-weir flow past a tainter gate.

  14. White Sturgeon Passage at The Dalles Dam

    USGS Publications Warehouse

    U.S. Geological Survey

    2008-01-01

    Researchers at the USGS Western Fisheries Research Center's Columbia River Research Laboratory, working with the U.S. Army Corps of Engineers, sought to better understand upstream and downstream passage of white sturgeon at dams. A study at The Dalles Dam provided the opportunity to compare two fish ladders; one that passes sturgeon upstream to one that does not, to determine if subtle differences in construction result in better passage of white sturgeon. Researchers conducted a study using a combination of acoustic and radio telemetry technologies to obtain information on juvenile and adult white sturgeon near The Dalles Dam, with the objectives of characterizing the distribution and movements of white sturgeon in the immediate vicinity of the dam and to determine timing and routes of upstream and downstream passage.

  15. Numerical modelling of Glacial Lake Outburst Floods using physically based dam-breach models

    NASA Astrophysics Data System (ADS)

    Westoby, M. J.; Brasington, J.; Glasser, N. F.; Hambrey, M. J.; Reynolds, J. M.; Hassan, M. A. A. M.

    2014-06-01

    The rapid development and instability of moraine-dammed proglacial lakes is increasing the potential for the occurrence of catastrophic Glacial Lake Outburst Floods (GLOFs) in high-mountain regions. Advanced, physically-based numerical dam-breach models represent an improvement over existing methods for the derivation of breach outflow hydrographs. However, significant uncertainty surrounds the initial parameterisation of such models, and remains largely unexplored. We use a unique combination of numerical dam-breach and two-dimensional hydrodynamic modelling, employed with a Generalised Likelihood Uncertainty Estimation (GLUE) framework to quantify the degree of equifinality in dam-breach model output for the reconstruction of the failure of Dig Tsho, Nepal. Monte Carlo analysis was used to sample the model parameter space, and morphological descriptors of the moraine breach were used to evaluate model performance. Equifinal breach morphologies were produced by parameter ensembles associated with differing breach initiation mechanisms, including overtopping waves and mechanical failure of the dam face. The material roughness coefficient was discovered to exert a dominant influence over model performance. Percentile breach hydrographs derived from cumulative distribution function hydrograph data under- or overestimated total hydrograph volume and were deemed to be inappropriate for input to hydrodynamic modelling. Our results support the use of a Total Variation Diminishing solver for outburst flood modelling, which was found to be largely free of numerical instability and flow oscillation. Routing of scenario-specific optimal breach hydrographs revealed prominent differences in the timing and extent of inundation. A GLUE-based method for constructing likelihood-weighted maps of GLOF inundation extent, flow depth, and hazard is presented, and represents an effective tool for communicating uncertainty and equifinality in GLOF hazard assessment. However, future research should focus on the utility of the approach for predictive, as opposed to reconstructive GLOF modelling.

  16. Heavy-tailed random matrices

    E-print Network

    Z. Burda; J. Jurkiewicz

    2009-11-08

    We discuss non-Gaussian random matrices whose elements are random variables with heavy-tailed probability distributions. In probability theory heavy tails of the distributions describe rare but violent events which usually have dominant influence on the statistics. They also completely change universal properties of eigenvalues and eigenvectors of random matrices. We concentrate here on the universal macroscopic properties of (1) Wigner matrices belonging to the Levy basin of attraction, (2) matrices representing stable free random variables and (3) a class of heavy-tailed matrices obtained by parametric deformations of standard ensembles.

  17. L018A06010020 rock check dam

    E-print Network

    XY! OMEGA RD. L018A06010020 rock check dam L018A03140017 coir log L018A03140016 coir log L018A established vegetation, green hatch area L018A04030008 rock channel/swale L018A03140012 coir log L018A03140013 coir log L018A03140014 coir log L018A03140011 coir log L018A06010010 rock check dam L018A03010009

  18. Mercury's Dynamic Magnetic Tail

    NASA Technical Reports Server (NTRS)

    Slavin, James A.

    2010-01-01

    The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

  19. Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California

    NASA Astrophysics Data System (ADS)

    Bedrosian, Paul A.; Burton, Bethany L.; Powers, Michael H.; Minsley, Burke J.; Phillips, Jeffrey D.; Hunter, Lewis E.

    2012-02-01

    A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design level have been aborted due to seepage at locations downstream, along the west dam abutment, and at the base of the spillway. In response to these concerns, the U.S. Geological Survey has undertaken a comprehensive suite of geophysical investigations aimed at understanding the interplay between geologic structure, seepage patterns, and reservoir and groundwater levels. This paper concerns the geologic structure surrounding Martis Creek Dam and emphasizes the importance of a regional-scale understanding to the interpretation of engineering-scale geophysical data. Our studies reveal a thick package of sedimentary deposits interbedded with Plio-Pleistocene volcanic flows; both the deposits and the flows are covered by glacial outwash. Magnetic field data, seismic tomography models, and seismic reflections are used to determine the distribution and chronology of the volcanic flows. Previous estimates of depth to basement (or the thickness of the interbedded deposits) was 100 m. Magnetotelluric soundings suggest that electrically resistive bedrock may be up to 2500 m deep. Both the Polaris Fault, identified outside of the study area using airborne LiDAR, and the previously unnamed Martis Creek Fault, have been mapped through the dam area using ground and airborne geophysics. Finally, as determined by direct-current resistivity imaging, time-domain electromagnetic sounding, and seismic refraction, the paleotopography of the interface between the sedimentary deposits and the overlying glacial outwash plays a principal role both in controlling groundwater flow and in the distribution of the observed seepage.

  20. Floodplain Hyporheic Response under Dam Release Hydrographs

    NASA Astrophysics Data System (ADS)

    Zhou, T.; Ward, A. S.; O'Connor, B. L.; Endreny, T. A.

    2012-12-01

    Hydropower operations cause altered hydrograph patterns downstream of dams, which regulates the direction and magnitude of floodplain and riverbed hyporheic flux. Periodic adjustments in river stage changes temporal and spatial patterns in hydraulic pressure, initiates propagation of lateral and vertical hyporheic flux, and affects the riparian ecological system by changing the hyporheic penetration distance, hyporheic flux rate, and thermal conditions in river banks. While this issue has been largely neglected by watershed scientists and managers, there is the potential to use hyporheic metrics in setting dam release rules and restoring downstream river reaches. In order to evaluate the hyporheic feedbacks of various dam release patterns, this study applied a computational fluid dynamics (CFD) model to simulate the interaction of open water hydrographs on porous media lateral hyporheic exchange for the Green River, Utah, downstream of Flaming Gorge Dam. The CFD initially represented the river as a straight channel with a thick porous media extending from the channel banks and bottom. The dam release hydrographs changed the patterns of hyporheic flux at the river banks, the penetration distance of the hyporheic flux, the subsurface thermal patterns, and the residence time of water in the subsurface. The results suggest the undulating river stage downstream of dam releases can initiate patterns of hyporheic exchange similar to those induced by restoration of river bed morphology.

  1. Global phosphorus retention by river damming

    PubMed Central

    Maavara, Taylor; Parsons, Christopher T.; Ridenour, Christine; Stojanovic, Severin; Dürr, Hans H.; Powley, Helen R.; Van Cappellen, Philippe

    2015-01-01

    More than 70,000 large dams have been built worldwide. With growing water stress and demand for energy, this number will continue to increase in the foreseeable future. Damming greatly modifies the ecological functioning of river systems. In particular, dam reservoirs sequester nutrient elements and, hence, reduce downstream transfer of nutrients to floodplains, lakes, wetlands, and coastal marine environments. Here, we quantify the global impact of dams on the riverine fluxes and speciation of the limiting nutrient phosphorus (P), using a mechanistic modeling approach that accounts for the in-reservoir biogeochemical transformations of P. According to the model calculations, the mass of total P (TP) trapped in reservoirs nearly doubled between 1970 and 2000, reaching 42 Gmol y?1, or 12% of the global river TP load in 2000. Because of the current surge in dam building, we project that by 2030, about 17% of the global river TP load will be sequestered in reservoir sediments. The largest projected increases in TP and reactive P (RP) retention by damming will take place in Asia and South America, especially in the Yangtze, Mekong, and Amazon drainage basins. Despite the large P retention capacity of reservoirs, the export of RP from watersheds will continue to grow unless additional measures are taken to curb anthropogenic P emissions. PMID:26644553

  2. Global phosphorus retention by river damming.

    PubMed

    Maavara, Taylor; Parsons, Christopher T; Ridenour, Christine; Stojanovic, Severin; Dürr, Hans H; Powley, Helen R; Van Cappellen, Philippe

    2015-12-22

    More than 70,000 large dams have been built worldwide. With growing water stress and demand for energy, this number will continue to increase in the foreseeable future. Damming greatly modifies the ecological functioning of river systems. In particular, dam reservoirs sequester nutrient elements and, hence, reduce downstream transfer of nutrients to floodplains, lakes, wetlands, and coastal marine environments. Here, we quantify the global impact of dams on the riverine fluxes and speciation of the limiting nutrient phosphorus (P), using a mechanistic modeling approach that accounts for the in-reservoir biogeochemical transformations of P. According to the model calculations, the mass of total P (TP) trapped in reservoirs nearly doubled between 1970 and 2000, reaching 42 Gmol y(-1), or 12% of the global river TP load in 2000. Because of the current surge in dam building, we project that by 2030, about 17% of the global river TP load will be sequestered in reservoir sediments. The largest projected increases in TP and reactive P (RP) retention by damming will take place in Asia and South America, especially in the Yangtze, Mekong, and Amazon drainage basins. Despite the large P retention capacity of reservoirs, the export of RP from watersheds will continue to grow unless additional measures are taken to curb anthropogenic P emissions. PMID:26644553

  3. Tail Risk Measures Heavy-Tail Asymptotics: Regular Variation Multivariate Risks Concluding Remarks Regularly Varying Asymptotics for Tail Risk

    E-print Network

    Li, Haijun

    Tail Risk Measures Heavy-Tail Asymptotics: Regular Variation Multivariate Risks Concluding Remarks Regularly Varying Asymptotics for Tail Risk Haijun Li Department of Mathematics Washington State University Humboldt Univ-Berlin Haijun Li Regularly Varying Asymptotics for Tail Risk Humboldt Univ-Berlin 1 / 26 #12

  4. Unsteady 1D and 2D hydraulic models with ice dam break for Quaternary megaflood, Altai Mountains, southern Siberia

    NASA Astrophysics Data System (ADS)

    Carling, Paul; Villanueva, Ignacio; Herget, Juergen; Wright, Nigel; Borodavko, Pavel; Morvan, Hervé

    2010-02-01

    One of the largest known floods occurred during the Late Quaternary, emanating from an ice-dammed lake in Asia. Glacial lake Kuray-Chuja was formed by a 600-m-high ice dam converging in the Chuja River valley of the Altai Mountains in southern Siberia. The dam impounded up to 594 km 3 of water in the Kuray and Chuja basins. At least three floods from lake Kuray-Chuja occurred, but only the largest, or the most recent, is modelled herein. The discharge, through an ice dam breach by tunnelling or over-topping, is analysed using dam breach equations including one specifically developed for ice dam failures. From these calculations it is concluded that the ice dam need not have failed when the water was at a maximum depth (i.e. 600 m deep) but, in consideration with flood routing models, it is probable that the lake emptied by over-topping under conditions of maximum water level. Although an over-topping model is favoured, a collapse of the ice dam due to initial tunnel development in the ice body cannot be precluded. The resultant flood wave ran down the Chuja River valley to the confluence with the Katun River and beyond. One-dimensional and two-dimensional unsteady and non-uniform flow modelling of the flood wave routed down the river valleys is presented that includes modelling a channel bifurcation at the confluence and backwater effects. The depth of the flood model is constrained by the altitudes of the tops of giant bars deposited by the palaeoflood, which indicate maximum flood stage. The results of the ice dam failure calculations and the flow modelling are independent of each other and are consistent, indicating in each case a flood of the order of 10 M m 3 s - 1 , with best-fit solutions providing estimated peak flood discharges of 9 to 11 M m 3 s - 1 . A breach, 1 km wide and 250 m deep, developed in the ice dam in as little as 11.6 h whereas the flood duration required to evacuate the total lake volume was around 1 day.

  5. Morphogenesis of the T4 tail and tail fibers

    PubMed Central

    2010-01-01

    Remarkable progress has been made during the past ten years in elucidating the structure of the bacteriophage T4 tail by a combination of three-dimensional image reconstruction from electron micrographs and X-ray crystallography of the components. Partial and complete structures of nine out of twenty tail structural proteins have been determined by X-ray crystallography and have been fitted into the 3D-reconstituted structure of the "extended" tail. The 3D structure of the "contracted" tail was also determined and interpreted in terms of component proteins. Given the pseudo-atomic tail structures both before and after contraction, it is now possible to understand the gross conformational change of the baseplate in terms of the change in the relative positions of the subunit proteins. These studies have explained how the conformational change of the baseplate and contraction of the tail are related to the tail's host cell recognition and membrane penetration function. On the other hand, the baseplate assembly process has been recently reexamined in detail in a precise system involving recombinant proteins (unlike the earlier studies with phage mutants). These experiments showed that the sequential association of the subunits of the baseplate wedge is based on the induced-fit upon association of each subunit. It was also found that, upon association of gp53 (gene product 53), the penultimate subunit of the wedge, six of the wedge intermediates spontaneously associate to form a baseplate-like structure in the absence of the central hub. Structure determination of the rest of the subunits and intermediate complexes and the assembly of the hub still require further study. PMID:21129200

  6. 78 FR 53494 - Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... of Dam Structures: Combination of Concrete Floodwalls and Earthen Embankments, will protect the four... Watts Bar). TVA also installed a permanent concrete apron on approximately 2 acres of the downstream...--Permanent Modifications of Dam Structures: Combination of Concrete Floodwalls and Earthen Embankments....

  7. Analysis and dynamic modeling of a moraine failure and glacier lake outburst flood at Ventisquero Negro, Patagonian Andes (Argentina)

    E-print Network

    Butler, David R. - Department of Geography, Texas State University

    Analysis and dynamic modeling of a moraine failure and glacier lake outburst flood at Ventisquero. Georgakakos, Editor-in-Chief, with the assistance of Ehab A. Meselhe, Associate Editor Keywords: Moraine Outburst hydrograph s u m m a r y Although moraine dams are inherently prone to failure because

  8. SUBAQUEOUS DISPOSAL OF MILL TAILINGS

    SciTech Connect

    Neeraj K. Mendiratta; Roe-Hoan Yoon; Paul Richardson

    1999-09-03

    A study of mill tailings and sulfide minerals was carried out in order to understand their behavior under subaqueous conditions. A series of electrochemical experiments, namely, cyclic voltammetry, electrochemical impedance spectroscopy and galvanic coupling tests were carried out in artificial seawater and in pH 6.8 buffer solutions with chloride and ferric salts. Two mill tailings samples, one from the Kensington Mine, Alaska, and the other from the Holden Mine, Washington, were studied along with pyrite, galena, chalcopyrite and copper-activated sphalerite. SEM analysis of mill tailings revealed absence of sulfide minerals from the Kensington Mine mill tailings, whereas the Holden Mine mill tailings contained approximately 8% pyrite and 1% sphalerite. In order to conduct electrochemical tests, carbon matrix composite (CMC) electrodes of mill tailings, pyrite and galena were prepared and their feasibility was established by conducting a series of cyclic voltammetry tests. The cyclic voltammetry experiments carried out in artificial seawater and pH 6.8 buffer with chloride salts showed that chloride ions play an important role in the redox processes of sulfide minerals. For pyrite and galena, peaks were observed for the formation of chloride complexes, whereas pitting behavior was observed for the CMC electrodes of the Kensington Mine mill tailings. The electrochemical impedance spectroscopy conducted in artificial seawater provided with the Nyquist plots of pyrite and galena. The Nyquist plots of pyrite and galena exhibited an inert range of potential indicating a slower rate of leaching of sulfide minerals in marine environments. The galvanic coupling experiments were carried out to study the oxidation of sulfide minerals in the absence of oxygen. It was shown that in the absence of oxygen, ferric (Fe3+) ions might oxidize the sulfide minerals, thereby releasing undesirable oxidation products in the marine environment. The source of Fe{sup 3{minus}} ions may be attributed to iron-bearing sulfide (and oxide) minerals present in the mill tailings. However, the concentration of available Fe{sup 3{minus}} ions can be reduced by the precipitation of insoluble ferric hydroxides (Fe(OH ){sub 3}) by seawater due to its near neutral pH. In such case, the oxidation of a sulfide mineral is inhibited due to the absence of an oxidizing agent (viz. oxygen and/or Fe{sup 3+} ions). The experiments carried out in this study provided a better understanding of behavior of sulfide minerals and mill tailings in subaqueous conditions and may be useful for further investigation of sulfide minerals and mill tailings in other environments.

  9. Field verification of reconstructed dam-break flood, Laurel Run, Pennsylvania

    USGS Publications Warehouse

    Chen, Cheng-lung; Armbruster, Jeffrey T.

    1979-01-01

    A one-dimensional dam-break flood routing model is verified by using observed data on the flash flood resulting from the failure of Laurel Run Reservoir Dam near Johnstown, Pennsylvania. The model has been developed on the basis of an explicit scheme of the characteristics method with specified time intervals. The model combines one of the characteristic equations with the Rankine-Hugoniot shock equations to trace the corresponding characteristic backward to the known state for solving the depth and velocity of flow at the wave front. The previous version of the model has called for a modification of the method of solution to overcome the computational difficulty at the narrow breach and at any geomorphological constraints where channel geometry changes rapidly. The large reduction in the computational inaccuracies and oscillations was achieved by introducing the actual "storage width" in the equation of continuity and the imaginary "conveyance width" in the equation of motion. Close agreement between observed and computed peak stages at several stations downstream of the dam strongly suggests the validity and applicability of the model. However, small numerical noise appearing in the computed stage and discharge hydrographs at the dam site as well as discrepancy of attenuated peaks in the discharge hydrographs indicate the need for further model improvement.

  10. Tail Dependence for Heavy-Tailed Scale Mixtures of Multivariate Distributions

    E-print Network

    Li, Haijun

    Tail Dependence for Heavy-Tailed Scale Mixtures of Multivariate Distributions Haijun Li Yannan Sun September 2009 Abstract The tail dependence of multivariate distributions is frequently studied via the tool, to evaluate the tail dependence of heavy-tailed scale mixtures of multivariate distributions, whose copulas

  11. Tail Mean Estimation is More Efficient than Tail Median: Evidence From the Exponential Power Distribution

    E-print Network

    Pearce, Kent

    Tail Mean Estimation is More Efficient than Tail Median: Evidence From the Exponential Power the relative efficiency of the empirical "tail median" vs. "tail mean" as esti- mators of location under random that the quantile of the untruncated EPD (population tail median) and mean of the left-truncated EPD (population

  12. Concrete dam of the Lenin Dnepr hydroelectric station

    SciTech Connect

    Durcheva, V.N.; Kazachenko, A.N.; Puchkova, S.M.

    1987-01-01

    This paper examines the Dnepr dam, which has been operating for 50 years. The construction of the Dnepr hydroelectric station is described, and the problem of cracking is examined and illustrated. The dam was reconstructed and the characteristics damages of the dam are described. An additional powerhouse was constructed called Dnepr-II. The static behavior of the Dnepr dam is characterized by a thermal stress state of the concrete with extreme values of opening of the joints and of the hydrostatic levels in April and October. The current state of the dam is examined, including seepage through the dam, uplift in the construction joints and uplift in the foundation.

  13. Numerical modelling of glacial lake outburst floods using physically based dam-breach models

    NASA Astrophysics Data System (ADS)

    Westoby, M. J.; Brasington, J.; Glasser, N. F.; Hambrey, M. J.; Reynolds, J. M.; Hassan, M. A. A. M.; Lowe, A.

    2015-03-01

    The instability of moraine-dammed proglacial lakes creates the potential for catastrophic glacial lake outburst floods (GLOFs) in high-mountain regions. In this research, we use a unique combination of numerical dam-breach and two-dimensional hydrodynamic modelling, employed within a generalised likelihood uncertainty estimation (GLUE) framework, to quantify predictive uncertainty in model outputs associated with a reconstruction of the Dig Tsho failure in Nepal. Monte Carlo analysis was used to sample the model parameter space, and morphological descriptors of the moraine breach were used to evaluate model performance. Multiple breach scenarios were produced by differing parameter ensembles associated with a range of breach initiation mechanisms, including overtopping waves and mechanical failure of the dam face. The material roughness coefficient was found to exert a dominant influence over model performance. The downstream routing of scenario-specific breach hydrographs revealed significant differences in the timing and extent of inundation. A GLUE-based methodology for constructing probabilistic maps of inundation extent, flow depth, and hazard is presented and provides a useful tool for communicating uncertainty in GLOF hazard assessment.

  14. Marmot Dam Removal: Predictions and Observations

    NASA Astrophysics Data System (ADS)

    Cui, Y.; Orr, B. K.; Wilcox, A.; Vick, J.; Podolak, C.; Wilcox, P.

    2008-12-01

    The 14-m tall Marmot Dam on the Sandy River, Oregon was removed in the summer of 2007, allowing the approximately 730,000 cubic meters of sand and gravel to remain in the river for natural erosion by the flow. Pre-dam removal studies included sediment transport modeling that simulated several dam removal alternatives and provided key pieces of information that allowed a diverse stakeholder group to unanimously agree on the "blow-and-go" alternative, allowing a large amount of sediment to be released to a major salmonid-bearing river in the Columbia River basin. Although it is still too early to provide a comprehensive evaluation of the model performance because morphological responses in the downstream reaches, if any, are likely years away, observations to date (one year after dam removal) indicate that model predictions are generally accurate. Here we present some of the key findings of pre-dam-removal sediment transport modeling predictions and compare them with post-removal observations.

  15. The Remains of the Dam: What Have We Learned From 10 Years of Dam Removals?

    NASA Astrophysics Data System (ADS)

    Grant, G. E.; O'Connor, J. E.; Major, J. J.

    2012-12-01

    Over the past 10 years in the U.S., dam removal has evolved from an occasionally implemented, rarely studied, and poorly understood intervention to improve rivers, to a much more frequently accomplished and better studied and understood approach to river restoration. Over that same time period, the numbers and sizes of dams and volumes of sediment released have dramatically increased. By some estimates close to 1000 dams have been removed over the last 100 years, with most of those occurring within the last 10. While most of these are small (less than 15 m high) dams, removals of dams up to 70 m high are presently underway. Releases of sediment associated with these removals over the past 10 years have also increased by close to four orders of magnitude; for example removal of the Elwha River dams in Washington is estimated to release almost 107 m3 of sediment into the lower Elwha River. Given a decade's worth of dam removals and, in some cases, well-orchestrated case studies of the effects of removal on the geomorphology and (to a lesser extent) ecology of rivers, what have we learned? More specifically, where do we now stand with respect to being able to predict the consequences of future dam removals? Drawing on both field examples and numerical models of dam removals in the western U.S., several key lessons stand out. Although every dam removal and river are different, removals initiate very rapid upstream river response and reservoir erosion and evacuation of sediment by various mechanisms that are strongly controlled by grain size of the deposit, volumes of residual sediment relative to total reservoir volume, and style of dam removal (instantaneous versus staged). Erosion of sediment accumulations in fully and partially filled (by sediment) reservoirs proceeds by different trajectories and rates, with full reservoirs releasing sediment primarily by upstream knickpoint retreat while erosion and sediment release in partially-filled reservoirs proceeds by vertical incision and delta progradation. Coarse grained non-cohesive sediment deposits erode by both vertical incision and lateral migration; fine-grained non-cohesive deposits can slump and fail catastrophically by landsliding. The rate of upstream reservoir erosion sets the tempo of downstream river adjustments and sedimentation. Prediction of location of sediment accumulations is bolstered by both 1- and 2-D hydrodynamic models that have proven to be remarkably accurate in predicting the spatial extent and pattern of deposition, but are less accurate with respect to predicting timing and longevity of deposits.Erosion of Marmot coffer dam on the Sandy River, OR following dam breach, October 19, 2007

  16. Biological activity of the metal-rich post-flotation tailings at an abandoned mine tailings pond (four decades after experimental afforestation).

    PubMed

    Feketeová, Zuzana; Hulejová Sládkovi?ová, Veronika; Mangová, Barbara; Šimkovic, Ivan

    2015-08-01

    In the spring 2012, post-flotation tailings of the inactive impoundment Lintich (Slovakia) were sampled. In the impoundment sediment and also in its surrounding, we detected concentration of Pb, Zn, Cd, Cu, and Ba exceeding limiting values. We detected low values of the microbial biomass carbon and microbial activity in the impoundment sediment (LiS) and its dam (DAM) along with potential respiration stayed relatively low and therefore also substrate availability index and metabolic quotient (qCO2) were higher in the control sample (REF) than in the LiS and the DAM. The low qCO2 level indicates that microbial community, despite of dangerously high levels of heavy metals in sediment, is still able to sufficiently utilize sources of available organic carbon. Anyway, we could doubt function of the metabolic index as universal indicator of environment conditions, regarding the anthropogenic substrates. We confirmed changes in composition of the mite communities along gradient dam-impoundment. The percentage of eudominant, recendent, and subrecendent species increased at the expense of dominants and subdominants, all together with decreasing diversity and equitability of the community. We identified species Chamobates borealis, Carabodes rugosior, Metabelba propexa, and Pergalumna nervosa with negative respond under the heavy metal stress. Species Adoristes ovatus was indifferent and Dissorhina sp., Hafenrefferia gilvipes, and Oppiella nova prospered under the loaded conditions. Forty years after experimental afforestation, we expect specific community of actively surviving microorganisms and Oribatida species detected in the DAM are usual in the greatly degraded habitats or on sites in the early succession. PMID:25893624

  17. Distribution of trace element pollutants in a contaminated ecosystem established on metalliferous fluorspar tailings. 3: fluoride.

    PubMed

    Andrews, S M; Cooke, J A; Johnson, M S

    1989-01-01

    High total soil fluoride (10 000 microg g(-1)) in the metalliferous fluorspar tailings was reflected by elevated concentrations in standing live vegetation (300-1000 microg g(-1)); plant roots (c. 6000 microg g(-1)); plant litter (c. 4000 microg g(-1)); total body concentrations of invertebrates (400-4000 microg g(-1)) and the small mammals Microtus agrestis (120-360 microg g(-1)) and Sorex araneus (140-250 microg g(-1)). Seasonal changes in the standing live vegetation and the availability of soil fluoride to plants are discussed. Seasonal changes in total body concentrations of the small mammals were related to the age structure of the populations as well as dietary levels. In the small mammals, the concentration ratios were < 0.5 at the tailings dam and > 1.1 at the control site, indicating that both species were able to regulate fluoride accumulation at the higher levels of intake. Soft tissue concentrations were, as expected, very low compared to the hard tissues but, still, were generally significantly higher at the tailings dam compared to the control site. Evidence of dental fluorosis was found in Microtus agrestis, but not Sorex araneus. PMID:15092395

  18. Revised Final Independent External Peer Review Report for the East Branch Dam, Clarion River,

    E-print Network

    US Army Corps of Engineers

    Revised Final Independent External Peer Review Report for the East Branch Dam, Clarion River, Elk County, Pennsylvania: Dam Safety Modification Report Prepared by Battelle Memorial Institute Prepared Report East Branch Dam, Clarion River, Elk County, Pennsylvania: Dam Safety Modification Report

  19. Acute kidney failure

    MedlinePLUS

    Kidney failure; Renal failure; Renal failure - acute; ARF; Kidney injury - acute ... There are many possible causes of kidney damage. They include: ... cholesterol (cholesterol emboli) Decreased blood flow due to very ...

  20. Analysis of deformations of large earth dams

    NASA Astrophysics Data System (ADS)

    Szostak-Chrzanowski, Anna; Massiéra, Michel; Chrzanowski, Adam

    2007-09-01

    Safety of earth dams depends on the proper design, construction, and monitoring of actual behaviour during the construction and during the operation of the structure. The most critical factor in the assessment of the safety threshold value of any structure is the acceleration of its deformation. Therefore, the designed accuracy of monitoring surveys must fulfill requirements of detecting accelerations at critical locations of the investigated object. As an example, time dependant behavior of a large embankment dam during filling up the reservoir has been analyzed and verified by comparing monitoring results with the deterministic (prediction) model of the deformation. The geotechnical and geodetic monitoring besides providing a warning system in case of an abnormal behaviour of the dam, may be used as a tool for a verification of design parameters where geotechnical parameters are of the highest importance. Modeling of deformation of earth dams is a complex process in which one should consider the nonlinear behaviour of the construction material, interaction between the structure and the underlying foundation strata, influence of water load on the structure and on the foundation bedrock, and the effects of water saturation. Due to the uncertainty of the model parameters, careful monitoring of the dam and its surroundings are required in order to verify and enhance the model. In addition, with properly designed monitoring surveys, one may also determine the actual deformation mechanism. The finite element method may be useful tool in the proper design of the monitoring scheme by providing information on the locations and magnitude of the expected maximum displacements and velocites of movements. The discussed problems are illustrated by three types of earth dams located in California, U.S.A. and in Quebec, Canada.

  1. Dam nation: A geographic census of American dams and their large-scale hydrologic impacts

    NASA Astrophysics Data System (ADS)

    Graf, William L.

    1999-04-01

    Newly available data indicate that dams fragment the fluvial system of the continental United States and that their impact on river discharge is several times greater than impacts deemed likely as a result of global climate change. The 75,000 dams in the continental United States are capable of storing a volume of water almost equaling one year's mean runoff, but there is considerable geographic variation in potential surface water impacts. In some western mountain and plains regions, dams can store more than 3 year's runoff, while in the Northeast and Northwest, storage is as little as 25% of the annual runoff. Dams partition watersheds; the drainage area per dam varies from 44 km2 (17 miles2) per dam in New England to 811 km2 (313 miles2) per dam in the Lower Colorado basin. Storage volumes, indicators of general hydrologic effects of dams, range from 26,200 m3 km-2 (55 acre-feet mile-2) in the Great Basin to 345,000 m3 km-2 (725 acre-feet mile-2) in the South Atlantic region. The greatest river flow impacts occur in the Great Plains, Rocky Mountains, and the arid Southwest, where storage is up to 3.8 times the mean annual runoff. The nation's dams store 5000 m3 (4 acre-feet) of water per person. Water resource regions have experienced individualized histories of cumulative increases in reservoir storage (and thus of downstream hydrologic and ecologic impacts), but the most rapid increases in storage occurred between the late 1950s and the late 1970s. Since 1980, increases in storage have been relatively minor.

  2. Optimizing the dammed: water supply losses and fish habitat gains from dam removal in California.

    PubMed

    Null, Sarah E; Medellín-Azuara, Josué; Escriva-Bou, Alvar; Lent, Michelle; Lund, Jay R

    2014-04-01

    Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime and degrading aquatic and riparian habitat. Restoring some rivers reaches to free-flowing conditions may restore substantial environmental benefits, but at some economic cost. This study uses a systems analysis approach to preliminarily evaluate removing rim dams in California's Central Valley to highlight promising habitat and unpromising economic use tradeoffs for water supply and hydropower. CALVIN, an economic-engineering optimization model, is used to evaluate water storage and scarcity from removing dams. A warm and dry climate model for a 30-year period centered at 2085, and a population growth scenario for year 2050 water demands represent future conditions. Tradeoffs between hydropower generation and water scarcity to urban, agricultural, and instream flow requirements were compared with additional river kilometers of habitat accessible to anadromous fish species following dam removal. Results show that existing infrastructure is most beneficial if operated as a system (ignoring many current institutional constraints). Removing all rim dams is not beneficial for California, but a subset of existing dams are potentially promising candidates for removal from an optimized water supply and free-flowing river perspective. Removing individual dams decreases statewide delivered water by 0-2282 million cubic meters and provides access to 0 to 3200 km of salmonid habitat upstream of dams. The method described here can help prioritize dam removal, although more detailed, project-specific studies also are needed. Similarly, improving environmental protection can come at substantially lower economic cost, when evaluated and operated as a system. PMID:24594701

  3. Evaluating the effects of dam breach methodologies on Consequence Estimation through Sensitivity Analysis

    NASA Astrophysics Data System (ADS)

    Kalyanapu, A. J.; Thames, B. A.

    2013-12-01

    Dam breach modeling often includes application of models that are sophisticated, yet computationally intensive to compute flood propagation at high temporal and spatial resolutions. This results in a significant need for computational capacity that requires development of newer flood models using multi-processor and graphics processing techniques. Recently, a comprehensive benchmark exercise titled the 12th Benchmark Workshop on Numerical Analysis of Dams, is organized by the International Commission on Large Dams (ICOLD) to evaluate the performance of these various tools used for dam break risk assessment. The ICOLD workshop is focused on estimating the consequences of failure of a hypothetical dam near a hypothetical populated area with complex demographics, and economic activity. The current study uses this hypothetical case study and focuses on evaluating the effects of dam breach methodologies on consequence estimation and analysis. The current study uses ICOLD hypothetical data including the topography, dam geometric and construction information, land use/land cover data along with socio-economic and demographic data. The objective of this study is to evaluate impacts of using four different dam breach methods on the consequence estimates used in the risk assessments. The four methodologies used are: i) Froehlich (1995), ii) MacDonald and Langridge-Monopolis 1984 (MLM), iii) Von Thun and Gillete 1990 (VTG), and iv) Froehlich (2008). To achieve this objective, three different modeling components were used. First, using the HEC-RAS v.4.1, dam breach discharge hydrographs are developed. These hydrographs are then provided as flow inputs into a two dimensional flood model named Flood2D-GPU, which leverages the computer's graphics card for much improved computational capabilities of the model input. Lastly, outputs from Flood2D-GPU, including inundated areas, depth grids, velocity grids, and flood wave arrival time grids, are input into HEC-FIA, which provides the consequence assessment for the solution to the problem statement. For the four breach methodologies, a sensitivity analysis of four breach parameters, breach side slope (SS), breach width (Wb), breach invert elevation (Elb), and time of failure (tf), is conducted. Up to, 68 simulations are computed to produce breach hydrographs in HEC-RAS for input into Flood2D-GPU. The Flood2D-GPU simulation results were then post-processed in HEC-FIA to evaluate: Total Population at Risk (PAR), 14-yr and Under PAR (PAR14-), 65-yr and Over PAR (PAR65+), Loss of Life (LOL) and Direct Economic Impact (DEI). The MLM approach resulted in wide variability in simulated minimum and maximum values of PAR, PAR 65+ and LOL estimates. For PAR14- and DEI, Froehlich (1995) resulted in lower values while MLM resulted in higher estimates. This preliminary study demonstrated the relative performance of four commonly used dam breach methodologies and their impacts on consequence estimation.

  4. Lac Courte Oreilles Hydro Dam Assessment

    SciTech Connect

    Weaver, Jason; Meyers, Amy

    2014-12-31

    The main objective of this project was to investigate upgrading the existing hydro power generating system at the Winter Dam. The tribe would like to produce more energy and receive a fair market power purchase agreement so the dam is no longer a drain on our budget but a contributor to our economy. We contracted Kiser Hydro, LLC Engineering for this project and received an engineering report that includes options for producing more energy with cost effective upgrades to the existing turbines. Included in this project was a negotiation of energy price sales negotiations.

  5. 504 volume 29 number 6 june 2011 nature biotechnology Turning mouse tails into liver

    E-print Network

    Mayer, Michael

    504 volume 29 number 6 june 2011 nature biotechnology Turning mouse tails into liver Liver transplantation is the only remedy for liver failure, but many people in need of a transplant die awaiting a donor). Starting with 14 transcription factors that are important for liver development, the researchers pared

  6. 2. Salmon Creek Diversion Dam, overview, diversion weir center foreground, ...

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

    2. Salmon Creek Diversion Dam, overview, diversion weir center foreground, headworks overflow weir to center left, view to east - Salmon Creek Diversion Dam, Salmon Creek, Okanogan, Okanogan County, WA

  7. 1. Salmon Creek Diversion Dam, weir (to left), sand and ...

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

    1. Salmon Creek Diversion Dam, weir (to left), sand and silt sluice gate (center), main canal headworks (to right), view to northwest - Salmon Creek Diversion Dam, Salmon Creek, Okanogan, Okanogan County, WA

  8. 12. LOCK, ELECTRICAL SYSTEM, LOCK, DAM, AND NAVIGATION LIGHTING UNITS ...

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

    12. LOCK, ELECTRICAL SYSTEM, LOCK, DAM, AND NAVIGATION LIGHTING UNITS (October 1935) - Mississippi River 9-Foot Channel Project, Lock & Dam No. 18, Upper Mississippi River, Gladstone, Henderson County, IL

  9. 76. LOCK, ELECTRICAL SYSTEM, LOCK, DAM AND NAVIGATION LIGHTING UNITS. ...

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

    76. LOCK, ELECTRICAL SYSTEM, LOCK, DAM AND NAVIGATION LIGHTING UNITS. February 1938 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

  10. 73. GENERAL ASSEMBLY OF MECHANISM, FOR OPERATING DIVERSION DAM SLUICE ...

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

    73. GENERAL ASSEMBLY OF MECHANISM, FOR OPERATING DIVERSION DAM SLUICE GATES Courtesy of U.S.R.S., Salt River Project - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  11. 5. View of upper dam side sluice taken from east ...

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

    5. View of upper dam side sluice taken from east bank of Millstone Creek. VIEW WEST - Loleta Recreation Area, Upper Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  12. 1. East side of lower dam shown with water level ...

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

    1. East side of lower dam shown with water level dropped. VIEW WEST - Loleta Recreation Area, Lower Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  13. 3. Side view of upper dam overspill, taken from east ...

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

    3. Side view of upper dam overspill, taken from east bank of Millstone Creek. VIEW WEST - Loleta Recreation Area, Upper Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  14. 4. Side of view of upper dam overspill, taken from ...

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

    4. Side of view of upper dam overspill, taken from west bank of Millstone Creek, VIEW EAST - Loleta Recreation Area, Upper Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  15. View of upstream face of Grand Coulee Dam, looking northeast. ...

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

    View of upstream face of Grand Coulee Dam, looking northeast. This image features a cloudless sky.) - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  16. 34. DOWNSTREAM VIEW OF COOLIDGE DAM COMPLETED. POWER HOUSE, INTAKE ...

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

    34. DOWNSTREAM VIEW OF COOLIDGE DAM COMPLETED. POWER HOUSE, INTAKE TOWERS, WEST SPILLWAY CHANNEL AND DECORATIVE EAGLES ALL CLEARLY VISIBLE, c. 1928 - Coolidge Dam, Gila River, Peridot, Gila County, AZ

  17. 19. View of low crib dam, headworks, and tramway above ...

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

    19. View of low crib dam, headworks, and tramway above dam, looking southeast. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  18. 2. Distant view of lock and dam to northwest ...

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

    2. Distant view of lock and dam to northwest - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  19. 1. Distant view of lock and dam to northeast ...

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

    1. Distant view of lock and dam to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  20. 3. Down river view of lock and dam to southwest ...

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

    3. Down river view of lock and dam to southwest - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  1. 4. View of dam front and sluiceway outlets Mississippi ...

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

    4. View of dam front and sluiceway outlets - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  2. 2. EASTSIDE RESERVOIR UNDER CONSTRUCTION LOOKING WEST WITH EAST DAM ...

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

    2. EASTSIDE RESERVOIR UNDER CONSTRUCTION LOOKING WEST WITH EAST DAM IN MIDDLE GROUND, WEST DAM IN DISTANCE. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

  3. VIEW FROM NORTH BANK LOOKING SOUTHWEST SHOWING DAM CREST, FISH ...

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

    VIEW FROM NORTH BANK LOOKING SOUTHWEST SHOWING DAM CREST, FISH ATTRACTION FLOW STRUCTURE (LEFT) AND WASTE FLOW GATE OUTLET (RIGHT) - Trout Creek Dam, River Mile 1.8 on Trout Creek, Carson, Skamania County, WA

  4. 3. POOL, DAM, AND INTAKE TO PIPELINE LEADING TO FISH ...

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

    3. POOL, DAM, AND INTAKE TO PIPELINE LEADING TO FISH WHEEL, LOOKING WEST-NORTHWEST. - Santa Ana River Hydroelectric System, Bear Creek Diversion Dam & Confluence Pool, Redlands, San Bernardino County, CA

  5. 32. Otter Lake Dam. View from downstream show how the ...

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

    32. Otter Lake Dam. View from downstream show how the dam blends into its environment. Looking east-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  6. Interior of dam, showing one of the ten bays, looking ...

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

    Interior of dam, showing one of the ten bays, looking west through arched openings along the center of the dam. - Robert B. Morse Water Filtration Plant, 10700 and 10701 Columbia Pike, Silver Spring, Montgomery County, MD

  7. 6. GENERAL CONSTRUCTION VIEW ALONG AXIS OF DAM FROM THE ...

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

    6. GENERAL CONSTRUCTION VIEW ALONG AXIS OF DAM FROM THE EAST ABUTMENT.... Volume XVII, No. 18, December 18, 1939. - Prado Dam, Embankment, Santa Ana River near junction of State Highways 71 & 91, Corona, Riverside County, CA

  8. 2. VIEW EAST OF HEADGATES AT SPOOL DAM; DRAIN GATE ...

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

    2. VIEW EAST OF HEADGATES AT SPOOL DAM; DRAIN GATE MECHANISM AND DAM EDGE AT RIGHT - Willimantic Linen Company, Mill No. 1, Immediately West of South Main Street, North Bank of Willimantic River, Windham, Windham County, CT

  9. 45. Reinforcement work to buttresses at Pleasant Dam. Support work ...

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

    45. Reinforcement work to buttresses at Pleasant Dam. Support work for roadway and roadway visible. Photographer unknown, 1935. Source: Huber Collection. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  10. 71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLEARCHED DAM: STRESS SHEET, SHEET ...

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

    71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLE-ARCHED DAM: STRESS SHEET, SHEET 3; DECEMBER 20, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  11. View of powerhouse and dam from third floor of original ...

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

    View of powerhouse and dam from third floor of original section of Langdale Cotton Mill, looking northeast - Langdale Cotton Mill, Powerhouse & Dam, 5910 Nineteenth Avenue, Valley, Chambers County, AL

  12. 29. VIEW NORTHWEST ON SHELTON SIDE OF DAM DURING DEWATERING. ...

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

    29. VIEW NORTHWEST ON SHELTON SIDE OF DAM DURING DEWATERING. SHELTON GATEHOUSE IN LEFT CENTER. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  13. 10. DETAIL VIEW OF SPILLWAY AT DAM 83, SHOWING RIVER ...

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

    10. DETAIL VIEW OF SPILLWAY AT DAM 83, SHOWING RIVER COBBLE PAVING (FOREGROUND) AND WINGWALL, LOOKING EAST - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

  14. 1. VIEW OF DAM 83, LOOKING SOUTHWEST FROM THE LOOKOUT ...

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

    1. VIEW OF DAM 83, LOOKING SOUTHWEST FROM THE LOOKOUT TOWER AT THE REFUGE HEADQUARTERS (see HAER No. ND-3-A-13 for comparison) - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

  15. 9. VIEW OF SPILLWAY AT DAM 83, SHOWING LOCATION OF ...

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

    9. VIEW OF SPILLWAY AT DAM 83, SHOWING LOCATION OF FORMER CONCRETE FLASHBOARD STRUCTURE ON RIGHT, LOOKING WEST - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

  16. 44. Reinforcement construction to Pleasant Dam. Photographer unknown, 1935. Source: ...

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

    44. Reinforcement construction to Pleasant Dam. Photographer unknown, 1935. Source: Huber Collection, University of California, Berkeley, Water Resources Library. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  17. 9. VIEW OF DAM FROM LEFT SIDE. PUMPCRETE PIPE LINES ...

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

    9. VIEW OF DAM FROM LEFT SIDE. PUMPCRETE PIPE LINES ARE CARRIED ON WALKWAY. UPSTREAM PARTS OF BUTTRESSES ARE FOG-SPRAYED TO PERMIT PROMPT FILLING OF CONTRACTION JOINTS. July 30, 1938 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

  18. 10. Downstream face of Mormon Flat Dam under construction. Cement ...

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

    10. Downstream face of Mormon Flat Dam under construction. Cement storage shed is at center right. Photographer unknown, September 1924. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

  19. 7. CLOSEUP VIEW OF WASHED UP 12' x 12' DAM ...

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

    7. CLOSE-UP VIEW OF WASHED UP 12' x 12' DAM SUPPORT TIMBERS, THREE BEARS LAKE, LOOKING NORTHEAST FROM SOUTH SIDE OF LAKE - Three Bears Lake & Dams, North of Marias Pass, East Glacier Park, Glacier County, MT

  20. 22. VIEW SHOWING THE COMPLETED HORSE MESA DAM, EXCEPT FOR ...

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

    22. VIEW SHOWING THE COMPLETED HORSE MESA DAM, EXCEPT FOR TRANSFORMER EQUIPMENT BEING INSTALLED ABOVE THE POWER PLANT 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  1. 36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER ...

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

    36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER PLANT, LOOKING NORTH. ONLY TWO OF THE THREE UNITS ARE VISIBLE - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  2. 24. CLOSEUP VIEW OF HORSE MESA DAM. HEFU PENSTOCK IS ...

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

    24. CLOSE-UP VIEW OF HORSE MESA DAM. HEFU PENSTOCK IS AT CENTER RIGHT, AND LEFT (OR SOUTH) SPILLWAY CHUTE IS AT UPPER RIGHT - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  3. 23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL ...

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

    23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL AT LEFT, RIGHT (OR NORTH) SPILLWAY, HEFU POWER UNIT, AND ORIGINAL POWER PLANT - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  4. 1. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, VIEW OF NORTH ...

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

    1. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, VIEW OF NORTH ELEVATION OF INTAKE ON EAST SIDE OF DAM - Snake River Valley Irrigation District, East Side of Snake River (River Mile 796), Shelley, Bingham County, ID

  5. Swan Lake Dam: a study in cost saving

    SciTech Connect

    Not Available

    1985-04-01

    The construction of the dam for the Swan Lake hydroelectric project in Alaska is discussed. The hydro project was built for an estimated $4.3 million less than conventional hydro dams of this scope. The project highlights are given.

  6. 75 FR 34476 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-17

    ...Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior...for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and to provide...

  7. 77 FR 22801 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ...Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation...The Glen Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to...advisory committee, the AMWG, a technical work group, a Grand Canyon Monitoring and...

  8. 5. UPSTREAM (WEST) VIEW OF SPILLWAY, WITH COOKE DAM POND ...

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

    5. UPSTREAM (WEST) VIEW OF SPILLWAY, WITH COOKE DAM POND IN FOREGROUND AND NORTH EMBANKMENT (MI-98-A) AT LEFT. VIEW TO NORTHEAST. - Cooke Hydroelectric Plant, Spillway, Cook Dam Road at Au Sable River, Oscoda, Iosco County, MI

  9. 7. Detail view of reinforced concrete archrings comprising dam's upstream ...

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

    7. Detail view of reinforced concrete arch-rings comprising dam's upstream face. Impressions of the wooden formwork used in construction are visible in the concrete. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  10. 5. VIEW SHOWING THE DOWNSTREAM SIDE OF SWAN FALLS DAM ...

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

    5. VIEW SHOWING THE DOWNSTREAM SIDE OF SWAN FALLS DAM AND POWER HOUSE, LOOKING UPSTREAM TO SOUTH FROM THE A MOUND OF DEBRIS ABOUT THIRTY TO FORTY FEET ABOVE THE RIVER - Swan Falls Dam, Snake River, Kuna, Ada County, ID

  11. 7. ISLAND PLANT AND HORSESHOE DAM FROM WEST BANK (negative ...

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

    7. ISLAND PLANT AND HORSESHOE DAM FROM WEST BANK (negative reversed) - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  12. 20. HORSESHOE DAM LOOKING EAST WITH UPPER END DEMOLISHED FOR ...

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

    20. HORSESHOE DAM LOOKING EAST WITH UPPER END DEMOLISHED FOR NEW SPILLWAY (negative reversed) - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  13. 2. OVERALL VIEW OF LOWWATER DAM, LOOKING UPSTREAM. CHAIN OF ...

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

    2. OVERALL VIEW OF LOW-WATER DAM, LOOKING UPSTREAM. CHAIN OF ROCKS BRIDGE AND ST. LOUIS WATER DEPARTMENT INTAKE IN BACKGROUND, LOOKING NORTHWEST - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 27, Granite City, Madison County, IL

  14. 5. DETAIL VIEW OF TOE SPILLWAY SECTION OF LOWWATER DAM, ...

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

    5. DETAIL VIEW OF TOE SPILLWAY SECTION OF LOW-WATER DAM, LOOKING NORTHWEST (UPSTREAM). ST. LOUIS WATER DEPARTMENT INTAKE IN BACKGROUND - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 27, Granite City, Madison County, IL

  15. 68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: STRESS SHEET, SHEET 4; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  16. 77. Plan of Proposed Concrete of Rubble Masonry Dam at ...

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

    77. Plan of Proposed Concrete of Rubble Masonry Dam at Frog Tanks on the Agua Fria River, Arizona. September 1903. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  17. 11. VIEW OF HOCK OUTCROPPING, CONCRETE GRAVITY DAM FACE AND ...

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

    11. VIEW OF HOCK OUTCROPPING, CONCRETE GRAVITY DAM FACE AND LAKE WITH TUNNEL INLET STRUCTURE IN DISTANCE, SHOWN AT MINIMUM WATER FLOW, LOOKING SOUTHEAST (UPSTREAM) - Van Arsdale Dam, South Fork of Eel River, Ukiah, Mendocino County, CA

  18. 12. DETAIL VIEW OF STEPPED CONCRETE GRAVITY DAM FACE AND ...

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

    12. DETAIL VIEW OF STEPPED CONCRETE GRAVITY DAM FACE AND ROCK OUTCROPPING, WITH LAKE IN BACKGROUND, SHOWN AT MINIMUM WATER FLOW, LOOKING SOUTHEAST (UPSTREAM) - Van Arsdale Dam, South Fork of Eel River, Ukiah, Mendocino County, CA

  19. 1. OVERALL VIEW SHOWING FACE OF CONCRETE GRAVITY DAM AND ...

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

    1. OVERALL VIEW SHOWING FACE OF CONCRETE GRAVITY DAM AND FISH LADDER, LOOKING SOUTHWEST (UPSTREAM) FROM SNORE OPPOSITE FISH LADDER - Van Arsdale Dam, South Fork of Eel River, Ukiah, Mendocino County, CA

  20. 21. THE WHITNEY CONSTRUCTION CAMP AT THE DIVERSION DAM, FACING ...

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

    21. THE WHITNEY CONSTRUCTION CAMP AT THE DIVERSION DAM, FACING SOUTH. WOOD BURNING PLANT AT RIGHT, INTAKE GATES AT CENTER LEFT. Photographer: Walter J. Lubken, June 13, 1906 - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  1. 4. Aerial view of Whitsett intake (lower right), Parker Dam ...

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

    4. Aerial view of Whitsett intake (lower right), Parker Dam and village (left), Gene Wash Reservoir, Gene Pump Plant and village (right). - Parker Dam, Spanning Colorado River between AZ & CA, Parker, La Paz County, AZ

  2. Observing the Moon's Sodium Tail

    NASA Astrophysics Data System (ADS)

    Matta, Majd; Smith, Steven; Martinis, Carlos R.; Wilson, Jody; Baumgardner, Jeffrey; Mendillo, Michael

    Observations of the sodium (Na) tail of the Moon were made near times of new Moon between April and November 2006. Filtered images (Na D1+D2) were made from the El Leoncito Observatory in Argentina using the Boston University All-Sky Imager (ASI). Four of the eight new Moon periods had clear skies, and images from those nights were calibrated to absolute brightness levels in Rayleighs (R) using standard stars. Results reveal variability in the brightness of the Moon's sodium tail that may be linked to enhanced contributions from meteor showers.

  3. Spatio-temporal evaluation of Yamchi Dam basin water quality using Canadian water quality index.

    PubMed

    Farzadkia, Mahdi; Djahed, Babak; Shahsavani, Esmaeel; Poureshg, Yousef

    2015-04-01

    In recent years, the growth of population and increase of the industries around the tributaries of Yamchi Dam basin have led to deterioration of dam water quality. This study aimed to evaluate the quality of the Yamchi Dam basin water, which is used for drinking and irrigation consumptions using Canadian Water Quality Index (CWQI) model, and to determine the main water pollution sources of this basin. Initially, nine sampling stations were selected in the sensitive locations of the mentioned basin's tributaries, and 12 physico-chemical parameters and 2 biological parameters were measured. The CWQI for drinking consumptions was under 40 at all the stations indicating a poor water quality for drinking consumptions. On the other hand, the CWQI was 62-100 for irrigation at different stations; thus, the water had an excellent to fair quality for irrigation consumptions. Almost in all the stations, the quality of irrigation and drinking water in cold season was better. Besides, for drinking use, total coliform and fecal coliform had the highest frequency of failure, and total coliform had the maximum deviation from the specified objective. For irrigation use, total suspended solids had the highest frequency of failure and deviation from the objective in most of the stations. The pisciculture center, aquaculture center, and the Nir City wastewater discharge were determined as the main pollution sources of the Yamchi Dam basin. Therefore, to improve the water quality in this important surface water resource, urban and industrial wastewater treatment prior to disposal and more stringent environmental legislations are recommended. PMID:25750066

  4. "No. 172. General view of the dam, looking downstream from ...

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

    "No. 172. General view of the dam, looking downstream from the east end. F.E.D. June, 1916." Compare this historic image, taken upon dam completion (1916), with current-condition photograph HAER CO-90-1. The dam retains a remarkable degree of integrity of design and setting - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

  5. 2. View of the southern twothirds of the dam showing ...

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

    2. View of the southern two-thirds of the dam showing the Glens Falls Bridge over the Hudson River on the left, the Niagara Mohawk Power Corporation penstocks and inktake structure at the southeast corner of the dam, and the dam itself. The Finch Pruyn & Company Forebay is the foreground. Facing south. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  6. Evaluation of Reinforcement and Analysis of Stability of a High-Arch Dam Based on Geomechanical Model Testing

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Liu, Y. R.; Yang, Q.

    2015-03-01

    Reinforcement measures are often used in high-arch dams with complicated geological foundations. The geomechanical model test is an effective method to study the global stability of arch dams and to evaluate the reinforcement effects of foundation treatments. The block masonry technique was developed to simulate the jointed rock mass, tectonic discontinuities, and reinforcement measures. A tailor-made low-strength binder and small blocks were developed to simulate the strength and deformation of the jointed rock mass and discontinuities, respectively. We applied this technique to geomechanical model tests of the Dagangshan arch dam with and without foundation reinforcements. A rupture test was conducted, and the stress and displacement distribution of the dam and abutments were recorded; the failure mechanisms and processes were explored. The reinforcement effects of the foundation treatment were evaluated by comparing the test results of the models with and without foundation reinforcements. Our analysis indicates that foundation reinforcements can improve the stress distribution, decrease deformation, prevent slides, reduce fault movement, and improve the global stability of high-arch dams.

  7. 33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... false Marine Events on the Colorado River, between Davis Dam (Bullhead City...1102 Marine Events on the Colorado River, between Davis Dam (Bullhead City...Lake Moovalya, Parker, Arizona between river miles 179 and 185 (between the...

  8. 33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... false Marine Events on the Colorado River, between Davis Dam (Bullhead City...1102 Marine Events on the Colorado River, between Davis Dam (Bullhead City...Lake Moovalya, Parker, Arizona between river miles 179 and 185 (between the...

  9. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  10. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  11. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  12. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  13. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  14. 1. East apron upper dam with water flowing over overspill. ...

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

    1. East apron upper dam with water flowing over overspill. Photograph taken from crest of lower dam in foreground). VIEW WEST - Loleta Recreation Area, Upper Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  15. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  16. INCORPORATING UNCERTAINTY INTO DAM SAFETY RISK Sanjay S. Chauhan1

    E-print Network

    Bowles, David S.

    INCORPORATING UNCERTAINTY INTO DAM SAFETY RISK ASSESSMENT Sanjay S. Chauhan1 and David S. Bowles2 ABSTRACT Risk assessment is becoming more widely used to supplement traditional approaches to dam safety decision-making. Dam owners throughout Australia, the U.S. Army Corps of Engineers, and the U.S. Bureau

  17. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  18. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16... area, Coolidge Dam. No permit for any commercial business or other activity (except boating concessions...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  19. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Reserved area, Coolidge Dam. 173.16 Section 173.16 Indians..., Coolidge Dam. No permit for any commercial business or other activity (except boating concessions confined...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  20. THREE GORGES DAM Matthew Morioka, Alireza Abrishamkar, Yve Kay

    E-print Network

    Prevedouros, Panos D.

    THREE GORGES DAM Matthew Morioka, Alireza Abrishamkar, Yve Kay CEE 491 #12;Specifications.3 Billion · Total Cost (2008) ¥ 148.4 Billion = $ 21.8 Billion #12;Source of Funds · Three Gorges Dam Construction Fund · Profits from the Gezhouba Dam · Policy Loans from the Chinese Development Bank · Loans from

  1. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  2. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  3. 9. Analysis a. Analysis tools for dam removal

    E-print Network

    Tullos, Desiree

    9. Analysis a. Analysis tools for dam removal v. Hydrodynamic, sediment transport and physical are frequently the main concerns associated with a dam removal due to the possible effects on infrastructure reservoir sediment when removing a dam are river erosion, mechanical removal, and stabilization (ASCE 1997

  4. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16... area, Coolidge Dam. No permit for any commercial business or other activity (except boating concessions...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  5. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16... area, Coolidge Dam. No permit for any commercial business or other activity (except boating concessions...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  6. September 17, 2012 Dam Safety' 12, ASDSO| Denver, CO

    E-print Network

    Bowles, David S.

    September 17, 2012 Dam Safety' 12, ASDSO| Denver, CO Anurag Srivastava, David S. Bowles and Sanjay trees are a valuable way to model dam safety risks: · Loading (e.g. flood, earthquake) · System response in commercially-available event tree software applied to dam safety risk assessment · Discrete business risk

  7. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16... area, Coolidge Dam. No permit for any commercial business or other activity (except boating concessions...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  8. REVIEW PLAN John Redmond Dam Reservoir, Coffee County, Kansas

    E-print Network

    US Army Corps of Engineers

    #12;#12;REVIEW PLAN John Redmond Dam Reservoir, Coffee County, Kansas Reallocation Study Tulsa PLAN John Redmond Dam Reservoir, Coffee County, Kansas Reallocation Study Tulsa District TABLE review for the Final Reallocation Report to the John Redmond Dam and Reservoir, Coffee County, Kansas

  9. 55. AVALON DAM (Photographic copy of photo in Reservoirs ...

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

    55. AVALON DAM - (Photographic copy of photo in Reservoirs for Irrigation, Water-Power, and Domestic Water Supply. New York: John Wiley & Sons, 1902.) 'CANAL HEADGATES, LAKE AVALON DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  10. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Truckee River flows below Derby Dam by more than 20 percent in a...measured by the gauge below Derby Dam, is less than or equal to 100...the Truckee River below Derby Dam in order to meet annual flow...established by the United States Fish and Wildlife Service for...

  11. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Truckee River flows below Derby Dam by more than 20 percent in a...measured by the gauge below Derby Dam, is less than or equal to 100...the Truckee River below Derby Dam in order to meet annual flow...established by the United States Fish and Wildlife Service for...

  12. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Truckee River flows below Derby Dam by more than 20 percent in a...measured by the gauge below Derby Dam, is less than or equal to 100...the Truckee River below Derby Dam in order to meet annual flow...established by the United States Fish and Wildlife Service for...

  13. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Truckee River flows below Derby Dam by more than 20 percent in a...measured by the gauge below Derby Dam, is less than or equal to 100...the Truckee River below Derby Dam in order to meet annual flow...established by the United States Fish and Wildlife Service for...

  14. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Truckee River flows below Derby Dam by more than 20 percent in a...measured by the gauge below Derby Dam, is less than or equal to 100...the Truckee River below Derby Dam in order to meet annual flow...established by the United States Fish and Wildlife Service for...

  15. Dams and Water Developments1 Robert H. Schueneman

    E-print Network

    with dams such as outlet works, power generating facilities and fish ladders to facilitate migration. FishDams and Water Developments1 Robert H. Schueneman 2/ 1/ Presented at the National Conference dams and reservoirs, channelization and erosion control on rivers and tributaries, and coastal works

  16. 29. At Willard, Little Salmon Creek. Site of former dam ...

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

    29. At Willard, Little Salmon Creek. Site of former dam and water supply pond for Broughton flume. View from downstream of intake, dam wind wall to right, lower wall of overflow chute in left foreground (contains pipes and small dam, possibly for water pumping). West 320 degrees. - Broughton Flume, Hood River Junction on Columbia River at Washington/Oregon border, Hood, Skamania County, WA

  17. PVC waterproofing membranes and alkali-aggregated reaction in dams

    SciTech Connect

    Scuero, A.M.

    1995-12-31

    A waterproofing polyvinylchloride (PVC) based geocomposite was installed on two dams subject to alkali-aggregate reaction, to eliminate water intrusion and to protect the facing from further deterioration. The installation system allows drainage of the infiltrated water, thus accomplishing dehydration of the dam body. On one dam, the membrane also provided protection for future slot cutting.

  18. 6. VIEW OF NORTH END OF EAST DAM, LOOKING SOUTH. ...

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

    6. VIEW OF NORTH END OF EAST DAM, LOOKING SOUTH. (View is taken from lakeside with lowered water level. This view encompasses the same area as MT-88-A-5 above.) - Three Bears Lake & Dams, East Dam, North of Marias Pass, East Glacier Park, Glacier County, MT

  19. LOCK, DOG HOUSE, CONTROL STATION, DAM GATE, MANEUVER BOAT No. ...

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

    LOCK, DOG HOUSE, CONTROL STATION, DAM GATE, MANEUVER BOAT No. 1, AND DAM. NOTE LOWER LOCK GATE IN FOREGROUND. LOOKING NORTH NORTHEAST. - Illinois Waterway, La Grange Lock and Dam, 3/4 mile south of Country 795N at Illinois River, Versailles, Brown County, IL

  20. 7. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, WITH ...

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

    7. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, WITH OUTLET CULVERT AND WING RETAINING WALLS, LOOKING NORTH - High Mountain Dams in Upalco Unit, Twin Pots Dam, Ashley National Forest, 10.1 miles North of Mountain Home, Mountain Home, Duchesne County, UT

  1. 6. VIEW OF DAM 83, SHOWING OUTLET CHANNEL FLOWING INTO ...

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

    6. VIEW OF DAM 83, SHOWING OUTLET CHANNEL FLOWING INTO POND A WITH DIVERSION GATES LONG EAST (LEFT) SIDE OF OUTLET CHANNEL, LOOKING SOUTH FROM DOWNSTREAM FACE OF THE DAM - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

  2. 2. UPSTREAM SIDE OF DAM AND BRIDGE WITH ABANDONED SAN ...

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

    2. UPSTREAM SIDE OF DAM AND BRIDGE WITH ABANDONED SAN TAN FLOOD-WATER HEADGATE IN FOREGROUND. TAKEN FROM NORTH END OF DAM - San Carlos Irrigation Project, Sacaton Dam & Bridge, Gila River, T4S R6E S12/13, Coolidge, Pinal County, AZ

  3. 6. VIEW SHOWING CREST OF DAM AND OUTLET GATE WHEEL, ...

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

    6. VIEW SHOWING CREST OF DAM AND OUTLET GATE WHEEL, STEM AND STEM GUIDE, LOOKING SOUTHEAST - High Mountain Dams in Upalco Unit, Milk Lake Dam, Ashley National Forest, 9.4 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

  4. 28. Photocopied August 1978. UPPER INTAKE COFFER DAM, OCTOBER 7, ...

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

    28. Photocopied August 1978. UPPER INTAKE COFFER DAM, OCTOBER 7, 1901. LOGS WERE PLACED ON THE WATER SIDE OF THIS DAM TO COUNTERACT WAVE ACTION AGAINST THE DAM. NOTE THE TIMBER RETAINING WALL ON THE NORTH SIDE OF THE LOWER INTAKE. (185) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  5. SEISMIC RESPONSE OF DAM WITH SOIL-STRUCTURE INTERACTION.

    USGS Publications Warehouse

    Bycroft, G.N.; Mork, P.N.

    1987-01-01

    An analytical solution to the response of a long trapezoidal-section dam on a foundation consisting of an elastic half-space and subjected to simulated earthquake motion is developed. An optimum seismic design is achieved when the cross section of the dam is triangular. The effect of soil structure interaction is to lower the strain occurring in the dam.

  6. 20. VIEW FROM DOWNSTREAM SIDE OF DAM SHOWING BUTTS OF ...

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

    20. VIEW FROM DOWNSTREAM SIDE OF DAM SHOWING BUTTS OF LOGS PROJECTING BETWEEN CROSS LOGS. FREQUENTLY WHOLE TREES WERE USED IN CONSTRUCTING THESE DAMS. THE BRANCHES WERE PLACED UPSTREAM AND COVERED WITH EARTH AND STONE TO ANCHOR THEM. Photographed November 6, 1935. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

  7. 26Observing Dam's Movements with Spaceborne SAR Interferometry

    E-print Network

    Perissin, Daniele

    Gorges Dam (02­08/2011) Since 1994, the mass of water in the 660 km long reservoir behind Three Gorges due to significantly increased amount of water, areas around dams are affected by hydro26Observing Dam's Movements with Spaceborne SAR Interferometry Milan Lazecký, Daniele Perissin

  8. 1. VIEW OF DOWNSTREAM SIDE OF DIVERSION DAM ON THE ...

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

    1. VIEW OF DOWNSTREAM SIDE OF DIVERSION DAM ON THE SNAKE RIVER, LOOKING NORTHEAST. NOTE HEADGATE STRUCTURE ON NORTH BANK, SPILLWAY ON LEFT SIDE OF DAM, AND SPLASH LOGS ON DOWNSTREAM SIDE OF DAM. - Snake River Ditch, Headgate on north bank of Snake River, Dillon, Summit County, CO

  9. 30. Otter Lake Dam. View shows rustic stone facade of ...

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

    30. Otter Lake Dam. View shows rustic stone facade of the dam. The stepped face of the dam gives the illusion of a natural cascade. Facing southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  10. Facilitating fish passage at ultra low head dams: An alternative to dam removal

    USGS Publications Warehouse

    Odeh, M.

    2004-01-01

    Ecosystem sustainability and returning the biological integrity to rivers continue to change the landscape of fish passage technology. Installing a conventional fishways has a limited degree of success in accommodating fish passage needs. Recently, the option of total dam removal has been gaining momentum among resource managers, conservationists, and even engineers. Certain dams, however, cannot be removed, and conventional fishways are either too expensive to build or the real estate is simply not available; yet freedom of passage must be attained. At the Little Falls Dam on the Potomac River a notch in the crest of the dam was installed to accommodate passage of fish. The notch has three labyrinth weirs used for energy dissipation. Water velocities are maintained at less than about 4 m/s anywhere within the passage structure during migratory season of the target species (American shad). Construction of this novel design was recently completed (March 2000) and future biological evaluations are ongoing. Copyright ASCE 2004.

  11. Black-Tailed Prairie Dog

    USGS Multimedia Gallery

    Black-tailed prairie dogs are quite susceptible to sylvatic plague, but a new plague vaccine put in their food shows significant promise in the laboratory. The prairie dogs transmit the disease to endangered black-footed ferrets, who eat the prairie dogs and are also quite susceptible to the disease...

  12. Instanton Calculus of Lifshitz Tails

    E-print Network

    Sho Yaida

    2012-04-30

    For noninteracting particles moving in a Gaussian random potential, there exists a disagreement in the literature on the asymptotic expression for the density of states in the tail of the band. We resolve this discrepancy. Further we illuminate the physical facet of instantons appearing in replica and supersymmetric derivations with another derivation employing a Lagrange multiplier field.

  13. Tidal tails around globular clusters

    E-print Network

    M. Montuori; R. Capuzzo-Dolcetta; P. Di Matteo; P. Miocchi

    2007-09-04

    We present the results of detailed N-body simulations of clusters moving in a realistic Milky Way (MW) potential. The strong interaction with the bulge and the disk of the Galaxy leads to the formation of tidal tails, emanating from opposite sides of the cluster. Their orientation and morphology may be interpreted easily in terms of a comoving frame of coordinates.

  14. Dams and Salmon: A Northwest Choice

    ERIC Educational Resources Information Center

    Tucker, Michael; Tromley, Cheryl L.

    2005-01-01

    This article describes an experiential exercise in which participants assume the roles of various stakeholder groups in the controversy surrounding possible dam removal to revive northwestern U. S. salmon populations. The role-play (a) increases environmental awareness in the context of the competing interests various stakeholders have in our…

  15. Will We. . .? Thai Dam Resource Book.

    ERIC Educational Resources Information Center

    Murphy, Richard, Ed.; And Others

    This resource book is intended as an aid to persons working with Thai Dam refugees. To help the language teacher, some differences between Lao and English are discussed, specifically tonal inflections, positioning, declension of pronouns, conjugation of verbs, interrogatives, classifiers and predicate adjectives. An outline of cultural differences…

  16. Ethanol Consumption by Rat Dams During Gestation,

    E-print Network

    Galef Jr., Bennett G.

    , & Carmichael Olson, 1999). However, effects of maternally mediated prenatal and postnatal exposure to alcohol effects of drinking while pregnant on subsequent alcohol use by children of drinking mothers. Legal examined effects of ethanol consumption in rat dams during gestation, lactation, and weaning on voluntary

  17. Percy Quin Dam LiDAR Scan

    USGS Multimedia Gallery

    A 3-D terrestrial LiDAR scan of the Percy Quin Mississippi State Park Dam in McComb, Mississippi, taken Monday, September 3, 2012. The U.S. Geological Survey is using this new technology in select areas of Louisiana, Mississippi and Alabama to map impacts by Hurricane Isaac....

  18. fun in Amst--dam ichard Gill

    E-print Network

    Gill, Richard D.

    be an easy way to end up with nine scalable filled closed curvefun in Amst- -dam ichard Gill http://www.math.leidenuniv.nl/~gill September 2011 1: Reverse (but I could easily make it again) #12;#12;Postprocessing · Fill the 9 strips for final scalable image

  19. White Oak Dam stability analysis. Volume I

    SciTech Connect

    Ahmed, S.B.

    1994-01-01

    A parametric study was conducted to evaluate the stability of the White Oak Dam (WOD) embankment and foundation. Slope stability analyses were performed for the upper and lower bound soil properties at three sections of the dam using the PCSTABL4 computer program. Minimum safety factors were calculated for the applicable seismic and static loading conditions. Liquefaction potential of the dam embankment and foundation solid during the seismic event was assessed by using simplified procedures. The WOD is classified as a low hazard facility and the Evaluation Basis Earthquake (EBE) is defined as an earthquake with a magnitude of m{sub b} = 5.6 and a Peak Ground Accelerator (PGA) of 0.13 g. This event is approximately equivalent to a Modified Mercalli Intensity of VI-VIII. The EBE is used to perform the seismic evaluation for slope stability and liquefaction potential. Results of the stability analyses and the liquefaction assessment lead to the conclusion that the White Oak Dam is safe and stable for the static and the seismic events defined in this study. Ogden Environmental, at the request of MMES, has checked and verified the calculations for the critical loading conditions and performed a peer review of this report. Ogden has determined that the WOD is stable under the defined static and seismic loading conditions and the embankment materials are in general not susceptible to liquefaction.

  20. Dam water quality study. Report to Congress

    SciTech Connect

    Not Available

    1989-05-01

    The objective of the report is to identify water quality effects attributable to the impoundment of water by dams as required by Section 524 of the Water Quality Act of 1987. The document presents a study of water quality effects associated with impoundments in the U.S.A.

  1. Fish reproductive guilds downstream of dams.

    PubMed

    Vasconcelos, L P; Alves, D C; Gomes, L C

    2014-11-01

    Fish reproductive guilds were used to evaluate the responses of species with different reproductive strategies during two different periods of post-dam construction. The data used for the comparisons were collected in the upper Paraná River floodplain (Brazil), downstream of the Porto Primavera dam, 2 and 10 years after impoundment. The abundance (catch per unit effort, CPUE), species richness, evenness and structure of communities, all within reproductive guilds, were used to test the hypothesis that these metrics vary spatially and temporally. The influence of damming on species structure and the diversity of fish reproductive guilds varied spatiotemporally, and species with opportunistic reproductive strategies tended to be less affected. Conversely, long-distance migratory species responded more markedly to spatiotemporal variations, indicating that the ecosystem dynamics exert greater effects on populations of these species. Thus, the effects of a dam, even if attenuated, may extend over several years, especially downstream. This finding emphasizes the importance of maintaining large undammed tributaries downstream of reservoirs. PMID:25230203

  2. Radar proves its worth in dam rehabilitation

    SciTech Connect

    1996-08-01

    This article outlines the use of radar techniques to survey the masonry structure of White Marble Dam. The survey used a subsurface interface radar, and this equipment displayed a cross-sectional profile of the entire structure, revealing the size and location of any faults. By avoiding the draining and dredging of the upstream pool, it is estimated that this technique saved three months.

  3. Tail use in bioinspired quadrupedal locomotion

    E-print Network

    Briggs, Randall (Randall Miller)

    2012-01-01

    Tails are seen in nature to be used in an amazing number of different applications. Many of these applications seen in nature may be of use to bioinspired roboticists in the future. I have provided a brief review of tail ...

  4. From metallurgical coal tailings to thermal fuel

    SciTech Connect

    van den Broek, J.J.M.

    1982-01-01

    McIntyre Mines in Canada recover coal from washery tailings slurry. The tailings are dewatered in Bird screen bowl centrifuges and thermally dried in Joy Holo-Flite dryers. The coal recovered is burned in a power station.

  5. Lobster Tail Ice Formation on Aerosurface

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Glace Ice formation commonly refered to as 'Lobster Tail' by scientists and engineers, is caused to form on the leading edge of a aircraft tail section in the icing research tunnel at the NASA Glenn Research Center, Cleveland, Ohio.

  6. Modeling Finite-Time Failure Probabilities in Risk Analysis Applications.

    PubMed

    Dimitrova, Dimitrina S; Kaishev, Vladimir K; Zhao, Shouqi

    2015-10-01

    In this article, we introduce a framework for analyzing the risk of systems failure based on estimating the failure probability. The latter is defined as the probability that a certain risk process, characterizing the operations of a system, reaches a possibly time-dependent critical risk level within a finite-time interval. Under general assumptions, we define two dually connected models for the risk process and derive explicit expressions for the failure probability and also the joint probability of the time of the occurrence of failure and the excess of the risk process over the risk level. We illustrate how these probabilistic models and results can be successfully applied in several important areas of risk analysis, among which are systems reliability, inventory management, flood control via dam management, infectious disease spread, and financial insolvency. Numerical illustrations are also presented. PMID:26010201

  7. Clean Air Act Requirements: Uranium Mill Tailings

    E-print Network

    EPA'S Clean Air Act Requirements: Uranium Mill Tailings Radon Emissions Rulemaking Reid J. Rosnick requirements for operating uranium mill tailings (Subpart W) Status update on Subpart W activities Outreach/Communications #12;3 EPA Regulatory Requirements for Operating Uranium Mill Tailings (Clean Air Act) · 40 CFR 61

  8. Heavy Tails in Insurance Sren Asmussen

    E-print Network

    eqf21/008 Heavy Tails in Insurance Søren Asmussen Vicky Fasen and Claudia Klüppelberg Abstract. Keywords: compound Poisson process, Cramér-Lundberg model, integrated tail distribution, Pollaczek of heavy­tailed distribution functions, subexponential distribu- tion functions are a special class which

  9. Selective Tail Call Elimination Yasuhiko Minamide

    E-print Network

    Minamide, Yasuhiko

    Selective Tail Call Elimination Yasuhiko Minamide Institute of Information Sciences and Electronics University of Tsukuba and PRESTO, JST minamide@is.tsukuba.ac.jp Abstract. Tail calls are expected not to consume stack space in most functional languages. However, there is no support for tail calls in some

  10. Heavy Tails: Performance Models and Scheduling Disciplines

    E-print Network

    Núñez-Queija, Rudesindo

    Heavy Tails: Performance Models and Scheduling Disciplines Sindo N´u~nez-Queija based on joint ITC´u~nez-Queija CWI & TU/e #12;Heavy Tails: Performance Models and Scheduling Disciplines Part I ­ Introduction and Methodology Tales to tell: · traffic measurements and statistical analysis · traffic modeling · heavy-tailed

  11. Tales of the Tail: Hardware, OS, and Application-level Sources of Tail Latency

    E-print Network

    Anderson, Richard

    Tales of the Tail: Hardware, OS, and Application-level Sources of Tail Latency Jialin Li, Naveen Kr-scale parallel implemen- tations. To deliver fast responses, the median and tail laten- cies of a service tail latency in high throughput servers executing on multi-core machines. We model these network

  12. Gabcikovo dam and Liptovska Mara dam - statistical analysis of measurement data

    NASA Astrophysics Data System (ADS)

    Hakac, J.; Sabo, M.

    2012-04-01

    Introduction: Water level in the observation wells is measured regularly and one of the reasons is evaluation of the safety of the water constructions. In this paper we are exploring the reliability of the measuring devices that are responsible for evaluation of the safety of the two largest and the most important dams in Slovakia. We test ability of selected statistical methods to detect early inaccuracies of measuring devices and thus improve the evaluation of the safety of the water constructions. As a follow-up study, we used the time series model (Neural network) to predict water levels in the observation wells that were considered to be without defects. Neural Network is also able to show dynamics of the filtration stability of the observational well. Methods: On the Liptovska Mara dam weekly data was used as a monitoring tool. On the Gabcikovo dam five minute time series of the measurements of the water level in observation wells around the right lock chamber were used. Data from the measuring devices of the dams were explored with boxplots, correlations, neural network, etc. The mentioned statistical tools analyze time series and detect the errors that measuring devices make when generating data and can be used to predict errors even in real time. In the second step, agreement between predicted data from neural network and measured data in the real time was evaluated. We used grid search for finding the optimal number of neurons and then predicted errors by using this model. The ability of the neural network in evaluation of the sealing of the dilatation joints on the filtration stability in the years 2009 - 2011 is presented. Results: From the 18 selected measuring devices on the Liptovska Mara dam there are only 3 devices which can be considered as reliable. On the Gabcikovo dam, 8 of 9 measuring devices (observation wells around right lock chamber) were considered as a reliable. There was very good agreement between the predicted and measured data at the Liptovska Mara dam using the neural network model. At the Gabcikovo dam the dynamics of the filtration stability around the right lock chamber is presented. Conclusions: The significance of the neural network is the ability to predict the water level in the observation wells at a dam site and total filtration stability of the dams by using the real measures in the time series. This is a desirable step to ensure adequate safety with the possibility to solve potential defects earlier.

  13. The Non-finished, Non-well Compacted Soil of the Crest of Zayzoun Dam, the Technical and Administrative Errors, and the Correct Ways of its Reinforcement and Renovation

    NASA Astrophysics Data System (ADS)

    Hamze, Youssef; Stanivska, Anna

    Zayzoun dam is one of the irrigation elements of the valley of (Alkhab) in northern Syria; its exploitation started in 1996 and breached on June 4th, 2002. There were many experts searching for the causes of its failure and the correct ways of its renovation. There were many reports written about the failure with different opinions, and we have been one of these experts with an objective opinion. The principal aim was to study all the technical and administrative components of the dam, and to analyze the existing and the new laboratory testing. The soil of the unfinished summit of the dam, in the end, was found to be the real cause that led to its failure. These causes will be analyzed in order to avoid them in the future and to find the suitable ways of its renovation and reinforcement.

  14. The 2000 Yigong landslide (Tibetan Plateau), rockslide-dammed lake and outburst flood: Review, remote sensing analysis, and process modelling

    NASA Astrophysics Data System (ADS)

    Delaney, Keith B.; Evans, Stephen G.

    2015-10-01

    In April 2000 a large-scale rock avalanche dammed the Yigong Zangpo River, forming an extensive rockslide-dammed lake. The impoundment lasted for 62 days before a catastrophic breaching caused a massive outburst flood in the Yarlung Zangpo (Tibet) and the Dihang rivers (India) that travelled downstream to the main floodplain of the Brahmaputra in northeastern India. In response to discrepancies in the published literature on the event, we present a review and re-evaluation of the characteristics of the rock avalanche and associated landslide-dammed lake. We use digital topographical data (SRTM-3) and dynamic landslide modelling (DAN-W and DAN3D) to determine the salient characteristics of the damming landslide and to characterise its behaviour. Our analysis indicates that the volume of the damming rockslide was ca. 115 Mm3, including 91 Mm3 from the initial rockslope failure (bulked during disaggregation to 109 Mm3) and 6 Mm3 from entrainment during its 10.1 km travel down Zhamulong gully. The debris travelled with an average velocity of 15-18 m/s and resulted in a landslide dam on the Yigong River with a minimum height of about 55 m. Using LANDSAT-7 imagery (obtained before, during, and after impoundment) in conjunction with an SRTM-3 DEM, we reproduced the filling of the lake. We determine that the landslide dam formed an extensive reservoir with an impounded volume of 2.015 Gm3 and a maximum possible lake level of 2264 m asl (rounded to 2265 m asl). Our figures differ from those previously published but are believed to be well-constrained verifiable estimates of the volumes of the 2000 Yigong events. The outburst occurred after an attempt by army personnel to manually dig a spillway over the landslide debris and resulted in the entire volume of the lake draining in about 12 h. The outburst flood travelled over 500 km south into India, with a recorded rise in river level of 5.5 m at the Pasighat gauging station, 462 km downstream. In terms of historical outburst volumes from rockslide-dammed lakes, the volume of the 2000 Yigong event is only exceeded by that of the 1841 outburst flood from the Indus River rockslide-dammed lake, northern Pakistan.

  15. What Makes a Tidal Tail?

    NASA Astrophysics Data System (ADS)

    Rodruck, Michael; Konstantopoulos, I.; Charlton, J. C.

    2014-01-01

    Galaxy interactions are famous for creating some of the most visually stunning scenes in astronomy, particularly in the cases of tidal tails. These chaotic regions are known to house breeding grounds for young stellar clusters, as shown through past imaging and spectroscopic studies, but the underlying material remains a mystery. While we know that gas is easily stripped from the parent galaxies, what about the stars? The presence of an older stellar population is crucial to dynamical simulations of tidal tails, but has not yet been confirmed by observation. We use the twin tidal tails of NGC3256 as a case study for determining the presence of an old, underlying stellar population. Newly acquired ugriz Gemini data allows us to distinguish between young and old stars, while previous HST data pinpoints the locations of these objects. Deep imaging surveys have often been used to detect tidal features, including these ancient relics, but our survey will be the first to measure the colors of such objects. This will lead us to place constraints on the original composition of the material that was ejected from the interacting/merging galaxies, and the star formation history.

  16. Kinetochores require oligomerization of Dam1 complex to maintain microtubule attachments against tension and promote biorientation

    PubMed Central

    Umbreit, Neil T.; Miller, Matthew P.; Tien, Jerry F.; Cattin-Ortolá, Jérôme; Gui, Long; Lee, Kelly K.; Biggins, Sue; Asbury, Charles L.; Davis, Trisha N.

    2014-01-01

    Kinetochores assemble on centromeric DNA and present arrays of proteins that attach directly to the dynamic ends of microtubules. Kinetochore proteins coordinate at the microtubule interface through oligomerization, but how oligomerization contributes to kinetochore function has remained unclear. Here, using a combination of biophysical assays and live-cell imaging, we find that oligomerization of the Dam1 kinetochore complex is required for its ability to form microtubule attachments that are robust against tension in vitro and in vivo. An oligomerization-deficient Dam1 complex that retains wild-type microtubule binding activity is primarily defective in coupling to disassembling microtubule ends under mechanical loads applied by a laser trap in vitro. In cells, the oligomerization-deficient Dam1 complex is unable to support stable bipolar alignment of sister chromatids, indicating failure of kinetochore-microtubule attachments under tension. We propose that oligomerization is an essential and conserved feature of kinetochore components that is required for accurate chromosome segregation during mitosis. PMID:25236177

  17. Kinetochores require oligomerization of Dam1 complex to maintain microtubule attachments against tension and promote biorientation.

    PubMed

    Umbreit, Neil T; Miller, Matthew P; Tien, Jerry F; Ortolá, Jérôme Cattin; Gui, Long; Lee, Kelly K; Biggins, Sue; Asbury, Charles L; Davis, Trisha N

    2014-01-01

    Kinetochores assemble on centromeric DNA and present arrays of proteins that attach directly to the dynamic ends of microtubules. Kinetochore proteins coordinate at the microtubule interface through oligomerization, but how oligomerization contributes to kinetochore function has remained unclear. Here, using a combination of biophysical assays and live-cell imaging, we find that oligomerization of the Dam1 complex is required for its ability to form microtubule attachments that are robust against tension in vitro and in vivo. An oligomerization-deficient Dam1 complex that retains wild-type microtubule binding activity is primarily defective in coupling to disassembling microtubule ends under mechanical loads applied by a laser trap in vitro. In cells, the oligomerization-deficient Dam1 complex is unable to support stable bipolar alignment of sister chromatids, indicating failure of kinetochore-microtubule attachments under tension. We propose that oligomerization is an essential and conserved feature of kinetochore components that is required for accurate chromosome segregation during mitosis. PMID:25236177

  18. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the... Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the U. S... 7 Agriculture 11 2011-01-01 2011-01-01 false Dam safety. 1724.55 Section 1724.55...

  19. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the... Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the U. S... 7 Agriculture 11 2014-01-01 2014-01-01 false Dam safety. 1724.55 Section 1724.55...

  20. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the... Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the U. S... 7 Agriculture 11 2013-01-01 2013-01-01 false Dam safety. 1724.55 Section 1724.55...

  1. 7 CFR 1724.55 - Dam safety.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the... Office of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the U. S... 7 Agriculture 11 2012-01-01 2012-01-01 false Dam safety. 1724.55 Section 1724.55...

  2. Nile River, Lake Nasser, Aswan Dam, Egypt

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Egypt's High Aswan Dam on the Nile River at the first cataracts, Nile River, (24.0N, 33.0E) was completed in 1971 to provide cheap hydroelectric power and to regulate the historically uneven flow of the Nile River. The contrast between the largely base rock desert east of the Nile versus the sand covered desert west of the river and the ancient irrigated floodplain downstream from the damsite is clearly shown.

  3. Aswan Dam, Lake Nassar, Nile River, Egypt

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The Aswan Dam on the Nile River created the 500 kilometer long reservoir, seen here in sunglint. Lake Nassar (23.5N, 33.0E) was designed to control the devestating floods and alleviate the famine-producing droughts which have plagued the region for millenia. In Nov 81, as the lake was nearing capacity, drought conditions lowered the water level by about 30 meters which can clearly be seen as silt depositions on the receding eastern shoreline.

  4. A descriptive and quantitative approach regarding erosion and development of landforms on abandoned mine tailings: New insights and environmental implications from SE Spain

    NASA Astrophysics Data System (ADS)

    Martín Duque, J. F.; Zapico, I.; Oyarzun, R.; López García, J. A.; Cubas, P.

    2015-06-01

    The San Cristóbal-Perules mining site in Mazarrón in southeast Spain was subjected to about a hundred years of intense mining activity for lead, silver, and zinc. Metallurgical operations (smelting, calcination, gravity concentration) carried out during the late nineteenth century-early twentieth century induced significant land transformation, and the most conspicuous wastes of this period consist of a chaotic piling of 'old' tailing deposits. Later on, during the mid-twentieth century, 'modern' tailings resulting from froth flotation were accumulated filling small valleys; these latter valley-fill tailings rose sequentially according to the upstream construction method, progressively raising the level of the dam during the process. Once abandoned, both types of tailing deposits underwent severe erosion, resulting in a mosaic of erosional and sedimentary landforms developed upon (e.g., gully formation) and within them (e.g., piping). We made an inventory and classification of these landforms. Our study shows the geomorphic work to reestablish a new steady state between the tailings deposits and the local erosive conditions. This scenario implies several hazards related to the extremely high heavy metal contents of these tailings and the geomorphic instability of the deposits. We also quantified the tailings tonnage and erosion that occurred at one of the tailings dams (El Roble). As shown by an oblique aerial photograph taken in 1968, this dam had a terraced topography, whereas in 2013 this morphology had evolved into a badland-type relief with deep parallel gullies. By recognizing and surveying specific, remnant points along the benches and outslopes of the older terraced topography, we were able to build up a first digital elevation model (DEM1) reflecting the initial topography. A second DEM, this time showing the present topography, allowed quantification of erosion via Material Loss = DEM1 - DEM2. This yields an erosion rate (1968-2009) of 151.8 Mg (MT) ha- 1 y- 1, which matches well typical values for erosion of mined areas, commonly above 100 Mg (MT) ha- 1 y- 1. Abandoned mine tailing deposits are extremely common in the semiarid scenarios of the SW USA, Australia, Chile, and Peru. Given the similarities of these scenarios with SE Spain, the example from Mazarrón may provide useful new insights regarding the erosion and geomorphic evolution of such tailing deposits. These matters should be addressed in key environmental actions such as mine closure plans and land reclamation projects. A solution may come via restoration of these deposits through landform design involving the building up of stable mature landscapes, which in turn can withstand erosion much more easily.

  5. Dam removal increases American eel abundance in distant headwater streams

    USGS Publications Warehouse

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.

    2012-01-01

    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (<300 mm TL). We hypothesize that restoring connectivity to headwater streams could increase eel population growth rates by increasing female eel numbers and fecundity. This study demonstrated that dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  6. The Tous Dam Disaster of 1982: Risk communication and the origins of integrated flood risk management in Spain

    NASA Astrophysics Data System (ADS)

    Serra-Llobet, A.; Tàbara, J.; Sauri, D.

    2012-12-01

    The failure of Tous dam on the Júcar River near Valencia in 1982 was one of the most important socio-natural disasters in 20th century Spain. The death toll of 25 would have been much greater had not a local dam manager anticipated the failure and alerted mayors of a failure, before it actually occurred. The Tous Dam failure occurred a week before the first democratic elections in Spain after the Franco dictatorship, it received extensive coverage in the media. As a result, this disaster triggered a paradigm change in the way disaster risks were perceived and managed at multiple levels of government in Spain. Many factors, often of a qualitative and organisational nature, affect (vertical and horizontal) communication in disaster risk reduction learning and planning at the community level. Through interviews with key actors and stakeholders, content analysis of scientific literature, review of historical and media accounts, and analysis of legislation and regulation, we documented changes that resulted from the Tous Dam failure: (1) A process of institutional development, which led to the growth, and increase in complexity of the organisations involved both in vertical and horizontal communication of disaster risk reduction. (2) Actions taken and experiences gained in dealing with disaster risk reduction in the Tous area were used as a benchmark to develop new strategies, as well as new mechanisms for communication and planning in other territories and other risk domains in Spain.We identify three main stages from 1980s to present in the evolution of disaster risk reduction planning in the area, which show a progressive shift towards a more integrated and preventative approach: (1) After the collapse of the Tous Dam, disaster risk reduction strategies in Spain focused on improving preparedness in order to reduce short-term risks. (2) Disaster management in the 1990s was strongly influenced by international initiatives (e.g. the UN International Decade for Natural Disaster Reduction), which emphasized the contextualization of risk and the importance in long-term disaster risk reduction measures such as land use planning. (3) The European Water Framework Directive (2000) and, more recently, the Flood Directive (2007) are exerting a strong influence on the development of a new Spanish flood policy that focuses on preventive measures and integrates, for the first time, ecological concerns and climate change adaptation in flood management strategies.

  7. Functional exercise of Kingsley Dam emergency action plan

    SciTech Connect

    Boyd, K.M.

    1995-12-31

    At the request of the Federal Energy Regulatory Commission (F.E.R.C.), the Central Nebraska Public Power and Irrigation District (Central) performed a Functional Test of the Kingsley Dam Emergency Action Plan (E.A.P.) on October 27, 1992. The purpose of the exercise was to evaluate the Emergency Action Plan under a stress-induced environment with time constraints that exercised skills which are required for emergency management. This exercise was unique as it took place simultaneously at three different sites: North Platte Holiday Inn, Lincoln County Civil Defense Headquarters and the Keith County Civil Defense Office. Fifty miles separated the two Civil Defense Headquarters. There was a mobile command post that allowed radio communications between the different Civil Defenses offices. During the exercise, both levels of the E.A.P. (hazardous situation developing and failure has occurred) were tested. Both Keith and Lincoln County Civil Defense offices were able to test their own preparedness plans and communications. Besides the successful tests of the plans, a cooperative spirit was strengthened among the agencies as well as an exchange of knowledge and resources.

  8. Modelling landslide-generated tsunami: from landslide propagation to downstream flood in dam context

    NASA Astrophysics Data System (ADS)

    Franz, Martin; Podladchikov, Yury; Humair, Florian; Matasci, Battista; Jaboyedoff, Michel

    2015-04-01

    Alpine regions have a high density of dammed lakes, either natural or anthropogenic. Those are frequently surrounded by steep slopes and thus, are potentially affected by mass wasting processes. The penetration of landsliding material in the water body may lead to impulse waves that could overtop the dam and, in the worst case scenario, breach or break the latter. The possible resulting outburst flood is a serious threat for populated places, commonly concentrated downstream in the valleys. In order to assess the risk resulting from the succession of all phenomenon, a numerical model able to handle all of them is required. Although specific models of flooding simulation or wave propagation are efficient, there is currently no fully achieved model capable to integrate all the above-mentioned processes at the same time. In order to address this, we propose a new model capable to handle these difficult combinations and which is suitable for risk assessment in dam contexts. Our model is based on both the shallow water equations and viscous flow equations. The first ones are stabilised by the Lax-Friedrichs scheme and compute the wave propagation and the downstream flow, i.e. the wet state. The viscous flow equations are used for the dry state and to propagate the landslide body. The transition from one state to the other is ruled by a threshold based on the Reynolds number. First, in order to test the capacity of our model to endure critical situations, we conducted numerical sandbox tests such as Riemann problems, dam break, and landslide tsunami-related ones in 2 dimensions. In a second time, the model is applied on a real case study: the Oeschinen Lake (Switzerland). This naturally dammed lake is specifically selected since it is potentially affected by all above-mentioned phenomenon, including landsliding, wave generation, wave propagation in the water body and on the shore as well as the downstream flooding. Results show that the municipality of Kandersteg, located 3 km downstream the dam, is subject to catastrophic consequences in case of slope failure of large rock compartments from the slopes above the lake.

  9. Asynchronous Failure Detectors

    E-print Network

    Cornejo, Alejandro

    2013-10-10

    Failure detectors -- oracles that provide information about process crashes -- are an important abstraction for crash tolerance in distributed systems. The generality of failure-detector theory, while providing great ...

  10. Characterization of grain sizes in the reservoir impoundment behind Marmot Dam post-dam removal

    NASA Astrophysics Data System (ADS)

    di Leonardo, D. R.; Podolak, C.; Wilcock, P.

    2009-12-01

    Marmot Dam was built in 1913 and stood until 2007 to divert water from the Sandy River to the Bull Run Hydroelectric Plant. During that time Marmot Dam impounded a reservoir deposit of approximately 750,000 cubic meters of sediment. Prior to dam removal Squier Associates completed a series of sediment cores and bulk samples to estimate the composition of the deposit (Stillwater 2000). Since 2007 the Sandy River has carved a path through the reservoir leaving vertical sections of the deposit exposed. This study aims to use these remains of the deposit to make another estimate of its composition using pebble counts and a bulk sample. It serves as a back of the envelope double check of the Squier Associates study and an experiment with a new sampling method. Our results suggest that the deposit may be coarser than previously thought

  11. The long-term environmental impacts of the Mount Polley mine tailings spill, British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Byrne, Patrick; Hudson-Edwards, Karen; Macklin, Mark; Brewer, Paul; Bird, Graham; Williams, Richard

    2015-04-01

    On the 4th August 2014 a tailings impoundment failure at the Mount Polley gold and copper mine in British Columbia, Canada, released approximately 25 million m3 of solid and liquid waste into Hazeltine Creek, Quesnel Lake and Polley Lake. The sheer volume of the tailings released caused Haseltine Creek channel to expand from 2m to over 25m in width and Polley Lake water level to rise by 1.7m. The spill also removed trees in a 900 km2 corridor either side of Hazeltine Creek. Local residents and government officials have expressed serious concerns regarding the potential long-term effects on regional biodiversity, water security and to the livelihoods of First Nation communities. Among impoundment failures, the Mount Polley disaster is unique in that the solid tailings contain an unusual mixture of metal contaminants (arsenic, copper, gold, manganese, nickel, lead, vanadium). As particulate matter is the principal carrier of metal contaminants, the spilled tailings may reside in the regional soils and sediments for 1000s of years serving as a secondary source of pollution. The environmental risk posed by the spilled tailings is compounded by the location of the spill in a mountainous forested catchment, affected by severe winters with prominent spring snow melts that have the potential to remobilise very large quantities of spilled tailings. No data currently exist on the short- to long-term behaviour of these tailings in soils and sediments and the effects of the clean-up operations on their behaviour in this type of river environment. In this study, we adopt a multidisciplinary approach to determine the environmental and geomorphological impacts of the tailings spill. We have two specific objectives. (1) The physicochemical speciation and geochemical stability of spilled tailings will be characterised in surface and hyporheic sediments using bulk chemistry, mineralogical (XRD and SEM) and speciation methods (sequential extractions, electron microprobe analysis, XAS). (2) Pre- and post-remediation geomorphological assessments will use unmanned aerial vehicle (UAV) photographic surveys and ground-based topographic surveys to (i) establish the efficacy of remediation efforts in stabilising Hazeltine Creek channel and (ii) quantify the physical remobilisation of tailings during the spring snowmelt.

  12. Modeling the costs and benefits of dam construction from a multidisciplinary perspective

    E-print Network

    Tullos, Desiree

    Modeling the costs and benefits of dam construction from a multidisciplinary perspective Philip H: Dam construction Dam removal Program evaluation a b s t r a c t Although the benefits of dam for electricity, recent experience has shown that many dams have serious negative environmental, human

  13. Providing protection: Agencies receive funding to repair, upgrade dams 

    E-print Network

    Wythe, Kathy

    2009-01-01

    by Kathy Wythe tx H2O | pg. 26 Providing protection Agencies receive funding to repair, upgrade dams along with local partners, can apply for grant funds, he said. Construction of the dams began through four federal authorizations passed between... 1944 and 1981. Land rights were acquired from landowners, and local agencies constructed the dams with federal money from NRCS (formerly the Soil Conservation Service). Local sponsors?including cities, counties, local soil and water conservation...

  14. Automated 3-D analysis of Gravity Dam stability

    SciTech Connect

    Barrett, P.R.; Boggs, H.

    1995-12-31

    The safety and stability of nonfederal hydroelectric project dams in the U.S. is a responsibility of the Federal Energy Regulatory Commission (FERC). FERC requires dam owners to reevaluate their structure`s stability every five years. In spite of the fact that FERC guidelines allow owners to use a variety of analytical approaches, millions of dollars are spent each year on safety modifications based on sometimes very conservative analysis methods. Analysis methods are often limited to hand calculations that assume a 2-D rigid body bending response of the dam or automated 2-D finite element analyses which can sometimes predict smaller safety factors than the rigid body analyses. Evaluation of dam stability using 3-D finite element analyses can sometimes reduce the conservatism in evaluating a dam`s stability even when conventional wisdom suggests that a 2-D analysis is sufficient. Significant increases in stability obtained from the 3-D analyses come primarily from the confining stresses from the dam abutments and the redistribution of load along the dam`s length. Even when the confining stresses are relatively small, large changes in sliding safety factors can be seen, since most dams, stability is extremely sensitive to variations in dam-rock interface cracks. The confining stresses reduce the propagation of cracks. The length of crack controls the magnitude of uplift loads applied to the bottom of the dam which in turn potentially leads to longer crack lengths. Both crack length and magnitude of uplift load directly effect the sliding stability factor of safety.

  15. 3D effects on the seismic performance of earthfill dams.

    NASA Astrophysics Data System (ADS)

    Berhe, Tensay; Wu, Wei

    2010-05-01

    Conventionally the seismic performance of earth dams is usually studied by assuming plane-strain problems. However, considerable effort is required to estimate the overall three dimensional dynamic response of dams as a result of earthquake hazard. The cumbersomeness increases when the dam is to be constructed in narrow canyon. This is so because the plane strain analysis does not take into account the arching effect of the valley which is particularly relevant for dams in narrow valleys. Researches reported in this paper represent 3D numerical study of an earthfill dam subjected to earthquake loading and 3D effects on its seismic performance. The shapes of the canyon are varied to determine the related 3D effects to the seismic performance of the assumed earthfill dam model. A finite difference numerical code, FLAC3D is used during the study. The assumed 3D model contains all details of the dam body and foundation materials of Tendaho earthfill dam. The dam is an earth fill dam located in Afar regional state of Ethiopia. The area is a seismically active area as it lies on the East African Rift valley which can generate earthquake of magnitude greater than 6. The results of the study indicated an important clue which analysis model (3D or 2D) to use for which problem. Results and discussions related with the 3D effects on the seismic performance of earthfill dams are presented and applied to the seismic performance study of Tendaho dam. Keywords: 3D, narrow canyon, seismic performance, earthquake hazard, plane-strain, arching.

  16. 1. CONTEXTUAL VIEW OF THE NORTH CHANNEL DAM FROM PUBLICLY ...

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

    1. CONTEXTUAL VIEW OF THE NORTH CHANNEL DAM FROM PUBLICLY RESTRICTED PROPERTY OF THE RECENTLY CLOSED LOUISIANA PACIFIC LUMBER MILL. THE NORTH CHANNEL DAM'S HOLDING RESERVOIR AND TAINTER GATES ARE IN THE FOREGROUND, AND THE ROLLING SECTOR GATE IS IN THE BACKGROUND, LOOKING EAST. - Washington Water Power Company Post Falls Power Plant, North Channel Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  17. Characterization of landslide dams in the San Juan province (Argentina)

    NASA Astrophysics Data System (ADS)

    Penna, Ivanna; Longchamp, Celine; Derron, Marc-Henri; Jaboyedoff, Michel

    2013-04-01

    River blockages caused by landslide deposition are common phenomena in active mountain chains, influencing erosion-sedimentation patterns and acting as primary and secondary hazards. Regional scale analyses regarding their spatial distribution and morphometry allow establishing boundary conditions for their occurrence and stability, and determine differences among regions with different landscape and climatic conditions. Owing to the combination of endogenous and exogenous factors, landslide dams are frequent phenomena in the Andes. In the Argentinean NW and the Patagonian Andes, previous studies showed that stability of landslide dams determined by morphometric parameters generally matched satisfactorily with dam behavior, with some exceptions in which climatic component played an important role in dam longevity. Aiming to expand the knowledge of landslide dams in the Argentinean Andes, in this work we analyzed the stability of rock avalanche dams in the Pampeam flat slab subduction zone. In the study area, mountain dynamics creates suitable conditions for the occurrence of 34 rock avalanches with volumes up to 0.3 km3. They developed in deeply carved valleys (Cordillera) and Inter-thrust valleys (Precordillera). 22 impoundments of rivers resulted from channelized rock avalanches with long runouts (4-10 km) that blocked tributaries rivers, but most of them by rock avalanches that filled the valley bottom, with run up in the opposite slope and limited movement parallel to the valley axis. Most of the dams breached in unknown times, except for the last event that occurred on November 12th 2005. The quantification of morphometric parameters and contributing areas indicates the existence of dams with dimensionless blockage index above 2.75 (stable domain) and below 3.08 (instable domain). The Los Erizos dam in our study area and the Barrancas dam in the Patagonian Andes show that besides morphometric parameters, climatic conditions are decisive. Stable landslide dams lasting for millennia can collapse suddenly due to anomalous weather conditions, and unstable dams can have a higher longevity depending on the season controlling the inflow into the lake.

  18. Oblique view, looking west, of top side of diversion dam, ...

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

    Oblique view, looking west, of top side of diversion dam, also showing eastern profiles of piers and gatehouses. Roller gate (raised position) on right. Note detail of extension shield that, when lowered to a secure position against the dam sill, creates a virtually impervious seal - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

  19. Antithrombotics in heart failure

    PubMed Central

    Mili?i?, Davor; Samardži?, Jure; Petri?evi?, Mate

    2014-01-01

    Heart failure is a common clinical condition associated with high morbidity and mortality rate despite significant improvements in pharmacotherapy and implementation of medical procedures. Patients with heart failure are at an increased risk of developing arterial and venous thrombosis, which contribute to the high rate of adverse events and fatal outcomes. Many heart failure patients routinely receive antithrombotic therapy due to the presence of a specific indication for its use, like ischemic heart disease or atrial fibrillation. However, there is no solid evidence to support the routine use of antithrombotic agents in all heart failure patients. This article reviews the evidence for using antithrombotic therapy in heart failure patients. PMID:25559833

  20. Class of dependent failures

    SciTech Connect

    Papazoglou, I.A.

    1981-01-01

    The purpose of this paper is to analyze the effect on the reliability of redundant systems of a class of dependent failures that are due to causes internal to the system (sympathetic failures). A general Markovian model that can incorporate both common cause (externally generated) and sympathetic failures is developed. The model includes the ..beta..-factor model and the Marshall-Olkin model as special cases. Three specialized versions of the general model are presented. It is shown that sympathetic failures can restrict the achievable reliability of a system beyond the limit set by common cause failures.