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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. 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.

  5. 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)

  6. 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

  7. 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.

  8. 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

  9. Erosion control on tailings dams using soil bioengineering

    SciTech Connect

    Miller, M.

    1996-12-31

    Increased awareness of the complexity of ecosystems has generated the need to integrate all facets of mining into the development of sustainable environmental management plans. Environmental management goals that may previously have concentrated on final closure of the mine are now becoming part of the preliminary planning and day-to-day activities of new mines, and are being integrated into planning goals of established operations. These management goals must address all components of a mining operation, including those relating to long-term maintenance of tailings areas. The long-term maintenance of tailings dams presents a challenge to the operations and reclamation divisions of minesites. Reducing, and eventually eliminating long-term maintenance and monitoring of surface slope stability on tailings dams has been identified as a cost-effective measure that can lead to the diversification of natural systems. An application of bioengineering techniques on a tailings dam at the INCO Limited Copper Cliff tailings complex is the focus of this poster. Soil bioengineering is a slope stabilization technique that uses dormant live plant material as the major engineering component. Unrooted live vegetation is installed on the slope, which provides immediate stabilization. Roots and shoots then develop to form a permanent vegetative cover and root reinforcing matrix. Bioengineered slopes strengthen over time as the root matrix develops, and provide a microclimate for the invasion of natural species, thus encouraging biodiversity and successional development. Live fascines were installed in the fall of 1994 on the face of the dam to slow the velocity of surface water runoff and to facilitate subsurface water movement in saturated conditions. The structures performed extremely well during their first growing season, and are currently being monitored to assess long-term performance.

  10. 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.

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

    USGS Publications Warehouse

    Torres-Sierra, Heriberto; Gůmez-Fragoso, Julieta

    2015-01-01

    Results from the simulated dam failure of the Lago de Matrullas Dam using the HECĖRAS 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 RŪo Grande de ManatŪ. Among the areas most affected are the low-lying regions in the vicinity of the towns of Ciales, ManatŪ, 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 RŪo Grande de ManatŪ 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 24-hour probable-maximum-precipitation dam failure scenarios. No overtopping of the levee was simulated, however, during dam failure scenarios under the 100-year recurrence, 24-hour rainfall event or sunny day conditions.

  12. 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‚ÄďRAS 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 R√≠o Grande de Manat√≠. Among the areas most affected are the low-lying regions in the vicinity of the towns of Ciales, Manat√≠, 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 R√≠o Grande de Manat√≠ 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 24-hour probable-maximum-precipitation dam failure scenarios. No overtopping of the levee was simulated, however, during dam failure scenarios under the 100-year recurrence, 24-hour rainfall event or sunny day conditions.

  13. Analysis of seismic disaster failure mechanism and dam-break simulation of high arch dam

    NASA Astrophysics Data System (ADS)

    Zhang, Jingkui; Zhang, Liaojun

    2014-06-01

    Based on a Chinese national high arch dam located in a meizoseismal region, a nonlinear numerical analysis model of the damage and failure process of a dam-foundation system is established by employing a 3-D deformable distinct element code (3DEC) and its re-development functions. The proposed analysis model considers the dam-foundation-reservoir coupling effect, influence of nonlinear contact in the opening and closing of the dam seam surface and abutment rock joints during strong earthquakes, and radiation damping of far field energy dissipation according to the actual workability state of an arch dam. A safety assessment method and safety evaluation criteria is developed to better understand the arch dam system disaster process from local damage to ultimate failure. The dynamic characteristics, disaster mechanism, limit bearing capacity and the entire failure process of a high arch dam under a strong earthquake are then analyzed. Further, the seismic safety of the arch dam is evaluated according to the proposed evaluation criteria and safety assessment method. As a result, some useful conclusions are obtained for some aspects of the disaster mechanism and failure process of an arch dam. The analysis method and conclusions may be useful in engineering practice.

  14. 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 slope stability numerical modelling. In the SSR finite element technique, elasto-plastic strength is assumed for dam's materials and shear strengths are progressively reduced until collapse occurs. Numerical modelling was performed on the most critical profile choosed through analysis of geophysical and geotechnical informational volume achieved by insitu or in laboratory tests. Finite element analysis were considered in two situations: first, before geophysical investigations and second considering the whole informational of data achieved. Both situations were analysed in static and pseudo-static conditions. The factor of safety before geophysical investigations is high enough to describe a stable state of stability even for the seismic load. The total displacement distributions were modified by the presence of internal erosional element giving a high state of instability, especially for the pseudo-static case. These analysis using the finite element method prove the importance of structural disturbance elements that may occure inside the dam body produced by internal erosional processes.

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

    NASA Astrophysics Data System (ADS)

    Van√≠ńćek, I.; Van√≠ńćek, M.; Jir√°sko, 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. International small dam safety assurance policy benchmarks to avoid dam failure flood disasters in developing countries

    NASA Astrophysics Data System (ADS)

    Pisaniello, John D.; Dam, Tuyet Thi; Tingey-Holyoak, Joanne L.

    2015-12-01

    In developing countries small dam failure disasters are common yet research on their dam safety management is lacking. This paper reviews available small dam safety assurance policy benchmarks from international literature, synthesises them for applicability in developing countries, and provides example application through a case study of Vietnam. Generic models from 'minimum' to 'best' practice (Pisaniello, 1997) are synthesised with the World Bank's 'essential' and 'desirable' elements (Bradlow et al., 2002) leading to novel policy analysis and design criteria for developing countries. The case study involved 22 on-site dam surveys finding micro level physical and management inadequacies that indicates macro dam safety management policy performs far below the minimum benchmark in Vietnam. Moving assurance policy towards 'best practice' is necessary to improve the safety of Vietnam's considerable number of hazardous dams to acceptable community standards, but firstly achieving 'minimum practice' per the developed guidance is essential. The policy analysis/design process provides an exemplar for other developing countries to follow for avoiding dam failure flood disasters.

  17. 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.

  18. The geomorphic influences of beaver dams and failures of beaver dams

    NASA Astrophysics Data System (ADS)

    Butler, David R.; Malanson, George P.

    2005-10-01

    Uncounted millions of beaver ponds and dams existed in North America prior to European contact and colonization. These ponds acted as sediment traps that contained tens to hundreds of billions of cubic meters of sediment that would otherwise have passed through the fluvial system. Removal of beavers by overtrapping in the 16th-19th centuries severely reduced their number and the number of ponds and dams. Dam removal altered the fluvial landscape of North America, inducing sediment evacuation and entrenchment in concert with widespread reduction in the wetlands environments. Partial recovery of beaver populations in the 20th century has allowed reoccupation of the entirety of the pre-contact range, but at densities of only one-tenth the numbers. Nevertheless, modern beaver ponds also trap large volumes of sediment in the high hundred millions to low billions of cubic meters range. Failure of beaver dams is a more common phenomenon than often assumed in the literature. During the past 20 years, numerous cases of dam failure have been documented that resulted in outburst floods. These floods have been responsible for 13 deaths and numerous injuries, including significant impacts on railway lines.

  19. Design, construction and management of tailings storage facilities for surface disposal in China: case studies of failures.

    PubMed

    Wei, Zuoan; Yin, Guangzhi; Wang, J G; Wan, Ling; Li, Guangzhi

    2013-01-01

    Rapid development of China's economy demands for more mineral resources. At the same time, a vast quantity of mine tailings, as the waste byproduct of mining and mineral processing, is being produced in huge proportions. Tailings impoundments play an important role in the practical surface disposal of these large quantities of mining waste. Historically, tailings were relatively small in quantity and had no commercial value, thus little attention was paid to their disposal. The tailings were preferably discharged near the mines and few tailings storage facilities were constructed in mainland China. This situation has significantly changed since 2000, because the Chinese economy is growing rapidly and Chinese regulations and legislation require that tailings disposal systems must be ready before the mining operation begins. Consequently, data up to 2008 shows that more than 12 000 tailings storage facilities have been built in China. This paper reviews the history of tailings disposal in China, discusses three cases of tailings dam failures and explores failure mechanisms, and the procedures commonly used in China for planning, design, construction and management of tailings impoundments. This paper also discusses the current situation, shortcomings and key weaknesses, as well as future development trends for tailings storage facilities in China. PMID:23064963

  20. 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.

  1. On the liquefaction failure of an earth dam

    SciTech Connect

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

    1993-12-01

    In an effort to better assess the potential for sliding and liquefaction failure of earthen dams when subjected to earthquake loadings, a dynamic finite element approach focusing on these two failure mechanisms as well as on the vital role of the pore water pressure was undertaken. The constitutive response of the granular soil skeleton and its coupling with the fluid phase is formulated based on the Blot dynamic equations of motion. The constitutive model for the soil material was assumed to be linear with nonlinear terms included in the hysteretic damping terms. Despite the linear character of this theoretical model, one can still draw important conclusions regarding the stability and the liquefaction resistance of the cross-section. As an example, a hypothetical earth dam constructed over a saturated soil layer was considered. The steady state conditions of in-situ stress and pore pressure distributions in both the embankment and the foundation are evaluated and implemented in the stability and liquefaction criteria in conjunction with the dynamic analysis. The latter is carried out in the frequency domain and it reflects the response of the dam-foundation system to a seismic excitation. The computational aspect of the study is performed with finite element analysis. A transmitting boundary formulation for the two phase material was used to treat the infinite space problem. It is anticipated that the intensity of the earthquake input and certain soil properties have a profound effect on the failure susceptibility of the dam section. To address the uncertainties regarding the true values of such parameters, the analysis considered them parametrically.

  2. 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.

  3. A New Method for System Reliability Analysis of Tailings Dam Stability

    NASA Astrophysics Data System (ADS)

    Liu, X.; Tang, H.; Xiong, C.; Ni, W.

    2012-12-01

    For the purpose of stability evaluation, a tailings dam can be considered as an artificial slope made of special soil materials which mainly come from mine tailings. As a particular engineering project, a tailings dam generally has experienced multi-loop hydraulic sediments as well as a long-term consolidation in the process of construction. The characteristics of sediment and consolidation result in a unique distribution of the soil layers with significant uncertainties, which come from both nature development and various human activities, and thus cause the discrete and the variability of the physical-mechanical properties dramatically greater than the natural geo-materials. Therefore, the location of critical slip surface (CSS) of the dam usually presents a notable drift. So, it means that the reliability evaluation task for a tailings dam is a system reliability problem indeed. Unfortunately, the previous research of reliability of tailings dam was mainly confined to the limit equilibrium method (LEM), which has three obvious drawbacks. First, it just focused on the variability along the slip surface rather than the whole space of the dam. Second, a fixed CSS, instead of variable one, was concerned in most cases. Third, the shape of the CSS was usually simplified to a circular. The present paper tried to construct a new reliability analysis model combined with several advanced techniques involving finite difference method (FDM), Monte Carlo simulation (MCS), support vector machine (SVM) and particle swarm optimization (PSO). The new framework was consisted of four modules. The first one is the limit equilibrium finite difference mode, which employed the FLAC3D code to generate stress fields and then used PSO algorithm to search the location of CSS and corresponding minimum factor of safety (FOS). The most value of this module was that each realization of stress field would lead to a particular CSS and its FOS. In other words, the consideration of the drift of CSS was significant to system reliability analysis. Besides, the CSS was described with non-circular shape, which was much more superior to the circular one. Moreover, compare with the LEM, the numerical method has the ability to reflect the variability in a whole space of the dam. The second one is the orthogonal design modules aimed to generate high-quality training samples according to the variability of soil layers. The third one is the response surface model based on SVM, which was designed to obtain the explicit performance function through the well-prepared training samples. The fourth one is the MCS model, which can perform steady and effective reliability analysis through the explicit performance function. As a result, a new approach for reliability analysis of tailings dam stability was presented. As a case study, the Yong-ping Copper Mine Tailings Dam in Jiangxi Province of China was analyzed in detail by this new method. It was shown that the effectiveness of the new method is considerable. In sum, this research is geared towards providing new ideas and available examples for future reliability assessment of tailings dam stability.

  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. ISSUES, RESOLUTIONS, AND RESEARCH NEEDS RELATED TO EMBANKMENT DAM FAILURE ANALYSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This document is the proceedings of a 3-day workshop on "Issues, Resolutions, and Research Needs Related to Embankment Dam Failure Analysis," held in Oklahoma City, OK, June 26-28th, 2001. The workshop consisted of convening and facilitating a group of experts with respect to dam safety associated ...

  6. Failure of a massive earthquake-induced landslide dam in Papua New Guinea

    USGS Publications Warehouse

    King, J. P.; Loveday, I. C.; Schuster, R.L.

    1987-01-01

    This article discusses the recent occurrence of a large earthquake-induced landslide that dammed the Bairaman River in the interior of hte island of New Britian, Papua New Guinea, and the subsequent overtopping and failure of this landslide dam. 

  7. Application of correspondence analysis in the assessment of mine tailings dam breakage risk in the Mediterranean region.

    PubMed

    Salgueiro, Ana Rita; Pereira, Henrique Garcia; Rico, Maria-Teresa; Benito, Gerado; Díez-Herreo, Andrés

    2008-02-01

    A new statistical approach for preliminary risk evaluation of breakage in tailings dam is presented and illustrated by a case study regarding the Mediterranean region. The objective of the proposed method is to establish an empirical scale of risk, from which guidelines for prioritizing the collection of further specific information can be derived. The method relies on a historical database containing, in essence, two sets of qualitative data: the first set concerns the variables that are observable before the disaster (e.g., type and size of the dam, its location, and state of activity), and the second refers to the consequences of the disaster (e.g., failure type, sludge characteristics, fatalities categorization, and downstream range of damage). Based on a modified form of correspondence analysis, where the second set of attributes are projected as "supplementary variables" onto the axes provided by the eigenvalue decomposition of the matrix referring to the first set, a "qualitative regression" is performed, relating the variables to be predicted (contained in the second set) with the "predictors" (the observable variables). On the grounds of the previously derived relationship, the risk of breakage in a new case can be evaluated, given observable variables. The method was applied in a case study regarding a set of 13 test sites where the ranking of risk obtained was validated by expert knowledge. Once validated, the procedure was included in the final output of the e-EcoRisk UE project (A Regional Enterprise Network Decision-Support System for Environmental Risk and Disaster Management of Large-Scale Industrial Spills), allowing for a dynamic historical database updating and providing a prompt rough risk evaluation for a new case. The aim of this section of the global project is to provide a quantified context where failure cases occurred in the past for supporting analogue reasoning in preventing similar situations. PMID:18304103

  8. 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...

  9. Methods 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.

    1997-01-01

    Floods from failures of natural and constructed dams constitute a widespread hazard to people and property. Expeditious means of assessing flood hazards are necessary, particularly in the case of natural dams, which may form suddenly and unexpectedly. We revise statistical relations (derived from data for past constructed and natural dam failures) between peak discharge (Q(p)) and water volume released (V(0)) or drop in lake level (d) but assert that such relations, even when cast into a dimensionless form, are of limited utility because they fail to portray the effect of breach-formation rate. We then analyze a simple, physically based model of dam-breach formation to show that the hydrograph at the breach depends primarily on a dimensionless parameter ?? = kV0/g1/2d7/2, where k is the mean erosion rate of the breach and g is acceleration due to gravity. The functional relationship between Q(p) and ?? takes asymptotically distinct forms depending on whether ?? > 1 (relatively fast breach formation or large lake volume). Theoretical predictions agree well with data from dam failures for which k, and thus ??, can be estimated. The theory thus provides a rapid means of predicting the plausible range of values of peak discharge at the breach in an earthen dam as long as the impounded water volume and the water depth at the dam face can be estimated.

  10. Use of stone wool by-products in the construction of sanitary landfills and tailing dams.

    PubMed

    Grosso, Battista; Muntoni, Aldo; Carucci, Alessandra; Cigagna, Marco; Virdis, Bernardino

    2004-01-01

    The delay of the introduction of a used item or residual material in the "waste circuit" is a key factor of an effective and environmentally sound waste management policy. This principle has been fully adopted by the European legislation and consequently, in most of the member countries. In the same time, re-use of low cost materials or, even better, by-products in environment protection works (sanitary landfills, mineral processing residues dams, etc.) could make easier the effective implementation of an environmentally sound waste management policy, especially in developing countries. However, the assessment of the recovery options has to be performed on the basis of proper technical specifications concerning the kind of reuse proposed and of an accurate investigation on the technical and environmental properties of the residue. The present article reports the results of a research programme aiming at evaluating the feasibility of use of stone wool by-products, usually directly disposed in landfills, as construction materials for sanitary landfills and tailing dams. PMID:15137703

  11. Scale amplification of natural debris flows caused by cascading landslide dam failures

    NASA Astrophysics Data System (ADS)

    Cui, P.; Zhou, Gordon G. D.; Zhu, X. H.; Zhang, J. Q.

    2013-01-01

    Debris flows are typically caused by natural terrain landslides triggered by intense rainfalls. If an incoming mountain torrent collapses a series of landslide dams, large debris flows can form in a very short period. Moreover, the torrent can amplify the scale of the debris flow in the flow direction. The catastrophic debris flows that occurred in Zhouqu, China, on 8 August 2010 were caused by intense rainfall and the upstream cascading failure of landslide dams along the gullies. In the wake of the incident, a field study was conducted to better understand the process of cascading landslide dam failures and the formation of debris flows. This paper looks at the geomorphic properties of the debris-flow gullies, estimates the peak flow discharges at different locations using three different methods, and analyzes the key modes (i.e., different landslide dam types and their combinations) of cascading landslide dam failures and their effect on the scale amplification of debris flows. The results show that five key modes in Luojiayu gully and two modes in Sanyanyu gully accounted for the scale amplification of downstream debris flows in the Zhouqu event. This study illustrates how the hazardous process of natural debris flows can begin several kilometers upstream as a complex cascade of geomorphic events (failure of landslide dams and erosion of the sloping bed) can scale to become catastrophic discharges. Neglecting recognition of these hazardous geomorphic and hydrodynamic processes may result in a high cost.

  12. 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.

  13. 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...

  14. Spirit Lake dam-failure flood routing assessment

    USGS Publications Warehouse

    Kresch, D.L.

    1985-01-01

    Potential clear-water floodflows resulting from uncontrolled breaching by Spirit Lake of a debris dam deposited by the May 18 , 1980, eruption of Mount St. Helens, Washington, were evaluated. U.S. Geological Survey dam-break model K-634 was utilized, first to compute clear-water flood hydrographs for various hypothetical breach scenarios, and then to hydraulically route them downstream to the mouth of the Toutle River. Dam-break computations were obtained for 12 breach-development scenarios. Eight of the scenarios modeled breaches caused by overtopping of the June 1982 crest of the debris dam, while the other four modeled breaches resulting from overtopping of the debris dam at a possible future crest altitude of 3,490 feet. Equal numbers of scenarios, six each, were modeled for breach development durations of 0.25 hour and 1.0 hour. Peak discharges and times of arrival at selected locations for scenarios with breach development durations of 1.0 hour are presented in tables. Peak discharges computed for dam-break scenarios with breach crest widths of 400 feet are almost twice the magnitude of those computed for scenarios identical in all other respects, but with widths of 200 feet. Peak discharges computed for breaches caused by overtopping of the debris dam at an altitude of 3,531.8 feet were generally found to be roughly five times greater than those caused by overtopping at an altitude of 3,490 feet, if the breaches had identical crest elevations and crest widths. Decreases in peak discharge from Spirit Lake to the mouth of the Toutle River ranged from 16 to 26 percent for the scenarios modeled. This lack of significant attenuation is primarily due to the large volume and surface area of Spirit lake (in excess of 360,000 acre-feet and 3,000 acres, respectively, for all scenarios modeled), which result in the continued discharge of high flows long after breach development is complete. The degree of attenuation is also minimized by the generally steep narrow valleys through which the North Fork Toutle and Toutle Rivers flow. Elapsed time from beginning of breach development to arrival of peak discharges at the mouth of the Toutle River ranged from 4.3 to 7.4 hours for the scenarios modeled. (USGS)

  15. 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.

  16. 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).

  17. Seismic analysis of the Par Pond Dam: Study of slope failure and liquefaction. Technical evaluation report

    SciTech Connect

    Simos, N.; Reich, M.

    1994-07-01

    Stability concerns of the Par Pond Dam, an embankment structure in the Savannah River Site complex, resulted in a comprehensive evaluation of the state of its integrity. Specifically, excessive seepage through the embankment, slope failure due to an earthquake event as well as liquefaction potential of the embankment and the foundation are addressed and the potential of failure is evaluated. Lastly, remedial benefits of the addition of a berm structure are also assessed.

  18. REPORT ON WORKSHOP ON ISSUES, RESOLUTIONS, AND RESEARCH NEEDS RELATED TO EMBANKMENT DAM FAILURE ANALYSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper summarizes the purpose, methodology, and outcomes of the June 2001 USDA/FEMA Workshop on Issues, Resolutions, and Research Needs Related to Embankment Dam Failure Analysis. The purpose of this workshop was to determine state of the practice, identify short-term and long-term research nee...

  19. 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.

  20. The formation and failure of debris flow-dams, background, key factors and model tests: case studies from China

    NASA Astrophysics Data System (ADS)

    Dang, Chao; Cui, Peng; Cheng, Zun-Lan

    2009-06-01

    Temporary dams can be formed by the sudden injection of debris flow into main streams by some favorable geomorphologic and hydraulic conditions, resulting in extensive inundations upstream and catastrophic floods downstream due to dam breaches and consequently dramatic changes of channels and valleys. Expeditious means of assessing dam-forming potential are necessary, particularly in geologically active regions. Complete blockages or dam formations are significantly related to the discharge ratio and velocity ratio between the tributary and the main stream, the bulk density of the debris flow, confluent angles and the degree of unevenness of grain sizes. In order to set up a critical index/ C for dam formation, 19 groups of flume tests were conducted. The results showed that there were three types of blockage in the intersections, and dam-forming processes were mainly controlled by the product of the dimensionless momentum ratio and the degree of unevenness of grain sizes in the debris flow. Complete blockages or dam formations occurred when C > 83.4, whereas semi-blockages were formed or no dams were formed when C < 71.5, which had been judged to be feasible by historical instances of dam formation in China. Dam failures commonly resulted from overtopping. No piping was observed in the course of dam failure, and the time elapsed between dams can be denoted by a linear relation with the momentum ratio.

  1. Statistical source identification of major and trace elements in groundwater downward the tailings dam of Miduk Copper Complex, Kerman, Iran.

    PubMed

    Kargar, Maryam; Khorasani, Neamatolah; Karami, Mahmoud; Rafiee, Gholamreza; Naseh, Reza

    2012-10-01

    Identifying the possible sources of potential harmful metals in groundwater systems plays a crucial role in evaluating the potential risks to residents and local plant cover. An attempt was made to define the origin of Al, Cd, Cu, Fe, Mo, Ni, and Pb in groundwater using multivariate statistic approaches [principal component analysis (PCA), hierarchical cluster analysis], and tailings sequential extraction by the method of Tessier et al. The concentrations of studied elements were measured in 42 samples collected from 15 stations surrounding and downward the tailings dam of Miduk Copper Complex, central province of Kerman, Iran. According to the PCA results, confirmed by cluster dendrogram and metal content measurement of tailings sequential extracts, two components accounting for nearly 73% of the total variance, controlled the heavy metal variability and classified the possible source of groundwater contamination into two categories: (1) upper seepage which controls the variability of Cd, Cu, Fe, Ni, and Pb and (2) toe seepage of tailings dump affecting on Mo and Al concentration in downstream groundwater. PMID:22048922

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

    NASA Astrophysics Data System (ADS)

    Mac√≠as, J. L.; Corona-Ch√°vez, P.; Sanch√©z-N√ļ√Īez, J. M.; Mart√≠nez-Medina, M.; Gardu√Īo-Monroy, V. H.; Garc√≠a-Tenorio, F.; Cisneros-M√°ximo, 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, Michoac√°n, 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.

  3. 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...

  4. 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.

    2014-07-01

    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 7 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 (>8į) to steep (>15į) 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.

  5. 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 (‚Č• 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 (‚ȧ 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¬į) to steep (> 15¬į) 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.

  6. 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) (ő¶75¬†mm¬†√ó¬†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¬†¬Ī¬†1.0¬†mg/kg (range: 1.9-4.6¬†mg/kg) and 321¬†¬Ī¬†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¬†¬Ī¬†0.5¬†mg/kg (range: 5.3-6.1¬†mg/kg) and 276¬†¬Ī¬†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¬†¬Ī¬†7.5 and 26.2¬†¬Ī¬†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

  7. Mineralogical characterization of tailing dams: incidence of abandoned mining works on soil pollution (Linares, Jaén)

    NASA Astrophysics Data System (ADS)

    de la Torre, M. J.; Hidalgo, C.; Rey, J.; Martínez, J.

    2012-04-01

    The metallogenic district of Linares-La Carolina (Jaén, Spain) consists of dyke mineralizations mainly of galena, accompanied by blende, chalcopyrite and barite. Associated to these abandoned mines, relatively extensive areas occupied by spoil heaps and tailing impoundments exist and constitute potential sources of soil pollution by metals and semimetals. In order to analyze the pollution potential of these mining wastes, we have carried out a mineralogical and geochemical study of seven tailing dams and surrounding soils in the area. The mineralogy of the samples was studied by x-ray diffraction (XRD) and scanning electron microscope (SEM). In addition, the total metal content of samples was determined by inductively coupled plasma mass spectrometry (ICP-MS) analysis. Samples were taken from the first 30 cm of the waste piles and soil deposits and white efflorescences were also obtained from the surface of the tailings. In all analyzed heaps, high to very high total contents in Pb (1220-22890 mg/kg), Zn (150-51280 mg/kg), Mn (2658-4160 mg/kg), Ba (1026-19610 mg/kg) and Fe (19400-138000 mg/kg) were observed. The concentrations for these same elements in the studied soils range from 527-9900 mg/kg for Pb, 27-1700 mg/kg for Zn, 506-2464 mg/kg for Mn, 2832-4306 for Ba and 8642-29753 mg/kg for Fe, and these figures indicate a contamination of the soils, according to the guidelines established by the Spanish law. The XRD and SEM results indicate that the tailings are primarily constituted by gangue of the exploited mineralization: quartz, calcite, ankerite, feldspars and phyllosilicates. They are inherited, primary mineral phases. Galena, also primary, appears in low proportion, as well as lepidocrocite, melanterite and cerussite, being these three last secondary minerals and indicating a certain remobilization of metal cations, especially lead and iron. On the other hand, quartz and phyllosilicates predominate in the soils, in which, in addition, is identified a little proportion of galena (primary mineral) and ferro-hexahydrite, also indicating mobilization of Fe. As regarding white surface blooms, they are formed mostly of magnesium sulphate with different hydration states. The morphology of these mineral precipitates reveals that they have been subject to cycle of washing and subsequent dehydration, which indicates that these phases present a great mobility in the environment, and they may be contributing to the transport of metals from the tailings into the surroundings soils.

  8. 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)

  9. 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.

  10. REPORT ON THE OUTCOMES OF A WORKSHOP ON ISSUES, RESOLUTIONS, AND RESEARCH NEEDS RELATED TO EMBANKMENT DAM FAILURE ANALYSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper summarizes the purpose, methodology, and outcomes of the June 2001 USDA/FEMA Workshop on Issues, Resolutions, and Research Needs Related to Embankment Dam Failure Analysis held in Oklahoma City, OK. The purpose of this workshop was to determine state of the practice, identify short-term ...

  11. An Analysis of Dissolved Oxygen Concentrations in Tail Waters of Hydroelectric Dams and the Implications for Small-Scale Hydropower Development

    NASA Astrophysics Data System (ADS)

    Cada, Glenn F.; Kumar, K. D.; Solomon, Jean A.; Hildebrand, Stephen G.

    1983-08-01

    One of the environmental issues affecting small-scale hydropower development in the United States is water quality degradation. The extent of this potential problem, as exemplified by low dissolved oxygen concentrations in reservoir tail waters, was analyzed by pairing operating hydroelectric sites with dissolved oxygen measurements from nearby downstream U.S. Geological Survey water quality stations. These data were used to calculate probabilities of noncompliance (PNC's), that is, the probabilities that dissolved oxygen concentrations in the discharge waters of operating hydroelectric dams will drop below 5 mg/l. The continental states were grouped into eight regions based on geographic and climatic similarities. Most regions had higher mean PNC's in summer than in winter, and summer PNC's were greater for large-scale than for small-scale hydropower facilities. Cumulative probability distributions of PNC also indicated that low dissolved oxygen concentrations in the tail waters of operating hydroelectric dams are phenomena largely confined to sites with large-scale facilities.

  12. 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

  13. 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.

  14. Combination of sequential chemical extraction and modelling of dam-break wave propagation to aid assessment of risk related to the possible collapse of a roasted sulphide tailings dam.

    PubMed

    Pérez-López, Rafael; Sáez, Reinaldo; Alvarez-Valero, Antonio M; Miguel Nieto, José; Pace, Gaetano

    2009-10-15

    The Sotiel-Coronada abandoned mining district (Iberian Pyrite Belt) produced complex massive sulphide ores which were processed by flotation to obtain Cu, Zn and Pb concentrates. The crude pyrite refuses were roasted for sulphuric acid production in a plant located close to the flotation site, and waste stored in a tailing dam. The present study was focused on the measurements of flow properties, chemical characterization and mineralogical determination of the roasted pyrite refuses with the aim of assessing the potential environmental impact in case of dam collapse. Chemical studies include the determination of the total contaminant content and information about their bio-availability or mobility using sequential extraction techniques. In the hypothetical case of the tailing dam breaking up and waste spilling (ca. 4.54Mt), a high density mud flow would flood the Odiel river valley and reach both Estuary of Huelva (Biosphere Reserve by UNESCO, 1983) and Atlantic Ocean in matter of a couple of days, as it was predicted by numerical simulations of dam-break waves propagation through the river valley based on quasi-2D Saint-Venant equations. The total amount of mobile pollutants that would be released into the surrounding environment is approximately of 7.1.10(4)t of S, 1.6.10(4)t of Fe, 1.4.10(4)t of As, 1.2.10(4)t of Zn, 1.0.10(4)t of Pb, 7.4.10(3)t of Mn, 2.2.10(3)t of Cu, 1.5.10(2)t of Co, 36t of Cd and 17t of Ni. Around 90-100% of S, Zn, Co and Ni, 60-70% of Mn and Cd, 30-40% of Fe and Cu, and 5% of As and Pb of the mobile fraction would be easily in the most labile fraction (water-soluble pollutants), and therefore, the most dangerous and bio-available for the environment. This gives an idea of the extreme potential risk of roasted pyrite ashes to the environment, until now little-described in the scientific literature. PMID:19683794

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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 en¬≠able 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 Atat√ľrk 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.

  1. Northwest Montana Libby/Hungry Horse Dams Wildlife Mitigation; Columbian Sharp-Tailed Grouse, 1990-1991 Final Report.

    SciTech Connect

    Cope, Michael G. |

    1992-07-01

    Distribution, habitat use and survival of transplanted Columbian sharp-tailed grouse in the Tobacco Plains, Montana were studied from April, 1990 to August, 1991. For transplant purposes, 12 grouse (5 female and 7 male) were trapped on dancing grounds near Douglas Lake, British Columbia, Canada during spring, 1990. In April, 1991, trapping of 4 female and 2 male grouse for transplant occurred on the Sand Creek Wildlife Management Area in southeast Idaho while 3 additional males were transplanted from Douglas Lake. Minimum annual survival of transplanted grouse in the Tobacco Plains is relatively high (47%). High survival is possibly due to 2 factors: (1) topography and habitat characteristics that discourage dispersal and (2) the presence of limited but relatively good habitat. Two of 18 radio-equipped grouse dispersed out of the study area, while 2 others survived in the area for over 590 days. A negative correlation in distances moved between consecutive relocations and length of survival was seen in radio-equipped grouse in this study. Data collected during this study showed the importance of habitat associated with the Dancing Prairie Preserve. Three of 5 females transplanted in 1990 attempted to nest after being released. Nesting and brood rearing sites were characterized by dense grass cover with an average effective height {ge}20 cm. Shrub cover was associated only with brood rearing sites. Overall habitat use by transplanted Columbian Sharp-tailed grouse showed an apparent avoidance of agricultural land and use of other habitat types in proportion to their availability.

  2. Probable hydrologic effects of a hypothetical failure of Mackay Dam on the Big Lost River Valley from Mackay, Idaho to the Idaho National Engineering Laboratory

    USGS Publications Warehouse

    Druffel, Leroy; Stiltner, Gloria J.; Keefer, Thomas N.

    1979-01-01

    Mackay Dam is an irrigation reservoir on the Big Lost River, Idaho, approximately 7.2 kilometers northwest of Mackay, Idaho. Consequences of possible rupture of the dam have long concerned the residents of the river valley. The presence of reactors and of a management complex for nuclear wastes on the reservation of the Idaho National Engineering Laboratory (INEL), near the river , give additional cause for concern over the consequences of a rupture of Mackay Dam. The objective of this report is to calculate and route the flood wave resulting from the hypothetical failure of Mackay Dam downstream to the INEL. Both a full and a 50 percent partial breach of this dam are investigated. Two techniques are used to develop the dam-break model. The method of characteristics is used to propagate the shock wave after the dam fails. The linear implicit finite-difference solution is used to route the flood wave after the shock wave has dissipated. The time of travel of the flood wave, duration of flooding, and magnitude of the flood are determined for eight selected sites from Mackay Dam, Idaho, through the INEL diversion. At 4.2 kilometers above the INEL diversion, peak discharges of 1,550.2 and 1,275 cubic meters per second and peak flood elevations of 1,550.3 and 1,550.2 meters were calculated for the full and partial breach, respectively. Flood discharges and flood peaks were not compared for the area downstream of the diversion because of the lack of detailed flood plain geometry. (Kosco-USGS)

  3. Zipingpu Concrete Face Rockfill Dam Failures caused by the 8.0R Earthquake on the 12th May 2008 (Chengdu, China)

    NASA Astrophysics Data System (ADS)

    Lekkas, E.

    2009-04-01

    The 8.0R earthquake that struck Sichuan on the 12th of May 2008, in the district of Chengdu of Southern China resulted in tenths of thousands casualties, the complete destruction of many towns and extended damages to public works. The earthquake was triggered by a reverse fault of NE-SW trend, more than 100 km long, that divides morphologically the affected area in two sections, the eastern one with mild low topography and the western one with intense relief representing the boundary of Tibet Mountains. This mountainous section is characterized by a rich drainage network that drains the greater region of the Tibet plateau. Along the trace of this high-stand for thousands of years numerous hydraulic works have been attempted in order to manage the water supply. Especially during the past decades, 400 small and large dams have been constructed. The main dam is the Zipingpu dam. It is a Concrete Face Rockfill Dam (CFRD) that has a height of 150m, a capacity of 1.2 billion m3 and includes a hydroelectric plant of 3.4 billion Kwh power. The Zipingpu dam is located 10km east of the earthquake epicenter and after the earthquake of 8.0R, the following failures were recorded: (i) Subsidence of the crown in the central part of the dam, of the order of 50cm in relation to the side survey control points, (ii) Deformation of the lower face of the dam, an area of approximately 1000 m2, (iii) Deviations and deformations of the construction elements throughout the face of the dam, (iv) Widening of construction joints (approximately 15 cm on the upper face), (v) Extended massive landslides throughout the reservoir, and (vi) Landslides on both left and right abutments of the dam causing further damages to secondary constructions. After the evaluation of the dam damages, the discharge of the reservoir was ordered through the emergency spillway in order to minimize the risk of a potential disaster for the nearby towns and especially Dujiangyan. Finally, the causes of the failures are investigated based on the available data.

  4. 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.

  5. Arsenic concentrations in soils impacted by dam failure of coal-ash pond in Zemianske Kostolany, Slovakia.

    PubMed

    Jurkovi?, L'ubomŪr; Hiller, Edgar; VeselskŠ, Veronika; Pet'kovŠ, KatarŪna

    2011-04-01

    In this study, the concentrations of arsenic were determined in the soils around old coal-ash pond. The soils in the study area were severely contaminated with arsenic after dam failure of the coal-ash pond. The mean concentrations of arsenic in soils collected from three sampling depths of 0-20, 20-40 and >40†cm were 173, 155 and 426†?g/g, respectively, exceeding greatly the Dutch intervention threshold for this element. Arsenic concentrations were positively correlated with total iron and aluminium contents in the soils (r†=†0.73, p†<†0.001 and r†=†0.72, p†<†0.001, respectively), indicating that oxyhydroxides of iron and aluminium may control the distribution of arsenic in these soils. Ammonium nitrate extractant was used to mimic availability of arsenic for plant uptake from the soils. Between 0.05 and 6.21% of the total soil arsenic were extracted using a†single extraction test and a significant positive correlation between soil leachate pH and arsenic extractability (r†=†0.70, p†<†0.01) was observed. This suggested that soil pH might play a role in the bioavailability of arsenic. PMID:21331534

  6. Elevations and discharges produced by a simulated flood wave on the lower Sabine River, Louisiana and Texas, caused by a theoretical dam failure

    USGS Publications Warehouse

    Neely, Braxtel L.; Stiltner, Gloria J.

    1979-01-01

    The Toledo Bend Reservoir is located on the lower Sabine River between Louisiana and Texas. Two mathematical models were coupled to calculate the flood wave that would result from the theoretical failure of 25 percent of Toledo Bend Dam and route the wave downstream to Orange, Tex. Computations assumed failure (1) at the peak of the 100-year flood when discharge of the Sabine River is 102,000 cubic feet per second and (2) when the average discharge is 10,000 cubic feet per second. Two techniques were used in the dam-break model. The method of characteristics was used to propagate the shock wave following dam failure. The linear implicit finite-difference solution was used to route the flood wave following shock wave dissipation. The magnitude of the flow was determined for Burkeville, Bon Wier, Ruliff, and Orange, Tex., along the lower Sabine River. For these sites, respectively, the following peak elevations were calculated: 119, 82, 31, and 13 feet for the 100-year flood and 110, 75, 27, and 9 feet for the average discharge. (Woodard-USGS)

  7. 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

    2015-12-01

    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

  8. 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 ‚Äúsource-pathway-target‚ÄĚ 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

  9. Nonlinear Aeroelastic Behavior of Tail / Rudder Systems with Freeplay and Actuator Failure

    NASA Astrophysics Data System (ADS)

    Noble, Matthew

    This thesis discusses the development of numerical simulations implemented in MATLAB and of an experimental tail/rudder model for the investigation of the effects of non-linearities on control surface flutter of a three-degree of freedom typical section airfoil. Non-linearities investigated include a structural non-linearity in the form of freeplay about the control surface hinge line as well as velocity-squared damping, simulating a failed actuator. The mathematical modeling, design, and testing of a prototype velocity-squared damper is also presented for use in the numerical simulations. In both cases, the describing function method has been used to predict the amplitudes of possible Limit-Cycle Oscillations (LCOs) in the rudder DOF. Response amplitudes and frequencies in the frequency domain, are shown to agree extremely well with results obtained in the time-domain via direct numerical integration of the equations of motion. Both stable and unstable limit-cycle behavior has been predicted, resulting in a detailed set of predictions for the response of the system below the flutter boundary.

  10. WinDAM C earthen embankment internal erosion analysis software

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two primary causes of dam failure are overtopping and internal erosion. For the purpose of evaluating dam safety for existing earthen embankment dams and proposed earthen embankment dams, Windows Dam Analysis Modules C (WinDAM C) software will simulate either internal erosion or erosion resulting f...

  11. Small dams need better management

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-03-01

    Many small dams around the world are poorly maintained and represent a safety hazard, according to Pisaniello et al. Better oversight of small dams is needed, the authors argue. The researchers reviewed literature, conducted case studies in four states in Australia, and developed policy benchmarks and best practices for small-dam management. Small dams, often just several meters high and typically privately owned by individual farmers, have historically caused major damage when they fail. For instance, in China in 1975, 230,000 people died when two large dams failed because of the cumulative failure of 60 smaller upstream dams. In the United States, in 1977 the 8-meter-high Kelly Barnes Lake dam failed, killing 39 people. Many other small-dam failures around the world have resulted in casualties and severe ecological and economic damage.

  12. 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.

  13. 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.

  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)

    RaŇ°ka, 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. 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...

  16. 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...

  17. 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...

  18. 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...

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

    DOEpatents

    Coteus, Paul W.; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Steinmacher-Burow, Burkhard D.

    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.

  20. 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.

  1. Lake Nyos Dam

    NASA Astrophysics Data System (ADS)

    Freeth, S. J.

    Lake Nyos, or to be more precise, the upper 38 m of Lake Nyos, is held back by a natural dam (Figure 1) which, if it were to fail, would wreak havoc in the valleys to the north and cause a serious flood to surge down the Katsina Ala into Nigeria. Lockwood et al., [1987], who have been investigating the Lake Nyos gas disaster, which killed an estimated 1700 people in August 1986, presented a paper on the potential for disastrous failure of the Lake Nyos dam to the AGU Fall Meeting. Part of what they said was subsequently reported in New Scientist (December 10, 1987, p. 18). They have placed on record their view that the dam is only 400 years old and are reported to have stated that it is eroding away at the alarming rate of 1.5 m/yr. If their figures are correct, then surely the dam will fail within a decade or two at the most, and there is indeed cause for alarm and immediate action. However, teams from Cameroon, France, Italy, Japan , Switzerland, Britain, Nigeria, and Germany also visited Lake Nyos in the immediate aftermath of the gas disaster, and none of their reports have suggested that the dam is in itself an imminent threat.

  2. [Profile variability of soil properties in check dam on the Loess Plateau and its functions].

    PubMed

    Wang, Yun-qiang; Zhang, Xing-chang; Han, Feng-peng

    2008-04-01

    To understand the profile variability of soil properties of check dam and its possibility of engineering control over non-point source pollution, we used classical statistics to characterize the profile change of soil properties of a 5.20 m depth soil profile in the typical check dam on the Loess Plateau. The roles of check dam as organic carbon storage and available nutrients storage were discussed. The results showed that: 1) The bulk density and sand content of dam-head were lower than dam-tail, while, soil water content, silt, loam, organic carbon, available P, NO3(-) -N and NH4+ -N were higher than dam-tail. The bulk density for both dam-head and dam-tail showed weak variability while other properties showed moderate variability. All variables followed a normal distribution except sand in dam-head and soil moisture in dam-tail. 2) The change pattern of soil moisture on the soil profile for both dam-head and dam-tail was saw-tooth type. The change trends of soil organic carbon, available P and NH4+ -N were comparable to that of soil moisture. 3) The correlations among soil water content, organic carbon, bulk density, silt, loam, sand, available P, NO3(-) -N and NH4+ -N were significant (p < 0.05) except the relationship between bulk density and NO3(-) -N, NH4+ -N and relationship between available P and NH4+ -N in dam-tail. The positive or negative correlation of soil properties both in dam-head and dam-tail were coincident. 4) The check dam can be an important carbon storage on the Loess Plateau, and the organic carbon storage in dam-head was higher than dam-tail. The storage of organic carbon in 400-520 cm depth was the biggest for dam-head, in 0-100 cm depths for dam-tail. 5) The check dam is an enrichment sink of available nutrients. The storage of available P, NO3(-) -N and NH4+ -N in dam-head were higher than dam-tail, and the range of storage was: NH4+ -N > available P > NO3(-) -N. The coefficient of enrichment for NH4+ -N and NO3(-) -N were 1.132 and 1.956, respectively. 6) As the sink of soil nutrients, check dam has an important theoretical value for region carbon balance, ecological environment reconstruction and the effective control over non-point source pollution. PMID:18637356

  3. 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)

  4. Garrison Dam

    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....

  5. 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

  6. Stability requirements for old embankment dams

    SciTech Connect

    James, R.L.; Jacoby, S.R.

    1995-12-31

    The relevance of minimum factor of safety criteria from static stability analyses of older embankment dams for assessing safety against catastrophic failure is reviewed. An alternative approach using documented performance and field inspection is suggested.

  7. 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

  8. 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. ...

  9. 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.

  10. Historic mills and mill tailings as potential sources of contamination in and near the Humboldt River basin, northern Nevada. Chapter D.

    USGS Publications Warehouse

    Nash, J. Thomas; Stillings, Lisa L.

    2003-01-01

    Reconnaissance field studies of 40 mining districts in and near the Humboldt River basin have identified 83 mills and associated tailings impoundments and several other kinds of mineral-processing facilities (smelters, mercury retorts, heap-leach pads) related to historic mining. The majority of the mills and tailings sites are not recorded in the literature. All tailings impoundments show evidence of substantial amounts of erosion. At least 11 tailings dams were breached by flood waters, carrying fluvial tailings 1 to 15 km down canyons and across alluvial fans. Most of the tailings sites are dry most of the year, but some are near streams. Tailings that are wet for part of the year do not appear to be reacting significantly with those waters because physical factors such as clay layers and hard-pan cement appear to limit permeability and release of metals to surface waters. The major impact of mill tailings on surface- water quality may be brief flushes of runoff during storm events that carry acid and metals released from soluble mineral crusts. Small ephemeral ponds and puddles that tend to collect in trenches and low areas on tailings impoundments tend to be acidic and extremely enriched in metals, in part through cycles of evaporation. Ponded water that is rich in salts and metals could be acutely toxic to unsuspecting animals. Rare extreme storms have the potential to cause catastrophic failure of tailings impoundments, carry away metals in stormwaters, and transport tailings as debris flows for 1 to 15 km. In most situations these stormwaters and transported tailings could impact wildlife but probably would impact few or no people or domes-tic water wells. Because all identified historic tailings sites are several kilometers or more from the Humboldt River and major tributaries, tailings probably have no measurable impact on water quality in the main stem of the Humboldt River.

  11. Hydrological Risk of Artificial Floods Associated To Dam Operations

    NASA Astrophysics Data System (ADS)

    de Michele, C.; Petaccia, A.; Rosso, R.

    Past experience and statistical data show that extreme floods are an important factor for risk assessment of dams. In the last century, the methods to assess the hydrolog- ical safety of dams have considered principally the analysis of dam-break scenarios. For instance, one records four major reservoir disasters in Italy; the first one (1923) was due to structural dam failure immediately after dam completion, the second one (1935) occurred because dam overtopping due to a flood largely exceeding spillway capacity, the third one (1963) was produced by the largest recorded landslide into a reservoir without dam failure, and the fourth one (1985) was caused by poor mainte- nance of a small fill dam. Yet in the last years, dam failures have been significantly reduced. Berga (1998) reported that the percentage of failures before 1950 was 2.3%, while for dams constructed from 1951 to 1982 it reduced to 0.2%, and since 1982 is only 0.09%. This considerable reduction indicates that a significant progress has been achieved in dam safety. On the other hand, there is an increasing need in modern risk- averse societies to reduce the vulnerability of downstream river systems. This includes economic damage to properties and infrastructures, priority of human life protection, and environmental damages. Therefore new criteria to evaluate the hydrological safety of dams are required also considering the effects of artificial floods generated by dam gate operation. In several countries, the major hazard is indeed not that associated with potential dam-breach, but it deals with the artificial floods produced by dam gate op- eration in both emergency and maintenance modes. The increase of anthropization of riparian areas downstream dams constructed in the past has augmented the potential effects of such operations. In this respect, one can note that emergency gates of the dams may release discharges largely exceeding natural extreme floods. The role of reservoir operation during major floods has been deeply questioned for a number of destructive floods in recent years, because of the possible enhancement of flood sever- ity due to emergency gate operation. In the present paper, we compare the "Design Flood" of 551 dams located in Italy with the potential flood which could be artificially generated through dam openings operation. This indicates that artificial floods must be included in hydrological risk assessment of dams. Accordingly, we introduce new criteria for dam classification under hazardous artificial floods.

  12. Correlation of serum IgG concentration in foals and refractometry index of the dam's pre- and post-parturient colostrums: an assessment for failure of passive transfer in foals.

    PubMed

    Korosue, Kenji; Murase, Harutaka; Sato, Fumio; Ishimaru, Mutsuki; Kotoyori, Yasumitsu; Nambo, Yasuo

    2012-11-01

    The object of this study was to evaluate the usefulness of measuring the differences in the values of the serum total protein (DVSTP) concentration of foals and the refractometry index (DVRI) of the milk of dams before and after nursing of the colostrum for assessing failure of passive transfer (FPT) in foals. Serum samples from 31 foals were collected before the first nursing and other 1 to 6 times between 4 and 24 hr after birth. Paired colostrum and milk samples were collected from 14 of their dams at the same time. Serum samples were analyzed for IgG concentration using a single radial immunodiffusion (SRID) test (98 samples) and total protein concentration using a temperature-compensating refractometer (98 samples). Colostrum and milk samples were analyzed for refractometry index (RI) using a Brix refractometer (71 samples). DVSTP concentration and DVRI were significantly correlated with serum IgG concentration. The negative predictive values (NPVs) of DVSTP concentration for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 98.2% and 91.3% when the cutoff value is set to 0.4 mg/dl and 0.8 mg/dl, respectively. Furthermore, the NPVs of DVRI for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 97.3% and 96.3% when the cutoff value is set to 6% and 10%, respectively. The results suggest that measurement of DVRI is useful in assessing FPT as an initial "stall-side" screening test, because it is easy, inexpensive to perform and allows for rapid interpretation. PMID:22785030

  13. Characteristics of large-sized landslide dams around the World

    NASA Astrophysics Data System (ADS)

    Iqbal, Javed; Dai, Fuchu; Xu, Ling; Xinbin, Tu

    2013-04-01

    Stability and failure mechanism of Large-sized landslide dams has become most important debate in the scientific community, as these dams are most hazardous in term of both property and human loss. Over 500 large-sized landslide dams from different countries of the world with volume > 1 x 105m3 have been reviewed. The factual data presented in this study shows that 58 % catastrophic landslides were triggered by earthquakes and 21 % by rainfall, revealing that earthquake and rainfall are two major triggers for more than ĺ fractions of large-sized landslide dams with the highest frequency during 1990s and 2000s all around the World. The mean landslide dam volume of the studied cases was 533.9 x 105m3 with mean dam height of 71 m, while the mean lake volume was 1566.2 x 105m3. Failure of these large landslide dams pose a severe threat to the property and people living downstream, hence the absolute attention is required to deal with this problem. A stability index (SI) has been derived on the basis of 65 large-sized landslide dams from different countries of the world with complete parametric information. Nevertheless, much work has been done on landslide dam failure prediction and mitigations measures by different researchers, however still there is a break in lithological studies of the landslide dams in terms of dam longevity. A lithological based classification of landslide dams have been proposed here which can be very helpful in subsequent studies in order to find out the accurate dam stability. 21 landslide dam types have been proposed on the basis of transported landslide material and surrounding lithology of the deposition area. Key words: Landslide dam, longevity, lithological studies, landslide frequency, classification.

  14. 75 FR 49429 - Metal and Nonmetal Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... 200 million gallons of water and tailings, inundating a hydraulic excavator in an adjacent pit. The... failure, the excavator operator had gone home and a bulldozer operator had parked his machine on the...

  15. 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.

  16. 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

  17. 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

  18. 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

  19. Focusing on dam safety

    SciTech Connect

    Lagassa, G.

    1993-01-01

    With increased relicensing activity and a federal emphasis on safety, dam repair and refurbishment is a growing business. Providers of goods and services are gearing up to meet the dam repair and rehabilitation needs that result.

  20. 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...

  1. 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…

  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. 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.

  4. Long-Term Stability of Pyroclastic Dams Around Mount Pinatubo

    NASA Astrophysics Data System (ADS)

    Tu√Īgol, N. M.; Tu√Īgol, N. M.; McKean, J. A.

    2001-12-01

    Many temporary lakes have been formed around Mount Pinatubo by the blockage of channels by lahar or pyroclastic-flow deposits. Many such pyroclastic dams have been observed to repeatedly form and breach, often resulting in catastrophic lahars. A few, however, have survived for many years. We consider four conceivable mechanisms for the failure of pyroclastic dams: (1) erosion of the dam by flows along the lahar channel; (2) gravitational collapse and/or piping; (3) lake overtopping; and (4) secondary hydroeruptions. Upper reaches of lahar channels, within about 15 km from the crater, are prone to rapid changes in channel configuration. Up to tens of meters of vertical and lateral erosion by lahars in these near-source areas have been observed to occur in hours. Pyroclastic dams formed in these areas are therefore likely to be removed or undermined by flows along the blocking lahar channel. Infinite-slope stability analysis indicates that pyroclastic dams are generally stable against gravitational slope collapse, owing largely to their long (typically few kilometers), gentle (<5%) downstream faces. The gentle slope and unconfined groundwater denote exit gradients for subsurface water far less than the critical hydraulic gradient of the dam material, thus rendering piping failure unlikely. Boundary shear stress considerations, supported by field observations, show high streambed mobility of channels on pumiceous deposits, mainly due to the dominantly sand-sized composition and low density of the deposits. Similarly composed pyroclastic dams are prone to rapid breach erosion by overtopping flows. However, material lost to erosion along the breach-channel may be compensated for by sediments delivered onto the dam by lahars and/or local runoff. This is easily achieved where the dam is in an aggrading environment, as in an active lahar fan. Once sediment supply to the dam is cut off, e.g., due to the depletion of source sediments, by revegetation, or by stream beheading, the dam is predicted to fail by breach erosion. It can thus be expected that, barring engineering intervention, all pyroclastic dams around Mount Pinatubo will eventually fail, as suggested by their absence before the 1991 eruptions. Secondary hydroeruptions and secondary pyroclastic flows/avalanches have been known to accompany the breaching of pyroclastic dams, where the dams are partially or wholly formed by hot pyroclastic flows. These phreatic phenomena may trigger dam-breaching, or they may occur once breach erosion has reached the hot sections of the dam deposits. If they do occur, they invariably accelerate breaching. The above analyses, though, show that they are not required for pyroclastic dams to fail.

  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. 13. AVALON DAM SUSPENSION BRIDGE TO CREST OF DAM ...

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

    13. AVALON DAM - SUSPENSION BRIDGE TO CREST OF DAM SHOWING PROXIMITY TO GUARD HOUSE. VIEW TO NORTH - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  7. 20. AVALON DAM DOWNSTREAM FACE OF DAM FROM ACROSS ...

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

    20. AVALON DAM - DOWNSTREAM FACE OF DAM FROM ACROSS OUTLET WORKS CHANNEL. VIEW TO NORTHWEST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  8. 23. AVALON DAM CREST AND DOWNSTREAM FACE OF DAM ...

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

    23. AVALON DAM - CREST AND DOWNSTREAM FACE OF DAM SHOWING PROXIMITY OF OUTLET WORKS AND GATE KEEPER'S COMPLEX. VIEW TO EAST-SOUTHEAST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  9. 21. AVALON DAM NORTH LEG OF DAM AND PARTIAL ...

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

    21. AVALON DAM - NORTH LEG OF DAM AND PARTIAL VIEW OF SPILLWAY NO. 2. VIEW TO NORTHWEST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  10. 31. AVALON DAM OUTLET WORKS FROM CREST OF DAM ...

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

    31. AVALON DAM - OUTLET WORKS FROM CREST OF DAM INCLUDING SPILLWAY NO. 1 AND CYLINDER GATE DISCHARGE PORTALS. VIEW TO SOUTHEAST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  11. 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

  12. Glen Canyon Dam

    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...

  13. Garrison Dam and Spillway

    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....

  14. Garrison Dam and Spillway

    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....

  15. 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…

  16. 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...

  17. Maple River Dam Spillway

    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...

  18. 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.

  19. Fish assemblage response to a small dam removal in the Eightmile River system, Connecticut, USA.

    PubMed

    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. PMID:25022888

  20. 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...

  1. 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

  2. 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.

  3. Plugs or flood-makers? the unstable landslide dams of eastern Oregon

    USGS Publications Warehouse

    Safran, Elizabeth B.; O'connor, James; Ely, Lisa L.; House, Kyle; Grant, Gordon E.; Harrity, Kelsey; Croall, Kelsey; Jones, Emily

    2015-01-01

    Landslides into valley bottoms can affect longitudinal profiles of rivers, thereby influencing landscape evolution through base-level changes. Large landslides can hinder river incision by temporarily damming rivers, but catastrophic failure of landslide dams may generate large floods that could promote incision. Dam stability therefore strongly modulates the effects of landslide dams and might be expected to vary among geologic settings. Here, we investigate the morphometry, stability, and effects on adjacent channel profiles of 17 former and current landslide dams in eastern Oregon. Data on landslide dam dimensions, former impoundment size, and longitudinal profile form were obtained from digital elevation data constrained by field observations and aerial imagery; while evidence for catastrophic dam breaching was assessed in the field. The dry, primarily extensional terrain of low-gradient volcanic tablelands and basins contrasts with the tectonically active, mountainous landscapes more commonly associated with large landslides. All but one of the eastern Oregon landslide dams are ancient (likely of order 103¬†to 104¬†years old), and all but one has been breached. The portions of the Oregon landslide dams blocking channels are small relative to the area of their source landslide complexes (0.4‚Äď33.6¬†km2). The multipronged landslides in eastern Oregon produce marginally smaller volume dams but affect much larger channels and impound more water than do landslide dams in mountainous settings. As a result, at least 14 of the 17 (82%) large landslide dams in our study area appear to have failed cataclysmically, producing large downstream floods now marked by boulder outwash, compared to a 40‚Äď70% failure rate for landslide dams in steep mountain environments. Morphometric indices of landslide dam stability calibrated in other environments were applied to the Oregon dams. Threshold values of the Blockage and Dimensionless Blockage Indices calibrated to worldwide data sets successfully separate dam sites in eastern Oregon that failed catastrophically from those that did not. Accumulated sediments upstream of about 50% of the dam sites indicate at least short-term persistence of landslide dams prior to eventual failure. Nevertheless, only three landslide dam remnants and one extant dam significantly elevate the modern river profile. We conclude that eastern Oregon's landslide dams are indeed floodmakers, but we lack clear evidence that they form lasting plugs.

  4. Columbia Canal dam rehabilitation

    SciTech Connect

    Moore, W.E. )

    1989-01-01

    This paper describes the construction of the Columbia Canal diversion dam. The history of the canal's location is outlined. The author presents the rehabilitation of the canal and the present status of the rehabilitation project.

  5. Hoover Dam Intake Towers

    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....

  6. 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.

  7. Dams and Intergovernmental Transfers

    NASA Astrophysics Data System (ADS)

    Bao, X.

    2012-12-01

    Gainers and Losers are always associated with large scale hydrological infrastructure construction, such as dams, canals and water treatment facilities. Since most of these projects are public services and public goods, Some of these uneven impacts cannot fully be solved by markets. This paper tried to explore whether the governments are paying any effort to balance the uneven distributional impacts caused by dam construction or not. It showed that dam construction brought an average 2% decrease in per capita tax revenue in the upstream counties, a 30% increase in the dam-location counties and an insignificant increase in downstream counties. Similar distributional impacts were observed for other outcome variables. like rural income and agricultural crop yields, though the impacts differ across different crops. The paper also found some balancing efforts from inter-governmental transfers to reduce the unevenly distributed impacts caused by dam construction. However, overall the inter-governmental fiscal transfer efforts were not large enough to fully correct those uneven distributions, reflected from a 2% decrease of per capita GDP in upstream counties and increase of per capita GDP in local and downstream counties. This paper may shed some lights on the governmental considerations in the decision making process for large hydrological infrastructures.

  8. Usoi Dam (Tajikistan) the highest landslide dam on the world

    NASA Astrophysics Data System (ADS)

    Roje-Bonacci, Tanja

    2014-05-01

    Natural dams an integral part of the landscape formation. They are formed when the soil from slopes blocks the watercourse. The development of such dam may lead to two rare but desirable extreme outcomes: quick easing of the new dam and leakage of water accumulated behind it or stabilization of the dam and the establishment of a permanent outflow of water from the newly formed lake before it overflows the dam. All outcomes between these two extremes pose a threat commonly resulting in catastrophic floods causing massive damage to the flooded areas. The largest known dam of this kind, more than 500 m high and existing already 100 years, is the Usoi Dam in Tajikistan. The dam is located in the Amur Darya river basin.

  9. 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

  10. Garrison Dam and Garrison Dam National Fish Hatchery

    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....

  11. 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

  12. 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.

  13. 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.

  14. Glen Canyon Dam

    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...

  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. Elwha Dam-removal

    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...

  17. 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.

  18. 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.

  19. Simulation on particle crushing of tailings material under high pressure

    NASA Astrophysics Data System (ADS)

    Liu, Hai-ming; Liu, Yi-ming; Yang, Chun-he; Cao, Jing

    2013-06-01

    With continuous increase of the high tailings dam, it has an important practical and theoretical significance to study the mechanical characteristics of the tailings material under high pressures. It is indicated that strength envelopes of the tailings material have a remarkable nonlinear characteristics through the triaxial test under high pressures. A further study stated that the particle crushing has a critical effect on the mechanical behavior of the tailings material. In order to quantitatively research its influence, the grain size distribution of the tailings material is analyzed for pre-and post-test and the particle crushing of the tailings material is measured. The particle flow code is employed to simulate and monitor the sample during testing. Firstly, a model which considers the particle crushing is built under the plane strain condition. Then, a series of biaxial numerical tests of the tailings specimen are simulated by using the model. It is found that the simulation result agrees with the triaxial test. Finally, a law between the particle crushing and strain of the tailings material under different confining pressures is obtained.

  20. Heart Failure

    MedlinePlus

    ... version of this page please turn Javascript on. Heart Failure What is Heart Failure? In heart failure, the heart cannot pump enough ... failure often experience tiredness and shortness of breath. Heart Failure is Serious Heart failure is a serious and ...

  1. 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¬į 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.

  2. 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).

  3. 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.

  4. Theseus Tail Being Unloaded

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The tail of the Theseus prototype research aircraft is seen here being unloaded at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

  5. Initial Geomorphic Responses to Removal of Milltown Dam, Clark Fork River, Montana, USA

    NASA Astrophysics Data System (ADS)

    Wilcox, A. C.; Brinkerhoff, D.; Woelfle-Erskine, C.

    2008-12-01

    The removal of Milltown Dam on the Clark Fork River, Montana, USA, is creating a field-scale experiment on upstream and downstream responses to dam removal and on how gravel-bed rivers respond to sediment pulses. Milltown Dam was removed in 2008, reconnecting the Clark Fork River to its upstream basin in terms of sediment transport and fish passage. This dam removal is especially notable because (1) it is the largest dam removal to date in the United States in terms of the volume of reservoir sediment potentially available for downstream transport (over 3 million m3; 1.7 million m3 are being mechanically removed); and (2) the dam is the downstream end of the largest Superfund site in the United States, the Clark Fork Complex, and reservoir sediments are composed largely of contaminated mine tailings. Data collection on pre- and post-dam removal channel morphology, bed sediment characteristics, and sediment loads are being used to investigate spatial and temporal patterns of sediment transport and deposition associated with this dam removal. In the first several months following breaching of the dam, snowmelt runoff with a 3-year recurrence interval peak caused substantial erosion and downstream transport of metals-laden sediments from Milltown reservoir. Reservoir sediments in the Clark Fork arm of Milltown reservoir eroded at levels far exceeding modeling predictions as a result of both incision to the new base level created by dam removal and bank retreat of over 200 m in reaches upstream of a constructed bypass reach and remediation area. Copper and other metals in these eroded reservoir sediments provide a tracer for identifying whether sediment deposits observed downstream of the dam originated from Milltown reservoir or uncontaminated tributaries and indicate that Milltown sediments have reached over 200 km downstream. Downstream deposition has been greatest along channel margins and in side-channel areas, whereas the transport capacity of the active channel has limited channel changes there.

  6. 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).

  7. Experimental Study of Overtopping Induced Landslide Dam Break Flow and Two Layer Two Phase Mixture Model

    NASA Astrophysics Data System (ADS)

    Liu, L.; Duan, J. G.; Zhong, D.; Zhang, H.

    2013-12-01

    A series of experiments were conducted to investigate flood flow generated by the failure of landslide dams due to overtopping. These experiments aim to quantify the influences of inflow discharge, downstream slope, width of dam crest, dam height, and dam material on the flood flow. Images from high-speed cameras are used to determine the profiles of dam body and flow discharge during the failure processes. Results showed that the water level in the upstream reservoir and the erosion of dam body are the dominant factors affecting the downstream flood flow. A physical-based model is established to calculate the arriving time and the peak discharge of dam break flow using two phase mixture model. Both analytical and numerical solutions were derived for the model. The modelling results were verified using data from this and several other laboratory experimental datasets. The agreement between the calculated and measured data showed the applicability of the proposed model for predicting the peak discharge of overtopping induced dam break flow.

  8. 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‚Äď780 ka and 250‚Äď70 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 (‚ȧ1.7 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.

  9. Tubes at Glen Canyon Dam

    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...

  10. 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.

  11. Synthesizing Studies of Dam Removal

    NASA Astrophysics Data System (ADS)

    O'Connor, Jim; East, Amy

    2014-10-01

    Dam decommissioning is rapidly emerging as an important river restoration strategy in the United States. Hundreds of dams have been removed in the past few decades, including several large ones (>10-15 meters) impounding large sediment volumes (>106 cubic meters) in the past 3 years, notably Condit Dam and the Elwha River dams in Washington State. These removals and the associated studies provide for the first time an opportunity to evaluate the immediate and persistent consequences of these significant fluvial‚ÄĒand in some cases, coastal‚ÄĒperturbations. Understanding dam removal response not only improves understanding of landscape and ecosystem adjustment to profound sediment pulses but also provides important lessons for future watershed restoration efforts.

  12. Hydromechanical Analysis of Masonry Gravity Dams and their Foundations

    NASA Astrophysics Data System (ADS)

    Bretas, Eduardo M.; Lemos, José V.; Lourenço, Paulo B.

    2013-03-01

    A numerical model for the hydromechanical analysis of masonry dams based on the discrete element method is presented. The dam and the rock foundation are represented as block assemblies, and a coupled flow-stress analysis is performed in an integrated manner for the entire system. Complex block shapes may be obtained by assembling elementary blocks into macroblocks, allowing the application of the model to situations ranging from equivalent continuum to fully discontinuum analysis. A contact formulation was developed based on an accurate edge-edge approach, incorporating mechanical and hydraulic behavior. The main numerical aspects are described, with an emphasis in the flow analysis explicit algorithm. An application to an existing masonry dam is presented, analyzing its present condition, with excessive seepage, and the proposed rehabilitation intervention. An evaluation of sliding failure mechanisms was also performed, showing the expected improvement in the safety of the structure.

  13. The Tail of BPM

    NASA Astrophysics Data System (ADS)

    Kruba, Steve; Meyer, Jim

    Business process management suites (BPMS's) represent one of the fastest growing segments in the software industry as organizations automate their key business processes. As this market matures, it is interesting to compare it to Chris Anderson's 'Long Tail.' Although the 2004 "Long Tail" article in Wired magazine was primarily about the media and entertainment industries, it has since been applied (and perhaps misapplied) to other markets. Analysts describe a "Tail of BPM" market that is, perhaps, several times larger than the traditional BPMS product market. This paper will draw comparisons between the concepts in Anderson's article (and subsequent book) and the BPM solutions market.

  14. Estimating tail probabilities

    SciTech Connect

    Carr, D.B.; Tolley, H.D.

    1982-12-01

    This paper investigates procedures for univariate nonparametric estimation of tail probabilities. Extrapolated values for tail probabilities beyond the data are also obtained based on the shape of the density in the tail. Several estimators which use exponential weighting are described. These are compared in a Monte Carlo study to nonweighted estimators, to the empirical cdf, to an integrated kernel, to a Fourier series estimate, to a penalized likelihood estimate and a maximum likelihood estimate. Selected weighted estimators are shown to compare favorably to many of these standard estimators for the sampling distributions investigated.

  15. 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

  16. Arsenic and heavy metals in native plants at tailings impoundments in Queretaro, Mexico

    NASA Astrophysics Data System (ADS)

    Santos-Jallath, José; Castro-Rodríguez, Alejandrina; Huezo-Casillas, José; Torres-Bustillos, Luis

    Ten native plants species that grow in three tailings dams from Ag, Pb, Cu and Zn mine in Queretaro, Mexico were studied. Total concentrations in tailings were 183-14,660 mg/kg As, 45-308 mg/kg Cd, 327-1754 mg/kg Pb, 149-459 mg/kg Cu and 448-505 mg/kg Zn. In the three tailings dams, the solubility of these elements is low. Tailings in dam 1 are acid generating while tailings in dams 2 and 3 are not acid-generating potential. Plants species that accumulate arsenic and heavy metals was identified; Nicotina glauca generally presented the highest concentrations (92 mg/kg As, 106 mg/kg Cd, 189 mg/kg Pb, 95 mg/kg Cu and 1985 mg/kg Zn). Other species that accumulate these elements are Flaveria pubescens, Tecoma stans, Prosopis Sp, Casuarina Sp and Maurandia antirrhiniflora. Two species were found that accumulates a large amount of metals in the root, Cenchrus ciliaris and Opuntia lasiacantha. Concentrations in soils in which plants grow were 488-5990 mg/kg As, 5-129 mg/kg Cd, 169-3638 mg/kg Pb, 159-1254 mg/kg Cu and 1431-13,488 mg/kg Zn. The Accumulation Factor (AF) determined for plants was less than 1, with exception of N. glauca for Cd. The correlation between arsenic and heavy metals found in soils and plants was low. Knowledge of plant characteristics allows it use in planning the reforestation of tailings dams in controlled manner. This will reduce the risk of potentially toxic elements are integrated into the food chain of animal species.

  17. Inspection of earthen embankment dams using time lapse electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Case, Jared S.

    According to the National Inventory of Dams (NID), the number of dams across the United States is approximately 85,000. Many of these dams are more than 50 years old and need vast attention to ensure their safety. It is difficult to obtain a full assessment of the dam just by visual inspections alone. This is because many problems associated with dam failure occur internally, which makes it difficult to be observed by the dam inspectors. Examples of these flaws are piping and seepage (flow of water through or around dam walls). It is in this area where geophysical methods can aid in obtaining a more confident evaluation of a dam's integrity. Electrical resistivity is one geophysical technique that would be useful in detecting internal flaws associated with seepage and piping because it is sensitive to moisture changes. A study is being conducted to examine the feasibility of electrical resistivity tomography (ERT) to map and monitor internal compromised zones within earthen embankment dams. Two quarter-scaled earthen embankment dams were built at the United States Department of Agriculture (USDA) Agriculture Research Service (ARS) Hydraulics and Engineering Research Unit (HERU) in Stillwater, Oklahoma. These two dams were constructed with known internal compromised zones that are susceptible to seepage and piping. Electrical resistivity surveys were conducted on the completed dams using a 56 electrode dipole-dipole array. The collected data was then processed using electrical resistivity tomography (ERT) imaging software and evidence of these two compromised zones was easily visible. Also, additional surveys were conducted in order to monitor the changes in electrical signatures associated with changes in these zones due to filling of the reservoir and environmental/climate changes.

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. Hoover Dam Intake Towers Panorama

    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....

  3. 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.

  4. 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 reproducibleófor sets of dams ranging in height from 0.55 m to 0.98 mówhen 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.

  5. 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.

  6. 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.

  7. States improve dam safety legislation and regulations

    SciTech Connect

    Spragens, L. )

    1993-05-01

    Several state dam safety agencies have helped their state governments pass new dam safety legislation of regulations during the past year. Improvements in the laws range from establishing or raising permit fees, to boosting requirements for professional licenses, to requiring emergency action plans for all significant and high-hazard dams. ASDSO tracks dam safety legislation and laws to help keep the association's members informed on progress in dam safety. In New Jersey, lawmakers passed legislation providing $1.7 million in loans for engineering studies on high-hazard dams. Similarly in Minnesota, lawmakers approved legislation providing $1.6 million for repair or removal of dams. In Colorado, new legislation creates an emergency dam repair cash fund for state engineers to cover costs of emergency actions. In South Carolina, the General Assembly passed major amendments to the Dams and Reservoirs Safety Act. The amendments require that dam owners notify the state within 30 days after title to a dam is transferred, and stipulate that owners of high-hazard and significant hazard dams prepare emergency action plans. The state also may require normal maintenance on a dam; previously, the dam had to be declared unsafe before and order could be issued. A number of other states are working on new legislation, guidelines, or regulations, including Massachusetts, New York, Washington, and Wyoming. Forty-eight states have dam safety legislation in place; Alabama and Delaware are without such legislation.

  8. Standing rectal and tail surgery.

    PubMed

    DeBowes, R M

    1991-12-01

    A variety of rectal, perirectal, and coccygeal surgeries can be performed in the standing equine patient if appropriate chemical and physical restraints are available and adequate regional anesthesia can be achieved. Some rectal tears and most rectal prolapses, mass lesions, perirectal abscesses, rectal biopsies, and selected injuries of the tail can be managed without prohibitive difficulty. Severe injuries that compromise the small colon cranial to the peritoneal reflection may require flank laparotomy, midline celiotomy, or humane euthanasia to manage the disease process effectively and appropriately. The foremost perioperative consideration beyond the use of effective restraint is the management of tenesmus in horses with rectal tears or prolapses. Medications to control bowel motility, epidural anesthesia, antiinflammatory analgesics, and topical compounds adequate to soothe and lubricate inflamed rectal tissues are an important adjunctive therapy in the aftercare of these surgical patients. Of nearly equal importance is the requirement that a loose fecal consistency be maintained with laxative diets, psyllium, and mineral oil. Failure to maintain a loose consistency of stool after treatment of these conditions may lead to rectal impaction or incisional dehiscence and surgical failure. PMID:1820231

  9. Performance of heterogeneous earthfill dams under earthquakes: optimal location of the impervious core

    NASA Astrophysics Data System (ADS)

    López-Querol, S.; Moreta, P. J. M.

    2008-01-01

    Earthfill dams are man-made geostructures which may be especially damaged by seismic loadings, because the soil skeleton they are made of suffers remarkable modifications in its mechanical properties, as well as changes of pore water pressure and flow of this water inside their pores, when subjected to vibrations. The most extreme situation is the dam failure due to soil liquefaction. Coupled finite element numerical codes are a useful tool to assess the safety of these dams. In this paper the application of a fully coupled numerical model, previously developed and validated by the authors, to a set of theoretical cross sections of earthfill dams with impervious core, is presented. All these dams are same height and have the same volume of impervious material at the core. The influence of the core location inside the dam on its response against seismic loading is numerically explored. The dams are designed as strictly stable under static loads. As a result of this research, a design recommendation on the location of the impervious core is obtained for this type of earth dams, on the basis of the criteria of minor liquefaction risk, minor soil degradation during the earthquake and minor crest settlement.

  10. 3. McMILLAN DAM UPSTREAM FACE OF DAM WITH NEW ...

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

    3. McMILLAN DAM - UPSTREAM FACE OF DAM WITH NEW RAILROAD BRIDGE IN BACKGROUND. VIEW TO NORTHWEST - Carlsbad Irrigation District, McMillan Dam, On Pecos River, 13 miles North of Carlsbad, Carlsbad, Eddy County, NM

  11. Elwha River Riparian Vegetation Response to Dams and Dam Removal

    NASA Astrophysics Data System (ADS)

    Shafroth, P. B.; Brown, R. L.; Clausen, A. J.; Chenoweth, J.

    2012-12-01

    Riparian vegetation is highly diverse and influences habitat of aquatic and terrestrial wildlife. Riparian vegetation dynamics are driven by stream flow regime, and fluxes of sediment and large woody debris, all of which can be altered by river damming. Dam removal is often implemented, in part, to help restore degraded riparian vegetation by reversing the alteration of these key drivers. However, increased disturbance and sediment flux associated with transport and exposure of trapped reservoir sediment can complicate a simple return to pre-dam conditions and can favor exotic species. We are studying the effects of dams and their removal on riparian vegetation along the Elwha River in Washington State, where removal of two large dams began in September 2011. To characterize vegetation composition, structure, and diversity prior to dam removal, we sampled 60-150 vegetation plots in 2004, 2005, and 2010 along five cross-valley transects in each of three river reaches: above both dams (upper reach), between the dams (middle reach), and downstream of both dams (lower reach). In summer 2012, we resampled a subset of our plots in the lower and middle reaches to evaluate vegetation and geomorphic change. We also sampled vegetation, topography, and grain size along newly-established transects within the exposed former reservoir behind Elwha Dam, which was removed in 2011 and 2012. Plant community distribution on bottomland geomorphic surfaces along the Elwha is typical of other systems in the region. We identified 8 overstory and 26 understory communities using multivariate analyses. Young bar surfaces (5-20 yrs) were dominated by willow, red alder, and black cottonwood. Floodplains and transitional fluvial terraces (<90yrs) were generally dominated by alder and cottonwood. Mature terraces (>90yrs) were often dominated by big-leaf maple. Douglas fir occurred on both young and old floodplains and terraces. Overstory species composition was more stable from 2005 to 2010 than understory, understory species composition was more influenced by reach than overstory, and understory communities on younger landforms were less stable. From 2005 to 2010, there was a 26% increase in species richness in the lower reach but no significant changes elsewhere. In both 2005 and 2010 there was a significant decrease in native species richness (26% and 30% respectively) from the furthest upstream to furthest downstream reach. Exotic species richness was significantly higher in the downstream reach compared to the upstream reach in both years. Following dam removal, we documented different pioneer plant communities growing on different surfaces within the former reservoir behind Elwha Dam. Some surfaces were dominated by exotic species of concern to resource managers, such as Canada thistle and reed canarygrass, while others contained typical, native pioneer communities dominated by willow, alder, and cottonwood. Along our existing monitoring transects, we documented some sediment deposition on channel margins, bars and low floodplain surfaces, particularly in the lower reach; relatively little new deposition occurred in the more armored and stable middle reach. Future monitoring will reveal changes to existing vegetation communities and development of new communities in the former reservoirs as removal of the upstream dam is completed and millions of m3 of sediment are redistributed.

  12. 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.

  13. Heart Failure

    MedlinePlus

    ... page from the NHLBI on Twitter. What Is Heart Failure? Heart failure is a condition in which the heart can' ... force. Some people have both problems. The term "heart failure" doesn't mean that your heart has stopped ...

  14. Managing 'tail liability'.

    PubMed

    Frese, Richard C; Weber, Ryan J

    2013-11-01

    To reduce and control their level of tail liability, hospitals should: Utilize a self-insurance vehicle; Consider combined limits between the hospital and physicians; Communicate any program changes to the actuary, underwriter, and auditor; Continue risk management and safety practices; Ensure credit is given to the organization's own medical malpractice program. PMID:24340649

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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

  20. Efficient utilization of washery tailings

    SciTech Connect

    Lyadov, V.V.; Litmanovich, I.M.

    1982-01-01

    The quality and quantity of coal recoverable from jigging machine tailings from the washeries at the Makeevha and Yasinovka Coke Works was investigated. Recleaning of tailings from these washeries can provide over 5 X 10/sup 5/ ton/year of coal suitable for use as an energy fuel. Tailings were processed using a dense medium separator.

  1. 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.

  2. 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)

  3. 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.

  4. 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.

  5. 76 FR 12094 - Whitman River Dam, Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... Federal Energy Regulatory Commission Whitman River Dam, Inc. Notice of Application Tendered for Filing.... Applicant: Whitman River Dam, Inc. e. Name of Project: Crocker Dam Hydro Project. f. Location: On the Whitman River, in the Town of Westminster, Worcester County, Massachusetts. The project would not...

  6. 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...

  7. 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 ...

  8. Middle Dam (Maine) Well Drilling

    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....

  9. 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...

  10. 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.

  11. Teton Dam flood of June 1976, Moody quadrangle, Idaho

    USGS Publications Warehouse

    Harenberg, William A.; Bigelow, Bruce B.

    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 Moody quadrangle. (Woodard-USGS)

  12. Teton Dam flood of June 1976, Rexburg quadrangle, Idaho

    USGS Publications Warehouse

    Harenberg, W.A.; Bigelow, B.B.

    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 on 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 Rexburg quadrangle. (Woodard-USGS)

  13. Teton Dam flood of June 1976, Menan Buttes quadrangle, Idaho

    USGS Publications Warehouse

    Thomas, Cecil A.; Ray, Herman A.; Harenberg, William A.

    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 Menan Buttes quadrangle. (Woodard-USGS)

  14. 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.

  15. Nonlinear Seismic Analysis of Morrow Point Dam

    SciTech Connect

    Noble, C R; Nuss, L K

    2004-02-20

    This research and development project was sponsored by the United States Bureau of Reclamation (USBR), who are best known for the dams, power plants, and canals it constructed in the 17 western states. The mission statement of the USBR's Dam Safety Office, located in Denver, Colorado, is ''to ensure Reclamation dams do not present unacceptable risk to people, property, and the environment.'' The Dam Safety Office does this by quickly identifying the dams which pose an increased threat to the public, and quickly completing the related analyses in order to make decisions that will safeguard the public and associated resources. The research study described in this report constitutes one element of USBR's research and development work to advance their computational and analysis capabilities for studying the response of dams to strong earthquake motions. This project focused on the seismic response of Morrow Point Dam, which is located 263 km southwest of Denver, Colorado.

  16. 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. ...

  17. Heart Failure

    MedlinePlus

    ... Above Heart Failure initiative. Living with HF and Managing Advanced HF Although it can be difficult to live with a chronic condition like heart failure, you can learn to manage the symptoms and live a full and enjoyable ...

  18. Respiratory Failure

    MedlinePlus

    Respiratory failure happens when not enough oxygen passes from your lungs into your blood. Your body's organs, such as ... need oxygen-rich blood to work well. Respiratory failure also can happen if your lungs can't ...

  19. Wind Tails Near Chimp

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image of the rock 'Chimp' was taken by the Sojourner rover's right front camera on Sol 72 (September 15). Fine-scale texture on Chimp and other rocks is clearly visible. Wind tails, oriented from lower right to upper left, are seen next to small pebbles in the foreground. These were most likely produced by wind action.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  20. 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.

  1. Diversion dam reduces decomposition, fungal biomass, and macroinvertebrate abundance and diversity: Implications for dam removal

    NASA Astrophysics Data System (ADS)

    Muehlbauer, J. D.; Lovett, J. M.; Jones, K. L.; Plichta, J. R.; Patrick, M. M.; Delaney, I. A.; Bennett, S. E.; Norman, P. A.; Flaccus, K. K.; Vlieg, J. A.; Leroy, C. J.; Marks, J. C.

    2005-05-01

    Dam decommissioning projects are rarely accompanied by adequate baseline data needed to test if the effects of dams are reversible. Although the effects of dams on aquatic species have been well-documented, there are few studies that document the effects of dams on ecosystem processes. In this study we examine how in-stream leaf litter processing rates and associated fungal and macroinvertebrate populations are affected by a dam in Fossil Creek, Arizona, which will be decommissioned in 2005. We found significantly faster decomposition rates above the dam accompanied by higher fungal biomass, invertebrate abundances and invertebrate diversity compared to below the dam. We predict that return of full flows will increase decomposition, fungal biomass, and secondary productivity in areas where flow is currently reduced. This study shows how diversion dams can inhibit ecosystem processes and provides data for testing the restoration potential of dam decommissioning on decomposition and decomposer communities.

  2. Heart Failure

    MedlinePlus

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... Tiredness and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  3. 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.

  4. Scale-dependency of macroinvertebrate communities: responses to contaminated sediments within run-of-river dams.

    PubMed

    Colas, Fanny; Archaimbault, Virginie; Devin, Simon

    2011-03-01

    Due to their nutrient recycling function and their importance in food-webs, macroinvertebrates are essential for the functioning of aquatic ecosystems. These organisms also constitute an important component of biodiversity. Sediment evaluation and monitoring is an essential aspect of ecosystem monitoring since sediments represent an important component of aquatic habitats and are also a potential source of contamination. In this study, we focused on macroinvertebrate communities within run-of-river dams, that are prime areas for sediment and pollutant accumulation. Little is known about littoral macroinvertebrate communities within run-of-river dam or their response to sediment levels and pollution. We therefore aimed to evaluate the following aspects: the functional and structural composition of macroinvertebrate communities in run-of-river dams; the impact of pollutant accumulation on such communities, and the most efficient scales and tools needed for the biomonitoring of contaminated sediments in such environments. Two run-of-river dams located in the French alpine area were selected and three spatial scales were examined: transversal (banks and channel), transversal x longitudinal (banks/channel x tail/middle/dam) and patch scale (erosion, sedimentation and vegetation habitats). At the patch scale, we noted that the heterogeneity of littoral habitats provided many available niches that allow for the development of diversified macroinvertebrate communities. This implies highly variable responses to contamination. Once combined on a global 'banks' spatial scale, littoral habitats can highlight the effects of toxic disturbances. PMID:21272919

  5. Maple River Dam Spillway Comparison

    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....

  6. Uranium mill tailings and radon

    SciTech Connect

    Hanchey, L A

    1981-04-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  7. Uranium mill tailings and radon

    SciTech Connect

    Hanchey, L A

    1981-01-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  8. Seismicity around Brazilian dam reservoirs

    SciTech Connect

    Coelho, P.E.F.P. )

    1987-01-01

    More than 30 cases of seismicity associated with dam reservoir sites are known throughout the world. Despite the lack of data in some areas, where seismicity occurred after reservoir impounding, there have been distinct seismic patterns observed in seismic areas after dam projects implantation. This has demonstrated that reservoir loading can trigger earthquakes. A mechanism of earthquake generation by reservoir impounding is proposed here with particular application to the Brazilian cases and to areas subject to low confining stress conditions in stable regions. Six artificial lakes are described and the associated earthquake sources are discussed in terms of natural or induced seismicity. Earthquake monitoring in Brazil up to 1967, when Brasilia's seismological station started operation, was mainly based in personal communications to the media. Therefore, there is a general lack of seismic records in relatively uninhabited areas, making it difficult to establish a seismic risk classification for the territory and to distinguish natural from induced seismicity. Despite this, cases reported here have shown an alteration of the original seismic stability in dam sites after reservoir loading, as observed by the inhabitants or records from Brasilia's seismological station. All cases appear to be related to an increase in pore pressure in permeable rocks or fracture zones which are confined between impermeable rock slabs or more competent rock. It is apparent that some cases show some participation of high residual stress conditions in the area.

  9. 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.

  10. Tailed bacteriophages: the order caudovirales.

    PubMed

    Ackermann, H W

    1998-01-01

    Tailed bacteriophages have a common origin and constitute an order with three families, named Caudovirales. Their structured tail is unique. Tailed phages share a series of high-level taxonomic properties and show many facultative features that are unique or rare in viruses, for example, tail appendages and unusual bases. They share with other viruses, especially herpesviruses, elements of morphogenesis and life-style that are attributed to convergent evolution. Tailed phages present three types of lysogeny, exemplified by phages lambda, Mu, and P1. Lysogeny appears as a secondary property acquired by horizontal gene transfer. Amino acid sequence alignments (notably of DNA polymerases, integrases, and peptidoglycan hydrolases) indicate frequent events of horizontal gene transfer in tailed phages. Common capsid and tail proteins have not been detected. Tailed phages possibly evolved from small protein shells with a few genes sufficient for some basal level of productive infection. This early stage can no longer be traced. At one point, this precursor phage became perfected. Some of its features were perfect enough to be transmitted until today. It is tempting to list major present-day properties of tailed phages in the past tense to construct a tentative history of these viruses: 1. Tailed phages originated in the early Precambrian, long before eukaryotes and their viruses. 2. The ur-tailed phage, already a quite evolved virus, had an icosahedral head of about 60 nm in diameter and a long non-contractile tail with sixfold symmetry. The capsid contained a single molecule of dsDNA of about 50 kb, and the tail was probably provided with a fixation apparatus. Head and tail were held together by a connector. a. The particle contained no lipids, was heavier than most viruses to come, and had a high DNA content proportional to its capsid size (about 50%). b. Most of its DNA coded for structural proteins. Morphopoietic genes clustered at one end of the genome, with head genes preceding tail genes. Lytic enzymes were probably coded for. A part of the phage genome was nonessential and possibly bacterial. Were tailed phages general transductants since the beginning? 3. The virus infected its host from the outside, injecting its DNA. Replication involved transcription in several waves and formation of DNA concatemers. Novel phages were released by burst of the infected cell after lysis of host membranes by a peptidoglycan hydrolase (and a holin?). a. Capsids were assembled from a starting point, the connector, and around a scaffold. They underwent an elaborate maturation process involving protein cleavage and capsid expansion. Heads and tails were assembled separately and joined later. b. The DNA was cut to size and entered preformed capsids by a headful mechanism. 4. Subsequently, tailed phages diversified by: a. Evolving contractile or short tails and elongated heads. b. Exchanging genes or gene fragments with other phages. c. Becoming temperate by acquiring an integrase-excisionase complex, plasmid parts, or transposons. d. Acquiring DNA and RNA polymerases and other replication enzymes. e. Exchanging lysin genes with their hosts. f. Losing the ability to form concatemers as a consequence of acquiring transposons (Mu) or proteinprimed DNA polymerases (phi 29). Present-day tailed phages appear as chimeras, but their monophyletic origin is still inscribed in their morphology, genome structure, and replication strategy. It may also be evident in the three-dimensional structure of capsid and tail proteins. It is unlikely to be found in amino acid sequences because constitutive proteins must be so old that relationships were obliterated and most or all replication-, lysogeny-, and lysis-related proteins appear to have been borrowed. However, the sum of tailed phage properties and behavior is so characteristic that tailed phages cannot be confused with other viruses. PMID:9891587

  11. EPRI dam safety workshop summary: Proceedings

    SciTech Connect

    Corso, R.

    1998-10-01

    The Electric Power Research Institute (EPRI) has an extensive history of working with utilities, federal and state agencies, consultants, and other interests to conduct a number of workshops and studies to improve the safety of dams. Through these efforts, EPRI has developed a number of tools to assist dam owners, particularly EPRI members, in the evaluation and modification of dams. Although a considerable amount of progress has been made toward improving dam safety, there remain among the over 75,000 dams in the US a significant number of structures that require in-depth evaluation and possible modifications. At the same time, there are pressures from several directions to prioritize dam safety issues and find cost-effective solutions to problems because there seems to be an ever-decreasing amount of funds to address dam safety. In that regard, EPRI is sensitive to those cost considerations in a changing utility environment. Therefore, EPRI recently entered into discussions with utilities, regulatory agencies, federal agencies (dam owners), and others interested in dam safety issues. From those discussions, a number of research ideas were developed, which were distilled into three primary topics and several secondary topics of importance. The three primary areas of concern included: penstocks, tunnels, and gates; instrumentation and monitoring; and post-tensioned anchors. This report will provide a review of the workshop and insight on ideas for future dam safety R and D.

  12. Modelling the impact of dam removal on geomorphic channel response and sediment delivery: an Austrian case study

    NASA Astrophysics Data System (ADS)

    PŲppl, Ronald; Coulthard, Tom; Keesstra, Saskia; Keiler, Margreth

    2015-04-01

    Dams are often considered to have the most significant impact on rivers as dam construction generally reduces downstream sediment fluxes which further involves geomorphic changes in the affected river reaches. Since many dams no longer fulfill their intended purpose (e.g. due to siltation), are dangerous (e.g. catastrophic dam failures) and/or are ecologically damaging (e.g. habitat destruction), within the last two decades several dams have been removed and many more are already proposed for removal. Unfortunately, there is still only little empirical knowledge about the geomorphic consequences of dam removals and the related sediment release which represents a big challenge for river management. Modelling is one way to approach this problem. In the presented study we modelled the impacts of dam removal on geomorphic channel processes, channel morphology and sediment delivery further considering the role of channel engineering measures and reservoir excavation within a river reach impacted by a series of dams using the landscape evolution model CAESAR-Lisflood. The model was run with data from a small catchment located in Lower Austria. Modelled geomorphic channel changes and sediment fluxes were spatio-temporally analyzed, related to real-world data and are discussed in the context of river management issues.

  13. 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, J√ľrgen; 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 ¬Ī 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.

  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. Hydrogeophysical investigations of the earthen Martis Creek Dam, Truckee, CA

    NASA Astrophysics Data System (ADS)

    Powers, M.; Minsley, B.; Bedrosian, P. A.; Burton, B.

    2008-12-01

    Martis Creek Dam, to the north of Lake Tahoe, was constructed for flood control in 1972 by the US Army Corp of Engineers. Since completion, all attempts to raise the level of Martis Creek Reservoir to its design level have been aborted due to seepage from locations downstream and along the west dam abutment. Following a recent evaluation, concerns have been raised regarding the potential for dam failure due to such seepage, combined with the consequences of failure on the growing population of Reno downstream. In response to these concerns, the US Geological Survey has undertaken a comprehensive suite of geophysical investigations aimed at understanding the interplay between geologic structure, seepage patterns, lake level, and ground-water levels. Investigations to date are focused upon a series of profiles, along which P- and S- wave reflection/refraction, DC resistivity, time-domain electromagnetic, and self- potential measurements have been made. Preliminary interpretation of coincident velocity, resistivity, and reflection sections suggests the dam rests upon a deep (>300 m) sedimentary section that interfingers with one or more volcanic flows derived from the Dry Lake Volcanic center to the east; this package has been subsequently offset by a NNW-trending fault of undetermined age and activity. Shallow resistivity sections further map glacial outwash deposits of variable thickness that cover most of the region to an average depth of 20-30 m. The ground-water level, as defined from seismic refraction sections, is depressed relative to current reservoir level and lies within sediments of the Truckee Formation that underlie the outwash deposits. The self-potential data are consistent with regional ground-water flow from south to north, as well as downhill flow from a topographic high on the right (east) abutment. The data show little indication of seepage through the dam from the reservoir, though this is likely due to the low reservoir level currently maintained. It is hypothesized that increased reservoir levels raise the local water table to or above the outwash/Truckee boundary, intersecting fluid transport pathways within the more permeable outwash deposits that connect to established seepage locations. The origin, extent, and connectivity of these inferred pathways, identified geophysically as disturbed zones within an otherwise homogeneous resistive layer, are the focus of follow-up studies involving extensive DC resistivity coverage.

  16. 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

  17. Runaway tails in magnetized plasmas

    NASA Technical Reports Server (NTRS)

    Moghaddam-Taaheri, E.; Vlahos, L.; Rowland, H. L.; Papadopoulos, K.

    1985-01-01

    The evolution of a runaway tail driven by a dc electric field in a magnetized plasma is analyzed. Depending on the strength of the electric field and the ratio of plasma to gyrofrequency, there are three different regimes in the evolution of the tail. The tail can be (1) stable with electrons accelerated to large parallel velocities, (2) unstable to Cerenkov resonance because of the depletion of the bulk and the formation of a positive slope, (3) unstable to the anomalous Doppler resonance instability driven by the large velocity anisotropy in the tail. Once an instability is triggered (Cerenkov or anomalous Doppler resonance) the tail relaxes into an isotropic distribution. The role of a convection type loss term is also discussed.

  18. GIS-based Mine Tailings Yield Mapping using RUSLE and Sediment Delivery Ratio

    NASA Astrophysics Data System (ADS)

    Kim, S.; Choi, Y.; Park, H.; Kwon, H.; Yoon, S.; Go, W.

    2010-12-01

    Erosion of mine tailings heaped up on the side of abandoned mine is an environmental problem because they contain harmful heavy metals. These harmful heavy metals such as copper, lead, arsenic in mine tailings cause contamination of surrounding streams and soil. To prevent and reduce the damage of surrounding streams caused by harmful heavy metals leaking from mine tailings, evaluating the pollution loading amount of mine tailings is required. However, it is difficult to assess its environmental impacts accurately because of its complex processes associated with it (Lal 1994). To estimate soil erosion and develop soil erosion management plans, there are some soil erosion estimation methods. Among these methods, the Revised Universal Soil Loss Equation (RUSLE) is the most widely used method. The six factors affecting soil loss such as rainfall-runoff erosivity, soil erodibility, slope length and steepness, cover management, and support practice were extracted from the spatial data and measurement data to evaluate average annual soil loss. Applying this model to mine tailings is possible, because mine tailings are regarded as soil. All the sediment generated may not be delivered at the watershed outlet because some of it may be deposited at various locations in the watershed. RUSLE does not consider the sediment delivery ratio to estimate the mine tailings delivered to the downstream point of interest. In this study, three methods are provided to compute the spatially distributed sediment delivery ratios and the results are compared with each other. Geographical Information System (GIS)-based erosion model and sediment delivery model were used to estimate the potential sediment yield from mine tailings in this study. The results achieved in this study can be used as basis data to assist mine tailings management and tailings dam installation plan. This work was supported by the Mine Reclamation Corporation funded by the Ministry of Knowledge Economy, Republic of Korea, the Brain Korea 21 Project, and the Research Institute of Engineering Science, Seoul National University, Korea.

  19. 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...

  20. [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.

  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. Defining Successful Dam Removal and Shifting the Focus of Restoration; A Midwest Perspective.

    NASA Astrophysics Data System (ADS)

    Selle, A. R.; Doyle, M. W.; Stanley, E. H.; Harbor, J. M.; Lyn, D. A.

    2002-12-01

    The number of dam removals in the US has increased in the last decade because design lives are being exceeded for an increasing number of dams, and because interest groups have pushed for removal as part of attempts to restore river ecology. Large numbers of small dams have been removed, despite the paucity of information regarding the physical and biological impacts of removal. Here we offer a Midwestern perspective on dam removal, based on issues endemic to rivers of this region. In the absence of comprehensive national studies of dam removal, regionally specific studies provide a starting point for the debate over the efficacy of dam removal as a river restoration tool. Three of the most important issues in Midwestern river management are; excessive nutrient export, endangered mussel populations, and high sediment inputs. Some of the most diverse assemblages of freshwater mussels reside in the Midwest. These populations have been historically impacted by over-harvesting and increased sediment inputs to lotic environments. Dam removal results in two impacts that operate against mussel populations. First, the rapid dewatering of the upstream reservoir can cause nearly total mortality of the upstream (impoundment) community. Second, large volumes of sediment are released and deposited into downstream reaches, effectively smothering downstream communities. Sediment deposition downstream exacerbates the well-documented negative impacts that years of poor land use have had on stream and river biota, thus not only does deposition impact mussel communities, but interferes with all aquatic communities. Closely related to the movement of sediment out of the former impoundment is the export of nutrients. Issues of eutrophication have been documented in water bodies ranging from small receiving lakes to the Gulf of Mexico. Removing a dam releases nutrients that have been stored for the duration of the dam's existence, allowing them to flow downstream in a concentrated release that can last long after the initial removal. All three key Midwestern river management issues are directly impacted by the removal of dams. Though few comprehensive studies have quantified specific impacts following removal, information from chance failure observations and unpublished documentation can be used to support the argument that dam removal evaluation should move away from perceived needs, such as restoring connectivity and opening up habitat for non-endangered aquatic species, toward other relevant regional issues. Given the importance of excessive nutrient export, endangered mussel populations, and high sediment inputs, they should be substantial components in defining the potential success of removal as a restoration option in the Midwest, and possibly other areas of the US.

  3. Heart Failure

    MedlinePlus

    ... to treat heart failure? Will I need a heart transplant? Is it safe for me to exercise? What kind of exercise should I do? Should I make any lifestyle changes at home to reduce my risk of complications? Source Reducing Readmissions for Congestive Heart Failure by RE Hoyt, CAPT, MC, USN, and ...

  4. 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

  5. 24. AVALON DAM GENERAL VIEW OF OUTLET WORKS CHANNEL ...

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

    24. AVALON DAM - GENERAL VIEW OF OUTLET WORKS CHANNEL AND UPSTREAM FACE OF DAM. VIEW TO WEST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  6. 4. AVALON DAM VIEW OF GATE KEEPER'S COMPLEX SHOWING ...

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

    4. AVALON DAM - VIEW OF GATE KEEPER'S COMPLEX SHOWING PROXIMITY OF DAM. VIEW TO WEST-NORTHWEST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  7. 2. AVALON DAM GENERAL VIEW OF SPILLWAY NO. 2 ...

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

    2. AVALON DAM - GENERAL VIEW OF SPILLWAY NO. 2 (LEFT), AVALON DAM (CENTER), AND OUTLET WORKS (RIGHT). vIEW TO WEST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 5. Downstream face of Rock Creek Diversion Dam, looking west ...

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

    5. Downstream face of Rock Creek Diversion Dam, looking west (Diversion into Irrigation District canal) - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  15. 3. Upstream face of Rock Creek Diversion Dam, closeup of ...

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

    3. Upstream face of Rock Creek Diversion Dam, close-up of gates, looking southeast - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  16. 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

  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. 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

  19. 10. BRIDGE IN CONTEXT OF DAM, THIRD POWER HOUSE IN ...

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

    10. BRIDGE IN CONTEXT OF DAM, THIRD POWER HOUSE IN FOREGROUND, LOOKING NORTH BY 360 DEGREES - Columbia River Bridge at Grand Coulee Dam, Spanning Columbia River at State Route 155, Coulee Dam, Okanogan County, WA

  20. 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

  1. 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

  2. 138. VIEW OF WESTERN APPROACH TO THE DAM, SHOWING DECORATIVE ...

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

    138. VIEW OF WESTERN APPROACH TO THE DAM, SHOWING DECORATIVE LAMP PYLONS FLANKING THE ENTRANCE AND THE PARAPET WALLS ON TOP OF DAM, LOOKING SOUTH (January 1991) - Coolidge Dam, Gila River, Peridot, Gila County, AZ

  3. View of upstream face of Lake Sabrina Dam showing the ...

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

    View of upstream face of Lake Sabrina Dam showing the redwood planks and base of dam from Lake Sabrina Basin, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  4. View of Lake Sabrina Dam downstream face from parking lot ...

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

    View of Lake Sabrina Dam downstream face from parking lot showing concrete outlet structure on tow of dam at left edge of photo, view southeast - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  5. 24. VIEW OF DAM ROLLER GATE BULKHEADS, BULKHEAD CARS AND ...

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

    24. VIEW OF DAM ROLLER GATE BULKHEADS, BULKHEAD CARS AND TRACKS IN STORAGE YARD, WITH MOVABLE CRANE AND DAM BRIDGE IN BACKGROUND, LOOKING WEST - Upper Mississippi River 9-Foot Channel Project, Lock & Dam No. 3, Red Wing, Goodhue County, MN

  6. 4. DETAIL VIEW OF DAM, SHOWING ROLLER GATES, GATE PIERS, ...

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

    4. DETAIL VIEW OF DAM, SHOWING ROLLER GATES, GATE PIERS, HEADHOUSES AND DAM BRIDGE, LOOKING NORTH, UPSTREAM - Upper Mississippi River 9-Foot Channel Project, Lock & Dam No. 3, Red Wing, Goodhue County, MN

  7. 2. OVERALL VIEW OF DAM, SHOWING CREST AND DOWNSTREAM FACE, ...

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

    2. OVERALL VIEW OF DAM, SHOWING CREST AND DOWNSTREAM FACE, WITH CONCRETE EXTENSION IN FOREGROUND, LOOKING NORTH - High Mountain Dams in Bonneville Unit, Fire Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

  8. 2. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING EAST ...

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

    2. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING EAST - High Mountain Dams in Upalco Unit, White Miller Lake Dam, Ashley National Forest, 6.9 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  9. 4. VIEW SHOWING DOWNSTREAM FACE OF DAM, LOOKING NORTHWEST ...

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

    4. VIEW SHOWING DOWNSTREAM FACE OF DAM, LOOKING NORTHWEST - High Mountain Dams in Upalco Unit, White Miller Lake Dam, Ashley National Forest, 6.9 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  10. 3. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING WEST ...

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

    3. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING WEST - High Mountain Dams in Upalco Unit, White Miller Lake Dam, Ashley National Forest, 6.9 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  11. 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.

  12. 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.

  13. 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.

  14. Quantitation of Dam methyltransferase in Escherichia coli.

    PubMed

    Boye, E; Marinus, M G; L√łbner-Olesen, A

    1992-03-01

    An antiserum against Escherichia coli Dam methyltransferase has been developed in rabbits and employed to detect and quantitate the enzyme in immunoblots. A wild-type, rapidly growing E. coli cell (doubling time = 30 min) was found to contain about 130 molecules of Dam methyltransferase. PMID:1537808

  15. 75 FR 62024 - Metal and Nonmetal Dams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... an Advance Notice of Proposed Rulemaking (75 FR 49429) asking interested parties to comment on... Safety and Health Administration 30 CFR Parts 56 and 57 RIN 1219-AB70 Metal and Nonmetal Dams AGENCY..., operation, and maintenance of safe dams which can assure miners are protected from the hazards of...

  16. Tiger Dams Reinforce Baton Rouge Levees

    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...

  17. 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...

  18. 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

  19. Groundwater Forecasting Optimization Pertain to Dam Removal

    NASA Astrophysics Data System (ADS)

    Brown, L.; Berthelote, A. R.

    2011-12-01

    There is increasing interest in removing dams due to changing ecological and societal values. Groundwater recharge rate is closely connected to reservoir presence or absence. With the removal of dams and their associated reservoirs, reductions in groundwater levels are likely to impact water supplies for domestic, industrial and agricultural use. Therefore accessible economic and time effective tools to forecast groundwater level declines with acceptable uncertainty following dam removals are critical for public welfare and healthy regional economies. These tools are also vital to project planning and provide beneficial information for restoration and remediation managements. The standard tool for groundwater forecasting is 3D Numerical modeling. Artificial Neural Networks (ANNs) may be an alternative tool for groundwater forecasting pertain to dam removal. This project compared these two tools throughout the Milltown Dam removal in Western Montana over a five year period. It was determined that ANN modeling had equal or greater accuracy for groundwater forecasting with far less effort and cost involved.

  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. Efficient utilization of washery tailings

    SciTech Connect

    Lyadov, V.V.; Litmanovich, I.M.

    1982-05-01

    The possibility of building a plant in Makeevka for the utilization of jigging machine tailings from the Yasinovka and Makeevka Coke Works washeries for production of lightweight concrete fillers and wall materials is being investigated.

  2. 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.

  3. Congenital transmission of Neospora caninum in white-tailed deer (Odocoileus virginianus).

    PubMed

    Dubey, J P; Jenkins, M C; Kwok, O C H; Ferreira, L R; Choudhary, S; Verma, S K; Villena, I; Butler, E; Carstensen, M

    2013-09-23

    Neosporosis is an important cause of bovine abortion worldwide. Many aspects of transmission of Neospora caninum in nature are unknown. The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoirs of N. caninum in the USA. During the hunting seasons of 2008, 2009, and 2010, brains of 155 white-tailed deer fetuses were bioassayed in mice for protozoal isolation. Viable N. caninum (NcWTDMn1, NcWTDMn2) was isolated from the brains of two fetuses by bioassays in mice, and subsequent propagation in cell culture. Dams of these two infected fetuses had antibodies to N. caninum by Neospora agglutination test at 1:100 serum dilution. DNA obtained from culture-derived N. caninum tachyzoites of the two isolates with Nc5 PCR confirmed diagnosis. Results prove congenital transmission of N. caninum in the white tailed deer for the first time. PMID:23566408

  4. 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.

  5. 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- ...

  6. Cliff Failure

    Cliff failure just south of San Gregorio Beach. Slide is 18.3 meters (60 ft) high and displaces approximately 6881 cubic meters (9,000 cubic yards) of material. Large boulders are 1 m (3 ft) across....

  7. 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√ā¬ģ Web Sites with More Information About Heart Failure For ...

  8. HVAC failures

    SciTech Connect

    Dillon, J.J.; Herro, H.M.

    1997-12-01

    HVAC (heating, ventilating, and air conditioning) failures occur mainly in chillers, service water systems, cooling towers, evaporative condensers, chilled-water systems, hot-water heating systems and steam boilers. Failures are caused by a variety of mechanisms including oxygen corrosion, tuberculation, dealloying, erosion, underdeposit attack, stress corrosion, corrosion fatigue, acid wastage, manufacturing defects, improper chemical treatment, and galvanic cells.Attack mechanisms are described and appropriate case histories given with specific emphasis on heating, ventilating and air conditioning systems.

  9. 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.

  10. Guidewall demolition at Bonneville Dam

    SciTech Connect

    Marks, R.S.

    1997-05-01

    Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers. The project involved drill and shoot, alluvial gravel and rock excavation, dredging, rock support, structural concrete, and assorted demolitions. A large portion of the demolition work was the removal of the existing guidewall to allow barge traffic access to the new lock. Guidewall Demolition was completed using drill and shoot techniques and dredging the debris from the channel. This work involved unique challenges and innovative solutions to produce a successful result.

  11. 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.

  12. 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 √ó 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.

  13. Numerical analysis of earthquake response of an ultra-high earth-rockfill dam

    NASA Astrophysics Data System (ADS)

    Dong, W. X.; Xu, W. J.; Yu, Y. Z.; Lv, H.

    2013-05-01

    Failure of high earth dams under earthquake may cause disastrous economic damage and loss of lives. It is necessary to conduct seismic safety assessment, and numerical analysis is an effective way. Solid-fluid interaction has a significant influence on the dynamic responses of geotechnical materials, which should be considered in the seismic analysis of earth dams. The initial stress field needed for dynamic computation is often obtained from postulation, without considering the effects of early construction and reservoir impounding. In this study, coupled static analyses are conducted to simulate the construction and impounding of an ultra-high earth rockfill dam in China. Then based on the initial static stress field, dynamic response of the dam is studied with fully coupled nonlinear method. Results show that excess pore water pressure accumulates gradually with earthquake and the maximum value occurs at the bottom of core. Acceleration amplification reaches the maximum at the crest as a result of whiplash effect. Horizontal and vertical permanent displacements both reach the maximum values at the dam crest.

  14. 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.

  15. States report on model dam safety program

    SciTech Connect

    Spragens, L. )

    1992-10-01

    The Association of State Dam Safety Officials developed a Model State Dam Safety Program in 1986 to serve as a guide for state officials initiating or improving dam safety programs. The program outlines the key components of an effective dam safety program and includes information on legislation and regulations, the permitting process, inspection, enforcement, emergency action planning, program staffing and training, and education. In 1990, ASDSO added a chapter to the program material, emphasizing the development of a program and budget, and how to present that program and budget to state legislatures. ASDSO plans to update materials for the entire Model State Dam Safety Program for the first time in 1993. The updated program materials will include recommendations from an Interagency Committee on Dam Safety (ICODS) subcommittee looking at issues involved with offering standard guidelines on emergency action planning procedures to state and federal officials. ASDSO will participate on that subcommittee. A number of states have used the Model State Dam Safety Program to enhance their own programs and to develop new or revised state regulations. Alabama, Arkansas, Colorado, North Carolina, and Utah are among states that have benefited, accorded to recent testimonials.

  16. Dams on the Mekong: Cumulative sediment starvation

    NASA Astrophysics Data System (ADS)

    Kondolf, G. M.; Rubin, Z. K.; Minear, J. T.

    2014-06-01

    The Mekong River, largely undeveloped prior to 1990, is undergoing rapid dam construction. Seven dams are under construction on the mainstem in China and 133 proposed for the Lower Mekong River and tributaries. We delineated nine distinct geomorphic regions, for which we estimated sediment yields based on geomorphic characteristics, tectonic history, and the limited sediment transport data available. We then applied the 3W model to calculate cumulative sediment trapping by these dams, accounting for changing trap efficiency over time and multiple dams on a single river system. Under a "definite future" scenario of 38 dams (built or under construction), cumulative sediment reduction to the Delta would be 51%. Under full build-out of all planned dams, cumulative sediment trapping will be 96%. That is, once in-channel stored sediment is exhausted, only 4% of the predam sediment load would be expected to reach the Delta. This scenario would have profound consequences on productivity of the river and persistence of the Delta landform itself, and suggests that strategies to pass sediment through/around dams should be explored to prevent the consequences of downstream sediment starvation.

  17. The role of dams in development.

    PubMed

    Altinbilek, Dońüan

    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

  18. Sustainability of dams-an evaluation approach

    NASA Astrophysics Data System (ADS)

    Petersson, E.

    2003-04-01

    Situated in the stream bed of a river, dams and reservoirs interrupt the natural hydrological cycle. They are very sensitive to all kinds of changes in the catchment, among others global impacts on land use, climate, settlement structures or living standards. Vice versa dams strongly affect the spatially distributed, complex system of ecology, economy and society in the catchment both up- and downstream of the reservoir. The occurrence of negative impacts due to large dams led to serious conflicts about future dams. Nevertheless, water shortages due to climatic conditions and their changes, that are faced by enormous water and energy demands due to rising living standards of a growing world population, seem to require further dam construction, even if both supply and demand management are optimised. Although environmental impact assessments are compulsory for dams financed by any of the international funding agencies, it has to be assumed that the projects lack sustainability. Starting from an inventory of today's environmental impact assessments as an integral part of a feasibility study the presentation will identify their inadequacies with regard to the sustainability of dams. To improve the sustainability of future dams and avoid the mistakes of the past, the planning procedures for dams have to be adapted. The highly complex and dynamical system of interrelated physical and non-physical processes, that involves many different groups of stakeholders, constitutes the need for a model-oriented decision support system. In line with the report of the World Commission of Dams an integrated analysis and structure of the complex interrelations between dams, ecology, economy and society will be presented. Thus the system, that a respective tool will be based on, is analysed. Furthermore an outlook will be given on the needs of the potential users of a DSS and how it has to be embedded in the overall planning process. The limits of computer-based decision-support in the very specific context of dam construction will be identified. Special focus will be on the constraints arising from the need to jointly evaluate qualitative and quantitative aspects and the methodological potential of multi-criteria evaluation in this respect.

  19. 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.

  20. 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

  1. 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

  2. 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

  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. 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

  5. 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

  6. 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.

  7. 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...

  8. Earthquake-dammed lakes in New Zealand

    SciTech Connect

    Adams, J.

    1981-05-01

    Eleven small lakes were formed by landslides caused by the 1929 Buller earthquake; four others were formed by other historic earthquakes in New Zealand. At least nine other New Zealand lakes are also dammed by landslides and were probably formed by prehistoric earthquakes. When recognized by morphology, synchronous age, and areal distribution, earthquake-dammed lakes could provide an estimate of paleoseismicity for the past few hundred or thousand years.

  9. Global phosphorus retention by river damming

    PubMed Central

    Maavara, Taylor; Parsons, Christopher T.; Ridenour, Christine; Stojanovic, Severin; D√ľrr, 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‚ąí1, 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

  10. Global phosphorus retention by river damming.

    PubMed

    Maavara, Taylor; Parsons, Christopher T; Ridenour, Christine; Stojanovic, Severin; D√ľrr, 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

  11. Distributional Impacts of Large Dams in China

    NASA Astrophysics Data System (ADS)

    Bao, X.

    2010-12-01

    Dams on a river are believed to have heterogeneous impacts to the upstream, local and downstream areas. Generally, irrigation dams will bring benefits to the downstream by facilitating more irrigation, while it will bring negative impacts to upstream due to inundation or no impact to local area as a combination result of population dislocation and economic benefits. This paper checked the impacts of large dams (above 100 meters) on the upstream, downstream and local area, using 2000-2008 county level data in China. Robust heterogeneous impacts of different categories of dams (mainly dams serving for irrigation, hydropower, or other purposes) were found on different areas, using IV regression approaches. Dams higher than 100 meters are significantly and heterogeneously impacting agricultural production, urban employment and rural per capita income. Its beneficial impact on agriculture production is significant for downstream especially in continuous drought years. But its impacts on social welfare indicators, such as primary school enrollment and hospital beds, are not heterogeneously different across regions.

  12. Uplift investigations at Tillery Dam

    SciTech Connect

    Bandy, M.; Booth, P.; Auger, S.

    1995-12-31

    Tillery Dam is located approximately 50 miles east of Charlotte, North Carolina, on the Pee Dee River. Construction of the project was completed in 1928 and, beginning from the east side of the project, it consists of a powerhouse and intake section and east nonoverflow section totaling 618 feet long with a maximum height of 98.5 feet above the rock foundation. The concrete spillway is 758 feet long with 18 34-foot-wide by 24-foot-high tainter gates mounted on a 62-foot-high ogee section with a concrete stilling basin. The west nonoverflow section is 176 feet long. The west end of the project consists of a 1,200-foot-long earth embankment with a maximum height of 77 feet above the cut-off trench that extends to rock. Carolina Power & Light (CP&L) owns the project and operates the facility in accordance with its license issued by the Federal Energy Regulatory Commission (FERC). In 1990, during the review of a safety inspection report submitted by CP&L and its consultant, FERC made several comments concerning the concrete gravity and embankment structures.

  13. Direct bond brackets: cotton roll versus rubber dam isolation.

    PubMed

    Heringer, M; Almeida, M A; Miguel, J A

    1993-01-01

    Forty-four brackets were bonded "in vivo" using cotton roll and rubber dam isolation. Maxillary and mandibular premolars, to be extracted for orthodontic reasons, were used in this study. After bonding, the teeth were retained in the mouth for at least 30 days. They were extracted using surgical elevators. After extraction, the teeth were secured in plastic rings using gypsum and kept in water for 7 days until debonding. A Universal Instron Machine was used to produce a shear force at a speed of 0.1 cm/min until each bracket was removed. No statistically significant differences for debonding strength were observed between the two types of isolation, nor between the buccal and palatal surfaces of the teeth. One hundred percent of the failures occurred at the bracket/composite interface. PMID:8214793

  14. 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.

  15. 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 ...

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

    PubMed

    Feketeov√°, Zuzana; Hulejov√° Sl√°dkovińćov√°, Veronika; Mangov√°, Barbara; ҆imkovic, 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. The Effects of Dams on Downstream Channel Characteristics in Pennsylvania and Maryland: Assessing the Potential Consequences of Dam Removal

    NASA Astrophysics Data System (ADS)

    Skalak, K. J.; Pizzuto, J. E.; Jenkins, P.

    2003-12-01

    The potential downstream effects of dam removal were assessed on fifteen sites of varying dam size and characteristics in Pennsylvania and Maryland. The dams ranged in size from a 30 cm high fish weir to a water supply dam 57 m high. Stream order ranged from 1 to 4. The dams are located in watersheds with varying degrees of human disturbance and urbanization. The dams are also operated differently, with significant consequences for hydraulic residence time and downstream flow variability. Most streams were alluvial, but 6 of the reaches were clearly bedrock channels. We hypothesize that the channel upstream, which is unaffected by the dam, will provide an accurate model for the channel downstream of the dam long after dam removal. Therefore, reaches upstream and downstream of the dam were compared to determine the effects of the dam as well as the condition of the stream that will ultimately develop decades after dam removal. Surprisingly, the dams had no consistent influence on channel morphology. However, the percentage of sand is significantly lower downstream than upstream: the mean % sand downstream is 11.47%, while the mean % sand upstream is 21.39%. The coarser fractions of the bed, as represented by the 84th percentile grain diameter, are unaffected by the presence of the dam. These results imply that decades after dam removal, the percentage of sand on the bed will increase, but the coarse fraction of the bed will remain relatively unchanged.

  18. Black-Tailed Prairie Dog

    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...

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

    USGS Publications Warehouse

    Bedrosian, P.A.; Burton, B.L.; Powers, M.H.; Minsley, B.J.; Phillips, J.D.; Hunter, L.E.

    2012-01-01

    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.

  1. 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

    ... preferred alternative in both the Draft EIS and Final EIS. Alternative C--Permanent Modification of Dam... gap closure barriers between segments of floodwalls. An additional modification to Alternative B is... was selected over Alternative C--Permanent Modification of Dam Structures: All Concrete...

  2. Failure Assessment

    NASA Technical Reports Server (NTRS)

    Lutz, Robyn; Nikora, Allen

    2005-01-01

    Three questions to which software developers want accurate, precise answers are "How can the software system fail?", "mat bad things will happen if the software fails?t', and "How many failures will the software experience?". Numerous techniques have been devised to answer these questions; three of the best known are: 1) Software Fault Tree Analysis (SFTA) 2) Software Failure Modes, Effects, and Criticality Analysis (SFMECA 3) Software Fault/Failure Modeling. SFTA and SFMECA have been successfully used to analyze the flight software for a number of robotic planetary exploration missions, including Galileo, Cassini, and Deep Space 1. Given the increasing interest in reusing software components from mission to mission, one of us has developed techniques for reusing the corresponding portions of the SFTA and SFMECA, reducing the effort required to conduct these analyses. SFTA has also been shown to be effective in analyzing the security aspects of software systems; intrusion mechanisms and effects can easily be modeled using these techniques. The Bi- Directional Safety Analysis (BDSA) method combines a forward search (similar to SFMECA) from potential failure modes to their effects, with a backward search (similar to SFTA) from feasible hazards to the contributing causes of each hazard. BDSA offers an efficient way to identify latent failures. Recent work has extended BDSA to product-line applications such as flight-instrumentation displays and developed tool support for the reuse of the failure-analysis artifacts within a product line. BDSA has also been streamlined to support those projects having tight cost and/or schedule constraints for their failure analysis efforts. We discuss lessons learned from practice, describe available tools, and identi@ some future directions for the topic. A substantial amount of research has been devoted to estimating the number of failures that a software system will experience during test and operations, as well as the number of faults that have been inserted into that system during its development. One of us has found that the amount of structural change to a system during its development is strongly related to the number of faults inserted into it. Using techniques requiring no additional effort on the part of the development organization, the required measurements of structural evolution can be easily obtained from a development effort's configuration management system and readily transformed into an estimate of fault content. So far, structure-fault relationships have been identified for source code; current work seeks to examine artifacts available earlier in the lifecycle to determine if similar relationships between structure and fault content can be found. In particular, relationships between requirements change requests and the number of faults inserted into the implemented system would provide a significant improvement in our ability to control software quality during the early development phases.

  3. 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.

  4. Migration of arsenic from old tailings ponds-A case study on the King Edward Mine, Cornwall, UK

    SciTech Connect

    Beeston, Michael Philip Tuen van Elteren, Johannes; Slejkovec, Zdenka; Glass, Hylke Jan

    2008-09-15

    A methodology is presented to study the physico-chemical processes in old tailings ponds using an array of analytical-physical chemistry approaches. A case study was conducted on the sorption/desorption behaviour of arsenic in tailings pond 2406, at the King Edward Mine (KEM) in Cornwall, UK. The tailings pond was in operation from approximately 1907 to 1921. The methodology involves two principal stages: (1) sequential extraction followed by subsequent arsenic species determination to characterise the material with regards to the association of arsenic with soil phases and identification of As (III/V) in the easily accessible soil phase; (2) batch contacting/equilibrating the tailings pond material with As(III/V), followed by a similar procedure as in stage 1 to establish the material's As(III/V) phase distribution kinetics/thermodynamics. By extrapolating the data from present day samples we infer past and future elemental mobility. From this study it is concluded that adsorption and desorption from tailings material is a rapid process for the most unstable soil phases (non-specific and specific) and a slow process for the more stable phases (poorly crystalline and well crystalline). The hypothetical application of this conclusion to the tailings from dam 2406 is that, during the initial phases of the dam's creation (ca. 100 years ago), when arsenic was both in solution and bound to mineralogical components, arsenic must have dispersed into the environment as a result of slow As(V) adsorption/phase distribution processes. Aging of the tailings material sees the movement of the arsenic to the more stable soil phases, producing a situation that is seen at present day.

  5. Wavelet analysis of the hydrologic effects of Glen Canyon Dam on the Colorado River at Lees Ferry, Arizona

    NASA Astrophysics Data System (ADS)

    White, M. A.; Schmidt, J. C.; Topping, D. J.

    2003-12-01

    Continuous wavelet transformation is a powerful analytical tool with which to analyze the hydrologic effects of dam construction and operation on river systems, an issue of great managerial, political, and social interest in the western United States. Using continuous records of instantaneous discharge from the Lees Ferry gaging station and records of daily mean discharge from upstream tributaries, we conducted a continuous wavelet transformation (CWT) analysis of the pre- and post-dam hydrologic structure of the Colorado River in Grand Canyon, downstream from Glen Canyon Dam. CWT of mean daily discharge provided a highly compressed and integrative picture of the near-total elimination of pronounced annual and sub-annual wavelet features after dam construction. Events such as droughts, managed floods, and uncontrollable snowmelt-driven discharge were also visible. The continuous record, interpolated to consistent hourly intervals, revealed a much finer scale image of river conditions. Prior to dam construction, the CWT showed the influence of warm season peak discharge periods, discharge driven by the monsoon and dissipating tropical storms, and annual droughts. In the post-dam period, strong wavelet signals related to diurnal power generation, weekly shutdowns in power generation, shifts in daily discharge management, and the 1996 experimental flood were dominant. The CWT approach appears to represent well-known features of dam operation without generation of spurious results. Thus, CWT, with quantitative statistical significance tests, should be a promising tool for assessing (1) dam operation in less well-studied regions and (2) real-time success or failure of management attempts to reconstruct desired flow characteristics.

  6. 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.

  7. 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.

  8. 14 CFR 29.1565 - Tail rotor.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Tail rotor. 29.1565 Section 29.1565 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS....1565 Tail rotor. Each tail rotor must be marked so that its disc is conspicuous under normal...

  9. 14 CFR 27.1565 - Tail rotor.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Tail rotor. 27.1565 Section 27.1565 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Tail rotor. Each tail rotor must be marked so that its disc is conspicuous under normal daylight...

  10. 14 CFR 29.1565 - Tail rotor.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tail rotor. 29.1565 Section 29.1565 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS....1565 Tail rotor. Each tail rotor must be marked so that its disc is conspicuous under normal...

  11. 14 CFR 27.1565 - Tail rotor.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tail rotor. 27.1565 Section 27.1565 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Tail rotor. Each tail rotor must be marked so that its disc is conspicuous under normal daylight...

  12. 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

  13. Differential gene expression between the embryonic tail bud and regenerating larval tail in Xenopus laevis.

    PubMed

    Sugiura, Takuji; Taniguchi, Yuka; Tazaki, Akira; Ueno, Naoto; Watanabe, Kenji; Mochii, Makoto

    2004-02-01

    The regeneration of the amputated tail of Xenopus laevis larvae is an excellent model system for regeneration research. The wound left by the amputated tail is covered with epidermis within 24 h. Then, the cell number increases near the amputation plane at the notochord, spinal cord and muscle regions. An apparently complete tail with notochord, muscle and spinal cord is regenerated within two weeks. To reveal whether the molecular mechanism underlying the tail regeneration is the same as that in embryonic tail development, the gene expression patterns of the embryonic tail bud and the regenerating tail were compared by in situ hybridization and reverse transcription-polymerase chain reaction. Most genes analyzed were expressed at similar levels in both tissues, whereas two bone morphogenetic protein (BMP)-antagonists, chordin and noggin, were detected only in the embryonic tail bud. The regenerating tail also lacked expression of Xshh in the floor plate and expression of Xdelta-1 in the spinal cord and presomitic mesoderm. These results show that there are some differences in gene expression between the two processes. Furthermore, when the tail of Xenopus larvae is amputated, the regenerating tail has a gene expression pattern similar to the distal portion of the larval tail rather than the embryonic tail bud, suggesting that the cut larval tail does not make a new embryonic tail bud, but rather a new larval tail tip for regeneration. PMID:15008858

  14. 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.

  15. Methodology for the calculation of annualized incremental risks in systems of dams.

    PubMed

    Serrano-Lombillo, Armando; Escuder-Bueno, Ignacio; de Membrillera-OrtuŮo, Manuel G; Altarejos-GarcŪa, Luis

    2011-06-01

    In the past few years, the field of dam safety has approached risk informed methodologies throughout the world and several methodologies and programs are appearing to aid in the systematization of the calculations. The most common way of implementing these calculations is through the use of event trees, computing event probabilities, and incremental consequences. This methodology is flexible enough for several situations, but its generalization to the case of systems of several dams is complex and its implementation in a completely general calculation methodology presents some problems. Retaining the event tree framework, a new methodology is proposed to calculate incremental risks. The main advantage of this proposed methodology is the ease with which it can be applied to systems of several dams: with a single risk model that describes the complete system and with a single calculation the incremental risks of the system can be obtained, being able to allocate the risk of each dam and of each failure mode. The article shows how both methodologies are equivalent and also applies them to a case study. PMID:21175718

  16. Social Impacts of Brazil's TucuruŪ Dam.

    PubMed

    Fearnside

    1999-11-01

    / The TucuruŪ Dam, which blocked the Tocantins River in 1984 in Brazil's eastern Amazonian state of ParŠ, is a continuing source of controversy. Most benefits of the power go to aluminum smelting companies, where only a tiny amount of employment is generated. Often presented by authorities as a model for hydroelectric development because of the substantial power that it produces, the project's social and environmental impacts are also substantial. Examination of TucuruŪ reveals a systematic overestimation of benefits and underestimation of impacts as presented by authorities. TucuruŪ offers many as-yet unlearned lessons for hydroelectric development in Amazonia.KEY WORDS: TucuruŪ Dam; Amazonia; Hydroelectric dams; Brazil; Reservoirs; Mercuryhttp://link.springer-ny.com/link/service/journals/00267/bibs/24n4p483.html

  17. Uranium mill tailings quarterly report, January-March 1982

    SciTech Connect

    Latkovich, J.M.

    1982-05-01

    Progress is reported on: radon barrier systems for uranium mill tailings; liner evaluation for uranium mill tailings; revegetation/rock cover for stabilization of inactive U-tailings sites; and application of long-term chemical biobarriers for uranium tailings.

  18. Analysis of deformations of large earth dams

    NASA Astrophysics Data System (ADS)

    Szostak-Chrzanowski, Anna; Massiťra, 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.

  19. Tidal Tails of Globular Clusters

    NASA Astrophysics Data System (ADS)

    Yim, Ki-Jeong; Lee, Hyung Mok

    2002-06-01

    We present N-body simulations of globular clusters including gravitational field of the Galaxy, in order to study effects of tidal field systematically on the shape of outer parts of globular clusters using NBODY6. The Galaxy is assumed to be composed of central bulge and outer halo. We investigate the cluster of multi-mass models with a power-law initial mass function (IMF) starting with different initial masses, initial number of particles, different slopes of the IMF and different orbits of the cluster. We have examined the general evolution of the clusters, the shape of outer parts of the clusters, density profiles and the direction of tidal tails. The density profiles appear to become somewhat shallower just outside the tidal boundary consistent with some observed data. The position angle of the tidal tail depends on the location in the Galaxy as well as the direction of the motion of clusters. We found that the clusters become more elongated at the apogalacticon than at the perigalacticon. The tidal tails may be used to trace the orbital paths of globular clusters.

  20. Instanton calculus of Lifshitz tails

    NASA Astrophysics Data System (ADS)

    Yaida, Sho

    2016-02-01

    Some degree of quenched disorder is present in nearly all solids, and can have a marked impact on their macroscopic properties. A manifestation of this effect is the Lifshitz tail of localized states that then gets attached to the energy spectrum, resulting in the nonzero density of states in the band gap. We present here a systematic approach for deriving the asymptotic behavior of the density of states and of the typical shape of the disorder potentials in the Lifshitz tail. The analysis is carried out first for the well-controlled case of noninteracting particles moving in a Gaussian random potential and then for a broad class of disordered scale-invariant models‚ÄĒpertinent to a variety of systems ranging from semiconductors to semimetals to quantum critical systems. For relevant Gaussian disorder, we obtain the general expression for the density of states deep in the tail, with the rate of exponential suppression governed by the dynamical exponent and spatial dimensions. For marginally relevant disorder, however, we would expect a power-law scaling. We discuss the implications of these results for understanding conduction in disordered materials.

  1. 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.

  2. Comet Tails of Type 2

    NASA Technical Reports Server (NTRS)

    Probstein, R. F.

    1972-01-01

    A summary is presented of a theory for the head and tail regions of Type 2 (dust) comets, wherein dust particles having a wide distribution of sizes are assumed to be released from the comet nucleus in an essentially continuous manner in time during the period of distinctive cometary phenomena. The dust particles are assumed to be accelerated radially outward from the nucleus as a result of a drag interaction with the expanding gas in the comet head. In the tail region the only significant forces assumed to act on the dust particles are solar gravity and the force of solar radiation pressure. It is shown how results describing the surface density in the tail are obtained and how by matching calculated distributions with measured ones it is possible to determine the dust and head-gas emission rates as a function of time, the distribution of dust particle sizes, and the emission velocity from the inner head region as a function of particle size and time. The results of matching calculated density distributions with light intensity measurements from Comet Arend-Roland 1956h are summarized.

  3. 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

  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. Method to quantify tail vein injection technique in small animals.

    PubMed

    Groman, Ernest V; Reinhardt, Christopher P

    2004-01-01

    Injection errors, which are often not readily recognized, can greatly impact the outcome of a pre-clinical research study. As a result, unrecognized misadministration of test compounds can render a high cost to the biomedical community. In this report, we propose six criteria for a reagent designed to assess tail vein injection technique in small animals and suggest a reagent, colloidal gold labeled with the stable isotope 197Au, that satisfies these criteria, thereby describing and validating for the first time a method to quantify technical compliance in tail vein injections. In an application of this reagent, we show the degree of variation experienced by technologists performing tail vein injection procedures in mice. In this study, mice were manually restrained and received an injection in the tail vein. One hour after injection, the mice were euthanized, various organs including the tail (the site of the injection) were collected, and their gold content was quantified by neutron activation. The three experienced animal technologists in the study were tested for tail vein injection proficiency in 30 mice. Prior to the study, the supervisor stated that a misinjection occurs when more than 10% of the intended volume remains in the tail. In light of this criterion, 12 of the 30 injections were misadministered: two with technologist 1, three with technologist 2, and seven with technologist 3. Although she was able to correctly rank the injection skills of the three technologists used in this experiment, i.e., technologist 1 and 2 more better skilled than technologist 3, the supervisor greatly underestimated the extent and degree of injection failures for the procedure. The results of the study illustrate the potential problems associated with the technical compliance with this common laboratory procedure and suggest that there is a need to validate injection methods and a need to monitor technical competence. Application of reagents similar to colloidal gold and the methods presented will facilitate the development of improved methods of teaching injection technique and monitoring technical quality in the laboratory setting. In Vivo Micro Computed Tomography of Subchondral Bone in the Rat After Intra-articular Administration of Monosodium Iodoacetate PMID:14984288

  6. Tailings Pond Characterization And Designing Through Geophysical Surveys In Dipping Sedimentary Formations

    NASA Astrophysics Data System (ADS)

    Muralidharan, D.; Andrade, R.; Anand, K.; Sathish, R.; Goud, K.

    2009-12-01

    Mining activities results into generation of disintegrated waste materials attaining increased mobilization status and requires a safe disposal mechanism through back filling process or secluded storage on surface with prevention of its interaction with environment cycle. The surface disposal of waste materials will become more critical in case of mined minerals having toxic or radioactive elements. In such cases, the surface disposal site is to be characterized for its sub-surface nature to understand its role in environmental impact due to the loading of waste materials. Near surface geophysics plays a major role in mapping the geophysical characters of the sub-surface formations in and around the disposal site and even to certain extent helps in designing of the storage structure. Integrated geophysical methods involving resistivity tomography, ground magnetic and shallow seismic studies were carried out over proposed tailings pond area of 0.3 sq. kms underlined by dipping sedimentary rocks consisting of ferruginous shales and dolomitic to siliceous limestone with varying thicknesses. The investigated site being located in tectonically disturbed area, geophysical investigations were carried out with number of profiles to visualize the sub-surface nature with clarity. The integration of results of twenty profiles of resistivity tomography with 2 m (shallow) and 10 m (moderate depth) electrode spacing’s enabled in preparing probable sub-surface geological section along the strike direction of the formation under the tailings pond with some geo-tectonic structure inferred to be a fault. Similarly, two resistivity tomography profiles perpendicular to the strike direction of the formations brought out the existence of buried basic intrusive body on the northern boundary of the proposed tailings pond. Two resistivity tomography profiles in criss-cross direction over the suspected fault zone confirmed fault existence on the north-eastern part of tailings pond. Thirty two magnetic profiles inside the tailings pond and surrounding areas on the southern part of the tailings pond enabled in identifying two parallel east-west intrusive bodies forming the impermeable boundary for the tailings pond. The shallow seismic refraction and the geophysical studies in and around the proposed tailings pond brought out the suitability of the site, even when the toxic elements percolates through the subsurface formations in to the groundwater system, the existence of dykes on either side of the proposed ponding area won’t allow the water to move across them thus by restricting the contamination within the tailings pond area. Similarly, the delineation of a fault zone within the tailings pond area helped in shifting the proposed dam axis of the pond to avoid leakage through the fault zone causing concern to environment pollution.

  7. 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.

  8. 76. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: DOWNSTREAM ...

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

    76. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: DOWNSTREAM ELEVATION, SHEET 3; OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  9. 74. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: PLAN, ...

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

    74. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: PLAN, SHEET 1, OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  10. 77. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: CROSS ...

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

    77. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: CROSS SECTIONS, SHEET 4; OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  11. 75. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: UPSTREAM ...

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

    75. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: UPSTREAM ELEVATION, SHEET 2; OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  12. 79. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: REINFORCEMENT, ...

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

    79. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: REINFORCEMENT, SHEET 6; OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  13. 78. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLEARCHED TYPE: DIMENSIONS, ...

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

    78. PALMDALE WATER COMPANY, LITTLEROCK DAM, EASTWOOD MULTIPLE-ARCHED TYPE: DIMENSIONS, SECTION THROUGH ARCH RING, SHEET 5; OCTOBER 2, 1919. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  14. 4. AERIAL VIEW OF DAM SITE SHOWING OUTLET WORKS AND ...

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

    4. AERIAL VIEW OF DAM SITE SHOWING OUTLET WORKS AND DIVERSION CHANNEL IN FOREGROUND.... Volume XVIII, No. 9, March 5, 1940. - Prado Dam, Santa Ana River near junction of State Highways 71 & 91, Corona, Riverside County, CA

  15. 15. AERIAL PHOTOGRAPH OF DAM SITE SHOWING SPILLWAY OGEE SECTION ...

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

    15. AERIAL PHOTOGRAPH OF DAM SITE SHOWING SPILLWAY OGEE SECTION AND SPILLWAY APRON EXCAVATION IN FOREGROUND.... Volume XVIII, No. 10, January 18, 1940. - Prado Dam, Spillway, Santa Ana River near junction of State Highways 71 & 91, Corona, Riverside County, CA

  16. 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

  17. 15. DETAIL FROM NORTH END OF DAM, SHOWING TOP OF ...

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

    15. DETAIL FROM NORTH END OF DAM, SHOWING TOP OF NORTHERNMOST BUTTRESS, END OF CONCRETE WALK ATOP NORTH EMBANKMENT, AND THE ROCK CREEK RESERVOIR BEYOND. - Rock Creek Dam, East end of Rock Creek Road, Auburn, Placer County, CA

  18. 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

  19. JOHN HOLLIS BANKHEAD LOCK & DAM IN TUSCALOOSA COUNTY, BIG ...

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

    JOHN HOLLIS BANKHEAD LOCK & DAM IN TUSCALOOSA COUNTY, BIG INDIAN CREEK PUBLIC USE AREA IN FOREGROUND. - John Hollis Bankhead Lock & Dam, On Warrior River below Port Birmingham, Kellerman, Tuscaloosa County, AL

  20. 1. VIEW SHOWING CONTRACTOR'S CAMP AND BARTLETT DAM IN THE ...

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

    1. VIEW SHOWING CONTRACTOR'S CAMP AND BARTLETT DAM IN THE DISTANCE. THE CONTRACTOR'S MESS HALL, COMMISSARY, RECREATIONAL HALL, DORMITORIES, CAMP HOSPITAL, AND WORKMEN'S COTTAGES ARE ALSO SHOWN. February 20, 1939 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

  1. 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

  2. 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

  3. 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

  4. 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

  5. 40. Reservoir behind Pleasant Dam, looking downstream, spillway is at ...

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

    40. Reservoir behind Pleasant Dam, looking downstream, spillway is at right. Photographer unknown, c. late 1920s. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  6. 70. Downstream view of Waddell Dam spillway and taintor gates. ...

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

    70. Downstream view of Waddell Dam spillway and taintor gates. Photographer Mark Durben. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  7. 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

  8. 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

  9. 50. Upstream face of Humbug Creek Diversion Dam showing sluice ...

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

    50. Upstream face of Humbug Creek Diversion Dam showing sluice opening. Photographer James Eastwood, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  10. 49. Downstream face of Humbug Creek Diversion Dam with sluice ...

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

    49. Downstream face of Humbug Creek Diversion Dam with sluice opening at center. Photographer James Eastwood, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  11. 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

  12. 54. Downstream face of Agua Fria project's diversion dam showing ...

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

    54. Downstream face of Agua Fria project's diversion dam showing initial masonry construction and poured concrete capping. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  13. 27. Evening view of downstream face of Pleasant Dam under ...

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

    27. Evening view of downstream face of Pleasant Dam under construction. Part of construction camp housing is visible in foreground. Photographer unknown, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  14. 39. Pleasant Dam from east abutment with spillway visible at ...

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

    39. Pleasant Dam from east abutment with spillway visible at center. Photographer unknown, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  15. 55. Downstream face of diversion dam looking northwest. Photographer Mark ...

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

    55. Downstream face of diversion dam looking northwest. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  16. 60. Waddell Dam in relation and spillway tailrace. Photographer Mark ...

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

    60. Waddell Dam in relation and spillway tailrace. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  17. 57. Downstream side of left section of diversion dam. Photographer ...

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

    57. Downstream side of left section of diversion dam. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  18. 56. Upstream face of diversion dam looking east. Headgates are ...

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

    56. Upstream face of diversion dam looking east. Headgates are partially visible at far left. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  19. 5. AVALON DAM GATE KEEPER'S COMPLEX: HOUSE (LEFT), WAREHOUSE ...

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

    5. AVALON DAM - GATE KEEPER'S COMPLEX: HOUSE (LEFT), WAREHOUSE (RIGHT), AND CCC LANDSCAPING (FOREGROUND). VIEW TO SOUTHEAST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  20. 6. AVALON DAM GATE KEEPER'S COMPLEX: GARAGE AND WAREHOUSE ...

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

    6. AVALON DAM - GATE KEEPER'S COMPLEX: GARAGE AND WAREHOUSE (LEFT), HOUSE (RIGHT), AND CCC LANDSCAPING (FOREGROUND). VIEW TO NORTH - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  1. 1. AVALON DAM GENERAL VIEW OF RESERVOIR SHOWING PROXIMITY ...

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

    1. AVALON DAM - GENERAL VIEW OF RESERVOIR SHOWING PROXIMITY OF OUTLET WORKS, SUSPENSION BRIDGE, AND GATEKEEPER'S COMPLEX. VIEW TO NORTH - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  2. 11. AVALON DAM GATE KEEPER'S COMPLEX: PUMPHOUSE AND LIFT ...

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

    11. AVALON DAM - GATE KEEPER'S COMPLEX: PUMPHOUSE AND LIFT FOR HOUSE WATER SUPPLY. VIEW TO EAST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 65. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    65. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: UPSTREAM ELEVATION, SHEET 3; APRIL, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  14. 1. CONTEXTUAL VIEW OF LITTLE FALLS DAM POWERPLANT AND NORTHWEST ...

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

    1. CONTEXTUAL VIEW OF LITTLE FALLS DAM POWERPLANT AND NORTHWEST END OF LITTLE FALLS TIE LINE. LOOKING WEST - Little Falls Tie Line Towers, Near Little Dam Falls on Spokane River, Wellpinit, Stevens County, WA

  15. 69. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    69. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: REINFORCEMENT SHEET, SHEET 5; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  16. 80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED ...

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

    80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED SHEET 5; SEPTEMBER, 1922. Palmdale Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  17. PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ARCH ...

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

    PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ARCH RING, AMENDED SHEET 6; SEPTEMBER, 1922. Palmdale Water District files - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  18. 64. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    64. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: PLAN VIEW, SHEET 2; APRIL, 1918. Palmdale Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  19. 66. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    66. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: DIMENSION SHEET, SECTION THROUGH CROWN, SHEET 6, APRIL, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  20. 67. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

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

    67. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: OUTLET GATES, CROWN SECTION, UPSTREAM ELEVATION AND DOWNSTREAM ELEVATION SHEET, SHEET 7; APRIL, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  1. 81. PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ...

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

    81. PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ARCH RING, AMENDED SHEET 6; SEPTEMBER, 1922. Palmdale Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  2. 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

  3. 5. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE ...

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

    5. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE NO. 1, AND SERVICE BRIDGE, LOOKING SOUTHEAST (DOWNSTREAM) - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

  4. 4. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE ...

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

    4. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE NO. 1 SERVICE BRIDGE, AND LOCOMOTIVE CRANE, LOOKING NORTHEAST (UPSTREAM) - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

  5. 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

  6. 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

  7. 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

  8. 138. MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; SPILLWAY GATES ...

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

    138. MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; SPILLWAY GATES AND IRRIGATION FALLS, SOUTHEAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  9. 1. DIVERSION GATE AT SPILLWAY, NORTH CANAL DAM (DIVERSION GATE ...

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

    1. DIVERSION GATE AT SPILLWAY, NORTH CANAL DAM (DIVERSION GATE FEEDING PIPE AT LOWER RIGHT), VIEW TO SOUTHWEST. - North Canal Dam & Diversion Canals, Deschutes Reclamation & Irrigation Company Canal, Empire Boulevard vicinity, Bend, Deschutes County, OR

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 15. SOUTH SIDE OF DAM SHOWING BAFFLE PIERS AT FOOT ...

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

    15. SOUTH SIDE OF DAM SHOWING BAFFLE PIERS AT FOOT OF SPILLWAY TO LEFT AND PARTIAL VIEW OF BUTTRESSES AND SIDEWALKS TO RIGHT. - Pit 4 Diversion Dam, Pit River west of State Highway 89, Big Bend, Shasta County, CA

  1. 44. Credit TR. Dam No. 4 after 1936 flood from ...

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

    44. Credit TR. Dam No. 4 after 1936 flood from downstream showing break closed and installation of new concrete cap piece under way. Photo c. 1936. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  2. 42. Credit TR. Dam No. 4 after 1936 flood; break ...

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

    42. Credit TR. Dam No. 4 after 1936 flood; break as seen from upstream. Note original timber cribbing to left. Photo c. 1936. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  3. 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

  4. GENERAL AERIAL VIEW TO SOUTH OF ELWHA DAM AND POWERHOUSE ...

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

    GENERAL AERIAL VIEW TO SOUTH OF ELWHA DAM AND POWERHOUSE WITH NORTH END OF RESERVOIR. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Elwha Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

  5. GENERAL AERIAL VIEW OF LAKE ALDWELL AND ELWHA DAM AND ...

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

    GENERAL AERIAL VIEW OF LAKE ALDWELL AND ELWHA DAM AND POWERHOUSE, WITH STRAIT OF JUAN DE FUCA TO THE NORTH. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Elwha Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

  6. 1. UPSTREAM VIEW OF THE SOUTH CHANNEL DAM, LOOKING EAST. ...

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

    1. UPSTREAM VIEW OF THE SOUTH CHANNEL DAM, LOOKING EAST. - Washington Water Power Company Post Falls Power Plant, South Channel Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  7. 2. DOWNSTREAM VIEW OF THE SOUTH CHANNEL DAM, LOOKING WEST. ...

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

    2. DOWNSTREAM VIEW OF THE SOUTH CHANNEL DAM, LOOKING WEST. - Washington Water Power Company Post Falls Power Plant, South Channel Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  8. View of Lake Sabrina Dam and Lake Sabrina from east ...

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

    View of Lake Sabrina Dam and Lake Sabrina from east ridge showing spillway at photo center, view southwest - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  9. View of Lake Sabrina Dam showing the wooden planks along ...

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

    View of Lake Sabrina Dam showing the wooden planks along the upstream side face and the spillway at the right center of photo, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  10. View of upstream face of Lake Sabrina Dam showing redwood ...

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

    View of upstream face of Lake Sabrina Dam showing redwood planks and boulders in Lake Sabrina Basin, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  11. View of Lake Sabrina Dam upstream face from ridge showing ...

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

    View of Lake Sabrina Dam upstream face from ridge showing spillway at lower right of photo, view southwest - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

  12. 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

  13. 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

  14. 11. VIEW OF DAM ROLLER GATE IN RAISED POSITION, WITH ...

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

    11. VIEW OF DAM ROLLER GATE IN RAISED POSITION, WITH HEADHOUSE IN BACKGROUND AND BRIDGE IN LEFT FOREGROUND, LOOKING NORTHEAST - Upper Mississippi River 9-Foot Channel Project, Lock & Dam No. 3, Red Wing, Goodhue County, MN

  15. 10. VIEW OF DAM ROLLER GATE IN LOWERED POSITION, WITH ...

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

    10. VIEW OF DAM ROLLER GATE IN LOWERED POSITION, WITH HEADHOUSE IN BACKGROUND AND BRIDGE IN LEFT FOREGROUND, LOOKING NORTHEAST - Upper Mississippi River 9-Foot Channel Project, Lock & Dam No. 3, Red Wing, Goodhue County, MN

  16. 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

  17. 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

  18. 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

  19. 20. VIEW OF ENLOE DAM (APPARENTLY COMPLETED), PENSTOCK UNDER CONSTRUCTION ...

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

    20. VIEW OF ENLOE DAM (APPARENTLY COMPLETED), PENSTOCK UNDER CONSTRUCTION (LEFT, CENTER), AND THE ORIGINAL POWERHOUSE (RIGHT, CENTER). LOOKING NORTH - Enloe Dam, On Similkameen River, Oroville, Okanogan County, WA

  20. 9. DAM CONSTRUCTION PHOTO SHOWING STEEL SHEET PILING FOR OGEE ...

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

    9. DAM CONSTRUCTION PHOTO SHOWING STEEL SHEET PILING FOR OGEE SPILLWAY, LOOKING NORTH. August 1935 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 16, Upper Mississippi River, Muscatine, Muscatine County, IA

  1. 1. OVERALL VIEW OF UPSTREAM FACE OF DAM; SPILLWAY IN ...

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

    1. OVERALL VIEW OF UPSTREAM FACE OF DAM; SPILLWAY IN FOREGROUND, LOCK IN BACKGROUND ON NORTH RIVER BANK. VIEW TO NORTH. - Starved Rock Locks & Dam, Illinois Waterway River mile 231, Peru, La Salle County, IL

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 3. VIEW SOUTHEAST, WEST END OF DAM AT LEFT CENTER, ...

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

    3. VIEW SOUTHEAST, WEST END OF DAM AT LEFT CENTER, HEADGATE STRUCTURE AT CENTER - Dayville Mills Hydroelectric Facility, Dam, North side of Route 101, .5 mile west of Route 395, Killingly Center, Windham County, CT

  9. 1. VIEW NORTH, SOUTH FACE OF DAM AT RIGHT CENTER, ...

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

    1. VIEW NORTH, SOUTH FACE OF DAM AT RIGHT CENTER, HEADGATES AND CANAL AT LEFT - Dayville Mills Hydroelectric Facility, Dam, North side of Route 101, .5 mile west of Route 395, Killingly Center, Windham County, CT

  10. 2. VIEW EAST, WEST END OF DAM AT CENTER, HEADGATE ...

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

    2. VIEW EAST, WEST END OF DAM AT CENTER, HEADGATE OPERATING MECHANISMS AT LEFT - Dayville Mills Hydroelectric Facility, Dam, North side of Route 101, .5 mile west of Route 395, Killingly Center, Windham County, CT

  11. 22. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN ...

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

    22. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN DISTANCE; LOOKING EAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  12. 23. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN ...

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

    23. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN DISTANCE; LOOKING NORTHEAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  13. 9. VIEW OF DOWNSTREAM SIDE OF SPILLWAY AT DAM 320, ...

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

    9. VIEW OF DOWNSTREAM SIDE OF SPILLWAY AT DAM 320, SHOWING ORIGINAL FIELDSTONE WEIR WALL BENEATH CONCRETE BUTTRESSING, LOOKING SOUTHEAST - J. Clark Salyer National Wildlife Refuge, Dam 320, Along Lower Souris River, Kramer, Bottineau County, ND

  14. 6. VIEW SOUTHWEST ON SHELTON SIDE OF DAM AND SPILLWAY. ...

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

    6. VIEW SOUTHWEST ON SHELTON SIDE OF DAM AND SPILLWAY. SHELTON GATEHOUSE ON LEFT. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

  15. 139. MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; OUTLET SIDE ...

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

    139. MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; OUTLET SIDE OF SPILLWAY, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  16. 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

  17. DOWNSTREAM VIEW OF LOCK. CONTROL TOWER AT REAR. DAM GATE ...

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

    DOWNSTREAM VIEW OF LOCK. CONTROL TOWER AT REAR. DAM GATE STRUCTURE AT RIGHT. NOTE TRAFFIC LIGHT FOR SHIPPING. LOOKING SOUTH SOUTHWEST. - Illinois Waterway, Peoria Lock and Dam, 1071 Wesley Road, Creve Coeur, Tazewell County, IL

  18. Gene expression of DAM5 and DAM6 is suppressed by chilling temperatures and inversely correlated with bud break rate.

    PubMed

    Jiménez, S; Reighard, G L; Bielenberg, D G

    2010-05-01

    We previously identified a cluster of d ormancy-a ssociated M ADS-box transcription factors (DAM genes) in peach [Prunus persica (L.) Batsch] as potential candidates for control of the non-dormant phenotype observed in the evg mutant. Of these genes, DAM3, DAM5 and DAM6 were winter expressed, suggesting a role for these genes during endodormancy. We used peach cultivars with contrasting chilling requirements (CR) for bud break to observe the expression of DAM3, DAM5 and DAM6 in response to chilling accumulation in the field and controlled environments. Vegetative terminal and floral buds were sampled weekly from field grown 'Contender' (1050 h CR), 'Rubyprince' (850 h CR) and 'Springprince' (650 h CR) peach cultivars through winter 2008-2009. Flower and vegetative terminal bud break potential was evaluated at each sampling by forcing cuttings in a growth-permissive environment. We also measured vegetative terminal bud break and DAM gene expression in potted 'Contender' and 'Peen-To' (450 h CR) trees under controlled-environment cold exposure. DAM3, DAM5 and DAM6 are all suppressed by exposure to chilling temperatures in the field and in controlled conditions. Expression of DAM5 and DAM6 are higher in high chill cultivars prior to chilling accumulation and their expression level reaches a minimum in each cultivar coincident with acquisition of bud break competence. Expression levels of DAM5 and DAM6 in vegetative tips in controlled environment conditions were negatively correlated with the time required for bud break in forcing conditions. The expression patterns of DAM5 and DAM6 are consistent with a role as quantitative repressors of bud break. PMID:20143130

  19. Dams and transnational advocacy: Political opportunities in transnational collective action

    NASA Astrophysics Data System (ADS)

    Fu, Teng

    Possible arguments to explain the gradual decline in big dam development and its site transferring from developed to developing countries include technical, economic, and political factors. This study focuses on the political argument---the rise of transnational anti-dam advocacy and its impact on state policy-making. Under what conditions does transnational anti-dam advocacy matter? Under what conditions does transnational advocacy change state dam policies (delay, scale down, or cancel)? It examines the role of transnational anti-dam actors in big dam building in a comparative context in Asia. Applying the social movement theory of political opportunity structure (POS) and using the qualitative case-study method, the study provides both within-case and cross-case analyses. Within-case analysis is utilized to explain the changing dynamics of big dam building in China (Three Gorges Dam and proposed Nu/Salween River dam projects), and to a lesser extent, Sardar Sarovar Project in India and Nam Theun 2 Dam in Laos. Different domestic and international POS (DPOS and IPOS) impact the strategies and outcomes of anti-dam advocacies in these countries. The degree of openness of the POS directly affects the capacity of transnational efforts in influencing state dam policies. The degree of openness or closure is measured by specific laws, institutions, discourse, or elite allies (or the absence of these) for the participation of non-state actors on big dam issues at a particular moment. This degree of openness is relative, varying over time, across countries and regions. This study finds that the impact of transnational anti-dam activism is most effective when both DPOS and IPOS are relatively open. Transnational anti-dam advocacy is least effective in influencing state dam policies when both DPOS and IPOS are relatively closed. Under a relatively open DPOS and closed IPOS, transnational anti-dam advocacy is more likely to successfully change state dam policies and even facilitate the opening of relatively closed IPOS. In contrast, under a relatively closed DPOS and open IPOS, transnational anti-dam advocacy can hardly exist. Without the domestic anti-dam pressure from below, international anti-dam efforts from above are less likely to affect state dam policies or open up closed DPOS.

  20. "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

  1. 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

  2. 9. View across top of dam, looking west. The angle ...

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

    9. View across top of dam, looking west. The angle of the dam is evident. View also provides a close-up view of downstream side of an arch-ring - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  3. 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

  4. 1. AERIAL VIEW OF LOCK AND DAM, LOOKING EAST Photocopy ...

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

    1. AERIAL VIEW OF LOCK AND DAM, LOOKING EAST Photocopy of photograph, ca. 1980, courtesy of the U.S. Engineer Office, St. Louis, Missouri. Original print on file at Mississippi River Lock and Dam No. 24, Clarksville, Missouri - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 24, Clarksville, Pike County, MO

  5. 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.

  6. 60. AVALON DAM Photographic copy of historic photo, January ...

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

    60. AVALON DAM - Photographic copy of historic photo, January 28, 1907 (original print filed in Record Group 115, National Archives, Washington, D.C.) W.J.Lubken, photographer 'REINFORCED CONCRETE DIAPHRAGM, LOOKING WEST FROM EAST SIDE OF AVALON DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  7. 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 southwest. Note the trash racks at the entrance to the penstocks. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  8. LOOKING DOWNSTREAM FROM KACHESS DAM CREST, 1910 RIVER CUTOFF CHANNEL ...

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

    LOOKING DOWNSTREAM FROM KACHESS DAM CREST, 1910 RIVER CUTOFF CHANNEL WITH CRIB STRUCTURE IN CENTER. BRIDGE FOOTING CRIB STRUCTURE AT RIGHT (Upstream face of Kachess Dam in foreground) - Kachess Dam, Cutoff Channel and Crib Structures, Kachess River, 1.5 miles north of Interstate 90, Easton, Kittitas County, WA

  9. 2. Upstream face of Rock Creek Diversion Dam, looking east ...

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

    2. Upstream face of Rock Creek Diversion Dam, looking east (Canal slide gates to left, Rock Creek diversion gate to right in raised position) - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  10. 4. Downstream face of Rock Creek Diversion Dam, looking west ...

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

    4. Downstream face of Rock Creek Diversion Dam, looking west (Irrigation District canal to right, creek gate and weir to left) - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  11. 1. Upstream face of Rock Creek Diversion Dam, looking east ...

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

    1. Upstream face of Rock Creek Diversion Dam, looking east (Overflow weir right, diversion section into Irrigation District Canal to left) - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  12. 6. Downstream face of Rock Creek Diversion Dam, looking west ...

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

    6. Downstream face of Rock Creek Diversion Dam, looking west (Gate raised to cut off flow to Rock Creek, weir section to left of photo) - Bitter Root Irrigation Project, Rock Creek Diversion Dam, One mile east of Como Dam, west of U.S. Highway 93, Darby, Ravalli County, MT

  13. 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

  14. 77 FR 43117 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-23

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... other management actions to protect resources downstream of Glen Canyon Dam, consistent with the...

  15. 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

  16. 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

  17. 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

  18. 72. AVALON DAM Photographic copy of historic photo, June ...

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

    72. AVALON DAM - Photographic copy of historic photo, June 16, 1916 (original print filed in Record Group 115, National Archives, Washington, D.C.) H.T.C., photographer 'AVALON DAM CYLINDER GATES' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  19. 78 FR 7810 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations...

  20. 76 FR 24516 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations...

  1. 77 FR 9265 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-16

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations...

  2. 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

  3. 3. View of the northern twothirds of the dam showing ...

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

    3. View of the northern two-thirds of the dam showing the Finch, Pruyn & Company intake structure and forebay canal on the right and the ice-covered log chute along the dam. Facing south-southwest. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  4. 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 872.6300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is...

  5. 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

  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. 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

  8. 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...

  9. 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....

  10. 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....

  11. 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...

  12. 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...

  13. 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

  14. 61. AVALON DAM Photographic copy of historic photo, 1907 ...

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

    61. AVALON DAM - Photographic copy of historic photo, 1907 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF AVALON DAM RECONSTRUCTION - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  15. 52. AVALON DAM Photographic copy of historic photo, c1890 ...

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

    52. AVALON DAM - Photographic copy of historic photo, c1890 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF SCOURWAY THROUGH AVALON DAM DISCHARGING WATER - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  16. 56. AVALON DAM Photographic copy of historic photo, December ...

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

    56. AVALON DAM - Photographic copy of historic photo, December 18, 1905 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'REMAINING PORTIONS OF WASHED OUT TEMPORARY DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  17. 75. AVALON DAM Photographic copy of historic photo, April ...

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

    75. AVALON DAM - Photographic copy of historic photo, April 10, 1938 (original print in '1938 Annual Report of the Carlsbad Project,' located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'AVALON DAM - CCC ROCK WORK AT SPILLWAY NO. 2' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  18. 50. AVALON DAM Photographic copy of historic photo, c1889 ...

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

    50. AVALON DAM - Photographic copy of historic photo, c1889 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'ROCK CUT AND DAM AT HEAD OF DITCH ABOVE EDDY, N.M.' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  19. 51. AVALON DAM Photographic copy of historic photo, c1889 ...

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

    51. AVALON DAM - Photographic copy of historic photo, c1889 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF EXCAVATION OF HEADGATE CHANNEL. ALSO SHOWS A PORTION OF DAM - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

  20. 4. ROSS DAM: CLOSE UP VIEW OF COFFERED TREATMENT OF ...

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

    4. ROSS DAM: CLOSE UP VIEW OF COFFERED TREATMENT OF DAM FACE TO ENSURE BETTER BONDING OF CONCRETE OF PLANNED ENLARGEMENT. THE VALVE HOUSE AT ELEVATION 1340 IS VISIBLE IN THE UPPER RIGHT, 1989. - Skagit Power Development, Ross Dam, 11.0 miles upstream from Newhalem on Skagit River, Newhalem, Whatcom County, WA

  1. 78 FR 21415 - Glen Canyon Dam Adaptive Management Work Group

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ...The Glen Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon Dam operations and other management actions to protect resources downstream of Glen Canyon Dam, consistent with the Grand Canyon Protection Act. The AMWG meets two to three times a...

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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 Paran√° 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

  9. Renwick Dam RCC stepped spillway research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Small Watershed Program administered through the USDA-Natural Resources Conservation Service (formerly the Soil Conservation Service) has provided technical and financial assistance for the construction of nearly 11,000 embankment dams across the U.S. The construction peak in the Small Watershe...

  10. 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…

  11. 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 ourÖ

  12. 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…

  13. Percy Quin Dam LiDAR Scan

    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....

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

    NASA Astrophysics Data System (ADS)

    Null, S. E.; Medellin-Azuara, J.; Lund, J. R.

    2012-12-01

    Dams provide water supply, flood protection, and hydropower generation benefits, but have also harmed native species by altering the natural flow regime and degrading aquatic and riparian habitat. Restoring some river reaches to free-flowing conditions may restore substantial environmental benefits, but at some economic cost. This study uses a systems analysis approach to evaluate removing rim dams in California's Central Valley to highlight dams that could be removed as well as existing dams that are most beneficial for providing water supply and hydropower benefits. CALVIN, an economic-engineering optimization model was used to evaluate water storage and scarcity from removing dams. A warm and dry climate model (GFDL CM2.1 A2 emissions scenario) for a 30 year period centered at 2085, and double population scenario for year 2050 water demands represent future conditions. Tradeoffs between water scarcity to urban, agricultural, and instream flow requirements were compared with additional river miles accessible to anadromous species following dam removal. Results show that existing infrastructure is most beneficial if operated as a system (ignoring many current political and 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. Incorporating environmental considerations into decision-making may lead to better solutions than focusing only on human benefits such as water supply, flood protection, hydropower generation, and recreation. Similarly, improving environmental flows can come at substantially lower economic cost, when viewed and operated as a system.Ratio of Surface Storage to Mean Annual Flow by Watershed

  15. Method For Flood Hydrograph Generation For Hydrological Dam Safety Assessment

    NASA Astrophysics Data System (ADS)

    Lohr, H.; Mueller, A.

    In a system of three serially connected reservoirs built at the beginning of the last century, the hydrological safety of the dams was analysed. Part of the study was the generation of a large sample of flood hydrographs. The generation of flood hydrographs is a stochastic procedure. A large number of events were computed with Monte-Carlo-simulation techniques by randomly draw- ing values from parameter distribution functions derived from a a large sample of measured values. It is required that the sample generated has the same statistical prop- erties as the underlying sample. In the specific case it was necessary to analyse the measured runoff to the reservoir-system at three significant inflow locations with dis- charge gages. To describe the start, maximum and shape of measured extreme flood hydrographs, parameters were identified, which define the mathematical functions chosen for generation. For these parameters distributions and correlations between the parameters could be found. Based on these parameters and correlation functions 10000 flood hydrographs (equivalent to 10000 years) were generated by randomly drawing parameters from the distribution functions assuring that cross correlation was observed. Based on regional extreme values of precipitation the plausibility of the hydrographs generated was checked for violation of physically defined limits of the rainfall runoff coefficient. The generated flood sample was then used as inflow bound- ary conditions to simulate the reservoir system with the operation model TALSIM 2.0 (see www.talsim.de). This procedure provides a distribution function of maximum reservoir levels as a basis of assessing the probability of failure of a dam structure. The probabilistic approach contains less uncertainty concerning inflow conditions. Although in the first step fixed initial conditions for reservoir levels were assumed, it can be coupled with distribution functions of lake levels if these vary widely during dominant flood periods.

  16. Uranium mill tailings neutralization: contaminant complexation and tailings leaching studies

    SciTech Connect

    Opitz, B.E.; Dodson, M.E.; Serne, R.J.

    1985-05-01

    Laboratory experiments were performed to compare the effectiveness of limestone (CaCO/sub 3/) and hydrated lime (Ca(OH)/sub 2/) for improving waste water quality through the neutralization of acidic uranium mill tailings liquor. The experiments were designed to also assess the effects of three proposed mechanisms - carbonate complexation, elevated pH, and colloidal particle adsorption - on the solubility of toxic contaminants found in a typical uranium mill waste solution. Of special interest were the effects each of these possible mechanisms had on the solution concentrations of trace metals such as Cd, Co, Mo, Zn, and U after neutralization. Results indicated that the neutralization of acidic tailings to a pH of 7.3 using hydrated lime provided the highest overall waste water quality. Both the presence of a carbonate source or elevating solution pH beyond pH = 7.3 resulted in a lowering of previously achieved water quality, while adsorption of contaminants onto colloidal particles was not found to affect the solution concentration of any constituent investigated. 24 refs., 8 figs., 19 tabs.

  17. Longitudinal dam interactions control channel morphology: The impacts of the Garrison and Oahe Dams on the Upper Missouri River

    NASA Astrophysics Data System (ADS)

    Skalak, K.; Benthem, A.; Schenk, E.; Hupp, C. R.; Galloway, J.; Nustad, R.

    2014-12-01

    Although the downstream impacts of dams on channel morphology and the upstream effects of dams on reservoir sedimentation are well documented, these effects were generally studied in isolation, with relatively little attention paid to their potential interaction along a river corridor. We examine the morphological and sedimentological changes in the Upper Missouri River, between the Garrison Dam in ND (operational in 1953) and Oahe Dam in SD (operational in 1959) (the Garrison Dam segment). Through historical aerial photography, stream gage data, and cross sectional surveys, we demonstrate that the influence of the upstream dam is still a major control of river dynamics when the backwater effects of the downstream reservoir begin. We propose a conceptual model of how interacting dams could affect river morphology, resulting in distinct and recognizable geomorphic sequences that we term "Inter-Dam Sequence". Based on previous research on the geomorphic adjustment and recovery of sediment loads downstream from large dams, we define a distance criterion for dam interaction. We use this criterion to demonstrate that there are more than 400 reaches on large rivers in the United States that could be geomorphically controlled by dam interactions, similar to the Garrison Dam segment.

  18. 33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Marshall Ford Dam and Reservoir... Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex. The Secretary of the Interior, through his agent, the Lower Colorado River Authority (LCRA) shall operate the Marshall Ford...

  19. 33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Marshall Ford Dam and Reservoir... Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex. The Secretary of the Interior, through his agent, the Lower Colorado River Authority (LCRA) shall operate the Marshall Ford...

  20. 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