WorldWideScience

Sample records for montana dam removals

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

    Science.gov (United States)

    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.

  2. Dam removal: Listening in

    Science.gov (United States)

    Foley, Melissa M.; Bellmore, James; O'Connor, James E.; Duda, Jeff; East, Amy E.; Grant, Gordon G.; Anderson, Chauncey; Bountry, Jennifer A.; Collins, Mathias J.; Connolly, Patrick J.; Craig, Laura S.; Evans, James E.; Greene, Samantha; Magilligan, Francis J.; Magirl, Christopher S.; Major, Jon J.; Pess, George R.; Randle, Timothy J.; Shafroth, Patrick B.; Torgersen, Christian; Tullos, Desiree D.; Wilcox, Andrew C.

    2017-01-01

    Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far, some general conclusions have emerged: (1) physical responses are typically fast, with the rate of sediment erosion largely dependent on sediment characteristics and dam-removal strategy; (2) ecological responses to dam removal differ among the affected upstream, downstream, and reservoir reaches; (3) dam removal tends to quickly reestablish connectivity, restoring the movement of material and organisms between upstream and downstream river reaches; (4) geographic context, river history, and land use significantly influence river restoration trajectories and recovery potential because they control broader physical and ecological processes and conditions; and (5) quantitative modeling capability is improving, particularly for physical and broad-scale ecological effects, and gives managers information needed to understand and predict long-term effects of dam removal on riverine ecosystems. Although these studies collectively enhance our understanding of how riverine ecosystems respond to dam removal, knowledge gaps remain because most studies have been short (methods in the U.S.

  3. USGS Dam Removal Science Database

    Science.gov (United States)

    Bellmore, J. Ryan; Vittum, Katherine; Duda, Jeff J.; Greene, Samantha L.

    2015-01-01

    This database is the result of an extensive literature search aimed at identifying documents relevant to the emerging field of dam removal science. In total the database contains 179 citations that contain empirical monitoring information associated with 130 different dam removals across the United States and abroad. Data includes publications through 2014 and supplemented with the U.S. Army Corps of Engineers National Inventory of Dams database, U.S. Geological Survey National Water Information System and aerial photos to estimate locations when coordinates were not provided. Publications were located using the Web of Science, Google Scholar, and Clearinghouse for Dam Removal Information.

  4. Conflicts Associated with Dam Removal in Sweden

    Directory of Open Access Journals (Sweden)

    Anna G. C. Lejon

    2009-12-01

    Full Text Available The increasing number of deteriorating old dams that need renovation or have lost their function make dam removal a viable management option. There are at least four major reasons for dam removal: safety, law and policy, economy, and ecology. Here we discuss 17 Swedish dams that were recently considered for removal. Because dam removal usually causes controversy, dam removal initiatives may succeed, fail, or result in a compromise such as a bypass channel for migrating fish. We identify and discuss three major obstructions to dam removal: funding, cultural-historical values, and threatened species. To facilitate dam removal, the reasons for, and the effects of, dam removal must be carefully explained, and the public and stakeholders must be kept informed. In complicated cases in which compromise solutions may be the most feasible outcome, the integration of the knowledge of different stakeholders is crucial. The involvement of diverse stakeholders increases their willingness to find compromises, thus avoiding conflicts and failures.

  5. 77 FR 2970 - Gibson Dam Hydroelectric Company, LLC, Montana; Notice of Availability of Final Environmental...

    Science.gov (United States)

    2012-01-20

    ... Energy Regulatory Commission Gibson Dam Hydroelectric Company, LLC, Montana; Notice of Availability of... 47897), the Office of Energy Projects has reviewed the application for license for the Gibson Dam Hydroelectric Project, located at the U.S. Department of the Interior, Bureau of Reclamation's Gibson dam on...

  6. Chemical - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  7. Physical - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  8. Biological - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  9. Toward policies and decision-making for dam removal.

    Science.gov (United States)

    Doyle, Martin W; Harbor, Jon M; Stanley, Emily H

    2003-04-01

    Dam removal has emerged as a critical issue in environmental management. Agencies responsible for dams face a drastic increase in the number of potential dam removals in the near future. Given limited resources, these agencies need to develop ways to decide which dams should be removed and in what order. The underlying science of dam removal is relatively undeveloped and most agencies faced with dam removal lack a coherent purpose for removing dams. These shortcomings can be overcome by the implementation of two policies by agencies faced with dam removal: (1) the development and adoption of a prioritization scheme for what constitutes an important dam removal, and (2) the establishment of minimum levels of analysis prior to decision-making about a dam removal. Federal and state agencies and the scientific community must encourage an initial experimental phase of dam removal during which only a few dams are removed, and these are studied intensively. This will allow for the development of the fundamental scientific understanding needed to support effective decision-making in the future and minimize the risk of disasters arising from poorly thought out dam removal decisions.

  10. Socioeconomic and Institutional Dimensions of Dam Removals: The Wisconsin Experience

    Science.gov (United States)

    Born; Genskow; Filbert; Hernandez-Mora; Keefer; White

    1998-05-01

    / There are tens of thousands of small dams in the United States; many of these aging structures are deteriorating. Governments and dam owners face decisions regarding repair or removal of these structures. Along with the many benefits society derives from dams and their impoundments, numerous recent ecological studies are revealing the extensive alteration and degradation of river ecosystems by dams. Dam removal-a principal restoration strategy-is an infrequent event. The major reasons for removal have been public safety and the high costs associated with repair; the goal of river ecosystem restoration now warrants greater attention. Substantial study is being given to the environmental aspects of dams and dam removals, but very little attention has been given to the socioeconomic and institutional dimensions associated with the removal of dams, although these factors play a significant role in the removal decision-making process. Based on a case study of dam removals in Wisconsin-where more than 30 of the state's 3600 small dams have been removed in the past few decades-legal, financial, and socioeconomic issues associated with dam removal are documented and assessed. Dam removal has been complex and contentious, with limited community-based support for removal and loss of the impounded waters. In cases examined here, the estimated costs of repairing a dam averaged more than three times the cost of removal. The availability of governmental financing has been a key determinant in removal decisions. Watershed-scale ecological considerations are not major factors for most local interests. As watershed management and restoration increasingly include dam removal options as part of an integrated strategy, more attention will need to be focused on socioeconomic factors and stakeholder perspectives-variables that strongly influence the viability of this management alternative.KEY WORDS: Dam removal; River restoration; Institutions; Stakeholders

  11. Final Independent External Peer Review Report for the Intake Diversion Dam Modification Lower Yellowstone Project, Montana Draft Supplement to the 26 April 2010 Environmental Assessment and Appendices

    Science.gov (United States)

    2013-02-08

    February 8, 2013 Final Independent External Peer Review Report for the Intake Diversion Dam Modification Lower Yellowstone Project, Montana...Final Independent External Peer Review Report for the Intake Diversion Dam Modification Lower Yellowstone Project, Montana Draft Supplement to the...Intake Project IEPR Final IEPR Report Intake Project IEPR Final IEPR Report Final Independent External Peer Review Report for the

  12. River restoration by dam removal: Enhancing connectivity at watershed scales

    Directory of Open Access Journals (Sweden)

    F.J. Magilligan

    2016-05-01

    Full Text Available Abstract The prolonged history of industrialization, flood control, and hydropower production has led to the construction of 80,000 dams across the U.S. generating significant hydrologic, ecological, and social adjustments. With the increased ecological attention on re-establishing riverine connectivity, dam removal is becoming an important part of large-scale river restoration nationally, especially in New England, due to its early European settlement and history of waterpower-based industry. To capture the broader dimensions of dam removal, we constructed a GIS database of all inventoried dams in New England irrespective of size and reservoir volume to document the magnitude of fragmentation. We compared the characteristics of these existing dams to the attributes of all removed dams over the last ∼25 years. Our results reveal that the National Inventory of Dams significantly underestimates the actual number of dams (4,000 compared to >14,000. To combat the effects of these ecological barriers, dam removal in New England has been robust with 127 dams having been removed between ca. 1990–2013. These removed dams range in size, with the largest number (30% ranging between 2–4 m high, but 22% of the removed dams were between 4–6 m. They are not isolated to small drainage basins: most drained watersheds between 100–1,000 km2. Regionally, dam removal has re-connected ∼3% (3,770 river km of the regional river network although primarily through a few select dams where abundant barrier-free river lengths occur, suggesting that a more strategic removal approach has the opportunity to enhance the magnitude and rate of river re-connection. Given the regional-scale restoration of forest cover and water quality over the past century, dam removal offers a significant opportunity to capitalize on these efforts, providing watershed scale restoration and enhancing watershed resilience in the face of significant regional and global anthropogenic

  13. Will Dam Removal Increase Nitrogen Flux to Estuaries?

    Directory of Open Access Journals (Sweden)

    Arthur J. Gold

    2016-11-01

    Full Text Available To advance the science of dam removal, analyses of functions and benefits need to be linked to individual dam attributes and effects on downstream receiving waters. We examined 7550 dams in the New England (USA region for possible tradeoffs associated with dam removal. Dam removal often generates improvements for safety or migratory fish passage but might increase nitrogen (N flux and eutrophication in coastal watersheds. We estimated N loading and removal with algorithms using geospatial data on land use, stream flow and hydrography. We focused on dams with reservoirs that increase retention time at specific points of river reaches, creating localized hotspots of elevated N removal. Approximately 2200 dams with reservoirs had potential benefits for N removal based on N loading, retention time and depth. Across stream orders, safety concerns on these N removal dams ranged between 28% and 44%. First order streams constituted the majority of N removal dams (70%, but only 3% of those were classified as high value for fish passage. In cases where dam removal might eliminate N removal function from a particular reservoir, site-specific analyses are warranted to improve N delivery estimates and examine alternatives that retain the reservoir while enhancing fish passage and safety.

  14. Dam removal increases American eel abundance in distant headwater streams

    Science.gov (United States)

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.

    2012-01-01

    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  15. The Social, Historical, and Institutional Contingencies of Dam Removal

    Science.gov (United States)

    Magilligan, F. J.; Sneddon, C. S.; Fox, C. A.

    2017-06-01

    Environmental managers in the United States and elsewhere are increasingly perceiving dam removal as a critical tool for river restoration and enhancing watershed resilience. In New England, over 125 dams have been dismantled for ecological and economic rationales. A surprising number of these removals, including many that are ongoing, have generated heated conflicts between restoration proponents and local communities who value their dammed landscapes. Using a comparative case study approach, we examine the environmental conflict around efforts to remove six dams in New England. Each of these removal efforts followed quite different paths and resultant outcomes: successful removal, stalled removal, and failure despite seemingly favorable institutional conditions. Lengthy conflicts often transpired in instances where removals occurred, but these were successfully arbitrated by paying attention to local historical-geographical conditions conducive to removal and by brokering effective compromises between dam owners and the various local actors and stakeholders involved in the removal process. Yet our results across all cases suggest that these are necessary, but not sufficient conditions for restoration through dam removal since a similar set of conditions typified cases where removals are continuously stalled or completely halted. Scholars examining the intersection between ecological restoration and environmental politics should remain vigilant in seeking patterns and generalities across cases of environmental conflict in order to promote important biophysical goals, but must also remain open to the ways in which those goals are thwarted and shaped by conflicts that are deeply contingent on historical-geographical conditions and broader institutional networks of power and influence.

  16. The Social, Historical, and Institutional Contingencies of Dam Removal.

    Science.gov (United States)

    Magilligan, F J; Sneddon, C S; Fox, C A

    2017-02-25

    Environmental managers in the United States and elsewhere are increasingly perceiving dam removal as a critical tool for river restoration and enhancing watershed resilience. In New England, over 125 dams have been dismantled for ecological and economic rationales. A surprising number of these removals, including many that are ongoing, have generated heated conflicts between restoration proponents and local communities who value their dammed landscapes. Using a comparative case study approach, we examine the environmental conflict around efforts to remove six dams in New England. Each of these removal efforts followed quite different paths and resultant outcomes: successful removal, stalled removal, and failure despite seemingly favorable institutional conditions. Lengthy conflicts often transpired in instances where removals occurred, but these were successfully arbitrated by paying attention to local historical-geographical conditions conducive to removal and by brokering effective compromises between dam owners and the various local actors and stakeholders involved in the removal process. Yet our results across all cases suggest that these are necessary, but not sufficient conditions for restoration through dam removal since a similar set of conditions typified cases where removals are continuously stalled or completely halted. Scholars examining the intersection between ecological restoration and environmental politics should remain vigilant in seeking patterns and generalities across cases of environmental conflict in order to promote important biophysical goals, but must also remain open to the ways in which those goals are thwarted and shaped by conflicts that are deeply contingent on historical-geographical conditions and broader institutional networks of power and influence.

  17. Institutionalizing the option of dam removal: the New Hampshire initiative.

    Science.gov (United States)

    Lindloff, S D

    2003-01-01

    For two years, the State of New Hampshire has worked to institutionalize the option of dam removal. The high gradient streams that flow through the granite hills and mountains of this small northeastern state provided ideal conditions for dam construction, particularly during America's Industrial Revolution of the 1800s when mills were constructed throughout the area. With more than 4,800 dams in the state's database, there are many opportunities for the removal of dams that no longer serve a useful purpose, have become a public safety hazard and impact the river environment. Efforts to facilitate removal of dams in New Hampshire include the formation of a River Restoration Task Force and the creation of a dam removal program within the state agency responsible for regulating dams. This has led to the removal of two dams in the past year, with approximately ten additional projects in various stages of planning. A history of this agency-led initiative, as well as a discussion of the program's strengths, challenges and goals for the future are presented.

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

    Science.gov (United States)

    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.

  19. Elwha Master Datafile - Elwha Dam Removal - Nearshore monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Removal of two dams on the Elwha River, Washington will help restore natural sediment processes to the coastal environment near the river mouth. We are interested in...

  20. River turbidity and sediment loads during dam removal

    Science.gov (United States)

    Warrick, Jonathan A.; Duda, Jeffrey J.; Magirl, Christopher S.; Curran, Chris A.

    2012-01-01

    Dam decommissioning has become an important means for removing unsafe or obsolete dams and for restoring natural fluvial processes, including discharge regimes, sediment transport, and ecosystem connectivity [Doyle et al., 2003]. The largest dam-removal project in history began in September 2011 on the Elwha River of Washington State (Figure 1a). The project, which aims to restore the river ecosystem and increase imperiled salmon populations that once thrived there, provides a unique opportunity to better understand the implications of large-scale river restoration.

  1. Effect of rubber dam on mercury exposure during amalgam removal.

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    Kremers, L; Halbach, S; Willruth, H; Mehl, A; Welzl, G; Wack, F X; Hickel, R; Greim, H

    1999-06-01

    It was the aim of this investigation to treat 20 volunteers with maximally 5 amalgam fillings by the same comprehensive protocol in which all removals with (n = 8) and without (n = 12) rubber dam had been performed within a few months. Nine amalgam-related parameters indicated a close matching of both groups before removal. In the group without rubber dam, mercury (Hg) levels in plasma increased significantly above preremoval values at days 1 and 3 after removal; they decreased significantly below preremoval values at day 30 in the rubber-dam group and at day 100 in both groups. Excretion rates did not increase significantly in either group, but decreased significantly at day 100 in the protected group. Peak plasma-Hg was 0.6 ng/mL on average at day one and decreased with halftimes of 3 and 43 d in subjects protected by rubber dam. The results indicated that concentrations of total mercury in plasma responded rapidly to changes in the amalgam status and reflected the actual absorption most reliably. Notably, plasma-Hg levels were sensitive enough to detect a transient attenuation of the additional exposure by using rubber dam during the removal of only a few fillings. However, being small in magnitude and lasting 100 d at best, the rubber-dam effect had minor toxicological relevance.

  2. Damned If You Do, Dammed If You Don't: Debates on Dam Removal in the Swedish Media

    Directory of Open Access Journals (Sweden)

    Dolly Jørgensen

    2013-03-01

    Full Text Available Dam removal is an increasingly common practice. Dams are removed for various reasons, with safety, economics, and ecosystem restoration being the most common. However, dam removals often cause controversy. Riparian land owners and local communities often have a negative view of removal, and their reasons vary. It may be the loss of recreational benefits such as swimming and boating, loss of cultural and historical context tied to the dam, or fear that removal may have a negative effect on aesthetic values. Because controversies are often picked up by local media, and media in itself is an important channel to build support around a cause, the way in which dam removals are reported and discussed in the media is likely to influence the debate. Here, we examine the ways in which proponents and opponents of dam removal frame the services provided by two contrasting ecosystems, i.e., an existing dam and the potential stream without a dam, by performing a media discourse analysis of the reasons given for removal and the reasons presented for the dam to remain in place. Our source material includes Internet-based newspaper articles and their associated public comments in four dam removal controversies in Sweden. Our analysis indicates that public opposition is not based on knowledge deficiency, where more information will lead to better ecological decision-making, as is sometimes argued in dam removal science; it is instead a case of different understandings and valuation of the environment and the functions it provides.

  3. A Hidden-Removal Model of Dam Perspective Drawing

    Institute of Scientific and Technical Information of China (English)

    WANG Zi-ru; ZHOU Hui-cheng; LI Ming-qiu

    2011-01-01

    Aming at water conservancy project visualization, a hidden-removal method of dam perspective drawings is realized by building a hidden-removal mathematical model for overlapping points location to set up the hidden relationship among point and plane, plane and plane in space. On this basis, as an example of panel rockfill dam, a dam hidden-removal perspective drawing is generated in different directions and different visual angles through adapting VC++ and OpenGL visualizing technology. The results show that the data construction of the model is simple which can overcome the disadvantages of considerable and complicated calculation. This method also provides the new means to draw hidden-removal perspective drawings for those landforms and ground objects.

  4. Elwha River dam removal-Rebirth of a river

    Science.gov (United States)

    Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    After years of planning for the largest project of its kind, the Department of the Interior will begin removal of two dams on the Elwha River, Washington, in September 2011. For nearly 100 years, the Elwha and Glines Canyon Dams have disrupted natural processes, trapping sediment in the reservoirs and blocking fish migrations, which changed the ecology of the river downstream of the dams. All five Pacific salmon species and steelhead-historically present in large numbers-are locally extirpated or persist in critically low numbers. Upstream of the dams, more than 145 kilometers of pristine habitat, protected inside Olympic National Park, awaits the return of salmon populations. As the dams are removed during a 2-3 year project, some of the 19 million cubic meters of entrapped sediment will be carried downstream by the river in the largest controlled release of sediment into a river and marine waters in history. Understanding the changes to the river and coastal habitats, the fate of sediments, and the salmon recolonization of the Elwha River wilderness will provide useful information for society as future dam removals are considered.

  5. Ecosystem Response During the Removal of the Elwha River Dams

    Science.gov (United States)

    Pess, G. R.; McHenry, M.; Liermann, M. C.; Moses, R.; Denton, K.; McMillan, J.; Brenkman, S.; Duda, J.; Peters, R.; Anderson, J.; Quinn, T.

    2015-12-01

    Over the last century, the two dams blocked the upstream movement of anadromous fish to over 90% of the Elwha River watershed on the Olympic Peninsula of Washington State. These dams also restricted the downstream movement of sediment, wood, and other organic materials to the lower river and estuary. Populations of all Pacific salmon species and steelhead in the Elwha became critically low, habitat complexity decreased below the dams, and downstream coastal habitats became sediment starved. Simultaneous deconstruction of the two dams began in September 2011 was completed in September of 2014. The recent removal of the dams has been an opportunity to explore linkages among changes in sediment supply, salmonid populations, and ecosystem attributes. Preliminary findings focus on the delivery of millions of metric tonnes of sediment to the main river, its floodplain, and nearshore, the re-establishment of a natural wood delivery regime, the re-colonization of the upper watershed by anadromous fish, insights into functional relationships among salmonid populations and life history strategies, and the associated effects of all these elements on the aquatic and terrestrial foodwebs. This talk will provide an overview of the Elwha restoration project, and highlight recent changes observed during dam removal.

  6. Simulation and control of sediment transport due to dam removal

    Science.gov (United States)

    This paper presents two case studies of post dam removal sedimentation in the United States. Two different one-dimensional channel evolution simulation models were used: CCHE1D and CONCEPTS, respectively. The first case is the application of CCHE1D to assess a long-term morphological response to the...

  7. Simulation of morphological changes due to dam removal

    Science.gov (United States)

    In this chapter, a brief review of numerical models and their applications for impact assessment of dam removal on sediment transport and morphological changes in alluvial rivers is given. As an example, a one-dimensional river flow and sediment transport model, CCHE1D, is applied to assess morpholo...

  8. Landscape context and the biophysical response of rivers to dam removal in the United States

    Science.gov (United States)

    Foley, Melissa M.; Magilligan, Francis J.; Torgersen, Christian; Major, Jon J.; Anderson, Chauncey; Connolly, Patrick J.; Wieferich, Daniel; Shafroth, Patrick B.; Evans, James E.; Infante, Dana M.; Craig, Laura

    2017-01-01

    Dams have been a fundamental part of the U.S. national agenda over the past two hundred years. Recently, however, dam removal has emerged as a strategy for addressing aging, obsolete infrastructure and more than 1,100 dams have been removed since the 1970s. However, only 130 of these removals had any ecological or geomorphic assessments, and fewer than half of those included before- and after-removal (BAR) studies. In addition, this growing, but limited collection of dam-removal studies is limited to distinct landscape settings. We conducted a meta-analysis to compare the landscape context of existing and removed dams and assessed the biophysical responses to dam removal for 63 BAR studies. The highest concentration of removed dams was in the Northeast and Upper Midwest, and most have been removed from 3rd and 4th order streams, in low-elevation (landscape settings, which limits predictive capacity in other environmental settings. Biophysical responses to dam removal varied by landscape cluster, indicating that landscape features are likely to affect biophysical responses to dam removal. However, biophysical data were not equally distributed across variables or clusters, making it difficult to determine which landscape features have the strongest effect on dam-removal response. To address the inconsistencies across dam-removal studies, we provide suggestions for prioritizing and standardizing data collection associated with dam removal activities.

  9. Dam Removals and River Restoration in International Perspective

    Directory of Open Access Journals (Sweden)

    Chris S. Sneddon

    2017-10-01

    Full Text Available In the Anthropocene era, questions over institutions, economics, culture and politics are central to the promotion of water-society relations that enhance biophysical resilience and democratic modes of environmental governance. The removal of dams and weirs from river systems may well signal an important shift in how human actors value and utilize rivers. Yet the removal of water infrastructure is often lengthy, institutionally complex, and characterized by social conflict. This Special Issue draws insights from case studies of recent efforts in North America and Europe to restore river systems through dam and weir removal. These cases include both instances where removal has come to fruition in conjunction with efforts to rehabilitate aquatic systems and instances where removal has been stymied by a constellation of institutional, political and cultural factors. Drawing from diverse theoretical frames and methodological approaches, the authors present novel ways to conceptualize water-society relations using the lens of dam removal and river restoration, as well as crucial reminders of the multiple biophysical and social dimensions of restoration initiatives for water resource practitioners interested in the rehabilitation of socioecological systems.

  10. Summary of Hailstone NWR dam removal meeting with MTDEQ

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Summary of the February 12, 2009 with the U.S. Fish and Wildlife Service, the Montana Department of Environmental Quality (MTDEQ), Montana Bureau of Mines and...

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

    Science.gov (United States)

    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.

  12. Dam Removal Information Portal (DRIP)—A map-based resource linking scientific studies and associated geospatial information about dam removals

    Science.gov (United States)

    Duda, Jeffrey J.; Wieferich, Daniel J.; Bristol, R. Sky; Bellmore, J. Ryan; Hutchison, Vivian B.; Vittum, Katherine M.; Craig, Laura; Warrick, Jonathan A.

    2016-08-18

    The removal of dams has recently increased over historical levels due to aging infrastructure, changing societal needs, and modern safety standards rendering some dams obsolete. Where possibilities for river restoration, or improved safety, exceed the benefits of retaining a dam, removal is more often being considered as a viable option. Yet, as this is a relatively new development in the history of river management, science is just beginning to guide our understanding of the physical and ecological implications of dam removal. Ultimately, the “lessons learned” from previous scientific studies on the outcomes dam removal could inform future scientific understanding of ecosystem outcomes, as well as aid in decision-making by stakeholders. We created a database visualization tool, the Dam Removal Information Portal (DRIP), to display map-based, interactive information about the scientific studies associated with dam removals. Serving both as a bibliographic source as well as a link to other existing databases like the National Hydrography Dataset, the derived National Dam Removal Science Database serves as the foundation for a Web-based application that synthesizes the existing scientific studies associated with dam removals. Thus, using the DRIP application, users can explore information about completed dam removal projects (for example, their location, height, and date removed), as well as discover sources and details of associated of scientific studies. As such, DRIP is intended to be a dynamic collection of scientific information related to dams that have been removed in the United States and elsewhere. This report describes the architecture and concepts of this “metaknowledge” database and the DRIP visualization tool.

  13. Removing Dams, Constructing Science: Coproduction of Undammed Riverscapes by Politics, Finance, Environment, Society and Technology

    Directory of Open Access Journals (Sweden)

    Zbigniew J. Grabowski

    2017-10-01

    Full Text Available Dam removal in the United States has continued to increase in pace and scope, transitioning from a dam-safety engineering practice to an integral component of many large-scale river restoration programmes. At the same time, knowledge around dam removals remains fragmented by disciplinary silos and a lack of knowledge transfer between communities of practice around dam removal and academia. Here we argue that dam removal science, as a study of large restoration-oriented infrastructure interventions, requires the construction of an interdisciplinary framework to integrate knowledge relevant to decision-making on dam removal. Drawing upon infrastructure studies, relational theories of coproduction of knowledge and social life, and advances within restoration ecology and dam removal science, we present a preliminary framework of dams as systems with irreducibly interrelated political, financial, environmental, social, and technological dimensions (PFESTS. With this framework we analyse three dam removals occurring over a similar time period and within the same narrow geographic region (the Mid-Columbia Region in WA and OR, USA to demonstrate how each PFESTS dimension contributed to the decision to remove the dam, how it affected the process of removing the dam, and how those dimensions continue to operate post removal in each watershed. We conclude with a discussion of a joint research and practice agenda emerging out of the PFESTS framing.

  14. Examination of physical and regulatory variables leading to small dam removal in Wisconsin.

    Science.gov (United States)

    Orr, Cailin H; Roth, Brian M; Forshay, Kenneth J; Gonzales, James D; Papenfus, Michael M; Wassell, Rebecca D G

    2004-01-01

    The decision to remove or repair a dam depends on multiple variables, many of which encompass both physical and social factors. In Wisconsin, the Department of Natural Resources is mandated to inspect small dams every ten years. A safety inspection often acts as a trigger event to a dam removal or repair decision. Although the issues surrounding a dam removal decision are often couched as ecological, these decisions are influenced by their social and regulatory context. In this work, we examine descriptive variables of Wisconsin dams that were inspected and consequently removed or maintained between 1985 and 1990. We hypothesize that geographic location, height of dam, size of impoundment, age of dam, and type of ownership determine the likelihood of a safety inspection, and the subsequent likelihood of removal. Using a logistic model, we find that publicly owned dams had the greatest probability of inspection after 1985. Of these dams, older dams and those with smaller impoundments were most likely to be removed. We were unable to build a strong predictive model for dam removal with our suite of variables, suggesting that a community's decision to remove or maintain a dam is complex and heterogeneous.

  15. Challenges to natural process restoration: common dam removal management concerns

    Science.gov (United States)

    Collins, M. J.; Tullos, D. D.; Bellmore, J. R.; Bountry, J.; Connolly, P. J.; Shafroth, P. B.; Wilcox, A. C.

    2015-12-01

    Practitioners must make dam removal decisions in spite of uncertainty about physical and ecological responses. This can result in implementing structural controls or other interventions at a site to avoid anticipated negative effects, sometimes even if a given concern is not warranted. We used a newly available dam removal science database and other information sources to explore seven frequently raised issues we call "Common Management Concerns" (CMCs), investigating their occurrence and the contributing biophysical controls. We describe these controls to enable managers to better assess if further analyses are warranted at their sites before interventions are planned and implemented. The CMCs addressed are: rate and degree of reservoir sediment erosion; drawdown impacts on local water infrastructure; excessive channel incision; downstream sediment aggradation; elevated turbidity; colonization of reservoir sediments by non-native plants; and expansion of invasive fish. The relative dearth of case studies available for many CMCs limited the generalizable conclusions we could draw about prevalence, but the available data and established understanding of relevant processes revealed important biophysical phenomena controlling the likelihood of CMC occurrence. To assess CMC risk, we recommend managers concurrently evaluate if site conditions suggest the ecosystem, infrastructure, or other human uses will be negatively affected if the biophysical phenomenon producing the CMC occurs. We show how many CMCs have one or more controls in common, facilitating the identification of multiple risks at a site, and demonstrate why CMC risks should be considered in the context of other important factors like watershed disturbance history, natural variability, and dam removal tradeoffs. Better understanding CMCs and how to evaluate them will enable practitioners to avoid unnecessary interventions and thus maximize opportunities for working with natural processes to restore river

  16. Status and trends of dam removal research in the United States

    Science.gov (United States)

    Bellmore, James; Duda, Jeff; Craig, Laura; Greene, Samantha L.; Torgersen, Christian; Collins, Mathias J.; Vittum, Katherine

    2017-01-01

    Aging infrastructure coupled with growing interest in river restoration has driven a dramatic increase in the practice of dam removal. With this increase, there has been a proliferation of studies that assess the physical and ecological responses of rivers to these removals. As more dams are considered for removal, scientific information from these dam-removal studies will increasingly be called upon to inform decisions about whether, and how best, to bring down dams. This raises a critical question: what is the current state of dam-removal science in the United States? To explore the status, trends, and characteristics of dam-removal research in the U.S., we searched the scientific literature and extracted basic information from studies on dam removal. Our literature review illustrates that although over 1200 dams have been removed in the U.S., fewer than 10% have been scientifically evaluated, and most of these studies were short in duration ( < 4 years) and had limited (1–2 years) or no pre-removal monitoring. The majority of studies focused on hydrologic and geomorphic responses to removal rather than biological and water-quality responses, and few studies were published on linkages between physical and ecological components. Our review illustrates the need for long-term, multidisciplinary case studies, with robust study designs, in order to anticipate the effects of dam removal and inform future decision making.

  17. Watershed restoration: planning and implementing small dam removals to maximize ecosystem services

    Science.gov (United States)

    Tonitto, C.; Riha, S. J.

    2016-12-01

    River restoration and enhancing watershed connectivity is of growing concern in industrialized nations. The past two decades have seen a number of small dam removals, though many removals remain unstudied and poorly documented. We summarize socio-economic and biophysical lessons learned during the past two decades of accelerated activity regarding small dam removals throughout the United States. We present frameworks for planning and implementing removals developed by interdisciplinary engagement. Toward the goal of achieving thorough dam removal planning, we present outcomes from well-documented small dam removals covering ecological, chemical, and physical change in rivers post-dam removal, including field observation and modeling methodologies. Guiding principles of a dam removal process should include: 1) stakeholder engagement to navigate the complexity of watershed landuse, 2) an impacts assessment to inform the planning process, 3) pre- and post-dam removal observations of ecological, chemical and physical properties, 4) the expectation that there are short- and long-term ecological dynamics with population recovery depending on whether dam impacts were largely related to dispersion or to habitat destruction, 5) an expectation that changes in watershed chemistry are dependent on sediment type, sediment transport and watershed landuse, and 6) rigorous assessment of physical changes resulting from dam removal, understanding that alteration in hydrologic flows, sediment transport, and channel evolution will shape ecological and chemical dynamics, and shape how stakeholders engage with the watershed.

  18. Assessing post-dam removal sediment dynamics using the CONCEPTS computer model

    Science.gov (United States)

    Dam removal will impact stream morphology not just locally, but both far upstream and downstream. There is a critical need for tools to predict the rates, magnitudes, and mechanisms by which sediment is removed from a reservoir following dam removal, as well as for tools to predict where this sedime...

  19. Synthesis of common management concerns associated with dam removal

    Science.gov (United States)

    Tullos, Desiree D.; Collins, Mathias J.; Bellmore, J. Ryan; Bountry, Jennifer A.; Connolly, Patrick J.; Shafroth, Patrick B.; Wilcox, Andrew C.

    2016-01-01

    Managers make decisions regarding if and how to remove dams in spite of uncertainty surrounding physical and ecological responses, and stakeholders often raise concerns about certain negative effects, regardless of whether or not these concerns are warranted at a particular site. We used a dam-removal science database supplemented with other information sources to explore seven frequently-raised concerns, herein Common Management Concerns (CMCs). We investigate the occurrence of these concerns and the contributing biophysical controls. The CMCs addressed are: degree and rate of reservoir sediment erosion, excessive channel incision upstream of reservoirs, downstream sediment aggradation, elevated downstream turbidity, drawdown impacts on local water infrastructure, colonization of reservoir sediments by non-native plants, and expansion of invasive fish. Biophysical controls emerged for some of the concerns, providing managers with information to assess whether a given concern is likely to occur at a site. To fully assess CMC risk, managers should concurrently evaluate site conditions and identify the ecosystem or human uses that will be negatively affected if the biophysical phenomenon producing the CMC occurs. We show how many CMCs have one or more controls in common, facilitating the identification of multiple risks at a site, and demonstrate why CMC risks should be considered in the context of other factors like natural watershed variability and disturbance history.

  20. Simulating daily water temperatures of the Klamath River under dam removal and climate change scenarios

    Science.gov (United States)

    Perry, Russell W.; Risley, John C.; Brewer, Scott J.; Jones, Edward C.; Rondorf, Dennis W.

    2011-01-01

    A one-dimensional daily averaged water temperature model was used to simulate Klamath River temperatures for two management alternatives under historical climate conditions and six future climate scenarios. The analysis was conducted for the Secretarial Determination on removal of four hydroelectric dams on the Klamath River. In 2012, the Secretary of the Interior will determine if dam removal and implementation of the Klamath Basin Restoration Agreement (KBRA) (Klamath Basin Restoration Agreement, 2010) will advance restoration of salmonid fisheries and is in the public interest. If the Secretary decides dam removal is appropriate, then the four dams are scheduled for removal in 2020.

  1. River Restoration by Dam Removal: Assessing Riverine Re-Connectivity Across New England

    Science.gov (United States)

    Magilligan, F. J.; Nislow, K. H.; Graber, B.; Sneddon, C.; Fox, C.; Martin, E.

    2014-12-01

    The impacts of dams in New England are especially acute as it possesses one of the highest densities of dams in the US, with the NID documenting more than 4,000 dams, and state agency records indicating that >14,000 dams are peppered throughout the landscape. This large number of dams contributes to pervasive watershed fragmentation, threatening the ecological integrity of rivers and streams, and in the case of old, poorly maintained structures, posing a risk to lives and property. These concerns have generated active dam removal efforts throughout New England. To best capture the geomorphic, hydrologic, and potential ecological effects of dam removal at a regional level, we have compiled a dataset of 127 removed dams in New England, which includes information about structural characteristics, georectified locations, and key watershed attributes (including basin size, distance to next upstream obstacle, and number of free-flowing river kms opened up). Our specific research questions address (1) what is the spatial distribution of removed dams and how does this pattern relate to stated management goals of restoring critical habitat for native resident freshwater and diadromous fish, (2) what are the structural or management commonalities in dam types that have been removed, and (3) what has been the incremental addition of free-flowing river length? Rather than reflecting an overall management prioritization strategy, results indicate that dam removals are characterized more by opportunistic removals. For example, despite a regional emphasis on diadromous fish protection and restoration, most removals are inland rather than coastal settings. Most of the removed dams were small (~ 45% 2,300 river kms over the past several decades, with implication for both resident and diadromous fish, and with many removals located in mid-sized rivers that are a key link between upstream and downstream/coastal aquatic ecosystems.

  2. Undamming rivers: a review of the ecological impacts of dam removal.

    Science.gov (United States)

    Bednarek, A T

    2001-06-01

    Dam removal continues to garner attention as a potential river restoration tool. The increasing possibility of dam removal through the FERC relicensing process, as well as through federal and state agency actions, makes a critical examination of the ecological benefits and costs essential. This paper reviews the possible ecological impacts of dam removal using various case studies. Restoration of an unregulated flow regime has resulted in increased biotic diversity through the enhancement of preferred spawning grounds or other habitat. By returning riverine conditions and sediment transport to formerly impounded areas, riffle/pool sequences, gravel, and cobble have reappeared, along with increases in biotic diversity. Fish passage has been another benefit of dam removal. However, the disappearance of the reservoir may also affect certain publicly desirable fisheries. Short-term ecological impacts of dam removal include an increased sediment load that may cause suffocation and abrasion to various biota and habitats. However, several recorded dam removals have suggested that the increased sediment load caused by removal should be a short-term effect. Pre-removal studies for contaminated sediment may be effective at controlling toxic release problems. Although monitoring and dam removal studies are limited, a continued examination of the possible ecological impacts is important for quantifying the resistance and resilience of aquatic ecosystems. Dam removal, although controversial, is an important alternative for river restoration.

  3. Assessing the Ecological and Geomorphic Context of Dam Removals in the United States

    Science.gov (United States)

    Magilligan, F. J.; Foley, M.; Torgersen, C. E.; Major, J. J.; Anderson, C.; Connolly, P. J.; Shafroth, P. B.; Evans, J. E.

    2016-12-01

    Dams have been a fundamental part of our national agenda over the past two hundred years; recently, however, dam removal has emerged as a significant national strategy and more than 1,100 dams have been removed since ca. 1970. A recent national assessment revealed that only 130 of these removals had any ecological or geomorphic assessments, and only 35 included both. To better assess the current state of dam-removal science, we utilized an extensive data set compiled by American Rivers, which contained geospatial attributes of more than 850 dams removed in the U.S. We used this geospatial information in combination with the National Hydrography Dataset (NHDPlus) and other watershed-scale assessment interfaces that provided data on eco-regions, national land cover attributes, and cumulative watershed disturbance to determine the geographic, ecological, and geomorphic context of removed dams. The highest concentration of removed dams is in the Northeast and Upper Midwest. Nationally, they have been removed mainly from 1st order streams, but more than 40% are on 3rd and 4th order streams. Geomorphically, most removals are in lowland settings with 87% at elevations Ecologically, watersheds above removed dams are predominantly forested, mainly in broadleaf deciduous settings of the Ridge and Valley, Northern Piedmont, NE Highland, and NE Coastal Zone EPA Level III eco-region classes. Watershed scale assessments indicate most (37%) removals are in watersheds with the lowest cumulative disturbance scores, showing removals have made high-quality habitat available. Principal component analyses showed a strong correlation of removals based on low slope, low elevation, large watershed area, and low cumulative disturbance. Many of the studied removals also have these characteristics, suggesting that our understanding of responses to dam removals is based on a limited range of ecological and geomorphic settings, which limits predictive capacity in other environmental settings.

  4. Dam removal, connectivity, and aquatic resources in the St. Regis River Watershed, New York

    Science.gov (United States)

    McKenna, James E.; Hanak, Kaitlin; DeVilbiss, Katharine; David, Anthony; Johnson, James H.

    2015-10-09

    The decommissioning and planned removal of the Hogansburg Dam on the St. Regis River in New York has stimulated interest in the potential effects of that barrier removal on the St. Regis watershed. There will be immediate and systemic effects of the Hogansburg Dam removal, which may include inundation of habitats below the dam or dewatering of habitats above the dam, possibly affecting local fish assemblages and (or) local native mussel assemblages; and expansion of stream network connectivity, which has the potential to open a large area of the watershed to migratory aquatic species. Information was collected about biota, water quality, sediment distribution, riverbed dimensions in the vicinity of the dam, and habitat characteristics of headwater sample sites. Complete fish assemblages were collected, but species of special concern associated with the connectivity changes included, American Eel, Atlantic Salmon, Brook Trout, Eastern Sand Darter, and Lake Sturgeon. Freshwater mussels in the vicinity of the dam also were examined and may be at risk of exposure (without a rescue plan) after dam removal. Reservoir sediment will be transported downstream and will alter aquatic habitat as it moves through the system. The dam removal will open more than 440 kilometers of stream habitat to migratory species, allowing them to more easily complete their life cycles. Fish assemblages above the dam may be altered by migrating fishes, but resident Brook Trout are not expected to be adversely affected.

  5. Simulation and control of morphological changes due to dam removal in the Sandy River, Oregon, USA

    Science.gov (United States)

    Ding, Y.; Altinakar, M. S.

    2015-03-01

    A one-dimensional channel evolution simulation model (CCHE1D) is applied to assess morphological changes in a reach of the Sandy River, Oregon, USA, due to the Marmot Dam removal in 2007. Sediment transport model parameters (e.g. sediment transport capacity, bed roughness coefficient) were calibrated using observed bed changes after the dam removal. The validated model is then applied to assess long-term morphological changes in response to a 10-year hydrograph selected from historical storm water records. The long-term assessment of sedimentation gives a reasonable prediction of morphological changes, expanding erosion in reservoir and growing deposition immediately downstream of the dam site. This prediction result can be used for managing and planning river sedimentation after dam removal. A simulation-based optimization model is also applied to determine the optimal sediment release rates during dam-removal that will minimize the morphological changes in the downstream reaches.

  6. Geomorphic responses to dam removal in the United States – a two-decade perspective

    Science.gov (United States)

    Major, Jon J.; East, Amy; O'connor, James; Grant, Gordon E.; Wilcox, Andrew C.; Magirl, Christopher S.; Collins, Matthias J.; Tullos, Desiree D.; Tsutsumi, Daizo; Laronne, Jonathan B.

    2017-01-01

    Recent decades have seen a marked increase in the number of dams removed in the United States. Investigations following a number of removals are beginning to inform how, and how fast, rivers and their ecosystems respond to released sediment. Though only a few tens of studies detail physical responses to removals, common findings have begun to emerge. They include: (1) Rivers are resilient and respond quickly to dam removals, especially when removals are sudden rather than prolonged. Rivers can swiftly evacuate large fractions of reservoir sediment (≥50% within one year), especially when sediment is coarse grained (sand and gravel). The channel downstream typically takes months to years—not decades—to achieve a degree of stability within its range of natural variability. (2) Modest streamflows (<2-year return interval flows) can erode and transport large amounts of reservoir sediment. Greater streamflows commonly are needed to access remnant reservoir sediment and transport it downstream. (3) Dam height, sediment volume, and sediment caliber strongly influence downstream response to dam removal. Removals of large dams (≥10 m tall) have had longer-lasting and more widespread downstream effects than more common removals of small dams. (4) Downstream valley morphology and position of a dam within a watershed influence the distribution of released sediment. Valley confinement, downstream channel gradient, locations and depths of channel pools, locations and geometries of extant channel bars, and locations of other reservoirs all influence the downstream fate of released sediment.

  7. Libby/Hungry Horse Dams Wildlife Mitigation : Montana Wildlife Habitat Protection : Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Marilyn

    1992-12-01

    The purpose of this project was to develop and obtain information necessary to evaluate and undertake specific wildlife habitat protection/enhancement actions in northwest Montana as outlined in the Columbia River Basin Fish and Wildlife Program. Three waterfowl projects were evaluated between September 1989 and June 1990. Weaver's Slough project involved the proposed acquisition of 200 acres of irrigated farmland and a donated conservation easement on an additional 213 acres. The proposal included enhancement of the agricultural lands by conversion to upland nesting cover. This project was rated the lowest priority based on limited potential for enhancement and no further action was pursued. The Crow Creek Ranch project involved the proposed acquisition of approximately 1830 acres of grazing and dryland farming lands. The intent would be to restore drained potholes and provide adjacent upland nesting cover to increase waterfowl production. This project received the highest rating based on the immediate threat of subdivision, the opportunity to restore degraded wetlands, and the overall benefits to numerous species besides waterfowl. Ducks Unlimited was not able to participate as a cooperator on this project due to the jurisdiction concerns between State and tribal ownership. The USFWS ultimately acquired 1,550 acres of this proposed project. No mitigation funds were used. The Ashley Creek project involved acquisition of 870 acres adjacent to the Smith Lake Waterfowl Production Area. The primary goal was to create approximately 470 acres of wetland habitat with dikes and subimpoundments. This project was rated second in priority due to the lesser threat of loss. A feasibility analysis was completed by Ducks Unlimited based on a concept design. Although adequate water was available for the project, soil testing indicated that the organic soils adjacent to the creek would not support the necessary dikes. The project was determined not feasible for mitigation

  8. An approach using ensemble empirical mode decomposition to remove noise from prototypical observations on dam safety.

    Science.gov (United States)

    Su, Huaizhi; Li, Hao; Chen, Zhexin; Wen, Zhiping

    2016-01-01

    It is very important for dam safety control to identify reasonably dam behavior according to the prototypical observations on deformation, seepage, stress, etc. However, there are many cases in which the noise corrupts the prototypical observations, and it must be removed from the data. Considering the nonlinear and non-stationary characteristics of data series with signal intermittency, an ensemble empirical mode decomposition (EEMD)-based method is presented to remove noise from prototypical observations on dam safety. Its basic principle and implementation process are discussed. The key parameters and rules, which can adapt the noise removal requirements of prototypical observations on dam safety, are given. The displacement of one actual dam is taken as an example. The noise removal capability of EEMD-based method is assessed. It is indicated that the dam displacement feature can be reflected more clearly by removing noise from prototypical observations on dam displacement. The statistical model, which is built according to noise-removed data series, can provide the more precise forecast for structural behavior.

  9. Rapid water quality change in the Elwha River estuary complex during dam removal

    Science.gov (United States)

    Foley, Melissa M.; Duda, Jeffrey J.; Beirne, Matthew M.; Paradis, Rebecca; Ritchie, Andrew; Warrick, Jonathan A.

    2015-01-01

    Dam removal in the United States is increasing as a result of structural concerns, sedimentation of reservoirs, and declining riverine ecosystem conditions. The removal of the 32 m Elwha and 64 m Glines Canyon dams from the Elwha River in Washington, U.S.A., was the largest dam removal project in North American history. During the 3 yr of dam removal—from September 2011 to August 2014—more than ten million cubic meters of sediment was eroded from the former reservoirs, transported downstream, and deposited throughout the lower river, river delta, and nearshore waters of the Strait of Juan de Fuca. Water quality data collected in the estuary complex at the mouth of the Elwha River document how conditions in the estuary changed as a result of sediment deposition over the 3 yr the dams were removed. Rapid and large-scale changes in estuary conditions—including salinity, depth, and turbidity—occurred 1 yr into the dam removal process. Tidal propagation into the estuary ceased following a large sediment deposition event that began in October 2013, resulting in decreased salinity, and increased depth and turbidity in the estuary complex. These changes have persisted in the system through dam removal, significantly altering the structure and functioning of the Elwha River estuary ecosystem.

  10. The effects of small dam removal on the distribution of sedimentary contaminants.

    Science.gov (United States)

    Ashley, Jeffrey T F; Bushaw-Newton, Karen; Wilhelm, Matt; Boettner, Adam; Drames, Gregg; Velinsky, David J

    2006-03-01

    With increasing concern over degradation of aquatic resources, issues of liability, and maintenance costs, removal of small dams has become increasing popular. Although the benefits of removal seem to outweigh the drawbacks, there is a relative paucity of studies documenting the extent and magnitude of biological and chemical changes associated with dam removal, especially those evaluating potential changes in contaminant inventories. In August and November of 2000, a run-of-the-river dam on Manatawny Creek (southeast Pennsylvania) was removed in a two-stage process. To assess the effects of dam removal on the contaminant redistribution within the creek, sedimentary concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace metals (Cd, Cr, Cu, Ni, Pb, Zn) were evaluated prior to and several months after removal. Pre- and post-removal analyses revealed elevated and spatially variable concentrations of total PAHs (ranging from approximately 200 to 81,000 ng(g dry weight) and low to moderate concentrations of trace metals and PCBs. The concentrations of these sedimentary contaminants pre- versus post-removal were not significantly different. Additionally, though the impoundment received storm water run-off and associated contaminants from the adjacent city of Pottstown, the total inventory of fine-grain sediments in the impoundment prior to removal was very low. The removal of the low-level Manatawny Creek dam did not significantly redistribute contaminants downstream. However, each dam removal should be assessed on a case by case basis where the potential of sedimentary contaminant redistribution upon dam removal exists.

  11. Seasonally distinct taxonomic and functional shifts in macroinvertebrate communities following dam removal

    Science.gov (United States)

    Manning, David W.P.

    2017-01-01

    Dam removal is an increasingly popular restoration tool, but our understanding of ecological responses to dam removal over time is still in the early stages. We quantified seasonal benthic macroinvertebrate density, taxonomic composition, and functional traits for three years after lowhead dam removal in three reaches of the Olentangy River (Ohio, USA): two upstream of former dam (one restored, one unrestored), and one downstream of former dam. Macroinvertebrate community density, generic richness, and Shannon–Wiener diversity decreased between ∼9 and ∼15 months after dam removal; all three variables consistently increased thereafter. These threshold responses were dependent on reach location: density and richness increased ∼15 months after removal in upstream reaches versus ∼19 months downstream of the former dam. Initial macroinvertebrate density declines were likely related to seasonality or life-history characteristics, but density increased up to 2.27× from year to year in three out of four seasons (late autumn, early spring, summer) across all reaches. Macroinvertebrate community composition was similar among the three reaches, but differed seasonally based on non-metric multidimensional scaling (NMDS) and analysis of similarity (ANOSIM). Seasonal differences among communities tended to decrease after dam removal. We detected community-wide shifts in functional traits such as multivoltinism, depositional habitat use, burrowing, and collector-gatherer feeding mode. We observed that these traits were expressed most strongly with Chironomidae, which was the most abundant family. Our results suggest that seasonal environmental conditions can play a role in the response and recovery of macroinvertebrate communities—often used to monitor ecosystem condition—following dam removal. In particular, macroinvertebrate density and diversity can show recovery after dam removal, especially in seasons when macroinvertebrate density is typically lowest, with

  12. Contaminant sampling to facilitate dam removals/habitat restoration in New England

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In a screening level survey of sediments impounded by New England dams that were being investigated for possible removal, only one of nine sites had contaminant...

  13. Sediment pollutant evaluation at priority dam removal sites in North Carolina

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — North Carolina dam removal mitigation guidelines call for site-specific evaluation of sediment issues, including sediment contamination. From 2004 to 2008, the U.S....

  14. The rapid return of marine-derived nutrients to a freshwater food web following dam removal

    Science.gov (United States)

    Tonra, Christopher M; Sager-Fradkin, Kimberly A.; Morley, Sarah A; Duda, Jeff; Marra, Peter P.

    2015-01-01

    Dam removal is increasingly being recognized as a viable river restoration action. Although the main beneficiaries of restored connectivity are often migratory fish populations, little is known regarding recovery of other parts of the freshwater food web, particularly terrestrial components. We measured stable isotopes in key components to the freshwater food web: salmon, freshwater macroinvertebrates and a river specialist bird, American dipper (Cinclus mexicanus), before and after removal of the Elwha Dam, WA, USA. Less than a year after dam removal, salmon returned to the system and released marine-derived nutrients (MDN). In that same year we documented an increase in stable-nitrogen and carbon isotope ratios in American dippers. These results indicate that MDN from anadromous fish, an important nutrient subsidy that crosses the aquatic–terrestrial boundary, can return rapidly to food webs after dams are removed which is an important component of ecosystem recovery.

  15. Geomorphic and ecological disturbance and recovery from two small dams and their removal.

    Science.gov (United States)

    Tullos, Desirée D; Finn, Debra S; Walter, Cara

    2014-01-01

    Dams are known to impact river channels and ecosystems, both during their lifetime and in their decommissioning. In this study, we applied a before-after-control-impact design associated with two small dam removals to investigate abiotic and biotic recovery trajectories from both the elimination of the press disturbance associated with the presence of dams and the introduction of a pulse disturbance associated with removal of dams. The two case studies represent different geomorphic and ecological conditions that we expected to represent low and high sensitivities to the pulse disturbance of dam removal: the 4 m tall, gravel-filled Brownsville Dam on the wadeable Calapooia River and the 12.5 m tall, sand and gravel-filled Savage Rapids Dam on the largely non-wadeable Rogue River. We evaluated both geomorphic and ecological responses annually for two years post removal, and asked if functional traits of the macroinvertebrate assemblages provided more persistent signals of ecological disturbance than taxonomically defined assemblages over the period of study. Results indicate that: 1) the presence of the dams constituted a strong ecological press disturbance to the near-downstream reaches on both rivers, despite the fact that both rivers passed unregulated flow and sediment during the high flow season; 2) ecological recovery from this press disturbance occurred within the year following the restoration action of dam removal, whereas signals of geomorphic disturbance from the pulse of released sediment persisted two years post-removal, and 3) the strength of the press disturbance and the rapid ecological recovery were detected regardless of whether recovery was assessed by taxonomic or functional assemblages and for both case studies, in spite of their different geomorphic settings.

  16. Geomorphic and ecological disturbance and recovery from two small dams and their removal.

    Directory of Open Access Journals (Sweden)

    Desirée D Tullos

    Full Text Available Dams are known to impact river channels and ecosystems, both during their lifetime and in their decommissioning. In this study, we applied a before-after-control-impact design associated with two small dam removals to investigate abiotic and biotic recovery trajectories from both the elimination of the press disturbance associated with the presence of dams and the introduction of a pulse disturbance associated with removal of dams. The two case studies represent different geomorphic and ecological conditions that we expected to represent low and high sensitivities to the pulse disturbance of dam removal: the 4 m tall, gravel-filled Brownsville Dam on the wadeable Calapooia River and the 12.5 m tall, sand and gravel-filled Savage Rapids Dam on the largely non-wadeable Rogue River. We evaluated both geomorphic and ecological responses annually for two years post removal, and asked if functional traits of the macroinvertebrate assemblages provided more persistent signals of ecological disturbance than taxonomically defined assemblages over the period of study. Results indicate that: 1 the presence of the dams constituted a strong ecological press disturbance to the near-downstream reaches on both rivers, despite the fact that both rivers passed unregulated flow and sediment during the high flow season; 2 ecological recovery from this press disturbance occurred within the year following the restoration action of dam removal, whereas signals of geomorphic disturbance from the pulse of released sediment persisted two years post-removal, and 3 the strength of the press disturbance and the rapid ecological recovery were detected regardless of whether recovery was assessed by taxonomic or functional assemblages and for both case studies, in spite of their different geomorphic settings.

  17. Sedimentology of new fluvial deposits on the Elwha River, Washington, USA, formed during large-scale dam removal

    Science.gov (United States)

    Draut, Amy; Ritchie, Andrew C.

    2015-01-01

    Removal of two dams 32 m and 64 m high on the Elwha River, Washington, USA, provided the first opportunity to examine river response to a dam removal and controlled sediment influx on such a large scale. Although many recent river-restoration efforts have included dam removal, large dam removals have been rare enough that their physical and ecological effects remain poorly understood. New sedimentary deposits that formed during this multi-stage dam removal result from a unique, artificially created imbalance between fluvial sediment supply and transport capacity. River flows during dam removal were essentially natural and included no large floods in the first two years, while draining of the two reservoirs greatly increased the sediment supply available for fluvial transport. The resulting sedimentary deposits exhibited substantial spatial heterogeneity in thickness, stratal-formation patterns, grain size and organic content. Initial mud deposition in the first year of dam removal filled pore spaces in the pre-dam-removal cobble bed, potentially causing ecological disturbance but not aggrading the bed substantially at first. During the second winter of dam removal, thicker and in some cases coarser deposits replaced the early mud deposits. By 18 months into dam removal, channel-margin and floodplain deposits were commonly >0.5 m thick and, contrary to pre-dam-removal predictions that silt and clay would bypass the river system, included average mud content around 20%. Large wood and lenses of smaller organic particles were common in the new deposits, presumably contributing additional carbon and nutrients to the ecosystem downstream of the dam sites. Understanding initial sedimentary response to the Elwha River dam removals will inform subsequent analyses of longer-term sedimentary, geomorphic and ecosystem changes in this fluvial and coastal system, and will provide important lessons for other river-restoration efforts where large dam removal is planned or

  18. Geomorphic monitoring of two dam removals in northern Iberian Peninsula: methodology, results and lessons learned

    Science.gov (United States)

    Ibisate, Askoa; Ollero, Alfredo; Ballarín, Daniel; Horacio, Jesús; Mora, Daniel; Mesanza, Amaia; Ferrer-Boix, Carles; Acín, Vanesa; Granado, David; Martín-Vide, Juan Pedro

    2017-04-01

    The methodology and results of two dam removals in two different rivers is presented and compared. One removed all-at-once and the second one in a four-stage removal process. Methodology included topographical measurements of the channel, TLS measurements of river bed and bars and sediment grain size and transport. Morphological channel adjustments occurred mainly shortly after dam removals, but with differences among the one removed instantaneously, that was immediate, whereas that conducted by stages that took longer. Degradational processes were observed upstream of both dams, but also aggradational processes (pool filling) upstream of one of them. Flood events reactivated incision and bank erosion, whereas longitudinal profile recovery, grain-size sorting and upstream erosion took longer, especially in that removed in stages, where one year after is total removal its maximum potential erosion attained just the closest reach to the dam and knickpoint upstream migration was still adapting to the new base level position. Lessons learned helped to improve a third in process dam removal geomorphological monitoring, including an improved sediment transport and bank retreat monitoring.

  19. Importance of Field Data for Numerical Modeling to Dam Removal on a Mountain Channel

    Science.gov (United States)

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

    2015-12-01

    In 2011, a 13-m high Chijiawan Dam on Chijiawan Creek was removed due to the safety concern due to aging structure and scoured dam foundation as well as habitat restoration of the endangered Formosan landlocked salmon. Similar to Chijiawan Dam, many dams in Taiwan are located in steep mountainous area with coarser sediment and high sediment yield, and may be removed in the near future. Since the capability of current sediment transport model is insufficient, a systematic planning of field survey and monitoring work can effectively help to decrease data uncertainty in simulation. In this study, we aimed to understand the minimum requirements of data for numerical model to predict channel responses after dam removal, according to the data of pre-project and long term post-project monitoring works from removal of Chijiawan dam. We collected the hourly discharge data of Taipower gaging station located 6.8 km from the dam from 2010 to 2012 and conducted surveys of grain size distributions, cross-sectional and longitudinal profiles. We applied Sedimentation and River Hydraulics (SRH) one-dimensional model to simulate bed elevation changes by different setting of data input, including bed sediment, roughness coefficient, cross-section spacing, and flow discharge. Then, we performed a sensitivity analysis by using Root Mean Square Error (RMSE) to evaluate the minimum requirements of data for predicting to dam removal. The RMSE variability of varied setting of bed sediment, roughness coefficient, cross-section spacing, and flow discharge ranged from 0.02 m, 0.17 m, 0.14 m and 0.09 m, respectively. The results highlight that the simulation is sensitive to roughness coefficient, cross-section spacing, and flow discharge, and less sensitive to bed sediment. We anticipate the results will help decision maker to understand the importance of field data in future removals.

  20. Anadromous sea lampreys recolonize a Maine coastal river tributary after dam removal

    Science.gov (United States)

    Hogg, Robert; Coghlan Jr., Stephen M.; Zydlewski, Joseph

    2013-01-01

    Sedgeunkedunk Stream, a third-order tributary to the Penobscot River, Maine, historically supported several anadromous fishes, including the Atlantic Salmon Salmo salar, AlewifeAlosa pseudoharengus, and Sea Lamprey Petromyzon marinus. However, two small dams constructed in the 1800s reduced or eliminated spawning runs entirely. In 2009, efforts to restore marine–freshwater connectivity in the system culminated with removal of the lowermost dam, thus providing access to an additional 4.6 km of lotic habitat. Because Sea Lampreys utilized accessible habitat prior to dam removal, they were chosen as a focal species with which to quantify recolonization. During spawning runs of 2008–2011 (before and after dam removal), individuals were marked with PIT tags and their activity was tracked with daily recapture surveys. Open-population mark–recapture models indicated a fourfold increase in the annual abundance of spawning-phase Sea Lampreys, with estimates rising from 59±4 () before dam removal (2008) to 223±18 and 242±16 after dam removal (2010 and 2011, respectively). Accompanying the marked increase in annual abundance was a greater than fourfold increase in nesting sites: the number of nests increased from 31 in 2008 to 128 and 131 in 2010 and 2011, respectively. During the initial recolonization event (i.e., in 2010), Sea Lampreys took 6 d to move past the former dam site and 9 d to expand into the furthest upstream reaches. Conversely, during the 2011 spawning run, Sea Lampreys took only 3 d to penetrate into the upstream reaches, thus suggesting a potential positive feedback in which larval recruitment into the system may have attracted adult spawners via conspecific pheromone cues. Although more research is needed to verify the migratory pheromone hypothesis, our study clearly demonstrates that small-stream dam removal in coastal river systems has the potential to enhance recovery of declining anadromous fish populations.

  1. The Influence of Ground Water on Stream Restoration Following Dam Removal

    Science.gov (United States)

    Constantz, J.; Essaid, H.

    2003-12-01

    With the exception of ground-water seepage beneath dams and the resulting impact on structural failure, there is a void of work directly examining the downstream impacts of dams from the perspective of ground-water/surface-water interaction. This work considers alterations in an alluvial basin caused by: (1) erection of a dam upstream, (2) followed by ground-water pumping in the basin, and (3) dam removal. Theoretical results predict that when dams are removed in developed ground-water basins, downstream baseflows may be greatly reduced relative to natural baseflows, as a result of lower water table elevations in the developed basin relative to the natural setting. Without the dam as a `safety valve' providing extra streamflow during low-flow seasons, there is a real potential for ephemeral conditions downstream of the previous location of the dam as the dry season progresses. MODFLOW simulations are used to test these theoretical results, by quantifying the impact of dam removal on downstream surface water and ground water. The simulations incorporate an improved stream-aquifer interaction and streamflow routing package to represent movement of water in the vadose zone between the stream and a lowered water table. An idealized MODFLOW model with the new stream package has been constructed, which extends from the upland bedrock headwaters of a stream to the downstream sediment-filled basin. The model domain is 180 km long, 15 km wide, and 2.2 km deep, including a stream with a potential length of 180 km. In the upper reaches, the stream is divided into a north, south, and main stem with their confluence upstream of a dam situated in the domain above the bedrock/basin contact. Horizontal discretization is 1000 m in the direction parallel to the stream, 200 to 600 m perpendicular to the stream, and vertical discretization is 100 m. This modeling framework affords the opportunity to examine a variety of cases with and without the presence of an upstream dam. Initial

  2. Economic Efficiency and Equity in Dams Removal: Case studies in Northeastern Massachusetts Doina Oglavie, Ellen Douglas, David Terkla

    Science.gov (United States)

    Oglavie, D. R.; Douglas, E. M.; Terkla, D.

    2009-12-01

    According to American Rivers (www.americanrivers.org), Massachusetts has almost 3,000 dams under state regulation, 296 of which have been classified as high hazard, meaning they pose a serious threat to human life if they should fail. Most of these dams, however, are low head, “run-of-the-river” dams that no longer serve the purpose for which they were built. The presence of these dams has fragmented aquatic and riparian ecosystems, impeded fish passage and generally impacted the natural ecological and hydrological functioning of the streams in which they reside. Dam removal should be considered when a dam no longer serves its function. Although in many cases, the removal of a dam is environmentally beneficial (at least over the long term), sometimes the removal of a dam can incur environmental costs, such as release of contaminants that were sequestered behind the dam. Dam removal is a complex issue especially with respect to privately owned dams. In many cases, dam removal is less costly than dam maintenance or upgrade, hence dam removal decisions tend to be based on purely monetary considerations, and the environmental costs or benefits associated with the dam are not considered. Typically, the main objective for the dam owner is to incur the lowest possible cost (private cost), whether it be operating and maintenance or removal; external costs (environmental degradation) are rarely, if ever, considered, hence the true cost to society is not included in the economic analysis. If dam operation and removal decisions are to be economically efficient, then they have to include both the private costs as well as the external (environmental) costs. The purpose of this work is to 1) attempt to quantify the externalities associated with the maintenance and the removal of dams, 2) assess whether or not the current dam removal evaluation process maximizes social welfare (efficiency and equity) and 3) suggest ways in which this process can be improved by including the

  3. The Scientific and Institutional Context for the Removal of Marmot Dam, Sandy River, Oregon

    Science.gov (United States)

    Grant, G. E.; Major, J. J.; O'Connor, J.; Wallick, J. R.; Marr, J.; Wilcock, P.; Podolack, C.

    2008-12-01

    Dam removal has been widely viewed as an important river restoration strategy and an interesting scientific opportunity, the latter because it represents a real-time, full-scale field experiment on fluvial adjustment. Removals therefore offer an excellent setting for testing analytical models of sediment transport, morphologic change, and our capacity to predict short- and medium-term channel evolution in response to changing water and sediment transport regimes. Most dam removals to date have involved relatively small structures and modest releases of sediment stored in pre-removal reservoirs. The largest instantaneous and uncontrolled release of sediment accompanying a dam removal occurred with the breaching of the Marmot coffer dam on the Sandy River in Oregon in October 2007. Marmot Dam was a 14-m-high by 50-m-wide diversion dam built in 1913 as part of a larger hydroelectric project. It was located on the Sandy River, an energetic gravel to cobble-bed river that naturally carries copious quantities of sand and gravel, ~45 km upstream from its confluence with the Columbia River near Portland, Oregon. At the time of removal, the reservoir upstream of the dam was completely filled with ~750,000 m3 of sand (40%) and gravel (60%). The river below the dam includes bedrock gorges, mixed bedrock/alluvial reaches, and alluvial reaches with well-developed gravel and sand bars. The decision to remove the dam was motivated by a combination of increasing maintenance costs and an unfavorable future economic return due to the necessity of installing expensive fish passage facilities to meet relicensing requirements. Portland General Electric, the dam's owner, surrendered the dam's license in 1999, and removal commenced in summer 2007. To remove the concrete structure, a temporary coffer dam was constructed 70 m upstream. In October 2007 the coffer dam was breached and the river allowed to erode the remaining impounded sediment (~730,000 m3). Physical modeling conducted at

  4. Summary and anticipated responses to Elwha River dam removal: Chapter 9 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Gelfenbaum, Guy; Duda, Jeffrey J.; Warrick, Jonathan A.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    Starting in September 2011, the removal of two large dams on the Elwha River will begin an unprecedented river restoration project because of the size of the dams, the volume of sediment released, the pristine watershed upstream of the dam sites, and the potential for renewing salmon populations. Ecosystem studies of the Elwha watershed indicate that the effects of almost 100 years of damming are measurable and of consequence. These effects include smaller spawning salmon populations, massive sediment retention behind the dams, coarsening of the riverbed downstream of the dams, low nutrient concentrations in the river waters, and coastal erosion that has accelerated markedly with time. During

  5. A river might run through it again: criteria for consideration of dam removal and interim lessons from California.

    Science.gov (United States)

    Pejchar, L; Warner, K

    2001-11-01

    Resource managers are increasingly being challenged by stakeholder groups to consider dam removal as a policy option and as a tool for watershed management. As more dam owners face high maintenance costs, and rivers as spawning grounds for anadromous fish become increasingly valuable, dam removal may provide the greatest net benefit to society. This article reviews the impact of Endangered Species Act listings for anadromous fish and recent shifts in the Federal Energy Regulatory Commission's hydropower benefit-costs analysis and discusses their implications for dam removal in California. We propose evaluative criteria for consideration of dam removal and apply them to two case studies: the Daguerre and Englebright Dams on the Yuba River and the Scott and Van Horne Dams on the South Eel River, California.

  6. How stakeholders frame dam removal: The role of current and anticipated future ecosystem service use

    Science.gov (United States)

    Reilly, Kate; Adamowski, Jan

    2016-04-01

    Many river restoration projects, including dam removal, are controversial and can trigger conflicts between stakeholders who are for and against the proposed project. The study of environmental conflicts suggests that differences in how stakeholders 'frame', or make sense of a situation based on their prior knowledge and experiences, can perpetuate conflicts. Understanding different stakeholders' frames, particularly how they converge, can form the basis of successful conflict resolution. In the case of dam removals, it is often assumed that emphasising increased provision of ecosystem services can be a point of convergence between those advocating for ecological restoration and those opposed to removal because of negative human impacts. However, how exactly stakeholders frame a contentious proposed dam removal and how those frames relate to ecosystem services has been little studied. Here we used the case of a potential dam removal in New Brunswick to investigate how people frame the issue and how that relates to their current and anticipated future use of ecosystem services. Based on in-depth interviews with 30 stakeholders in the area, including both people for and against dam removal, we found that both groups currently used ecosystem services and were in favour of ecosystem protection. However, they differed in how they framed the issue of the potential dam removal. The group against dam removal framed the issue as one of loss and risk - they thought that any potential benefits to the ecosystem would be outweighed by the high risk of negative social impacts caused by a loss of access to ecosystem services, such as recreation and aesthetic enjoyment. By contrast, the group in favour of the dam framed the issue as one of opportunity and justice. They thought that following a short transition period, all stakeholders would benefit from the restored river, particularly from a restored salmon fishery, improved aesthetic appeal and the long-term sustainability of an

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

    Science.gov (United States)

    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

  8. PREDICTING THE DEPTH OF EROSION IN RESERVOIRS FOLLOWING DAM REMOVAL USING BANK STABILITY ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    Martin W. DOYLE; Emily H. STANLEY; Andy R. SELLE; John M. STOFLETH; Jon M. HARBOR

    2003-01-01

    Dam removal has emerged in the U.S. as a critical concern for river management. Of particular interest is predicting the quantity of sediment that will be eroded from a reservoir following dam removal, which necessitates predicting the geometry a channel will approach as it forms in the reservoir. The geometry and sediment characteristics of the Koshkonong River were measured as it adjusted to the removal of the Rockdale Dam. Bank stability modeling was used as a tool for predicting the maximum depth of the evolving channel and general agreement was found between depths predicted with the model and those observed up to one year following dam removal. Model sensitivity analysis showed strong control of bank heights by groundwater levels in the reservoir sediment, as well as some control by vegetation established on the sediment surface. Long-term monitoring is needed to assess the accuracy of the model, but preliminary agreement is encouraging for applying this model and similar models to future dam removals.

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

    Science.gov (United States)

    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).

  10. Fish community response to dam removal in a Maine coastal river tributary

    Science.gov (United States)

    Zydlewski, Joseph; Hogg, Robert S.; Coghlan Jr., Stephen M.; Gardner, Cory

    2016-01-01

    Sedgeunkedunk Stream, a third-order tributary to the Penobscot River in Maine, historically has supported several anadromous fishes including Atlantic Salmon Salmo salar, Alewife Alosa pseudoharengus, and Sea Lamprey Petromyzon marinus. Two small dams constructed in the 1800s reduced or eliminated spawning runs entirely. In 2009, efforts to restore marine–freshwater connectivity in the system culminated in removal of the lowermost dam (Mill Dam) providing access to 4.7 km of lotic habitat and unimpeded passage into the lentic habitat of Fields Pond. In anticipation of these barrier removals, we initiated a modified before-after-control-impact study, and monitored stream fish assemblages in fixed treatment and reference sites. Electrofishing surveys were conducted twice yearly since 2007. Results indicated that density, biomass, and diversity of the fish assemblage increased at all treatment sites upstream of the 2009 dam removal. No distinct changes in these metrics occurred at reference sites. We documented recolonization and successful reproduction of Atlantic Salmon, Alewife, and Sea Lamprey in previously inaccessible upstream reaches. These results clearly demonstrate that dam removal has enhanced the fish assemblage by providing an undisrupted stream gradient linking a small headwater lake and tributary with a large coastal river, its estuary, and the Atlantic Ocean.

  11. Predicting the thermal effects of dam removal on the Klamath River.

    Science.gov (United States)

    Bartholow, John M; Campbell, Sharon G; Flug, Marshall

    2004-12-01

    The Klamath River once supported large runs of anadromous salmonids. Water temperature associated with multiple mainstem hydropower facilities might be one of many factors responsible for depressing Klamath salmon stocks. We combined a water quantity model and a water quality model to predict how removing the series of dams below Upper Klamath Lake might affect water temperatures, and ultimately fish survival, in the spawning and rearing portions of the mainstem Klamath. We calibrated the water quantity and quality models and applied them for the hydrometeorological conditions during a 40-year postdam period. Then, we hypothetically removed the dams and their impoundments from the models and reestimated the river's water temperatures. The principal thermal effect of dam and reservoir removal would be to restore the timing (phase) of the river's seasonal thermal signature by shifting it approximately 18 days earlier in the year, resulting in river temperatures that more rapidly track ambient air temperatures. Such a shift would likely cool thermal habitat conditions for adult fall chinook (Oncorhynchus tshawytscha) during upstream migration and benefit mainstem spawning. By contrast, spring and early summer temperatures could be warmer without dams, potentially harming chinook rearing and outmigration in the mainstem. Dam removal might affect the river's thermal regime during certain conditions for over 200 km of the mainstem.

  12. Using hydraulic modeling to address social impacts of small dam removals in southern New Jersey.

    Science.gov (United States)

    Wyrick, Joshua R; Rischman, Brian A; Burke, Christopher A; McGee, Craig; Williams, Chasity

    2009-07-01

    Small relic mill dams are common in the watersheds of southern New Jersey, dotting the landscape with many small neighborhood lakes. Originally built in the late 1800s, most of these dams have become increasingly unable to handle current design storms due to increased urbanization of the watersheds. Several of these dams have also been classified as "high hazard" by the New Jersey Department of Environmental Protection Dam Safety Division because their failure has the potential for loss of life or extensive property damage. The current private owners are generally unable to afford the high repair costs needed to rehabilitate the dams to current safety standards, and are therefore more inclined to remove them. This research analyses both the physical and social impacts of the removal of two small dams in southern New Jersey, and integrates the two seemingly disparate concepts. Using hydraulic modeling and previous case studies, it is predicted that there will be limited effects to the hydrological and biological characteristics of the stream corridor. A survey distributed to the affected homeowners that live on these lakes shows that the community, however, expects significant impacts to the bio-physical characteristics of the stream corridor, as well financial impacts to their property value and social impacts to their recreational activities. The current study exposes the widening gap between policy makers and landowners, and highlights where complete stakeholder interaction could and should occur.

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

    Science.gov (United States)

    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

  14. Optimizing multiple dam removals under multiple objectives: Linking tributary habitat and the Lake Erie ecosystem

    Science.gov (United States)

    Zheng, Pearl Q.; Hobbs, Benjamin F.; Koonce, Joseph F.

    2009-12-01

    A model is proposed for optimizing the net benefits of removing multiple dams in U.S. watersheds of Lake Erie by quantifying impacts upon social, ecological, and economic objectives of importance to managers and stakeholders. Explicit consideration is given to the linkages between newly accessible tributary habitat and the lake's ecosystem. The model is a mixed integer linear program (MILP) that selects a portfolio of potential dam removals that could achieve the best possible value of a weighted sum of the objective(s), while still satisfying the constraints. Using response functions extracted from the Lake Erie Ecological Model and an empirical cost model, the MILP accounts for ecological and economic effects of habitat changes for both desirable native walleye and undesirable sea lamprey. The solutions show the effect on removal decisions of alternative prioritizations among cost and environmental objectives and the resulting trade-offs among those objectives. The MILP can be used as a screening model to identify portfolios of dam removals that are potentially cost-effective enhancements of habitat and the Lake Erie ecosystem; subsequent site-specific studies would be needed prior to actually removing dams.

  15. Evaluation of the Biological Effects of the Northwest Power Conservation Council's Mainstem Amendment on the Fisheries Upstream and Downstream of Libby Dam, Montana, 2007-2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester, Ryan; Stephens, Brian; Tohtz, Joel [Montana Fish, Wildlife & Parks

    2009-04-03

    A new project began in 2005 to monitor the biological and physical effects of improved operations of Hungry Horse and Libby Dams, Montana, called for by the Northwest Power and Conservation Council (NPCC) Mainstem Amendment. This operating strategy was designed to benefit resident fish impacted by hydropower and flood control operations. Under the new operating guidelines, July through September reservoir drafts will be limited to 10 feet from full pool during the highest 80% of water supply years and 20 feet from full pool during the lowest 20% of water supply (drought) years. Limits were also established on how rapidly discharge from the dams can be increased or decreased depending on the season. The NPCC also directed the federal agencies that operate Libby and Hungry Horse Dams to implement a new flood control strategy (VARQ) and directed Montana Fish, Wildlife & Parks to evaluate biological responses to this operating strategy. The Mainstem Amendment operating strategy has not been fully implemented at the Montana dams as of June 2008 but the strategy will be implemented in 2009. This report highlights the monitoring methods used to monitor the effects of the Mainstem Amendment operations on fishes, habitat, and aquatic invertebrates upstream and downstream of Libby Dam. We also present initial assessments of data and the effects of various operating strategies on physical and biological components of the systems upstream and downstream of Libby Dam. Annual electrofishing surveys in the Kootenai River and selected tributaries, along with gill net surveys in the reservoir, are being used to quantify the impacts of dam operations on fish populations upstream and downstream of Libby Dam. Scales and otoliths are being used to determine the age structure and growth of focal species. Annual population estimates and tagging experiments provide estimates of survival and growth in the mainstem Kootenai River and selected tributaries. Radio telemetry will be used to

  16. Fish community dynamics following dam removal in a fragmented agricultural stream

    Science.gov (United States)

    Kornis, Matthew; Weidel, Brian C.; Powers, Stephens; Diebel, Matthew W.; Cline, Timpthy; Fox, Justin; Kitchell, James F.

    2014-01-01

    Habitat fragmentation impedes dispersal of aquatic fauna, and barrier removal is increasingly used to increase stream network connectivity and facilitate fish dispersal. Improved understanding of fish community response to barrier removal is needed, especially in fragmented agricultural streams where numerous antiquated dams are likely destined for removal. We examined post-removal responses in two distinct fish communities formerly separated by a small aging mill dam. The dam was removed midway through the 6 year study, enabling passage for downstream fishes affiliated with a connected reservoir into previously inaccessible habitat, thus creating the potential for taxonomic homogenization between upstream and downstream communities. Both communities changed substantially post-removal. Two previously excluded species (white sucker, yellow perch) established substantial populations upstream of the former dam, contributing to a doubling of total fish biomass. Meanwhile, numerical density of pre-existing upstream fishes declined. Downstream, largemouth bass density was inversely correlated with prey fish density throughout the study, while post-removal declines in bluegill density coincided with cooler water temperature and increased suspended and benthic fine sediment. Upstream and downstream fish communities became more similar post-removal, represented by a shift in Bray-Curtis index from 14 to 41 % similarity. Our findings emphasize that barrier removal in highly fragmented stream networks can facilitate the unintended and possibly undesirable spread of species into headwater streams, including dispersal of species from remaining reservoirs. We suggest that knowledge of dispersal patterns for key piscivore and competitor species in both the target system and neighboring systems may help predict community outcomes following barrier removal.

  17. Quantifying Channel Morphology Changes in Response to the Removal of the Glines Canyon Dam, Elwha River, Washington

    Science.gov (United States)

    Free, B. J.; Ely, L. L.; Hickey, R.; Flake, R.; Baumgartner, S.

    2014-12-01

    The removal of two dams on the Elwha River, Washington, is the largest dam-removal project in history. Our research documents the sediment deposition, erosion, and channel changes between the dams following the initial sediment release from the removal of the upstream Glines Canyon Dam. Within the first year following the dam removal, the pulse of coarse sediment and large woody debris propagated downstream well over 6 km below the dam. The sediment deposition and altered channel hydraulics caused lateral channel migration where anabranching channels merge around new mid-channel bars and at large bends in the river channel. Documenting the river channel response to this exceptional sediment pulse could improve models of the impacts of future dam removals on similar gravel-bed rivers. We quantified the sediment flux and channel changes at four field sites 2-6 km downstream of Glines Canyon Dam. Topographic changes were surveyed with a terrestrial laser scanner (TLS) on an annual basis from August 2012 - August 2014 and the surface sediment distribution was quantified with bimonthly sediment counts. Differencing the annual TLS data yielded an overall increase in sediment throughout the study reach, with a minimum of 20,000 m3 of deposition on bars and banks exposed above the water surface in each 700-m-long TLS survey reach. The surface sediment distribution decreased from ~18 cm to dam removal began to re-emerge due to the remobilizing of sediment through the system.

  18. Assessing Changes to Organic Contaminant Fluxes from Contaminated Sediments Following Dam Removal in an Urbanized River

    Science.gov (United States)

    Restoration of rivers and their associated ecosystems is a growing priority for government agencies (e.g., NOAA, USDA), as well as conservation organizations. Dam removal is a major component of many restoration projects credited with reintroducing fish species, improving water ...

  19. Simulation of sediment transport due to dam removal and control of morphological changes

    Science.gov (United States)

    This paper presents two case studies of post dam removal sedimentation in the United States. Two different one-dimensional channel evolution simulation models were used: CCHE1D and CONCEPTS, respectively. The first case is the application of CCHE1D to assess the long-term (up to 10 years) morphologi...

  20. Assessing Organic Contaminant Fluxes from Contaminated Sediments Following Dam Removal in an Urbanized River

    Science.gov (United States)

    In this study, methods and approaches were developed and tested to assess changes in contaminant fluxes resulting from dam removal in a riverine system. Sediment traps and passive samplers were deployed to measure particulate and dissolved PAHs and PCBs in the water column prior...

  1. Assessing Changes in Contaminant Fluxes Following Dam Removal in an Urbanized River

    Science.gov (United States)

    Restoration of rivers and their associated ecosystems is a growing priority for government agencies (e.g., NOAA, USEPA), as well as conservation organizations. Dam removal is a major component of many restoration projects credited with reintroducing fish species, improving water...

  2. Monitoring Changes in Contaminant Fluxes Resulting from Dam Removal in an Urbanized River.

    Science.gov (United States)

    Restoration of rivers and their associated ecosystems is a growing priority for government agencies (e.g., NOAA, USEPA), as well as conservation organizations. Dam removal is a major component of many restoration projects credited with reintroducing fish species, improving water...

  3. Monitoring Organic Contaminant Fluxes Following Dam Removal Utilizing Passive Sampler Technology

    Science.gov (United States)

    Restoration of riverine habitats and their associated ecosystems is a growing priority for government agencies (e.g., USEPA, NOAA, USDA), as well as non-profit conservation organizations (e.g., American Rivers). Dam removal is a major component of many restoration projects credi...

  4. 77 FR 56189 - Proposed Information Collection; Comment Request; Elwha River Dam Removal and Floodplain...

    Science.gov (United States)

    2012-09-12

    ... pilot survey would be administered in two waves. In the first wave, Knowledge Networks (KN) would... River Dam Removal and Floodplain Restoration Ecosystem Service Valuation Pilot Project AGENCY: National... Conservation are requesting approval for a new information collection to conduct a pilot study to test the...

  5. Influence of groundwater pumping on streamflow restoration following upstream dam removal

    Science.gov (United States)

    Constantz, J.; Essaid, H.

    2007-01-01

    We compared streamflow in basins under the combined impacts of an upland dam and groundwater pumping withdrawals, by examining streamflow in the presence and absence of each impact. As a qualitative analysis, inter-watersbed streamflow comparisons were performed for several rivers flowing into the east side of the Central Valley, CA. Results suggest that, in the absence of upland dams supporting large reservoirs, some reaches of these rivers might develop ephemeral streamflow in late summer. As a quantitative analysis, we conducted a series of streamflow/ groundwater simulations (using MODFLOW-2000 plus the streamflow routing package, SFR1) for a representative hypothetical watershed, with an upland dam and groundwater pumping in the downstream basin, under humid, semi-arid, and and conditions. As a result of including the impact of groundwater pumping, post-dam removal simulated streamflow was significantly less than natural streamflow. The model predicts extensive ephemeral conditions in the basin during September for both the arid and semi-arid cases. The model predicts continued perennial conditions in the humid case, but spatially weighted, average streamflow of only 71% of natural September streamflow, as a result of continued pumping after dam removal.

  6. Early vegetation development on an exposed reservoir: implications for dam removal.

    Science.gov (United States)

    Auble, Gregor T; Shafroth, Patrick B; Scott, Michael L; Roelle, James E

    2007-06-01

    The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition.

  7. Coastal and lower Elwha River, Washington, prior to dam removal--history, status, and defining characteristics: Chapter 1 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    Characterizing the physical and biological characteristics of the lower Elwha River, its estuary, and adjacent nearshore habitats prior to dam removal is essential to monitor changes to these areas during and following the historic dam-removal project set to begin in September 2011. Based on the size of the two hydroelectric projects and the amount of sediment that will be released, the Elwha River in Washington State will be home to the largest river restoration through dam removal attempted in the United States. Built in 1912 and 1927, respectively, the Elwha and Glines Canyon Dams have altered key physical and biological characteristics of the Elwha River. Once abundant salmon populations, consisting of all five species of Pacific salmon, are restricted to the lower 7.8 river kilometers downstream of Elwha Dam and are currently in low numbers. Dam removal will reopen access to more than 140 km of mainstem, flood plain, and tributary habitat, most of which is protected within Olympic National Park. The high capture rate of river-borne sediments by the two reservoirs has changed the geomorphology of the riverbed downstream of the dams. Mobilization and downstream transport of these accumulated reservoir sediments during and following dam removal will significantly change downstream river reaches, the estuary complex, and the nearshore environment. To introduce the more detailed studies that follow in this report, we summarize many of the key aspects of the Elwha River ecosystem including a regional and historical context for this unprecedented project.

  8. Large-scale dam removal on the Elwha River, Washington, USA: Coastal geomorphic change

    Science.gov (United States)

    Gelfenbaum, Guy; Stevens, Andrew W.; Miller, Ian; Warrick, Jonathan A.; Ogston, Andrea S.; Eidam, Emily

    2015-10-01

    Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of mud, sand, and gravel since 1927, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams, initiated in September 2011, induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the geomorphic response of a coastal delta to these increases. Detailed measurements of beach topography and nearshore bathymetry show that 2.5 million m3 of sediment was deposited during the first two years of dam removal, which is 100 times greater than deposition rates measured prior to dam removal. The majority of the deposit was located in the intertidal and shallow subtidal region immediately offshore of the river mouth and was composed of sand and gravel. Additional areas of deposition include a secondary sandy deposit to the east of the river mouth and a muddy deposit west of the mouth. A comparison with fluvial sediment fluxes suggests that 70% of the sand and gravel and 6% of the mud supplied by the river was found in the survey area (within about 2 km of the mouth). A hydrodynamic and sediment transport model, validated with in-situ measurements, shows that tidal currents interacting with the larger relict submarine delta help disperse fine sediment large distances east and west of the river mouth. The model also suggests that waves and currents erode the primary deposit located near the river mouth and transport sandy sediment eastward to form the secondary deposit. Though most of the substrate of the larger relict submarine delta was unchanged during the first two years of dam removal, portions of the seafloor close to the river mouth became finer, modifying habitats for biological communities. These results show that river restoration, like natural changes in river sediment supply, can result in rapid and substantial coastal geomorphological responses.

  9. Occupancy patterns of mammals and lentic amphibians in the Elwha River riparian zone before dam removal

    Science.gov (United States)

    Jenkins, Kurt J.; Chelgren, Nathan; Sager-Fradkin, K.A.; Happe, P.J.; Adams, Michael J.

    2015-01-01

    The downstream transport of sediments and organics and upstream migration of anadromous fishes are key ecological processes in unregulated riverine ecosystems of the North Pacific coast, but their influence on wildlife habitats and populations is poorly documented. Removal of two large hydroelectric dams in Washington’s Elwha Valley provides an unprecedented opportunity to study long-term responses of wildlife populations to dam removal and restoration of these key ecological processes. We compared pre-dam removal patterns in the relative abundance and occupancy of mesocarnivores, small mammals and lentic amphibians of the Elwha River riparian zone above, between and below the dams. Occupancy of riparian habitats by three mesocarnivore species diminished upriver but did not appear to be closely linked with the absence of salmon in the upper river. Although the importance of salmon in the lower river cannot be discounted, other gradients in food resources also likely contributed to observed distribution patterns of mesocarnivores. Abundance and occupancy patterns within congeneric pairs of new world mice (Peromyscus spp.) and shrews (Sorex spp.) indicated that closely related species were negatively associated with each other and responded to habitat gradients in the riparian zone. The availability of lentic habitats of amphibians was highly variable, and occupancy was low as a result of rapidly changing flows during the larval development period. We speculate that long-term changes in habitat conditions and salmon availability following dam removal will elicit long-term changes in distribution of mesocarnivores, small mammals and amphibians. Long-term monitoring will enhance understanding of the role of fish and restored ecosystem processes on wildlife communities along salmon-bearing rivers in the region.

  10. Large-scale dam removal on the Elwha River, Washington, USA: Erosion of reservoir sediment

    Science.gov (United States)

    Randle, Timothy J.; Bountry, Jennifer A.; Ritchie, Andrew; Wille, Kurt

    2015-10-01

    Base-level lowering of reservoirs impounding upstream sediment supply triggers a series of channel evolution steps such as degradation, lateral erosion, and redeposition that can dramatically alter the reservoir landscape and decouple the relationship between stream power and sediment supply. Many case studies exist for small dam removals with a few years of sediment storage or dam breaches triggering instantaneous large sediment releases. However, quantitative information for a controlled drawdown initiating erosion of a large sediment deposit is rare. We investigate reservoir sediment response to the phased and concurrent drawdown of two reservoirs on the Elwha River, Washington, USA, during the largest dam removal in history by measuring changes in reservoir topography and channel morphology as a function of base-level lowering, river discharge, and cohesion. After two years, the Elwha Dam was completely removed, and three-quarters of Glines Canyon Dam were removed. Reservoir drawdown increments of 3 to 5 m were sufficient to initiate channel degradation and delta progradation across the width of the receding reservoir, redistributing decades of accumulated delta sediment throughout the reservoir while the lake still remained. The first year of dam removal resulted in up to 5 m of incision through the Lake Aldwell delta down to the predam surface and in just over 20 m of incision through the Lake Mills delta. In contrast, delta progradation resulted in a few meters of deposition in Lake Aldwell and 2 to 10 m in Lake Mills on top of prodelta and lakebed deposits. In coarse, noncohesive sediment, a braided channel developed and widened up to tenfold across the entire width of the reservoir. The most extensive lateral erosion occurred in noncohesive deposits during multiweek hold periods coinciding with flows greater than the mean annual flow, but less than a 2-year flood peak. Channel widening in more cohesive fine sediments of the prodelta and lakebed was less

  11. Assessment of dam removal from geochemical examination of Kuma River sediment, Kyushu, Japan.

    Science.gov (United States)

    Young, Sansfica M; Ishiga, Hiroaki

    2014-12-01

    The aim of this study was to determine if Arase dam gate removal and flushing elevated concentrations of any trace elements in Kuma River and Yatsushiro Bay sediments or caused riverine environmental change. The Arase dam gate on the Kuma River was opened in April 2010. Surface and bottom sediments were compared using 10-cm-long cores (2011) and two grain size fractions. Surface sediment data from 2002, 2012, and 2013 from the Kuma River and Yatsushiro Bay were also compared. The sediments were analyzed using XRF for 23 elements, and the grain size analysis was done. The short core surface and bottom sediments do not show major chemical changes, and therefore, may not represent post-and pre-dam sediments. Results based on 2011 samples show that the removal of the Arase dam gates in 2010 has been geoenvironmentally beneficial due to the decrease of environmentally related trace elements Pb and Zn in 2013. However, a slight increase in the levels of Cr, Cu, Zr, and Nb in 2013 indicates that periodic flushing in winter leads to elevation in these elements due to an increase in the fine fraction. Metal enrichment factors (EF) in 2002 are higher and these have decreased by 2013. Some elements exceed environmental guidelines, but this is due to natural background values, and there is no anthropogenic contamination. Thus, the environment of the river and bay has been significantly improved due to the dam opening. This result suggests that assessment and environmental monitoring studies are very important for dam management and future decision making.

  12. Assessing distribution of migratory fishes and connectivity following complete and partial dam removals in a North Carolina River

    Science.gov (United States)

    Raabe, Joshua K.; Hightower, Joseph E.

    2014-01-01

    Fish, especially migratory species, are assumed to benefit from dam removals that restore connectivity and access to upstream habitat, but few studies have evaluated this assumption. Therefore, we assessed the movement of migratory fishes in the springs of 2008 through 2010 and surveyed available habitat in the Little River, North Carolina, a tributary to the Neuse River, after three complete dam removals and one partial (notched) dam removal. We tagged migratory fishes with PIT tags at a resistance-board weir located at a dam removal site (river kilometer [rkm] 3.7) and followed their movements with an array of PIT antennas. The river-wide distribution of fish following removals varied by species. For example, 24–31% of anadromous American Shad Alosa sapidissima, 45–49% of resident Gizzard Shad Dorosoma cepedianum, and 4–11% of nonnative Flathead CatfishPylodictis olivaris passed the dam removal site at rkm 56 in 2009 and 2010. No preremoval data were available for comparison, but reach connectivity appeared to increase as tagged individuals passed former dam sites and certain individuals moved extensively both upstream and downstream. However, 17–28% did not pass the partially removed dam at rkm 7.9, while 20–39% of those that passed remained downstream for more than a day before migrating upstream. Gizzard Shad required the deepest water to pass this notched structure, followed by American Shad then Flathead Catfish. Fish that passed the notched dam accessed more complex habitat (e.g., available substrate size-classes) in the middle and upper reaches. The results provide strong support for efforts to restore currently inaccessible habitat through complete removal of derelict dams.

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

    Science.gov (United States)

    Pöppl, 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.

  14. First-Year Downstream Sediment Budget Following the Marmot Dam Removal from the Sandy River, Oregon

    Science.gov (United States)

    Podolak, C. J.; Wilcock, P. R.; Pittman, A.

    2008-12-01

    The October 2007 removal of the Marmot Dam, from the Sandy River, OR, provides an opportunity to assess the impact of increased sediment flux on a river channel. The Sandy River drains the west flank of Mt Hood and typically carries a large load of sand and gravel. The 14-meter-tall dam impounded over 750,000 m3 of sediment, only a small amount of which was removed during the decommissioning. Using a one- dimensional modeling approach, it was assessed that the river could transport the accumulated sediment without large adverse impacts downstream of the dam (Cui et al, 2008 - abstract submitted). In order to observe the actual changes to the river due to the dam removal and to test the modeled predictions, a significant monitoring effort has be in place on the Sandy River including bedload and suspended load measurements, discharge measurements, high-fidelity topographic surveys, repeat photography, multiple airborne LIDAR flights, long profile surveys, as well as mapping and characterizing the grain sizes throughout several reaches downstream of the dam. A key step in the quest to describe and predict the spatial distribution of the sediment throughout the downstream reach is to first account for all the sediment (both stored in the reservoir and supplied from upstream). Here, we examine the transport and deposition downstream of the dam through a 2-fraction sediment budget approach using the former dam as the upstream limit of the reach and choosing a the mouth of a bedrock gorge 7 km below the dam site as the downstream limit. Suspended sediment and bedload measurements taken by the USGS just below the dam site (Major et al, 2008 - abstract submitted) are combined with suspended sediment and bedload measurements collected just below the mouth of the gorge and the annual hydrograph to define the sediment fluxes into and out of the reach. Repeat surveys in the reach below the dam (Wallick et al, 2008 - abstract submitted) provide the measure of change in storage

  15. Nearshore biological communities prior to the removal of the Elwha River dams: Chapter 6 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Rubin, Stephen P.; Miller, Ian M.; Elder, Nancy; Reisenbichler, Reginald R.; Duda, Jeffrey J.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    Increases in sediment delivery to coastal waters are expected following removal of dams on the Elwha River, Washington, potentially increasing sediment deposition on the seafloor and suspended sediment in the water column. Biological communities inhabiting shallow, subtidal depths

  16. Particle-bound metal transport after removal of a small dam in the Pawtuxet River, Rhode Island, USA.

    Science.gov (United States)

    Katz, David R; Cantwell, Mark G; Sullivan, Julia C; Perron, Monique M; Burgess, Robert M; Ho, Kay T

    2016-10-06

    The Pawtuxet River in Rhode Island, USA, has a long history of industrial activity and pollutant discharges. Metal contamination of the river sediments is well documented and historically exceeded toxicity thresholds for a variety of organisms. The Pawtuxet River dam, a low-head dam at the mouth of the river, was removed in August 2011. The removal of the dam was part of an effort to restore the riverine ecosystem after centuries of anthropogenic impact. Sediment traps were deployed below the dam to assess changes in metal concentrations and fluxes (Ag, Cd, Cr, Cu, Ni, Pb, and Zn) from the river system into Pawtuxet Cove. Sediment traps were deployed for an average duration of 24 days each, and deployments continued for 15 months after the dam was removed. Metal concentrations in the trapped suspended particulate matter dropped after dam removal (e.g., 460 to 276 mg/kg for Zn) and remained below preremoval levels for most of the study. However, particle-bound metal fluxes increased immediately after dam removal (e.g., 1206 to 4248 g/day for Zn). Changes in flux rates during the study period indicated that river volumetric flow rates acted as the primary mechanism controlling the flux of metals into Pawtuxet Cove and ultimately upper Narragansett Bay. Even though suspended particulate matter metal concentrations initially dropped after removal of the dam, no discernable effect on the concentration or flux of the study metals exiting the river could be associated with removal of the Pawtuxet River dam. Integr Environ Assess Manag 2016;00:000-000. Published 2016. This article is a US Government work and is in the public domain in the USA.

  17. Immediate changes in stream channel geomorphology, aquatic habitat, and fish assemblages following dam removal in a small upland catchment

    Science.gov (United States)

    Magilligan, F. J.; Nislow, K. H.; Kynard, B. E.; Hackman, A. M.

    2016-01-01

    Dam removal is becoming an increasingly important component of river restoration, with > 1100 dams having been removed nationwide over the past three decades. Despite this recent progression of removals, the lack of pre- to post-removal monitoring and assessment limits our understanding of the magnitude, rate, and sequence of geomorphic and/or ecological recovery to dam removal. Taking advantage of the November 2012 removal of an old ( 190 year-old) 6-m high, run-of-river industrial dam on Amethyst Brook (26 km2) in central Massachusetts, we identify the immediate eco-geomorphic responses to removal. To capture the geomorphic responses to dam removal, we collected baseline data at multiple scales, both upstream ( 300 m) and downstream (> 750 m) of the dam, including monumented cross sections, detailed channel-bed longitudinal profiles, embeddedness surveys, and channel-bed grain size measurements, which were repeated during the summer of 2013. These geomorphic assessments were combined with detailed quantitative electrofishing surveys of stream fish richness and abundance above and below the dam site and throughout the watershed and visual surveys of native anadromous sea lamprey (Petromyzon marinus) nest sites. Post-removal assessments were complicated by two events: (1) upstream knickpoint migration exhumed an older (ca. late eighteenth century) intact wooden crib dam 120 m upstream of the former stone dam, and (2) the occurrence of a 10-20 year RI flood 6 months after removal that caused further upstream incision and downstream aggradation. Now that the downstream reach has been reconnected to upstream sediment supply, the predominant geomorphic response was bed aggradation and associated fining (30-60% reduction). At dam proximal locations, aggradation ranged from 0.3 to > 1 m where a large woody debris jam enhanced aggradation. Although less pronounced, distal locations still showed aggradation with a mean depth of deposition of 0.20 m over the 750-m

  18. Long-term Monitoring of Ecological and Geomorphic Adjustments to Dam Removal in an Upland Mesic Catchment

    Science.gov (United States)

    Magilligan, F. J.; Nislow, K. H.; Doyle, H.; Kynard, B.; Dietrich, J. T.

    2015-12-01

    Although more than 1,100 dams have been removed nationally, only 10% have any post-removal assessments with removal of the 6-m high, 200-yr old Pelham Dam in central MA, we sampled geomorphic parameters in Amethyst Brook (23 km2) pre-removal and in each subsequent post-removal year through 2015. We combined these geomorphic assessments with quantitative electrofishing surveys of stream fish richness and abundance above and below the dam and with visual surveys of native anadromous Sea lamprey (Petromyzon marinus) nest sites. Post-removal assessments were complicated by 2 events: upstream knickpoint migration exhumed an older wooden crib dam 120 m upstream of the former dam, and the occurrence of a 20-yr RI flood 6 months after removal. Process-based erosion dominated in the initial post-removal months with significant bed erosion and knickpoint migration occurring through the former reservoir and upstream to the exhumed crib dam that now acts as a grade control. Similar to other removals, the bed aggraded (20 cm) and fined (~50%) downstream in the initial year, with subsequent coarsening (~ 10-20%) in Years 2 and 3, but with D50 still significantly finer than the pre-removal armored bed. The initial fining and subsequent coarsening, unlike previous studies, does not reflect erosion of former reservoir fill but represents the re-connected upstream sediment supply. Ecologically, our monitoring has further underscored the importance of restoring sediment supply and removing barriers to movement to the diversity and abundance of the native fish assemblage. The observed fining has had major implications for Sea lamprey that require fine gravel for spawning, allowing them to spawn in previously unoccupied below-dam sections. Dam removal has also allowed three additional native species to rapidly expand their upstream distribution up to, but not beyond the exhumed dam. Downstream abundances of some species in the first year were markedly reduced in dam-adjacent sections

  19. Contaminated Sediment Management in Dam Removals and River Restoration Efforts: Critical Need for Research and Policy Development

    Science.gov (United States)

    Evans, J. E.

    2015-12-01

    Over 1,000 U.S. dams have been removed (1975-2015) for reasons including obsolescence, liability concerns, water quality upgrades, fisheries, or ecosystem enhancements. Contaminated sediment can significantly complicate the approval process, cost, and timeline of a dam removal, or stop it entirely. In a dam removal, reservoir sediment changes from a sink to a source of contaminants. Recently, the Sierra Club sued to stop the removal of a large dam in Ohio because of the potential impact of phosphate releases on toxic algal blooms in Lake Erie. Heavy metals, PCBs, PAHs, pesticides, and petroleum hydrocarbons can be present in reservoir sediments. In a non-dam removal scenario, reservoir management tools range from "no action" to dredging, dewatering and removal, or sediment capping. But it is not clear how these reservoir management techniques apply to dam removals. Case studies show typically >80% of the reservoir sediment is eventually eroded, precluding sediment capping as a containment option. However, the released contaminants are diluted by mixing with "clean" sediment and are transported to different physio-chemical environments which may immobilize or biodegrade the contaminants. Poorly understood options include phased drawdown/reseeding the former reservoir to contain sediments, diking contaminant "hot spots," and addressing contaminant stratigraphy (where historical use created "hot layers" in the reservoir sediment). Research and policy development needs include: (1) assessment methods based on synergistic effects of multiple contaminants being present; (2) ways to translate the pre-removal contaminant concentrations to post-removal health risks downstream; (3) evaluation of management practices for contaminant "hot spots" and "hot layers;" (4) tools to forecast the presence of contaminated sediment using easily accessible information; and (5) ways to limit liability risk for organizations participating in dam removals involving contaminated sediment.

  20. Effects of Large Dam Removal and Groundwater Pumping on Stream Temperature under Humid, Semiarid, and Arid Conditions

    Science.gov (United States)

    Risley, J. C.; Constantz, J. E.; Essaid, H.; Rounds, S. A.

    2010-12-01

    The effects of large upstream dam removal and in-reach groundwater pumping on streamflows and stream temperature was analyzed for humid, semiarid, and arid conditions with long dry seasons representing typical climate conditions where large dams are present, such as the western US or eastern Australia. A MODFLOW-2000 model, with options for stream-aquifer interaction and grid-block rewetting, was constructed to simulate monthly streamflows for 12 watershed scenarios described below. For each scenario, streamflow output became input into a stream temperature simulation model. Stream temperatures were simulated using the CE-QUAL-W2 water quality model over a 110 km model grid, with the presence and removal of a dam at the top of the reach and pumping in the lower 60 km of the reach. Measured meteorological data from three locations in Oregon and California representing the three meterologic conditions were used as model input to simulate the impact of varying climate conditions on streamflows and stream temperature. For each climate condition, four hypothetical watershed scenarios were modeled: (1) natural (no dam or pumping), (2) large upstream dam present, (3) dam with in-reach pumping, and (4) no dam with pumping continued, resulting in 12 cases. Dam removal, in the presence or absence of pumping, created significant changes in streamflow characteristics, resulting in significant changes in stream temperature throughout the year for all three climate conditions. From March to August, the presence of a dam caused monthly mean stream temperatures to decrease on average by approximately 3.0°C, 2.5°C, and 2.0°C for the humid, semiarid, and arid conditions, respectively; however, stream temperatures generally increased from September to February. Pumping caused stream temperatures to warm in summer and cool in winter by generally less than 0.5°C. Though dam removal led to greater changes in stream temperature than pumping, ephemeral conditions were increased both

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

    Energy Technology Data Exchange (ETDEWEB)

    Cope, Michael G. [Montana State Univ., Bozeman, MT (United States)]|[Montana Dept. of Fish, Wildlife and Parks, Kalispell, MT (United States)

    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. Anticipated sediment delivery to the lower Elwha River during and following dam removal: Chapter 2 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Czuba, Christiana R.; Randle, Timothy J.; Bountry, Jennifer A.; Magirl, Christopher S.; Czuba, Jonathan A.; Curran, Christopher A.; Konrad, Christopher P.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    During and after the planned incremental removal of two large, century-old concrete dams between 2011 and 2014, the sediment-transport regime in the lower Elwha River of western Washington will initially spike above background levels and then return to pre-dam conditions some years after complete dam removal. Measurements indicate the upper reaches of the steep-gradient Elwha River, draining the northeast section of the Olympic Mountains, carries between an estimated 120,000 and 290,000 cubic meters of sediment annually. This large load has deposited an estimated 19 million cubic meters of sediment within the two reservoirs formed by the Elwha and Glines Canyon Dams. It is anticipated that from 7 to 8 million cubic meters of this trapped sediment will mobilize and transport downstream during and after dam decommissioning, restoring the downstream sections of the sediment-starved river and nearshore marine environments. Downstream transport of sediment from the dam sites will have significant effects on channel morphology, water quality, and aquatic habitat during and after dam removal. Sediment concentrations are expected to be between 200 and 1,000 milligrams per liter during and just after dam removal and could rise to as much as 50,000 milligrams per liter during high flows. Downstream sedimentation in the river channel and flood plain will be potentially large, particularly in the lower Elwha River, an alluvial reach with a wide flood plain. Overall aggradation could be as much as one to several meters. Not all reservoir sediment, however, will be released to the river. Some material will remain on hill slopes and flood plains within the drained reservoirs in quantities that will depend on the hydrology, precipitation, and mechanics of the incising channel. Eventually, vegetation will stabilize this remaining reservoir sediment, and the overall sediment load in the restored river will return to pre-dam levels.

  3. Using a sediment budget to understand geomorphic response following dam removal

    Science.gov (United States)

    Major, J. J.; O'Connor, J. E.; Podolak, C.; Keith, M.; Spicer, K.; Pittman, S.; Bragg, H.; Wallick, J.; Grant, G.

    2013-12-01

    Dam removal provides an exceptional setting for developing tightly constrained sediment budgets linking reservoir erosion with downstream deposition. Measurements of erosion of impounded sediment can provide precise values on sediment input, and measurements of downstream flux and deposition provide potentially well-constrained estimates of output and storage. Measurements of sediment erosion, flux, deposition, and composition following the 2007 breaching of Marmot Dam, Oregon, allowed construction of size-fraction sediment budgets for the first year following dam removal, which documented the spatial distributions and fluxes of nearly 400,000 m3 of sand and gravel released from the former reservoir. The budget encompassed a ~25-km-long control-volume-reach of the Sandy River extending from about 10 km upstream of the dam site to about 15 km downstream. Budget components consisted of measurements of sediment flux into the reservoir reach, erosion from the reservoir reach, sediment flux and deposition along a 2-km-long reach immediately downstream of the dam site before the river entered a 7-km-long bedrock gorge, and sediment flux out of the gorge. Our results show that channel morphology strongly filtered the flux and distribution of released sediment. About 70-90 percent of the gravel released by reservoir erosion deposited within 2 km of the dam site, whereas sand largely passed into and through the bedrock gorge. Flux measurements ~8 km beyond the gorge exit indicate that about half the sand load that emerged from the gorge deposited in the intervening 8-km channel reach. Combining flux measurements with volumetric measurements of erosion and deposition greatly aided construction and interpretation of the sediment budget. Despite the immense effort exerted to measure sediment erosion (relatively easy; cost effective), flux (very challenging; expensive), and deposition (relatively easy above gorge; cost effective), and the tight spatial distributions of the

  4. Assessing potential removal of low-head dams in urban settings: an example from the Ottawa River, NW Ohio.

    Science.gov (United States)

    Roberts, Sheila J; Gottgens, Johan F; Spongberg, Alison L; Evans, James E; Levine, Norman S

    2007-01-01

    This is a study of the scientific component of an effort to restore an urban river by removing a low-head dam. The Secor Dam is owned by a local government entity near Toledo, Ohio. The proposed removal of the last structure impeding flow on the Ottawa River has broad appeal, but the owner is concerned about liability issues, particularly potential changes to the flood regime, the presence of contaminated sediments behind the dam, and possible downstream transport of reservoir sediments. Assessing sediment contamination involved sediment sampling and analysis of trace metals and organic contaminants. Forecasting sediment transport involved field methods to determine the volume and textural properties of reservoir and upstream sediment and calculations to determine the fate of reservoir sediments. Forecasting changes in the flood regime involved HEC-RAS hydrological models to determine before and after dam removal flood scenarios using LiDAR data imported into an ArcGIS database. The resulting assessment found potential sediment contamination to be minor, and modeling showed that the removal of the dam would have minimal impacts on sediment transport and flood hazards. Based on the assessment, the removal of the dam has been approved by its owners.

  5. Effects of Dam Removal on Fish Community Interactions and Stability in the Eightmile River System, Connecticut, USA

    Science.gov (United States)

    Poulos, Helen M.; Chernoff, Barry

    2017-02-01

    New multivariate time-series methods have the potential to provide important insights into the effects of ecosystem restoration activities. To this end, we examined the temporal effects of dam removal on fish community interactions using multivariate autoregressive models to understand changes in fish community structure in the Eightmile River System, Connecticut, USA. We sampled fish for 6 years during the growing season; 1 year prior to, 2 years during, and for 3 years after a small dam removal event. The multivariate autoregressive analysis revealed that the site above the dam was the most reactive and least resilient sample site, followed in order by the below-dam and nearby reference site. Even 3 years after the dam removal event, the stream was still in a recovery stage that had failed to approximate the community structure of the reference site. This suggests that the reorganization of fish communities following dam removals, with the goal of ecological restoration, may take decades to centuries for the restored sites to approximate the community structure of nearby undisturbed sites. Results from this study also highlight the utility of multivariate autoregressive modeling for examining temporal interactions among species in response to adaptive management activities both in aquatic systems and elsewhere.

  6. China’s Policy on Dams at the Crossroads: Removal or Further Construction?

    Directory of Open Access Journals (Sweden)

    Chiyuan Miao

    2015-05-01

    Full Text Available During the past century, the number and scale of reservoirs worldwide has grown substantially to meet the demand for water and hydropower arising from increased population, industrialization, and urbanization. This is particularly the case in China, where reservoir construction increased rapidly after the Chinese economic reform and the introduction of open-door policies. On average, 4.4 large reservoirs with a capacity greater than 0.1 km3 were constructed per annum during the 1970s–1990s. This average reached 11.8 such reservoirs per annum in the 2000s. Considering the adverse impact of dams on rivers and riparian communities, various environmentalists and non-governmental organizations in China have begun to protest against the construction of dams. Now China’s policy on dams is at a crossroads: Removal or further construction? In this paper, we systematically assess the construction of reservoirs in China and discuss the benefits and drawbacks of large-scale reservoir projects on several major rivers in China: The Yangtze River, the Yellow River and the Mekong River. Lastly, we provide a perspective on the future of reservoir development in China, taking into account natural conditions, renewable hydropower resources, and greenhouse gas emissions.

  7. Upstream movements of Atlantic Salmon in the Lower Penobscot River, Maine following two dam removals and fish passage modifications

    Science.gov (United States)

    Izzo, Lisa K.; Maynard, George A.; Zydlewski, Joseph

    2016-01-01

    The Penobscot River Restoration Project (PRRP), to be completed in 2016, involved an extensive plan of dam removal, increases in hydroelectric capacity, and fish passage modifications to increase habitat access for diadromous species. As part of the PRRP, Great Works and Veazie dams were removed, making Milford Dam the first impediment to federally endangered Atlantic Salmon Salmo salar. Upstream habitat access for Atlantic Salmon is dependent upon successful and timely passage at Milford Dam because nearly all suitable spawning habitat is located upstream. In 2014 and 2015, a total of 73 adult salmon were radio-tagged to track their upstream movements through the Penobscot River to assess potential delays at (1) the dam remnants, (2) the confluence of the Stillwater Branch and the main stem of the Penobscot River below the impassable Orono Dam, and (3) the Milford Dam fish lift (installed in 2014). Movement rates through the dam remnants and the Stillwater confluence were comparable to open river reaches. Passage efficiency of the fish lift was high in both years (95% and 100%). However, fish experienced long delays at Milford Dam, with approximately one-third of fish taking more than a week to pass in each year, well below the Federal Energy Regulatory Commission passage standard of 95% within 48 h. Telemetry indicates most fish locate the fishway entrance within 5 h of arrival and were observed at the entrance at all hours of the day. These data indicate that overall transit times through the lower river were comparable to reported movement rates prior to changes to the Penobscot River due to the substantial delays seen at Milford Dam. The results of this study show that while adult Atlantic Salmon locate the new fish lift entrance quickly, passage of these fish was significantly delayed under 2014–2015 operations.

  8. Juvenile salmonid monitoring in the White Salmon River, Washington, post-Condit Dam removal, 2016

    Science.gov (United States)

    Jezorek, Ian G.; Hardiman, Jill M.

    2017-06-23

    Condit Dam, at river kilometer 5.3 on the White Salmon River, Washington, was breached in 2011 and removed completely in 2012, allowing anadromous salmonids access to habitat that had been blocked for nearly 100 years. A multi-agency workgroup concluded that the preferred salmonid restoration alternative was natural recolonization with monitoring to assess efficacy, followed by a management evaluation 5 years after dam removal. Limited monitoring of salmon and steelhead spawning has occurred since 2011, but no monitoring of juveniles occurred until 2016. During 2016, we operated a rotary screw trap at river kilometer 2.3 (3 kilometers downstream of the former dam site) from late March through May and used backpack electrofishing during summer to assess juvenile salmonid distribution and abundance. The screw trap captured primarily steelhead (Oncorhynchus mykiss; smolts, parr, and fry) and coho salmon (O. kisutch; smolts and fry). We estimated the number of steelhead smolts at 3,851 (standard error = 1,454) and coho smolts at 1,093 (standard error = 412). In this document, we refer to O. mykiss caught at the screw trap as steelhead because they were actively migrating, but because we did not know migratory status of O. mykiss caught in electrofishing surveys, we simply refer to them as O. mykiss or steelhead/rainbow trout. Steelhead and coho smolts tagged with passive integrated transponder tags were subsequently detected downstream at Bonneville Dam on the Columbia River. Few Chinook salmon (O. tshawytscha) fry were captured, possibly as a result of trap location or effects of a December 2015 flood. Sampling in Mill, Buck, and Rattlesnake Creeks (all upstream of the former dam site) showed that juvenile coho were present in Mill and Buck Creeks, suggesting spawning had occurred there. We compared O. mykiss abundance data in sites on Buck and Rattlesnake Creeks to pre-dam removal data. During 2016, age-0 O. mykiss were more abundant in Buck Creek than in 2009 or

  9. Large-scale dam removal on the Elwha River, Washington, USA: Fluvial sediment load

    Science.gov (United States)

    Magirl, Christopher S.; Hilldale, Robert C.; Curran, Christopher A.; Duda, Jeffrey J.; Straub, Timothy D.; Domanski, Marian; Foreman, James R.

    2015-10-01

    The Elwha River restoration project, in Washington State, includes the largest dam-removal project in United States history to date. Starting September 2011, two nearly century-old dams that collectively contained 21 ± 3 million m3 of sediment were removed over the course of three years with a top-down deconstruction strategy designed to meter the release of a portion of the dam-trapped sediment. Gauging with sediment-surrogate technologies during the first two years downstream from the project measured 8,200,000 ± 3,400,000 tonnes of transported sediment, with 1,100,000 and 7,100,000 t moving in years 1 and 2, respectively, representing 3 and 20 times the Elwha River annual sediment load of 340,000 ± 80,000 t/y. During the study period, the discharge in the Elwha River was greater than normal (107% in year 1 and 108% in year 2); however, the magnitudes of the peak-flow events during the study period were relatively benign with the largest discharge of 292 m3/s (73% of the 2-year annual peak-flow event) early in the project when both extant reservoirs still retained sediment. Despite the muted peak flows, sediment transport was large, with measured suspended-sediment concentrations during the study period ranging from 44 to 16,300 mg/L and gauged bedload transport as large as 24,700 t/d. Five distinct sediment-release periods were identified when sediment loads were notably increased (when lateral erosion in the former reservoirs was active) or reduced (when reservoir retention or seasonal low flows and cessation of lateral erosion reduced sediment transport). Total suspended-sediment load was 930,000 t in year 1 and 5,400,000 t in year 2. Of the total 6,300,000 ± 3,200,000 t of suspended-sediment load, 3,400,000 t consisted of silt and clay and 2,900,000 t was sand. Gauged bedload on the lower Elwha River in year 2 of the project was 450,000 ± 360,000 t. Bedload was not quantified in year 1, but qualitative observations using bedload-surrogate instruments

  10. Baseline hydrologic studies in the lower Elwha River prior to dam removal

    Science.gov (United States)

    Magirl, Christopher S.; Curran, Christopher A.; Sheibley, Rich W.; Warrick, Jonathan A.; Czuba, Jonathan A.; Czuba, Christiana R.; Gendaszek, Andrew S.; Shafroth, Patrick B.; Duda, Jeffrey J.; Foreman, James R.

    2011-01-01

    After the removal of two large, long‑standing dams on the Elwha River, Washington, the additional load of sediment and wood is expected to affect the hydrology of the lower river, its estuary, and the alluvial aquifer underlying the surrounding flood plain. To better understand the surface-water and groundwater characteristics of the river and estuary before dam removal, several hydrologic data sets were collected and analyzed. An experiment using a dye tracer characterized transient storage, and it was determined that the low‑flow channel of the lower Elwha River was relatively simple; 1–6 percent of the median travel time of dye was attributed to transient‑storage processes. Water data from monitoring wells adjacent to the main‑stem river indicated a strong hydraulic connectivity between stage in the river and groundwater levels in the flood plain. Analysis of temperature data from the monitoring wells showed that changes in the groundwater temperature responded weeks or months after water temperature changed in the river. A seepage investigation indicated that water from the river was moving into the aquifer (losing

  11. Delta Morphodynamics from River Sediment Input: Dam Removal, Elwha River, Washington, USA.

    Science.gov (United States)

    Warrick, J. A.; Gelfenbaum, G. R.; Stevens, A. W.; Miller, I. M.; Kaminsky, G. M.; Ritchie, A.

    2015-12-01

    Sediment supply plays an important role in river delta morphodynamics and sustainability, and it is important to evaluate how deltas respond to the restoration or enhancement of sediment supplies. Here we report on the morphodynamic responses of the Elwha River delta to large increases in river sediment loads from the removal of two large dams beginning in 2011. The dam removal project exposed ~30 million tonnes of sediment stored within the former reservoirs to natural erosion by the river, and roughly half of this reservoir sediment was eroded during the first four years of the project. Coastal surveys with GPS-based mapping systems, sonar, and aerial photography have revealed that the Elwha River mouth has expanded seaward by ~500 m with the introduction of new supplies of sediment. Approximately 3.5 million cubic meters (or ~5 million tonnes) of sediment were deposited at the river mouth delta between 2011 and 2015. This newly deposited sediment has been shaped by waves and currents into a series of dynamic bars that have greatly expanded the estuarine habitats of the delta.

  12. Stream Temperature Spatial and Temporal Response to Large Dam Removal and Groundwater Pumping under Varying Climate Conditions

    Science.gov (United States)

    Risley, J. C.; Constantz, J. E.; Essaid, H.; Rounds, S. A.

    2016-12-01

    We simulated the effects of large upstream dam removal and in-reach groundwater pumping on stream temperature spatial and temporal patterns in a hypothetical river basin under varying climate conditions. A MODFLOW-2000 model, with options for stream-aquifer interaction and grid-block rewetting, was constructed to simulate monthly streamflows for 12 watershed scenarios described below. For each scenario, streamflow output became input into a stream temperature simulation model. Stream temperatures were simulated using the CE-QUAL-W2 water quality model over a 110 km model grid, with the presence and removal of a dam at the top of the reach and pumping in the lower 60 km of the reach. Measured meteorological data from three locations in Oregon and California representing the three meteorological conditions were used as model input to simulate the impact of varying climate conditions on streamflows and stream temperature. For each climate condition, four hypothetical watershed scenarios were modeled: (1) natural (no dam or pumping), (2) large upstream dam present, (3) dam with in-reach pumping, and (4) no dam with pumping continued, resulting in 12 cases. If a transition from a humid to more arid environment occurs under future climate change, the simulations showed that decreased streamflow, increased solar radiation, and increased air temperatures would result in overall increased stream temperatures as expected. From March to August, the presence of a dam caused monthly mean stream temperatures to decrease on average by approximately 3.0°C, 2.5°C, and 2.0°C for the humid, semiarid, and arid conditions, respectively; however, stream temperatures generally increased from September to February. Pumping caused stream temperatures to warm in summer and cool in winter by generally less than 0.5°C. Though dam removal led to greater changes in stream temperature than pumping, ephemeral conditions were increased both temporally and spatially by pumping.

  13. Predicting the type, location and magnitude of geomorphic responses to dam removal: Role of hydrologic and geomorphic constraints

    Science.gov (United States)

    Gartner, John D.; Magilligan, Francis J.; Renshaw, Carl E.

    2015-12-01

    Using a dam removal on the Ashuelot River in southern New Hampshire, we test how a sudden, spatially non-uniform increase in river slope alters sediment transport dynamics and riparian sediment connectivity. Site conditions were characterized by detailed pre- and post-removal field surveys and high-resolution aerial lidar data, and locations of erosion and deposition were predicted through one-dimensional hydrodynamic modeling. The Homestead Dam was a ~ 200 year old, 4 m high, 50 m wide crib dam that created a 9.5 km long, relatively narrow reservoir. Following removal, an exhumed resistant bed feature of glaciofluvial boulders located 400 m upstream and ~ 2.5 m lower than the crest of the dam imposed a new boundary condition in the drained reservoir, acting as a grade control that maintained a backwater effect upstream. During the 15 months following removal, non-uniform erosion in the former reservoir totaled ~ 60,000 m3 (equivalent to ~ 9.3 cm when averaged across the reservoir). Net deposition of ~ 10,700 m3 was measured downstream of the dam, indicating most sediment from the reservoir was carried more than 8 km downstream beyond the study area. The most pronounced bed erosion occurred where modeled sediment transport increased in the downstream direction, and deposition occurred both within and downstream of the former reservoir where modeled sediment transport decreased in the downstream direction. We thus demonstrate that spatial gradients in sediment transport can be used to predict locations of erosion and deposition on the stream bed. We further observed that bed incision was not a necessary condition for bank erosion in the former reservoir. In this characteristically narrow and shallow reservoir lacking abundant dam-induced sedimentation, the variable resistance of the bed and banks acted as geomorphic constraints. Overall, the response deviated from the common conceptual model of knickpoint erosion and channel widening due to dam removal. With

  14. Effects of removing Good Hope Mill Dam on selected physical, chemical, and biological characteristics of Conodoguinet Creek, Cumberland County, Pennsylvania

    Science.gov (United States)

    Chaplin, Jeffrey J.; Brightbill, Robin A.; Bilger, Michael D.

    2005-01-01

    The implications of dam removal on channel characteris-tics, water quality, benthic invertebrates, and fish are not well understood because of the small number of removals that have been studied. Comprehensive studies that document the effects of dam removal are just beginning to be published, but most research has focused on larger dams or on the response of a sin-gle variable (such as benthic invertebrates). This report, pre-pared in cooperation with the Conodoguinet Creek Watershed Association, provides an evaluation of how channel morphol-ogy, bed-particle-size distribution, water quality, benthic inver-tebrates, fish, and aquatic habitat responded after removal of Good Hope Mill Dam (a small 'run of the river' dam) from Conodoguinet Creek in Cumberland County, Pa. Good Hope Mill Dam was a 6-foot high, 220-foot wide concrete structure demolished and removed over a 3-day period beginning with the initial breach on November 2, 2001, at 10:00 a.m. eastern standard time. To isolate the effects of dam removal, data were collected before and after dam removal at five monitoring stations and over selected reaches upstream, within, and downstream of the impoundment. Stations 1, 2, and 5 were at free-flowing control locations 4.9 miles upstream, 2.5 miles upstream, and 5 miles downstream of the dam, respec-tively. Stations 3 and 4 were located where the largest responses were anticipated, 115 feet upstream and 126 feet downstream of the dam, respectively Good Hope Mill Dam was not an effective barrier to sedi-ment transport. Less than 3 inches of sediment in the silt/clay-size range (less than 0.062 millimeters) coated bedrock within the 7,160-foot (1.4-mile) impoundment. The bedrock within the impoundment was not incised during or after dam removal, and the limited sediment supply resulted in no measurable change in the thalweg elevation downstream of the dam. The cross-sec-tional areas at stations 3 and 4, measured 17 days and 23 months after dam removal, were within

  15. Geomorphic response of the Sandy River, Oregon, to removal of Marmot Dam

    Science.gov (United States)

    Major, Jon J.; O'Connor, Jim E.; Podolak, Charles J.; Keith, Mackenzie K.; Grant, Gordon E.; Spicer, Kurt R.; Pittman, Smokey; Bragg, Heather M.; Wallick, J. Rose; Tanner, Dwight Q.; Rhode, Abagail; Wilcock, Peter R.

    2012-01-01

    The October 2007 breaching of a temporary cofferdam constructed during removal of the 15-meter (m)-tall Marmot Dam on the Sandy River, Oregon, triggered a rapid sequence of fluvial responses as ~730,000 cubic meters (m3) of sand and gravel filling the former reservoir became available to a high-gradient river. Using direct measurements of sediment transport, photogrammetry, airborne light detection and ranging (lidar) surveys, and, between transport events, repeat ground surveys of the reservoir reach and channel downstream, we monitored the erosion, transport, and deposition of this sediment in the hours, days, and months following breaching of the cofferdam. Rapid erosion of reservoir sediment led to exceptional suspended-sediment and bedload-sediment transport rates near the dam site, as well as to elevated transport rates at downstream measurement sites in the weeks and months after breaching. Measurements of sediment transport 0.4 kilometers (km) downstream of the dam site during and following breaching show a spike in the transport of fine suspended sediment within minutes after breaching, followed by high rates of suspended-load and bedload transport of sand. Significant transport of gravel bedload past the measurement site did not begin until 18 to 20 hours after breaching. For at least 7 months after breaching, bedload transport rates just below the dam site during high flows remained as much as 10 times above rates measured upstream of the dam site and farther downstream. The elevated sediment load was derived from eroded reservoir sediment, which began eroding when a meters-tall knickpoint migrated about 200 m upstream in the first hour after breaching. Rapid knickpoint migration triggered vertical incision and bank collapse in unconsolidated sand and gravel, leading to rapid channel widening. Over the following days and months, the knickpoint migrated upstream more slowly, simultaneously decreasing in height and becoming less distinct. Within 7 months

  16. Large-scale dam removal on the Elwha River, Washington, USA: source-to-sink sediment budget and synthesis

    Science.gov (United States)

    Warrick, Jonathan A.; Bountry, Jennifer A.; East, Amy E.; Magirl, Christopher S.; Randle, Timothy J.; Gelfenbaum, Guy R.; Ritchie, Andrew C.; Pess, George R.; Leung, Vivian; Duda, Jeff J.

    2015-01-01

    Understanding landscape responses to sediment supply changes constitutes a fundamental part of many problems in geomorphology, but opportunities to study such processes at field scales are rare. The phased removal of two large dams on the Elwha River, Washington, exposed 21 ± 3 million m3, or ~ 30 million tonnes (t), of sediment that had been deposited in the two former reservoirs, allowing a comprehensive investigation of watershed and coastal responses to a substantial increase in sediment supply. Here we provide a source-to-sink sediment budget of this sediment release during the first two years of the project (September 2011–September 2013) and synthesize the geomorphic changes that occurred to downstream fluvial and coastal landforms. Owing to the phased removal of each dam, the release of sediment to the river was a function of the amount of dam structure removed, the progradation of reservoir delta sediments, exposure of more cohesive lakebed sediment, and the hydrologic conditions of the river. The greatest downstream geomorphic effects were observed after water bodies of both reservoirs were fully drained and fine (silt and clay) and coarse (sand and gravel) sediments were spilling past the former dam sites. After both dams were spilling fine and coarse sediments, river suspended-sediment concentrations were commonly several thousand mg/L with ~ 50% sand during moderate and high river flow. At the same time, a sand and gravel sediment wave dispersed down the river channel, filling channel pools and floodplain channels, aggrading much of the river channel by ~ 1 m, reducing river channel sediment grain sizes by ~ 16-fold, and depositing ~ 2.2 million m3 of sand and gravel on the seafloor offshore of the river mouth. The total sediment budget during the first two years revealed that the vast majority (~ 90%) of the sediment released from the former reservoirs to the river passed through the fluvial system and was discharged to the coastal

  17. Large-scale dam removal on the Elwha River, Washington, USA: Source-to-sink sediment budget and synthesis

    Science.gov (United States)

    Warrick, Jonathan A.; Bountry, Jennifer A.; East, Amy E.; Magirl, Christopher S.; Randle, Timothy J.; Gelfenbaum, Guy; Ritchie, Andrew C.; Pess, George R.; Leung, Vivian; Duda, Jeffrey J.

    2015-10-01

    Understanding landscape responses to sediment supply changes constitutes a fundamental part of many problems in geomorphology, but opportunities to study such processes at field scales are rare. The phased removal of two large dams on the Elwha River, Washington, exposed 21 ± 3 million m3, or 30 million tonnes (t), of sediment that had been deposited in the two former reservoirs, allowing a comprehensive investigation of watershed and coastal responses to a substantial increase in sediment supply. Here we provide a source-to-sink sediment budget of this sediment release during the first two years of the project (September 2011-September 2013) and synthesize the geomorphic changes that occurred to downstream fluvial and coastal landforms. Owing to the phased removal of each dam, the release of sediment to the river was a function of the amount of dam structure removed, the progradation of reservoir delta sediments, exposure of more cohesive lakebed sediment, and the hydrologic conditions of the river. The greatest downstream geomorphic effects were observed after water bodies of both reservoirs were fully drained and fine (silt and clay) and coarse (sand and gravel) sediments were spilling past the former dam sites. After both dams were spilling fine and coarse sediments, river suspended-sediment concentrations were commonly several thousand mg/L with 50% sand during moderate and high river flow. At the same time, a sand and gravel sediment wave dispersed down the river channel, filling channel pools and floodplain channels, aggrading much of the river channel by 1 m, reducing river channel sediment grain sizes by 16-fold, and depositing 2.2 million m3 of sand and gravel on the seafloor offshore of the river mouth. The total sediment budget during the first two years revealed that the vast majority ( 90%) of the sediment released from the former reservoirs to the river passed through the fluvial system and was discharged to the coastal waters, where slightly less

  18. Large-scale dam removal on the Elwha River, Washington, USA: river channel and floodplain geomorphic change

    Science.gov (United States)

    East, Amy E.; Pess, George R.; Bountry, Jennifer A.; Magirl, Christopher S.; Ritchie, Andrew C.; Logan, Joshua; Randle, Timothy J.; Mastin, Mark C.; Minear, Justin T.; Duda, Jeffrey J.; Liermann, Martin C.; McHenry, Michael L.; Beechie, Timothy J.; Shafroth, Patrick B.

    2015-01-01

    A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sediment released during the largest dam removal in history, on the Elwha River, Washington, USA, by measuring changes in riverbed elevation and topography, bed sediment grain size, and channel planform as two dams were removed in stages over two years.

  19. Large-scale dam removal on the Elwha River, Washington, USA: fluvial sediment load

    Science.gov (United States)

    Magirl, Christopher S.; Hilldale, Robert C.; Curran, Christopher A.; Duda, Jeffrey J.; Straub, Timothy D.; Domanski, Marian M.; Foreman, James R.

    2015-01-01

    The Elwha River restoration project, in Washington State, includes the largest dam-removal project in United States history to date. Starting September 2011, two nearly century-old dams that collectively contained 21 ± 3 million m3 of sediment were removed over the course of three years with a top-down deconstruction strategy designed to meter the release of a portion of the dam-trapped sediment. Gauging with sediment-surrogate technologies during the first two years downstream from the project measured 8,200,000 ± 3,400,000 tonnes of transported sediment, with 1,100,000 and 7,100,000 t moving in years 1 and 2, respectively, representing 3 and 20 times the Elwha River annual sediment load of 340,000 ± 80,000 t/y. During the study period, the discharge in the Elwha River was greater than normal (107% in year 1 and 108% in year 2); however, the magnitudes of the peak-flow events during the study period were relatively benign with the largest discharge of 292 m3/s (73% of the 2-year annual peak-flow event) early in the project when both extant reservoirs still retained sediment. Despite the muted peak flows, sediment transport was large, with measured suspended-sediment concentrations during the study period ranging from 44 to 16,300 mg/L and gauged bedload transport as large as 24,700 t/d. Five distinct sediment-release periods were identified when sediment loads were notably increased (when lateral erosion in the former reservoirs was active) or reduced (when reservoir retention or seasonal low flows and cessation of lateral erosion reduced sediment transport). Total suspended-sediment load was 930,000 t in year 1 and 5,400,000 t in year 2. Of the total 6,300,000 ± 3,200,000 t of suspended-sediment load, 3,400,000 t consisted of silt and clay and 2,900,000 t was sand. Gauged bedload on the lower Elwha River in year 2 of the project was 450,000 ± 360,000 t. Bedload was not quantified in year 1, but qualitative observations using bedload

  20. Large-scale dam removal on the Elwha River, Washington, USA: River channel and floodplain geomorphic change

    Science.gov (United States)

    East, Amy E.; Pess, George R.; Bountry, Jennifer A.; Magirl, Christopher S.; Ritchie, Andrew C.; Logan, Joshua B.; Randle, Timothy J.; Mastin, Mark C.; Minear, Justin T.; Duda, Jeffrey J.; Liermann, Martin C.; McHenry, Michael L.; Beechie, Timothy J.; Shafroth, Patrick B.

    2015-01-01

    A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sediment released during the largest dam removal in history, on the Elwha River, Washington, USA, by measuring changes in riverbed elevation and topography, bed sediment grain size, and channel planform as two dams were removed in stages over two years. As 10.5 million t (7.1 million m3) of sediment was released from two former reservoirs, downstream dispersion of a sediment wave caused widespread bed aggradation of ~ 1 m (greater where pools filled), changed the river from pool-riffle to braided morphology, and decreased the slope of the lowermost river. The newly deposited sediment, which was finer than most of the pre-dam-removal bed, formed new bars (largely pebble, granule, and sand material), prompting aggradational channel avulsion that increased the channel braiding index by almost 50%. As a result of mainstem bed aggradation, floodplain channels received flow and accumulated new sediment even during low to moderate flow conditions. The river system showed a two- to tenfold greater geomorphic response to dam removal (in terms of bed elevation change magnitude) than it had to a 40-year flood event four years before dam removal. Two years after dam removal began, as the river had started to incise through deposits of the initial sediment wave, ~ 1.2 million t of new sediment (~ 10% of the amount released from the two reservoirs) was stored along 18 river km of the mainstem channel and 25 km of floodplain channels. The Elwha River thus was able to transport most of the released sediment to the river mouth. The geomorphic alterations and changing bed sediment grain size along

  1. Reprint of: Large-scale dam removal on the Elwha River, Washington, USA: River channel and floodplain geomorphic change

    Science.gov (United States)

    East, Amy E.; Pess, George R.; Bountry, Jennifer A.; Magirl, Christopher S.; Ritchie, Andrew C.; Logan, Joshua B.; Randle, Timothy J.; Mastin, Mark C.; Minear, Justin T.; Duda, Jeffrey J.; Liermann, Martin C.; McHenry, Michael L.; Beechie, Timothy J.; Shafroth, Patrick B.

    2015-10-01

    A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sediment released during the largest dam removal in history, on the Elwha River, Washington, USA, by measuring changes in riverbed elevation and topography, bed sediment grain size, and channel planform as two dams were removed in stages over two years. As 10.5 million t (7.1 million m3) of sediment was released from two former reservoirs, downstream dispersion of a sediment wave caused widespread bed aggradation of 1 m (greater where pools filled), changed the river from pool-riffle to braided morphology, and decreased the slope of the lowermost river. The newly deposited sediment, which was finer than most of the pre-dam-removal bed, formed new bars (largely pebble, granule, and sand material), prompting aggradational channel avulsion that increased the channel braiding index by almost 50%. As a result of mainstem bed aggradation, floodplain channels received flow and accumulated new sediment even during low to moderate flow conditions. The river system showed a two- to tenfold greater geomorphic response to dam removal (in terms of bed elevation change magnitude) than it had to a 40-year flood event four years before dam removal. Two years after dam removal began, as the river had started to incise through deposits of the initial sediment wave, 1.2 million t of new sediment ( 10% of the amount released from the two reservoirs) was stored along 18 river km of the mainstem channel and 25 km of floodplain channels. The Elwha River thus was able to transport most of the released sediment to the river mouth. The geomorphic alterations and changing bed sediment grain size along the

  2. Aquatic ecology of the Elwha River estuary prior to dam removal: Chapter 7 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Duda, Jeffrey J.; Beirne, Matthew M.; Larsen, Kimberly; Barry, Dwight; Stenberg, Karl; McHenry, Michael L.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    The removal of two long-standing dams on the Elwha River in Washington State will initiate a suite of biological and physical changes to the estuary at the river mouth. Estuaries represent a transition between freshwater and saltwater, have unique assemblages of plants and animals, and are a critical habitat for some salmon species as they migrate to the ocean. This chapter summarizes a number of studies in the Elwha River estuary, and focuses on physical and biological aspects of the ecosystem that are expected to change following dam removal. Included are data sets that summarize (1) water chemistry samples collected over a 16 month period; (2) beach seining activities targeted toward describing the fish assemblage of the estuary and migratory patterns of juvenile salmon; (3) descriptions of the aquatic and terrestrial invertebrate communities in the estuary, which represent an important food source for juvenile fish and are important water quality indicators; and (4) the diet and growth patterns of juvenile Chinook salmon in the lower Elwha River and estuary. These data represent baseline conditions of the ecosystem after nearly a century of changes due to the dams and will be useful in monitoring the changes to the river and estuary following dam removal.

  3. Simulated effects of dam removal on water temperatures along the Klamath River, Oregon and California, using 2010 Biological Opinion flow requirements

    Science.gov (United States)

    Risley, John C.; Brewer, Scott J.; Perry, Russell W.

    2012-01-01

    Computer model simulations were run to determine the effects of dam removal on water temperatures along the Klamath River, located in south-central Oregon and northern California, using flow requirements defined in the 2010 Biological Opinion of the National Marine Fisheries Service. A one-dimensional, daily averaged water temperature model (River Basin Model-10) developed by the U.S. Environmental Protection Agency Region 10, Seattle, Washington, was used in the analysis. This model had earlier been configured and calibrated for the Klamath River by the U.S. Geological Survey for the U.S. Department of the Interior, Klamath Secretarial Determination to simulate the effects of dam removal on water temperatures for current (2011) and future climate change scenarios. The analysis for this report was performed outside of the scope of the Klamath Secretarial Determination process at the request of the Bureau of Reclamation Technical Services Office, Denver, Colorado.For this analysis, two dam scenarios were simulated: “dams in” and “dams out.” In the “dams in” scenario, existing dams in the Klamath River were kept in place. In the “dams out” scenario, the river was modeled as a natural stream, without the J.C. Boyle, Copco1, Copco2, and Iron Gate Dams, for the entire simulation period. Output from the two dam scenario simulations included daily water temperatures simulated at 29 locations for a 50-year period along the Klamath River between river mile 253 (downstream of Link River Dam) and the Pacific Ocean. Both simulations used identical flow requirements, formulated in the 2010 Biological Opinion, and identical climate conditions based on the period 1961–2009.Simulated water temperatures from January through June at almost all locations between J.C. Boyle Reservoir and the Pacific Ocean were higher for the “dams out” scenario than for the “dams in” scenario. The simulated mean monthly water temperature increase was highest [1.7–2

  4. Removal of the dam sediments as a way of control of eutrophication. Eliminacion de los sedimentos en los embalses como medida de control de la eutrofizacion

    Energy Technology Data Exchange (ETDEWEB)

    Lacalle Pareja, B.; Gonzalez Garcia, P.; Pino Izquierdo, M.I.; Gomez Artola, C.

    1994-01-01

    It is raised the advantage of thinking over the utility of removing the dam sediments as a way of control of eutrophication, attending to the distribution and concentration in different points of bottom on three dams of the Community of Madrid destined to the human consume. Attending to the sediments dynamic and the geomorphological and climatic characteristics. (Author) 6 refs.

  5. Effects of dam removal on Tule Fall Chinook salmon spawning habitat in the White Salmon River, Washington

    Science.gov (United States)

    Hatten, James R.; Batt, Thomas R.; Skalicky, Joseph J.; Engle, Rod; Barton, Gary J.; Fosness, Ryan L.; Warren, Joe

    2016-01-01

    Condit Dam is one of the largest hydroelectric dams ever removed in the USA. Breached in a single explosive event in October 2011, hundreds-of-thousands of cubic metres of sediment washed down the White Salmon River onto spawning grounds of a threatened species, Columbia River tule fall Chinook salmon Oncorhynchus tshawytscha. We investigated over a 3-year period (2010–2012) how dam breaching affected channel morphology, river hydraulics, sediment composition and tule fall Chinook salmon (hereafter ‘tule salmon’) spawning habitat in the lower 1.7 km of the White Salmon River (project area). As expected, dam breaching dramatically affected channel morphology and spawning habitat due to a large load of sediment released from Northwestern Lake. Forty-two per cent of the project area that was previously covered in water was converted into islands or new shoreline, while a large pool near the mouth filled with sediments and a delta formed at the mouth. A two-dimensional hydrodynamic model revealed that pool area decreased 68.7% in the project area, while glides and riffles increased 659% and 530%, respectively. A spatially explicit habitat model found the mean probability of spawning habitat increased 46.2% after dam breaching due to an increase in glides and riffles. Shifting channels and bank instability continue to negatively affect some spawning habitat as sediments continue to wash downstream from former Northwestern Lake, but 300 m of new spawning habitat (river kilometre 0.6 to 0.9) that formed immediately post-breach has persisted into 2015. Less than 10% of tule salmon have spawned upstream of the former dam site to date, but the run sizes appear healthy and stable. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  6. Geomorphic and Salmon Habitat Response to Dam Removal with Minimal Constraints to Channel Evolution, Wa'atch Creek, Western Washington, U.S.A

    Science.gov (United States)

    Ritchie, A. C.; Shellberg, J. G.

    2010-12-01

    Dam removal has become an important component of aquatic ecosystem restoration, but studies documenting the physical and ecological response to dam removal across a range of human modified hydroclimatic and physiographic settings are still lacking. This research documents channel geomorphic response and fine sediment storage in salmon spawning gravels after removing two derelict dams (largest 6m) from Wa’atch Creek, located in the temperate coastal-marine zone of the Pacific Northwest, USA. After removing dam sheet pile and earthen fill, natural river processes including sediment flushing were allowed occur. Technical engineering solutions were avoided, unlike comparably sized dam removals in western Washington that over-engineered channel stability. However, two-hundred large-logs (LWD) were placed unanchored below the dam sites and throughout the reservoir before drawdown to sort and store sediment and provide future habitat complexity. Initial sedimentation impacts were severe following dam removal, temporarily smothering the bed of the creek with a fine sediment slurry (fluid mud) from dam to delta, killing aquatic biota, and covering spawning gravels with inhospitable levels of fine sediment. Subsequently, several large floods within the first year (max 10-yr recurrence interval) flushed the channel sediment slurry and over half (11,000 m^3) of the fine sediment stored in the reservoir out to sea. Coarse sediment aggraded immediately below the dam where wood was placed in the channel, while channel incision occurred through the reservoir and into tributaries, both diminishing away from the disturbance center. Channel changes were greatest immediately following removal due to high stream power, steep energy slope and saturated unconsolidated alluvium. The rate of change in sediment volume diminished over time (2003 to 2008) due to sediment consolidation, vegetation colonization, and a reduction in energy slope. After reservoir and channel flushing, fine

  7. Predicting spread of invasive exotic plants into de-watered reservoirs following dam removal on the Elwha River, Olympic National Park, Washington

    Science.gov (United States)

    Woodward, Andrea; Torgersen, Christian E.; Chenoweth, Joshua; Beirne, Katherine; Acker, Steve

    2011-01-01

    The National Park Service is planning to start the restoration of the Elwha River ecosystem in Olympic National Park by removing two high head dams beginning in 2011. The potential for dispersal of exotic plants into dewatered reservoirs following dam removal, which would inhibit restoration of native vegetation, is of great concern. We focused on predicting long-distance dispersal of invasive exotic plants rather than diffusive spread because local sources of invasive species have been surveyed. We included the long-distance dispersal vectors: wind, water, birds, beavers, ungulates, and users of roads and trails. Using information about the current distribution of invasive species from two surveys, various geographic information system techniques and models, and statistical methods, we identified high-priority areas for Park staff to treat prior to dam removal, and areas of the dewatered reservoirs at risk after dam removal.

  8. Combined Effects of Dam Removal and Past Sediment Mining on a Relatively Large Lowland Sandy Gravelly Bed River (Vienne River, France).

    Science.gov (United States)

    Rodrigues, S.; Ursache, O.; Bouchard, J. P.; Juge, P.

    2014-12-01

    Dam removal is of growing interest for the management of sediment fluxes, morphological evolution and ecological restoration of rivers. If dam removal experiments are well documented for small streams, examples of lowland and large rivers are scarce. We present the morphological response of a relatively large lowland river (Vienne River, France) to a dam removal. The objective is to understand and quantify the morphological adaptation on a reach of 50 km and over 15 years associated with the dam removal and the presence of ancient sand pits located along the riverbed. This study is based on field data collected during 7 surveys performed between 1998 and 2013. This dataset focuses on bed geometry, sediment grain size, and bedload fluxes. It was combined with a 1D numerical model to assess flow dynamics and sediment transport before and after dam removal. Results show that dam removal triggered both regressive and progressive erosions and that discharges higher than 100 m3.s-1 were sufficient to erode the sandy sediments trapped by the dam whereas gravels were mobilised for discharges higher than 300 m3.s-1. Since 1999, large bedload sediment waves coming from upstream migrated downstream at an average celerity of 2.2 km.year-1 and were trapped by three ancient sand pits located downstream. Some of these pits constitute efficient sediment traps even 15 years after dam removal. As a result, between 2002 and 2013, the slope of the river bed adjusted gently and observed morphological processes were minors compared with the time period between 1998 and 2002.

  9. Wildlife Impact Assessment and Summary of Previous Mitigation Related to Hydroelectric Projects in Montana, Volume One, Libby Dam Project, Operator, U.S. Army Corps of Engineers.

    Energy Technology Data Exchange (ETDEWEB)

    Yde, Chris A.

    1984-10-01

    This assessment addresses the impacts to the wildlife populations and wildlife habitats due to the Libby Dam project on the Kootenai River and previous mitigation of these losses. The current assessment documents the best available information concerning the impacts to the wildlife populations inhabiting the project area prior to construction of the dam and creation of the reservoir. Many of the impacts reported in this assessment differ from those contained in the earlier document compiled by the Fish and Wildlife Service; however, this document is a thorough compilation of the available data (habitat and wildlife) and, though conservative, attempts to realistically assess the impacts related to the Libby Dam project. Where appropriate the impacts resulting from highway construction and railroad relocation were included in the assessment. This was consistent with the previous assessments.

  10. A statistical analysis of dam removals in the United States of America%美国拆坝统计分析

    Institute of Scientific and Technical Information of China (English)

    李翠; 王晓玥

    2015-01-01

    The information found from researches regarding 1 093 removed dams across the United States from 1921 to 2013 is summarized. This paper analyzes information by the number, size, material and age of the removed dams and three primary dam removal purposes including environmental restora-tion, safety concerns, and economic considerations. The statistical results show that the dam removal phenomenon has existed for years and up to now the removed dams in the United States are small, low-head, aging and deteriorating dams. Dams that contribute a lot to the nation's economy are not removed at all, instead they get constant maintenance. Dams still form an integral part that makes great contribu-tion to the collective economy and social welfare.%对美国1921~2013年共计1 093座水坝拆除进行了信息统计,从拆坝数量、大坝规模、筑坝材料、坝龄等方面系统分析了美国拆坝现状,并从生态、经济、安全方面分析拆坝的主要原因.统计结果表明水坝拆除现象在美国一直存在,且至今为止美国所拆除的主要为小型水坝、旧坝、病险坝.对美国经济发展有重要影响的水坝不仅未被拆除,还不断得到维护,水坝在美国的经济和社会发展中仍贡献着重要力量.

  11. Northwest Montana Wildlife Mitigation Habitat Protection : Advance Design : Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Marilyn A.

    1993-02-01

    This report summarizes the habitat protection process developed to mitigate for certain wildlife and wildlife habitat losses due to construction of Hungry Horse and Libby dams in northwestern Montana.

  12. A riverscape perspective of Pacific salmonids and aquatic habitats prior to large-scale dam removal in the Elwha River, Washington, USA

    Science.gov (United States)

    Brenkman, S.J.; Duda, J.J.; Torgersen, C.E.; Welty, E.; Pess, G.R.; Peters, R.; McHenry, M.L.

    2012-01-01

     Dam removal has been increasingly proposed as a river restoration technique. In 2011, two large hydroelectric dams will be removed from Washington State’s Elwha River. Ten anadromous fish populations are expected to recolonise historical habitats after dam removal. A key to understanding watershed recolonisation is the collection of spatially continuous information on fish and aquatic habitats. A riverscape approach with an emphasis on biological data has rarely been applied in mid-sized, wilderness rivers, particularly in consecutive years prior to dam removal. Concurrent snorkel and habitat surveys were conducted from the headwaters to the mouth (rkm 65–0) of the Elwha River in 2007 and 2008. This riverscape approach characterised the spatial extent, assemblage structure and patterns of relative density of Pacific salmonids. The presence of dams influenced the longitudinal patterns of fish assemblages, and species richness was the highest downstream of the dams, where anadromous salmonids still have access. The percent composition of salmonids was similar in both years for rainbow trout, Oncorhynchus mykiss (Walbaum), coastal cutthroat trout, Oncorhynchus clarkii clarkii (Richardson) (89%; 88%), Chinook salmon, Oncorhynchus tshawytscha (Walbaum) (8%; 9%), and bull trout, Salvelinus confluentus (Suckley) (3% in both years). Spatial patterns of abundance for rainbow and cutthroat trout (r = 0.76) and bull trout (r = 0.70) were also consistent between years. Multivariate and univariate methods detected differences in habitat structure along the river profile caused by natural and anthropogenic factors. The riverscape view highlighted species-specific biological hotspots and revealed that 60–69% of federally threatened bull trout occurred near or below the dams. Spatially continuous surveys will be vital in evaluating the effectiveness of upcoming dam removal projects at restoring anadromous salmonids.

  13. A multiobjective optimization model for dam removal: an example trading off salmon passage with hydropower and water storage in the Willamette basin

    Science.gov (United States)

    Kuby, Michael J.; Fagan, William F.; ReVelle, Charles S.; Graf, William L.

    2005-08-01

    We introduce the use of systematic, combinatorial, multiobjective optimization models to analyse ecological-economic tradeoffs and to support complex decision-making associated with dam removal in a river system. The model's ecological objective enhances salmonid migration and spawning by maximizing drainage area reconnected to the sea. The economic objective minimizes loss of hydropower and storage capacity. We present a proof-of-concept demonstration for the Willamette River watershed (Oregon, USA). The case study shows a dramatic tradeoff in which removing twelve dams reconnects 52% of the basin while sacrificing only 1.6% of hydropower and water-storage capacity. Additional ecological gains, however, come with increasingly steeper economic costs. A second model incorporates existing fish-passage systems. Because of data limitations and model simplifications, these results are intended solely for the purpose of illustrating a novel application of multiobjective programming to dam-removal issues. Far more work would be needed to make policy-relevant recommendations. Nevertheless, this research suggests that the current practice of analysing dam-removal decisions on a dam-by-dam basis be supplemented by evaluation on a river-system basis, trading off economic and ecological goals.

  14. Stakeholders' frames and ecosystem service use in the context of a debate over rebuilding or removing a dam in New Brunswick, Canada

    Directory of Open Access Journals (Sweden)

    Kate H. Reilly

    2017-03-01

    Full Text Available As many dams are starting to reach the end of their life spans, discussions about whether they should be retained or removed are becoming more common. Such debates are often controversial, but little is known about stakeholders' opinions about the issue. We use frame theory to describe how stakeholders perceive a decision on the future of the Mactaquac Dam in New Brunswick, Canada. Frames describe how people make sense of a situation by determining what is important and inside the frame, and what is outside the frame, based on their past experiences and knowledge. We explore whether the benefits that people realize from ecosystems (ecosystem services influence their frames of dam removal. Based on interviews with 30 stakeholders, we found that participants who preferred to retain the dam aimed to prioritize the social and economic stability of the area, which relied on the ecosystem services provided by the dammed river. They emphasized the quality of the current ecosystem that has developed around the dam and preferred to avoid disturbing it. By contrast, those who preferred to remove the dam framed the decision as an opportunity to restore the ecology and social and economic activities that were present before the dam was built. These frames were influenced by participants' use of ecosystem services - both focus on the ecosystem services they use, while minimizing the benefits of others. Exploring frames allowed us to uncover the assumptions and biases implicit in their views, and identify topics for education campaigns as well as possible areas of agreement between parties. We conclude that ecosystem services are a relevant source of frames of a decision on a dam's future.

  15. Geomorphic response to large-dam removal: Impacts of a massive sediment release to the Elwha River, Washington

    Science.gov (United States)

    Magirl, C. S.; Ritchie, A.; Bountry, J.; Randle, T. J.; East, A. E.; Hilldale, R. C.; Curran, C. A.; Pess, G. R.

    2015-12-01

    The 2011-2014 staged removals of two nearly century-old dams on the Elwha River in northwest Washington State, the largest dam-removal project in the United States, exposed 21 million m3 of reservoir-trapped sand and gravel to potential fluvial transport. The river downstream from the dams is gravel bedded with a pool-riffle morphology. The river flows 20 km to the marine environment through a riparian corridor lined with large wood and having relatively few anthropogenic alterations. This moderately natural pre-dam-removal condition afforded an unprecedented opportunity to study river response to an anticipated massive sediment release. Four years into the project, 12 million m3 of sediment eroded from the former reservoirs with about 90% of the total load transported to the marine environment. Annualized sediment discharge was as great as 20 times the background natural load. Initial river response to the arrival of the first large sediment pulse was the nearly complete filling of the river's previously sediment-starved pools, widespread filling of side channels, and increased braiding index. In year 2, during maximum aggradation, the river graded to a plane-bedded system, efficiently conveying sediment to the marine environment. Modest peak flows (<2-yr return period) in year 2 promoted sediment transport but caused little large-scale geomorphic disturbance by channel migration or avulsions. As the river processed the sediment pulse, pools returned and the braiding index decreased in years 3-4. Higher peak flows in year 4 caused localized channel widening and migration but no major avulsions. Gauging indicated sand dominated the first stages of sediment release, but fluvial loads coarsened through time with progressive arrival of larger material. The literature suggests the Elwha River sediment wave should have evolved through dispersion with little translation. However, morphologic measurements and data from a stage-gauge network indicated patterns of

  16. Spawning migration movements of Lost River and shortnose suckers in the Williamson and Sprague Rivers, Oregon, following the removal of Chiloquin Dam-2009 Annual Report

    Science.gov (United States)

    Ellsworth, Craig M.; VanderKooi, Scott P.

    2011-01-01

    The Chiloquin Dam was located at river kilometer (rkm) 1.3 on the Sprague River near the town of Chiloquin, Oregon. The dam was identified as a barrier that potentially inhibited or prevented the upstream spawning migrations and other movements of endangered Lost River suckers (Deltistes luxatus), shortnose suckers (Chasmistes brevirostris), and other fish in the Sprague River. Our research objectives in 2009 were to evaluate adult catostomid spawning migration patterns using radio telemetry to identify and describe shifts in spawning area distribution and migration behavior following the removal of Chiloquin Dam in 2008. We attached external radio transmitters to 58 Lost River suckers and 59 shortnose suckers captured at the Williamson River fish weir. A total of 17 radio-tagged Lost River suckers and one radio-tagged shortnose sucker were detected approaching the site of the former Chiloquin Dam but only two radio-tagged fish (one male Lost River sucker and one female Lost River sucker) were detected crossing upstream of the dam site. A lower proportion of radio-tagged shortnose suckers were detected migrating into the Sprague River when compared with previous years. Detections on remote passive integrated transponder (PIT) tag arrays located in the Sprague River show that although the proportion of fish coming into the Sprague River is small when compared to the number of fish crossing the Williamson River fish weir, the number of fish migrating upstream of the Chiloquin Dam site increased exponentially in the first year since its removal. These data will be used in conjunction with larval production and adult spawning distribution data to evaluate the effectiveness of dam removal in order to provide increased access to underutilized spawning habitat located further upstream in the Sprague River and to reduce the crowding of spawning fish below the dam site.

  17. Synthesis of the effects to fish species of two management scenarios for the secretarial determination on removal of the lower four dams on the Klamath

    Science.gov (United States)

    Hamilton,; Rondorf, Dennis W.; Hampton,; Quinones,; Simondet,; Smith,

    2011-01-01

    For decades the long-standing conflict in the Klamath River Basin over water and fish resources has persisted. In an effort to resolve these disputes, PacifiCorp and interested parties negotiated, wrote, and signed the Klamath Hydroelectric Settlement Agreement (KHSA) in 2010, calling for the potential removal of the four lower dams on the Klamath River mainstem. The KHSA established a process known as the Secretarial Determination, which includes 1) conducting new scientific studies and a re-evaluation of existing studies found in the FERC record and from other sources, and 2) evaluating the potential environmental and human effects of such an action pursuant to National Environmental Policy Act, California Environmental Quality Act, and other applicable laws.  In March 2012, the Secretary of the Interior will decide whether removal of these dams on the Klamath River: 1) will advance salmonid fisheries, and 2) is in the public interest. In this report, we summarize anticipated effects to fish resources under two management scenarios: 1) current conditions with dams in place and without the programs and actions in the Klamath Basin Restoration Agreement (KBRA), and 2) removal of the lower four dams plus programs and actions called for in the KBRA and KHSA. This information will aid the Secretary of the Interior in determining whether dam removal and implementation of KBRA will advance restoration of salmonid (salmon and trout) fisheries.

  18. Recovery of sockeye salmon in the Elwha River, Washington, after dam removal: Dependence of smolt production on the resumption of anadromy by landlocked kokanee

    Science.gov (United States)

    Hansen, Adam G.; Gardner, Jennifer R.; Beauchamp, David A.; Paradis, Rebecca; Quinn, Thomas P

    2016-01-01

    Pacific salmon Oncorhynchus spp. are adept at colonizing habitat that has been reopened to anadromous passage. Sockeye Salmon O. nerka are unique in that most populations require lakes to fulfill their life history. Thus, for Sockeye Salmon to colonize a system, projects like dam removals must provide access to lakes. However, if the lakes contain landlocked kokanee (lacustrine Sockeye Salmon), the recovery of Sockeye Salmon could be mediated by interactions between the two life history forms and the processes associated with the resumption of anadromy. Our objective was to evaluate the extent to which estimates of Sockeye Salmon smolt production and recovery are sensitive to the resumption of anadromy by kokanee after dam removal. We informed the analysis based on the abiotic and biotic features of Lake Sutherland, which was recently opened to passage after dam removal on the Elwha River, Washington. We first developed maximum expectations for the smolt-producing capacity of Lake Sutherland by using two predictive models developed from Sockeye Salmon populations in Alaska and British Columbia: one model was based on the mean seasonal biomass of macrozooplankton, and the other was based on the euphotic zone volume of the lake. We then constructed a bioenergetics-based simulation model to evaluate how the capacity of Lake Sutherland to rear yearling smolts could change with varying degrees of anadromy among O. nerka fry. We demonstrated that (1) the smolt-producing capacity of a nursery lake for juvenile Sockeye Salmon changes in nonlinear ways with changes in smolt growth, mortality, and the extent to which kokanee resume anadromy after dam removal; (2) kokanee populations may be robust to changes in abundance after dam removal, particularly if lakes are located higher in the watershed on tributaries separate from where dams were removed; and (3) the productivity of newly establishing Sockeye Salmon can vary considerably depending on whether the population becomes

  19. 七里坝水库除险加固拱坝应力分析%Stress analysis of risk removal reinforcement arch dam in Qiliba Reservoir

    Institute of Scientific and Technical Information of China (English)

    李太军

    2015-01-01

    Qiliba Reservoir is located in mountain valley area,which has been operated for many years and belongs to dangerous reservoir.The arch dam belongs to thickened single arch dam on the downstream face.The dam body have transverse cracks and horizontal cracks.In the paper,arch dam stress is comparatively analyzed and studied.The reinforcement treatment plan of arch gravity dam is proposed.The conclusion of stable and safe arch dam after risk removal and reinforcement is obtained,and the operation results show that the dam is stable with safe operation.%七里坝水库处于高山峡谷地区,为运行多年的病险水库,拱坝为下游面加厚的单曲拱坝,坝体存在横向裂缝和水平裂缝,本文通过对拱坝应力进行对比分析研究,提出了拱型重力坝加固处理方案,得出了除险加固后拱坝稳定安全的结论,运行结果表明,大坝稳定、运行安全。

  20. Coastal habitats of the Elwha River, Washington- Biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    This report includes chapters that summarize the results of multidisciplinary studies to quantify and characterize the current (2011) status and baseline conditions of the lower Elwha River, its estuary, and the adjacent nearshore ecosystems prior to the historic removal of two long-standing dams that have strongly influenced river, estuary, and nearshore conditions. The studies were conducted as part of the U.S. Geological Survey Multi-disciplinary Coastal Habitats in Puget Sound (MD-CHIPS) project. Chapter 1 is the introductory chapter that provides background and a historical context for the Elwha River dam removal and ecosystem restoration project. In chapter 2, the volume and timing of sediment delivery to the estuary and nearshore are discussed, providing an overview of the sediment stored in the two reservoirs and the expected erosion mechanics of the reservoir sediment deposits after removal of the dams. Chapter 3 describes the geological background of the Olympic Peninsula and the geomorphology of the Elwha River and nearshore. Chapter 4 details a series of hydrological data collected by the MD-CHIPS Elwha project. These include groundwater monitoring, surface water-groundwater interactions in the estuary, an estimated surface-water budget to the estuary, and a series of temperature and salinity measurements. Chapter 5 details the work that has been completed in the nearshore, including the measurement of waves, tides, and currents; the development of a numerical hydrodynamic model; and a description of the freshwater plume entering the Strait of Juan de Fuca. Chapter 6 includes a characterization of the nearshore benthic substrate developed using sonar, which formed a habitat template used to design scuba surveys of the benthic biological communities. Chapter 7 describes the ecological studies conducted in the lower river and estuary and includes characterization of juvenile salmon diets and seasonal estuary utilization patterns using otolith analysis to

  1. Using Repeat LiDAR Surveys to Determine the Geomorphic Changes Related the Removal of the Marmot Dam on the Sandy River, Oregon

    Science.gov (United States)

    Matzek, C. D.; Ely, L. L.; O'Connor, J. E.

    2012-12-01

    The removal of the Marmot Dam on the Sandy River, Oregon in October 2007 released an estimated 430,000 m3 of sand and gravel downstream. Field surveys by Major and others (Major and others, USGS Professional Paper 1792) following the dam removal documented deposition of nearly half of the eroded sediment (215,000 m3) in the first 2 km downstream of the dam within a year of breaching. However, the fate of more than 200,000 m3 of chiefly sand transported farther downstream is uncertain. In the current study, five sequential LiDAR data sets from 2006 to 2011 were used to quantify sediment storage and erosion in the 40 km from the former dam site to the confluence with the Columbia River to track the downstream movement of the sediment released from the reservoir. We hypothesized that a pulse of sediment from the dam removal would be distinguished by a successive downstream growth of sediment bars through time. The LiDAR imagery includes two data sets acquired before the dam removal and three afterward. Geomorphic Change Detection software (GCD) (gcd.joewheaton.org) was used to quantify the locations and volume of sediment erosion and deposition through the successive years of LiDAR imagery. GCD allows for error assessment of each LiDAR-derived digital elevation map (DEM) and propagates the combined errors when differencing two repeat surveys. This process allows creation of DEM of Difference (DoD) maps with associated uncertainty estimates. Preliminary results of the LiDAR analysis agree with the previous field estimates of deposition within the first 2 km from the former dam. Following the initial phase of deposition immediately downstream of the dam breach, the subsequent surveys (2008-2011) show an erosional front beginning to migrate downstream through the newly deposited sediment. Many of the sediment bars still remained in 2011, but were reduced in size. After calibrating the model in the 2-km reach below the dam, we analyzed the additional 38 km of channel

  2. 实例探析大坝除险加固设计%Case Study of Dam Danger Removal and Reinforcement Design

    Institute of Scientific and Technical Information of China (English)

    杨田

    2014-01-01

    邓家沟水库大坝已经进入老龄阶段,加之在大坝设计、施工中存在一些问题,使得大坝工程存在各种问题。以邓家沟水库大坝工程为实例,采取全面分析→发现问题→分析问题→灵活选用技术方案→经济、技术比较→方案验证的技术路线,为大坝除险加固工作参考,选择出合适的大坝加固方案,并对加固措施进行有效的实施。%Dengjiagou reservoir dam has entered the aging stage,due to some problems in the dam design and construction;There are many problems for the dam engineering.Taking the dam of Dengjiagou reservoir as an example,the following technological route is adopted:comprehensive analysis-finding problems-analyzing problems-selecting technological scheme flexibly-economical and technological comparison-verified technological route.The technological route can be used for the reference of dam danger removal and reinforcement design,and choose suitable dam reinforcement scheme and reinforcement measures for effective implementation.

  3. Simulating the recovery of suspended sediment transport and river-bed stability in response to dam removal on the Elwha River, Washington

    Science.gov (United States)

    Konrad, C.P.

    2009-01-01

    U.S. Department of the Interior is planning to remove two high dams (30 and 60 m) from the Elwha River, which will allow the river to erode sediment deposits in the reservoirs, and ultimately restore the river ecosystem. Fluvial sediment transport and deposition paradoxically represent ecological disturbance and restoration. A one-dimensional, movable boundary sediment-transport model was applied at a daily time step to simulate changes in river-bed elevations and particle-size distributions and concentrations of suspended sediment. The simulations included a three-year dam removal period and a four-year recovery period. Simulated concentrations of suspended sediment recover rapidly during the recovery period. Simulated bed elevation and particle-size distributions are stable for much of the river during the recovery period, but high flows periodically disturb the river bed, causing changes in river-bed elevation and particle-size distribution, especially during autumn, when summer/autumn chinook salmon are incubating in redds. Although the river bed will become increasingly stable after dam removal, episodic high flows will interrupt recovery trends. Productivity and diversity of the ecosystem may be lower because of excess sediment immediately after dam removal but should increase during recovery above current levels as the river. Monitoring of the recovery of the Elwha River ecosystem can target ecologically significant physical parameters indicating the transition from a sediment transport-limited state to a supply-limited state.

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

    NARCIS (Netherlands)

    Poppl, R.; Coulthard, T.; Keesstra, S.D.; Keiler, M.

    2015-01-01

    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),

  5. An Analysis of the Reasons of Dam Removal in the United States%美国拆坝原因分析

    Institute of Scientific and Technical Information of China (English)

    王若男; 吴文强; 彭文启; 李树文

    2015-01-01

    闸坝建设可以有众多的理由,世界各国都争先恐后的建设闸坝。但闸坝的拆除却阻力重重,全球各地迄今为止,人工主动拆除的大中型闸坝几乎为零,中小型闸坝的拆除才刚刚起步。美国建设闸坝超过8.7万座,随着社会发展的需要,1912-2013年百余年间美国共拆除闸坝1108座,是世界上拆坝最多的国家。通过汇总分析,美国的拆坝原因可划分为5大类:生态修复、经济因素、安全保障、拆除重建和拆除违规建筑闸坝。其中,生态修复、经济因素、安全保障是美国拆坝的3个主要驱动因素,占到拆坝数量的97.9%。通过对美国拆坝主要原因进行分析,以实例的形式论述了生态、经济及安全因素如何成为美国拆坝的主要动因,对我国今后的拆坝工作具有宝贵的指导与借鉴意义。%There are so many reasons for building dams ,and building dams is a popular project throughout the world .But ,dam re‐moval is still confronted with lots of difficulties .People almost never take the initiative to remove large and medium-sized dams ,and the removal of small dams is just starting .The United States has more than 87 ,000 dams by now ,along with the needs of social de‐velopment ,this country removed 1 108 dams from 1912 to 2013 .Irrespective of the number and the research levels about dam re‐moval ,the U .S .is leading the position .The reasons for dam removal include ecological restoration ,cost-saving ,security ,rebuil‐ding ,and unauthorized dams ,among which ,ecology restoration ,cost-saving ,and security are the main driving factors ,which ac‐count for 97 .9% .An analysis of the reasons and typical cases of dam removal in the U .S .has some guidance and reference signifi‐cance to our future dam removal .

  6. Peace on the River? Social-Ecological Restoration and Large Dam Removal in the Klamath Basin, USA

    Directory of Open Access Journals (Sweden)

    Hannah Gosnell

    2010-06-01

    Full Text Available This paper aims to explain the multiple factors that contributed to a 2010 agreement to remove four large dams along the Klamath river in California and Oregon and initiate a comprehensive social-ecological restoration effort that will benefit Indian tribes, the endangered fish on which they depend, irrigated agriculture, and local economies in the river basin. We suggest that the legal framework, including the tribal trust responsibility, the Endangered Species Act, and the Federal Power Act, combined with an innovative approach to negotiation that allowed for collaboration and compromise, created a space for divergent interests to come together and forge a legally and politically viable solution to a suite of social and environmental problems. Improved social relations between formerly antagonistic Indian tribes and non-tribal farmers and ranchers, which came about due to a number of local collaborative processes during the early 2000s, were critical to the success of this effort. Overall, we suggest that recent events in the Klamath basin are indicative of a significant power shift taking place between tribal and non-tribal interests as tribes gain access to decision-making processes regarding tribal trust resources and develop capacity to participate in the development of complex restoration strategies.

  7. American shad migratory behavior, weight loss, survival, and abundance in a North Carolina River following dam removals

    Science.gov (United States)

    Raabe, Joshua K.; Hightower, Joseph E.

    2014-01-01

    Despite extensive management and research, populations of American Shad Alosa sapidissima have experienced prolonged declines, and uncertainty about the underlying mechanisms causing these declines remains. In the springs of 2007 through 2010, we used a resistance board weir and PIT technology to capture, tag, and track American Shad in the Little River, North Carolina, a tributary to the Neuse River with complete and partial removals of low-head dams. Our objectives were to examine migratory behaviors and estimate weight loss, survival, and abundance during each spawning season. Males typically immigrated earlier than females and also used upstream habitat at a higher percentage, but otherwise exhibited relatively similar migratory patterns. Proportional weight loss displayed a strong positive relationship with both cumulative water temperature during residence time and number of days spent upstream, and to a lesser extent, minimum distance the fish traveled in the river. Surviving emigrating males lost up to 30% of their initial weight and females lost up to 50% of their initial weight, indicating there are potential survival thresholds. Survival for the spawning season was low and estimates ranged from 0.07 to 0.17; no distinct factors (e.g., sex, size, migration distance) that could contribute to survival were detected. Sampled and estimated American Shad abundance increased from 2007 through 2009, but was lower in 2010. Our study provides substantial new information about American Shad spawning that may aid restoration efforts.

  8. Evaluation of groundwater-surface water interaction through groundwater modelling: simulation of the effects of removal of a dam along a river at a contaminated site in Northern France

    National Research Council Canada - National Science Library

    Remonti, Michele; Mori, Piero

    .... The scope of the work was the optimisation of the existing groundwater pump and treat system and the prediction of possible effects on groundwater circulation after the future removal of a dam located along the river...

  9. Short- to Medium-Term Geomorphic Response of the Souhegan River to the 2008 Removal of the Merrimack Village Dam in Southern New Hampshire

    Science.gov (United States)

    Snyder, N. P.; Collins, M. J.; Armistead, C. C.; Conlon, M.; David, G. C.; Lisius, G.; Lucy, C. O.; Munz, K. T.; Pearson, A.; Santaniello, D. J.

    2014-12-01

    Removing the Merrimack Village Dam on the lower Souhegan River (drainage area ~570 km2) in southern New Hampshire in August 2008 provided a field-scale experiment in river response to a major change in sediment flux and base level. We began monitoring the study area in August 2007, surveying a series of eight permanent cross sections within the impoundment and four downstream between the dam and the confluence with the Merrimack River (drainage area ~8,000 km2). We also surveyed the longitudinal profile through the 1-km study reach, measured bed grain size distribution, and photographed the site from ground-level stations. We conducted nine repeat surveys from 2008 to 2014, with the greatest frequency soon after dam removal. In 2012 and 2014, we also surveyed the former impoundment using low-altitude aerial photographs and structure-from-motion photogrammetry. The dam removal resulted in a near-instantaneous 3.9-m drop in base level in the impoundment. The river incised rapidly through the impounded sand and removed over 50% of it within the first two months. This added sediment load resulted in up to 3.2 m of deposition in the downstream reach. After the initial, rapid phase of channel adjustment, ongoing erosion of reservoir sediment depended primarily on flood events that could access sediment stored outside of the newly developed, active channel. By 2011, about 20% of the impounded sand remained, and this proportion was similar in the 2012 and 2014 surveys. The erosion process in the former impoundment was modulated by the recruitment of large wood (several 15-20 m tall trees with intact rootballs) from terraces through bank erosion, which remained stable in the channel and armored the banks. In the past two years, these trees have begun to be buried in newly deposited sediment, suggesting initiation of a floodplain large-wood cycle (Collins et al., 2012). At present, establishment of herbaceous vegetation on geomorphic surfaces is an important process

  10. A Bird's-eye View with X-ray Vision: Remote-sensing tools to Monitor Reach-scale Response to Dam Removal on the Elwha River

    Science.gov (United States)

    Ritchie, A. C.

    2012-12-01

    Repeat digital surface models, orthoimagery and sidescan sonar data are being generated to monitor river response to the largest dam removal and controlled sediment release in history on the Elwha River, on the Olympic Peninsula in Washington State. These products are generated using low-cost readily-available tools to collect data at a spatial and temporal scale that provides important insight into effects of base-level change, sediment release, and discrete hydrologic events on erosion of reservoir sediments, downstream sediment transport, and channel evolution above and below the dam sites. In combination, these products provide a view above and below the water surface to changes in sediment composition and morphology that other methods cannot capture at this spatial scale and both spatial and temporal resolution. Orthoimagery is developed from still images collected with a plane-mounted point-and-shoot camera using customized firmware from the open-source Canon Hack Development Kit (CHDK) with a total hardware cost of about $300 USD. Images are processed using structure-from-motion algorithms. Several software options are available. Sonar data are collected from a raft-mounted platform using a high-resolution 990 KHz Starfish sidescan sonar, with a water-resistant topside enclosure holding top-side electronics. A steerable pole-mount was developed for this application to allow the sidescan to to remain oriented in the direction of motion-over-ground.; Surface reconstruction from aerial images collected during Elwha dam removal project. ; bedforms near Elwha Sediment Treatment Plant from sediment released from Lake Aldwell, surveyed 12 July 2012.

  11. Vegetation of the Elwha River estuary: Chapter 8 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Shafroth, Patrick B.; Fuentes, Tracy L.; Pritekel, Cynthia; Beirne, Matthew M.; Beauchamp, Vanessa B.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    The Elwha River estuary supports one of the most diverse coastal wetland complexes yet described in the Salish Sea region, in terms of vegetation types and plant species richness. Using a combination of aerial imagery and vegetation plot sampling, we identified 6 primary vegetation types and 121 plant species in a 39.7 ha area. Most of the estuary is dominated by woody vegetation types, with mixed riparian forest being the most abundant (20 ha), followed by riparian shrub (6.3 ha) and willow-alder forest (3.9 ha). The shrub-emergent marsh transition vegetation type was fourth most abundant (2.2 ha), followed by minor amounts of dunegrass (1.75 ha) and emergent marsh (0.2 ha). This chapter documents the abundance, distribution, and floristics of these six vegetation types, including plant species richness, life form, species origin (native or introduced), and species wetland indicator status. These data will serve as a baseline to which future changes can be compared, following the impending removal of Glines Canyon and Elwha Dams upstream on the Elwha River. Dam removals may alter many of the processes, materials, and biotic interactions that influence the estuary plant communities, including hydrology, salinity, sediment and wood transport, nutrients, and plant-microbe interactions.

  12. The geomorphic legacy of small dams — An Austrian study

    NARCIS (Netherlands)

    Poeppl, R.E.; Keesstra, S.D.; Hein, T.

    2015-01-01

    Dams represent one of the most dominant forms of human impact upon fluvial systems during the Anthropocene, as they disrupt the downstream transfer of water and sediments. Removing dams restores river continuity and channel morphology. Both dam construction and dam removal induce geomorphic channel

  13. Dams (National)

    Data.gov (United States)

    Department of Transportation — This map layer portrays major dams of the United States, including Puerto Rico and the U.S. Virgin Islands (NTAD 2015). The map layer was created by extracting dams...

  14. Montana StreamStats

    Science.gov (United States)

    2016-04-05

    About this volumeMontana StreamStats is a Web-based geographic information system (http://water.usgs.gov/osw/streamstats/) application that provides users with access to basin and streamflow characteristics for gaged and ungaged streams in Montana. Montana StreamStats was developed by the U.S. Geological Survey (USGS) in cooperation with the Montana Departments of Transportation, Environmental Quality, and Natural Resources and Conservation. The USGS Scientific Investigations Report consists of seven independent but complementary chapters dealing with various aspects of this effort.Chapter A describes the Montana StreamStats application, the basin and streamflow datasets, and provides a brief overview of the streamflow characteristics and regression equations used in the study. Chapters B through E document the datasets, methods, and results of analyses to determine streamflow characteristics, such as peak-flow frequencies, low-flow frequencies, and monthly and annual characteristics, for USGS streamflow-gaging stations in and near Montana. The StreamStats analytical toolsets that allow users to delineate drainage basins and solve regression equations to estimate streamflow characteristics at ungaged sites in Montana are described in Chapters F and G.

  15. Fish population and habitat analysis in Buck Creek, Washington, prior to recolonization by anadromous salmonids after the removal of Condit Dam

    Science.gov (United States)

    Allen, M. Brady; Burkhardt, Jeanette; Munz, Carrie; Connolly, Patrick J.

    2012-01-01

    We assessed the physical and biotic conditions in the part of Buck Creek, Washington, potentially accessible to anadromous fishes. This creek is a major tributary to the White Salmon River upstream of Condit Dam, which was breached in October 2011. Habitat and fish populations were characterized in four stream reaches. Reach breaks were based on stream gradient, water withdrawals, and fish barriers. Buck Creek generally was confined, with a single straight channel and low sinuosity. Boulders and cobble were the dominant stream substrate, with limited gravel available for spawning. Large-cobble riffles were 83 percent of the available fish habitat. Pools, comprising 15 percent of the surface area, mostly were formed by bedrock with little instream cover and low complexity. Instream wood averaged 6—10 pieces per 100 meters, 80 percent of which was less than 50 centimeters in diameter. Water temperature in Buck Creek rarely exceeded 16 degrees Celsius and did so for only 1 day at river kilometer (rkm) 3 and 11 days at rkm 0.2 in late July and early August 2009. The maximum temperature recorded was 17.2 degrees Celsius at rkm 0.2 on August 2, 2009. Minimum summer discharge in Buck Creek was 3.3 cubic feet per second downstream of an irrigation diversion (rkm 3.1) and 7.7 cubic feet per second at its confluence with the White Salmon River. Rainbow trout (Oncorhynchus mykiss) was the dominant fish species in all reaches. The abundance of age-1 or older rainbow trout was similar between reaches. However, in 2009 and 2010, the greatest abundance of age-0 rainbow trout (8 fish per meter) was in the most downstream reach. These analyses in Buck Creek are important for understanding the factors that may limit fish abundance and productivity, and they will help identify and prioritize potential restoration actions. The data collected constitute baseline information of pre-dam removal conditions that will allow assessment of changes in fish populations now that Condit Dam has

  16. Geomorphology of the Elwha River and its Delta: Chapter 3 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Warrick, Jonathan A.; Draut, Amy E.; McHenry, Michael L.; Miller, Ian M.; Magirl, Christopher S.; Beirne, Matthew M.; Stevens, Andrew Stevens; Logan, Joshua B.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    The removal of two dams on the Elwha River will introduce massive volumes of sediment to the river, and this increase in sediment supply in the river will likely modify the shapes and forms of the river and coastal landscape downstream of the dams. This chapter provides the geologic and geomorphologic background of the Olympic Peninsula and the Elwha River with emphasis on the present river and shoreline. The Elwha River watershed was formed through the uplift of the Olympic Mountains, erosion and movement of sediment throughout the watershed from glaciers, and downslope movement of sediment from gravitational and hydrologic forces. Recent alterations to the river morphology and sediment movement through the river include the two large dams slated to be removed in 2011, but also include repeated bulldozing of channel boundaries, construction and maintenance of flood plain levees, a weir and diversion channel for water supply purposes, and engineered log jams to help enhance river habitat for salmon. The shoreline of the Elwha River delta has changed in location by several kilometers during the past 14,000 years, in response to variations in the local sea-level of approximately 150 meters. Erosion of the shoreline has accelerated during the past 80 years, resulting in landward movement of the beach by more than 200 meters near the river mouth, net reduction in the area of coastal wetlands, and the development of an armored low-tide terrace of the beach consisting primarily of cobble. Changes to the river and coastal morphology during and following dam removal may be substantial, and consistent, long-term monitoring of these systems will be needed to characterize the effects of the dam removal project.

  17. Composition and Relative Abundance of Fish Species in the Lower White Salmon River, Washington, Prior to the Removal of Condit Dam

    Science.gov (United States)

    Allen, M. Brady; Connolly, Patrick J.

    2011-01-01

    Information about the composition and relative abundance of fish species was collected by a rotary screw trap and backpack electrofishing in the lower White Salmon River, Washington. The information was collected downstream of Condit Dam, which is at river kilometer (rkm) 5.2, and is proposed for removal in October 2011. A rotary screw trap was installed in the White Salmon River at rkm 1.5 and operated from March through June during 2006-09. All captured fish were identified to species and enumerated. Daily subsets of fish were weighed, measured, and fin clipped for a genetic analysis by the U.S. Fish and Wildlife Service. *Fall Chinook salmon (Oncorhynchus tshawytscha) were captured in the highest numbers (n=18, 640), and were composed of two stocks: tule and upriver bright. Almost all captured fall Chinook salmon were age-0, with only 16 (0.09 percent) being age-1 or older. *Tule fall Chinook salmon, the native stock, generally out-migrated from mid-March through early April. The tule stock was the more abundant fall Chinook salmon subspecies, comprising 85 percent of those captured in the trap. *Upriver bright fall Chinook salmon comprised 15 percent of the Chinook salmon catch and generally out-migrated from late May to early June. *Coho salmon (O. kisutch) and steelhead trout (O. mykiss) were captured by the rotary screw trap in all years. Coho salmon were caught in low numbers (n=661) and 69 percent were age-0 fish. Steelhead were slightly more abundant (n=679) than coho salmon and 84 percent were age-1 or older fish. Trap efficiency estimates varied widely (range, 0-10 percent) by species, fish size, and time of year. However, if we use only the estimates from efficiency tests where more than 300 wild age-0 Chinook salmon were released, there was a mean trapping efficiency of 1.4 percent (n=4, median, 1.3 percent, range, 0.3-2.4 percent) during the tule out-migration period, and a mean trapping efficiency of 0.8 percent (n=2, range, 0.3-1.2 percent) during

  18. Coastal processes of the Elwha River delta: Chapter 5 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Warrick, Jonathan A.; Stevens, Andrew W.; Miller, Ian M.; Gelfenbaum, Guy; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    To understand the effects of increased sediment supply from dam removal on marine habitats around the Elwha River delta, a basic understanding of the region’s coastal processes is necessary. This chapter provides a summary of the physical setting of the coast near the Elwha River delta, for the purpose of synthesizing the processes that move and disperse sediment discharged by the river. One fundamental property of this coastal setting is the difference between currents in the surfzone with those in the coastal waters offshore of the surfzone. Surfzone currents are largely dictated by the direction and size of waves, and the waves that attack the Elwha River delta predominantly come from Pacific Ocean swell from the west. This establishes surfzone currents and littoral sediment transport that are eastward along much of the delta. Offshore of the surfzone the currents are largely influenced by tidal circulation and the physical constraint to flow provided by the delta’s headland. During both ebbing and flooding tides, the flow separates from the coast at the tip of the delta’s headland, and this produces eddies on the downstream side of the headland. Immediately offshore of the Elwha River mouth, this creates a situation in which the coastal currents are directed toward the east much more frequently than toward the west. This suggests that Elwha River sediment will be more likely to move toward the east in the coastal system.

  19. Forest regions of Montana

    Science.gov (United States)

    Stephen F. Arno

    1979-01-01

    In this paper, Montana is divided into eight geographic subdivisions called "forest regions," based on distributions of tree and undergrowth species and the relationship of these patterns to climate and topography. The regions serve as a geographic reference for describing patterns of forest vegetation across the State. Data on the distributions of plant...

  20. Arnica montana L

    NARCIS (Netherlands)

    Andreas, Ch.H.

    1958-01-01

    Een eventuele veelvormigheid van de wolverlei, Arnica montana L., heeft in ons land, voor zover mij bekend, geen aanleiding gegeven tot een onderverdeling dezer soort. In Portugal is dat wel het geval; A. de Bolos beschreef in 1948 in het tijdschrift Agronomia Lusitanica 2 ondersoorten voor het Iber

  1. Building Footprints - Montana Structures/Addresses Framework

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Montana Structures/Addresses Framework is a statewide spatial database of structure and address points in the State of Montana. The Montana Structures/Addresses...

  2. Patterns of Larval Sucker Emigration from the Sprague and Lower Williamson Rivers of the Upper Klamath Basin, Oregon, Prior to the Removal of Chiloquin Dam - 2006 Annual Report

    Science.gov (United States)

    Ellsworth, Craig M.; Tyler, Torrey J.; VanderKooi, Scott P.; Markle, Douglas F.

    2009-01-01

    In 2006, we collected larval Lost River sucker Deltistes luxatus (LRS), shortnose sucker Chasmistes brevirostris (SNS), and Klamath largescale sucker Catostomus snyderi (KLS) emigrating from spawning areas in the Williamson and Sprague Rivers. This work is part of a multi-year effort to characterize the relative abundance, drift timing, and length frequencies of larval suckers in this watershed prior to the removal of Chiloquin Dam on the lower Sprague River. Additional larval drift samples were collected from the Fremont Bridge on Lakeshore Drive on the south end of Upper Klamath Lake near its outlet to the Link River. Because of difficulties in distinguishing KLS larvae from SNS larvae, individuals identified as either of these two species were grouped together and reported as KLS-SNS in this report. We found that larval densities varied by site with the highest densities being collected at the most upstream site on the Sprague River at river kilometer (rkm) 108.0 near Beatty, Oregon (Beatty), and the most downstream sites near Chiloquin, Oregon; one site on the Sprague River at rkm 0.7 (Chiloquin) and the other site on the Williamson River at rkm 7.4 (Williamson). Larval catches were relatively small and sporadic at two other sites on the Sprague River located between Chiloquin and Beatty (Power Station at rkm 9.5 and Lone Pine at rkm 52.7) and one site on the Sycan River at rkm 4.7. Most larvae (79 percent) collected in 2006 were identified as LRS. More larvae and eggs were collected at Chiloquin than at any other site. The seasonal timing of larval drift varied by location; larvae generally were captured earlier at upstream sites than at downstream sites. Cumulative catch percentages of drifting larvae suggest that larval LRS emigrated earlier than KLS-SNS larvae at every site. Drift of LRS larvae at Beatty began 3 to 4 weeks earlier than at Chiloquin or Williamson. At Chiloquin, peak larval catches occurred 3 and 5 weeks after peak egg catches. The daily peak

  3. Social Organization in Montana. Montana Economic Study-Staff Study.

    Science.gov (United States)

    Bigart, Robert J.

    The four papers in this publication discusses Montana's social structure as it relates to culture, income, urbanism, and communal religious communities. "Montana Social Structure and Culture" includes rural and suburban life styles; the history of rural community organization; rural-small town communities; urban physical conditions;…

  4. Dam Safety Concepts

    NARCIS (Netherlands)

    Duricic, J.

    2014-01-01

    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced techno

  5. Dam Safety Concepts

    NARCIS (Netherlands)

    Duricic, J.

    2014-01-01

    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced

  6. Dam Safety Concepts

    NARCIS (Netherlands)

    Duricic, J.

    2014-01-01

    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced techno

  7. Three Years Measuring Sediment Erosion and Deposition from the Largest Dam Removal Ever at Weekly-­to-­Monthly Scales Using SfM: Elwha River, Washington, USA.

    Science.gov (United States)

    Ritchie, A.; Randle, T. J.; Bountry, J.; Warrick, J. A.

    2015-12-01

    The stepwise removal of two dams on the Elwha River beginning in September 2011 exposed ~21 million cubic meters of sediment to fluvial erosion and created an unprecedented opportunity to monitor reservoir sediment erosion and river evolution during base level adjustment and a pulsed sediment release. We have conducted more than 60 aerial surveys with a Cessna 172 using a simple custom wing-mount for consumer grade cameras and SfM photogrammetry to produce orthoimagery and digital elevation models in near-real-time at weekly to monthly time intervals. Multiple lidar flights and ground survey campaigns have provided estimates of both systematic and random error for this uniquely dense dataset. Co-registration of multiple surveys during processing reduces systematic error and allows boot-strapping of subsequently established ground control to earlier flights. Measurements chronicle the erosion of 12 million cubic meters of reservoir sediment and record corresponding changes in channel braiding, wood loading and bank erosion. These data capture reservoir and river channel responses to dam removal at resolutions comparable to hydrologic forcing events, allowing us to quantify reservoir sediment budgets on a per-storm basis. This allows for the analysis of sediment transported relative to rates of reservoir drawdown and river stream power for dozens of intervals of time. Temporal decoupling of peak sediment flux and bank erosion rates is noted from these analyses. This dataset illustrates some of the challenges and opportunities emerging with the advent of big data in remote sensing of earth surface processes.

  8. Quantification of Libby Reservoir Levels Needed to Maintain or Enhance Reservoir Fisheries, 1990-1994 Investigations of Fish Entrainment Through Libby Dam.

    Energy Technology Data Exchange (ETDEWEB)

    Skaar, Don

    1996-01-01

    We investigated fish entrainment through Libby Dam from December 1990 to June 1994. This study was one portion of the effort by the Montana Department of Fish, Wildlife and Parks to quantify Libby Dam operations necessary to maintain or enhance Libby Reservoir fisheries.

  9. 基于朱隈水库大坝的除险加固措施研究%Research on risk removal reinforcement measures based on Zhuwei Reservoir dam

    Institute of Scientific and Technical Information of China (English)

    孙秀玲

    2016-01-01

    水库大坝病害造成的工程事故屡见不鲜,因此对水库大坝病害除险工作的研究显得尤为重要。本文结合工程地质情况,分析了朱隈水库大坝病害特征,提出了三种不同施工设计方案,通过优化设计确定最终的施工方案,并对关键技术进行了分析。工后显示,钢筋混凝土面板强度和抗渗等级都达到了预定目标,渗流量平均降幅超过85%,达到了良好的效果。%Engineering accidents caused by reservoir dam diseases are frequent.Therefore,it is very important to study risk removal work aiming at diseases in the reservoir dam.In the paper,engineering geological condition is combined for analyzing disease features of Zhuwei Reservoir Dam.Three different construction design plans are proposed.The final construction plan is determined through optimizing design.Key techniques are analyzed.Post-work result shows that the strength and anti-seepage grade of reinforced concrete slabs reach anticipated target.The seepage flow is averagely dropped by more than 85% with good effect.

  10. Limnological Investigations: Lake Koocanusa, Montana. Part 4. Factors Controlling Primary Productivity.

    Science.gov (United States)

    1982-06-01

    Lund (1965), Hutchinson (1967), Fogg (1975) and Wetzel (1975). Stadelmann et al. (1974) reported that the spring increase in primary productivity at a...Bighorn Lake-Yellowtail Dam, Montana. U.S.A. Freshwater Biology, vol. 5, p. 407-421. Stadelmann , P., J. E. Moore and E. Pickett (1974) Primary production...loading concept in limnology. Schweizerische Zeitschrift fur Hydrologic, vol. 37, p. 53-84. Vollenweider, R. A., M. Munawar and P. Stadelmann (1974) A

  11. Libraries in Montana: MedlinePlus

    Science.gov (United States)

    ... this page: https://medlineplus.gov/libraries/montana.html Libraries in Montana To use the sharing features on ... page, please enable JavaScript. Billings Billings Clinic Medical Library 2825 8th Avenue North Billings, MT 59107-5100 ...

  12. 78 FR 10507 - Montana Regulatory Program

    Science.gov (United States)

    2013-02-14

    ... approved pursuant to 30 CFR 732.17. Therefore, Montana advised that the minor grammatical changes will not.... Montana proposes changes to the Montana Strip and Underground Mine Reclamation Act (MSUMRA) that... conditions of approval in the April 1, 1980, Federal Register (45 FR 21560). You can also find later...

  13. MONTANA PALLADIUM RESEARCH INITIATIVE

    Energy Technology Data Exchange (ETDEWEB)

    Peters, John; McCloskey, Jay; Douglas, Trevor; Young, Mark; Snyder, Stuart; Gurney, Brian

    2012-05-09

    Project Objective: The overarching objective of the Montana Palladium Research Initiative is to perform scientific research on the properties and uses of palladium in the context of the U.S. Department of Energy's Hydrogen, Fuel Cells and Infrastructure Technologies Program. The purpose of the research will be to explore possible palladium as an alternative to platinum in hydrogen-economy applications. To achieve this objective, the Initiatives activities will focus on several cutting-edge research approaches across a range of disciplines, including metallurgy, biomimetics, instrumentation development, and systems analysis. Background: Platinum-group elements (PGEs) play significant roles in processing hydrogen, an element that shows high potential to address this need in the U.S. and the world for inexpensive, reliable, clean energy. Platinum, however, is a very expensive component of current and planned systems, so less-expensive alternatives that have similar physical properties are being sought. To this end, several tasks have been defined under the rubric of the Montana Palladium Research Iniative. This broad swath of activities will allow progress on several fronts. The membrane-related activities of Task 1 employs state-of-the-art and leading-edge technologies to develop new, ceramic-substrate metallic membranes for the production of high-purity hydrogen, and develop techniques for the production of thin, defect-free platinum group element catalytic membranes for energy production and pollution control. The biomimetic work in Task 2 explores the use of substrate-attached hydrogen-producing enzymes and the encapsulation of palladium in virion-based protein coats to determine their utility for distributed hydrogen production. Task 3 work involves developing laser-induced breakdown spectroscopy (LIBS) as a real-time, in situ diagnostic technique to characterize PGEs nanoparticles for process monitoring and control. The systems engineering work in task 4

  14. Streamflow characteristics based on data through water year 2009 for selected streamflow-gaging stations in or near Montana: Chapter E in Montana StreamStats

    Science.gov (United States)

    McCarthy, Peter M.

    2016-04-05

    Chapter E of this Scientific Investigations Report documents results from a study by the U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality and the Montana Department of Natural Resources and Conservation, to provide an update of statewide streamflow characteristics based on data through water year 2009 for streamflow-gaging stations in or near Montana. Streamflow characteristics are presented for 408 streamflow-gaging stations in Montana and adjacent areas having 10 or more years of record. Data include the magnitude and probability of annual low and high streamflow, the magnitude and probability of low streamflow for three seasons (March–June, July–October, and November–February), streamflow duration statistics for monthly and annual periods, and mean streamflows for monthly and annual periods. Streamflow is considered to be regulated at streamflow-gaging stations where dams or other large-scale human modifications affect 20 percent or more of the contributing drainage basin. Separate streamflow characteristics are presented for the unregulated and regulated periods of record for streamflow-gaging stations with sufficient data.

  15. Study on joint regulation of reservoirs in danger-removal and treatment of dammed lake%水库联合调度在堰塞湖排险处置中的作用研究

    Institute of Scientific and Technical Information of China (English)

    王绍志; 舒远华; 郞学友

    2015-01-01

    2014年8月3日,云南鲁甸县6. 5级强震在牛栏江干流形成了大型堰塞湖,应急排险和处置施工的难度较大. 基于干、支流多个水文监测点的观测数据,对牛栏江已建的4个水库、电站实施了联合调度. 利用上游德泽水库实施洪水拦蓄并削减洪峰,有效减少了堰塞湖的防洪压力. 对小岩头电站实施严格管理,遇特殊水情时保持上游来水与下泄水量一致. 对下游天花板电站、黄角树电站实行空库度汛,确保溃坝险情出现时具备拦洪功能. 经过6次联合调度以及3个多月的后续处置,有效减小了堰塞湖上、下游防洪压力,保障了下游沿岸集镇安全.%6. 5 magnitude Ludian earthquake struck Ludian County, Yunnan Province on 3 August in 2014 and generated a large scaled dammed lake on the mainstream of Niulan River, bringing along difficulties for the emergency danger-removal and treatment. On the basis of the measured data of multiple hydrological stations on stem Niulanjiang River, a joint regulation scheme containing 4 reservoirs was conducted. The flood control pressure of the dammed lake was mitigated by using upstream Deze Reservoir to retain the flood and reduce the peak. The strict regulation on Xiaoyantou Hydropower Station is to make the in-coming discharge equal to the releasing discharge under special water regime. Tianhuaban Hydropower Station and Huangjiaoshu Hydropower Station in downstream were emptied to ensure their flood storage function in dam break situation. After 6 times of joint regulation and the following up treatment for 3 months, the flood control pressure was reduced effectively and the safety of downstream area was guaranteed.

  16. Evaluation of groundwater-surface water interaction through groundwater modelling: simulation of the effects of removal of a dam along a river at a contaminated site in Northern France

    Directory of Open Access Journals (Sweden)

    Michele Remonti

    2013-06-01

    Full Text Available A numerical groundwater flow model has been developed for an industrial site bounded by a river in in Basse Normandie, Northern France. The scope of the work was the optimisation of the existing groundwater pump and treat system and the prediction of possible effects on groundwater circulation after the future removal of a dam located along the river. The model has been implemented with the finite difference code MODFLOW 2005 and represents an area with an extension of approximately 800 x 500 m. It has been calibrated using static conditions groundwater head data (wells deactivated and verified with 1 abstracting conditions (wells abstracting head data, 2 simulating pumping tests with transient simulations and 3 comparing measured average river baseflow with modelled river drainage. The model indicates that the hydraulic barrier in the present abstraction scenario has some problematic areas and needs some improvements, as confirmed by the hydrochemical data of the river water. A first predictive scenario has been developed to optimise the barrier, indicating that a flow rate of 0.5 m3/h each at three new barrier wells, in addition to the present abstraction scenario, should ensure the hydraulic containment of the site. A second predictive scenario simulates the optimised groundwater abstractions without the presence of the dam along the neighbouring river. In these conditions, the river will increase the drainage effect on the aquifer, requiring a further increase in the rate of abstraction from the existing and new wells to ensure the hydraulic containment. With this paper we would like to present an example of what we think is a correct professional approach, with the design of the simplest model as possible depending on the hydrogeological conceptual model complexity, the abundance of data and the model objectives, and where multiple confirmations of the correctness of groundwater model results have been searched for.

  17. Alpine dams

    Directory of Open Access Journals (Sweden)

    Alain Marnezy

    2009-03-01

    Full Text Available Les barrages-réservoirs de montagne ont été réalisés initialement dans les Alpes pour répondre à la demande d’énergie en période hivernale. Une certaine diversification des usages de l’eau s’est ensuite progressivement développée, en relation avec le développement touristique des collectivités locales. Aujourd’hui, la participation des ouvrages d’Électricité De France à la production de neige de culture représente une nouvelle étape. Dans les régions où les aménagements hydroélectriques sont nombreux, les besoins en eau pour la production de neige peuvent être résolus par prélèvements à partir des adductions EDF. Les gestionnaires de stations échappent ainsi aux inconvénients liés à la construction et à la gestion des « retenues collinaires ». Cette évolution, qui concerne déjà quelques régions alpines comme la haute Maurienne ou le Beaufortin, apparaît comme une forme renouvelée d’intégration territoriale de la ressource en eau.Mountain reservoirs were initially built in the Alps to meet energy needs in the winter. A certain diversification in the uses of water then gradually developed, related to tourism development in the local communities. Today, the use of facilities belonging to EDF (French Electricity Authority to provide water for winter resorts to make artificial snow represents a new phase. By taking water from EDF resources to supply snow-making equipment, resort managers are thus able to avoid the problems related to the construction and management of small headwater dams. This new orientation in the use of mountain water resources already affects a number of alpine regions such as the Upper Maurienne valley and Beaufortain massif and represents a renewed form of the territorial integration of water resources.

  18. Iran funds dam completion

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Iran has signed a contract with unnamed foreign financiers for US$300M to fund two half-finished dam schemes, according to Tehran radio. The schemes are the Ostur dam in Mianeh in East Azerbaijan province and the Molla Sadra dam in Fars province. The Ostur dam will have a storage capacity of 2B m3 and a 160 MW hydro power station.

  19. Hoover Dam Learning Packet.

    Science.gov (United States)

    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…

  20. Wetlands & Deepwater Habitats - Montana Wetland and Riparian Framework - Map Service

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Montana Wetland and Riparian Framework represents the extent, type, and approximate location of wetlands, riparian areas, and deepwater habitats in Montana....

  1. DOLUS LAKES ROADLESS AREA, MONTANA.

    Science.gov (United States)

    Elliott, James E.; Avery, Dale W.

    1984-01-01

    A mineral survey of the Dolus Lakes Roadless Area in southwestern Montana, was conducted. Much of the roadless area has probable and substantiated potential for resources of gold, silver, molybdenum, and tungsten. The nature of the geologic terrain indicates that there is little promise for the occurrence of coal, oil, gas, or geothermal resources. Detailed geologic and geochemical studies are suggested to delineate exploration targets that could be tested by drilling.

  2. Water-quality trends and constituent-transport analysis for selected sampling sites in the Milltown Reservoir/Clark Fork River Superfund Site in the upper Clark Fork Basin, Montana, water years 1996–2015

    Science.gov (United States)

    Sando, Steven K.; Vecchia, Aldo V.

    2016-07-20

    During the extended history of mining in the upper Clark Fork Basin in Montana, large amounts of waste materials enriched with metallic contaminants (cadmium, copper, lead, and zinc) and the metalloid trace element arsenic were generated from mining operations near Butte and milling and smelting operations near Anaconda. Extensive deposition of mining wastes in the Silver Bow Creek and Clark Fork channels and flood plains had substantial effects on water quality. Federal Superfund remediation activities in the upper Clark Fork Basin began in 1983 and have included substantial remediation near Butte and removal of the former Milltown Dam near Missoula. To aid in evaluating the effects of remediation activities on water quality, the U.S. Geological Survey began collecting streamflow and water-quality data in the upper Clark Fork Basin in the 1980s.Trend analysis was done on specific conductance, selected trace elements (arsenic, copper, and zinc), and suspended sediment for seven sampling sites in the Milltown Reservoir/Clark Fork River Superfund Site for water years 1996–2015. The most upstream site included in trend analysis is Silver Bow Creek at Warm Springs, Montana (sampling site 8), and the most downstream site is Clark Fork above Missoula, Montana (sampling site 22), which is just downstream from the former Milltown Dam. Water year is the 12-month period from October 1 through September 30 and is designated by the year in which it ends. Trend analysis was done by using a joint time-series model for concentration and streamflow. To provide temporal resolution of changes in water quality, trend analysis was conducted for four sequential 5-year periods: period 1 (water years 1996–2000), period 2 (water years 2001–5), period 3 (water years 2006–10), and period 4 (water years 2011–15). Because of the substantial effect of the intentional breach of Milltown Dam on March 28, 2008, period 3 was subdivided into period 3A (October 1, 2005–March 27, 2008

  3. Travel times, streamflow velocities, and dispersion rates in the Missouri River upstream from Canyon Ferry Lake, Montana

    Science.gov (United States)

    Whiteman, Aroscott

    2012-01-01

    In 2010, the U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality, initiated a dye-tracer study to determine travel times, streamflow velocities, and longitudinal dispersion rates for the Missouri River upstream from Canyon Ferry Lake. For this study, rhodamine WT (RWT) dye was injected at two locations, Missouri River Headwaters State Park in early September and Broadwater-Missouri Dam (Broadwater Dam) in late August 2010. Dye concentrations were measured at three sites downstream from each dye-injection location. The study area was a 41.2-mile reach of the Missouri River from Trident, Montana, at the confluence of the Jefferson, Madison, and Gallatin Rivers (Missouri River Headwaters) at river mile 2,319.40 downstream to the U.S. Route 12 Bridge (Townsend Bridge), river mile 2,278.23, near Townsend, Montana. Streamflows were reasonably steady and ranged from 3,070 to 3,700 cubic feet per second. Mean velocities were calculated for each subreach between measurement sites for the leading edge, peak concentration, centroid, and trailing edge at 10 percent of the peak concentration of the dye plume. Calculated velocities for the centroid of the dye plume ranged from 0.80 to 3.02 feet per second within the study reach from Missouri River Headwaters to Townsend Bridge, near Townsend. The mean velocity of the dye plume for the entire study reach, excluding the subreach between the abandoned Milwaukee Railroad bridge at Lombard, Montana (Milwaukee Bridge) and Broadwater-Missouri Dam (Broadwater Dam), was 2.87 feet per second. The velocity of the centroid of the dye plume for the subreach between Milwaukee Bridge and Broadwater Dam (Toston Reservoir) was 0.80 feet per second. The residence time for Toston Reservoir was 8.2 hours during this study. Estimated longitudinal dispersion rates of the dye plume for this study ranged from 0.72 feet per second for the subreach from Milwaukee Bridge to Broadwater Dam to 2.26 feet per second for

  4. 关河水库除险加固中大坝渗流监测系统的优化%Optimizing Dam Seepage Flow Monitoring System in Danger-removing and Consolidating Project of Guanhe Reservoir

    Institute of Scientific and Technical Information of China (English)

    张竞竞

    2012-01-01

    According to anti-thunderstroke capacity of seepage flow monitoring system , this system's lifespan , average failure-free operation time , construction management and investment condition , in combination with the ac-tual practice in danger-removing and consolidating project of Guanhe Reservoir , the comparison between wire moni-toring scheme and wireless monitoring scheme of dam seepage flow is carried out . The comparision result indicates that developing dam's wireless monitoring system is the general prevailing trend nowadays.%根据渗流监测系统抗雷击的能力、系统寿命和平均无故障时间、施工管理、投资等条件,结合关河水库工程的具体实际,对大坝渗流有线监测方案和无线监测方案进行比较,表明开发大坝无线监测系统已是大势所趋。

  5. Application of New Removable Filter Drainpipe to Gate Dam%新型可装卸反滤排水管在水闸工程中的应用

    Institute of Scientific and Technical Information of China (English)

    许思群

    2016-01-01

    Filter drainpipe is the key section to water conservancy infrastructure.Based on engineering practice in Da’ao gate dam, a new-designed removable filter drainpipe is easy and simple for disassembling and cleaning, which solves difficult problems of silt.Test results show that the drainpipe can effectively discharge the seepage and reduce the uplift pressure of the project.Mean-while, the new drainpipe is suitable for industrial production, controllable quality, easy maintenance, and more conducive to project management.%反虑排水设施在水利工程中往往是关键部位。大坳拦河闸坝结合工程实际,创新设计了一款便于装卸、清洗的反滤排水管,解决了排水管淤堵的难题。试运行表明,这种排水管能有效排出工程渗流,降低工程扬压力;同时,该新型排水管适合工业化生产,质量可控,维护方便,更有利于工程管理。

  6. 76 FR 47637 - Montana Disaster #MT-00062

    Science.gov (United States)

    2011-08-05

    ... ADMINISTRATION Montana Disaster MT-00062 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Montana (FEMA..., Fort Worth, TX 76155. FOR FURTHER INFORMATION CONTACT: A. Escobar, Office of Disaster Assistance,...

  7. 77 FR 47907 - Montana Disaster #MT-00067

    Science.gov (United States)

    2012-08-10

    ... ADMINISTRATION Montana Disaster MT-00067 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of MONTANA dated 08/02/2012. Incident: Ash Creek Fire. Incident Period: 06/25/2012 through 07/22/2012. Effective Date:...

  8. 77 FR 48198 - Montana Disaster #MT-00068

    Science.gov (United States)

    2012-08-13

    ... ADMINISTRATION Montana Disaster MT-00068 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Montana dated 08/06/2012. Incident: Dahl Fire. Incident Period: 06/26/2012 through 07/06/2012. Effective Date:...

  9. Dam to the Rescue

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Three Gorges Dam relieves the summer drought in south and central China,but may contribute to other problems The Three Gorges Dam played an important role in relieving China’s drought in central and eastern prov-inces that had been using increased water discharges from the Dam to irrigate dry farmlands facing the worst drought int he last 60 years in 2011.

  10. Past, Present, and Future Nutrient Quality of a Small Southeastern River: A Pre-Dam Assessment

    OpenAIRE

    Stewart, Paul M.; Miller, Jonathan M

    2013-01-01

    Riverine dams alter both the physical environment and water chemistry, thus affecting species assemblages within these environments. In the United States, dam construction is on the decline and there is a growing trend for dam removal. The Choctawhatchee, Pea, and Yellow Rivers Watershed Management Authority had initiated the permitting process for placing a reservoir dam on the Little Choctawhatchee River (LCR), a tributary to the Choctawhatchee River. The purpose of the proposed reservoir w...

  11. Hungry Horse Dam Fisheries Mitigation; Kokanee Stocking and Monitoring in Flathead Lake, 1995 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Fredenberg, Wade; Carty, Daniel (US Fish and Wildlife Service, Kalispell, MT); Cavigli, Jon (Montana Department of Fish, Wildlife and Parks, Kalispell, MT)

    1996-06-01

    The operation of Hungry Horse Dam on the South Fork-of the Flathead River reduced the reproductive success of kokanee (Oncorhynchus nerka) spawning in the Flathead River. Montana Fish, Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribes (CSKT) authored a mitigation plan to offset those losses. The mitigation goal, stated in the Fisheries Mitigation Plan for Losses Attributed to the Construction and Operation of Hungry Horse Dam, is to: {open_quotes}Replace lost annual production of 100,000 kokanee adults, initially through hatchery production and pen rearing in Flathead Lake, partially replacing lost forage for lake trout (Salvelinus namaycush) in Flathead Lake.{close_quotes}

  12. A new morphospecies of Microcystis sp. forming bloom in the Cheffia dam (Algeria): seasonal variation of microcystin concentrations in raw water and their removal in a full-scale treatment plant.

    Science.gov (United States)

    Nasri, Hichèm; Bouaïcha, Noureddine; Harche, Merieme Kaid

    2007-08-01

    Toxic cyanobacterial blooms are an increasing problem in Algeria. The production of cyanotoxins (microcystins) and their presence in drinking water represent growing hazards to human health. In this study, seasonal variations in the concentrations of total microcystins and physicochemical parameters (pH, temperature, dissolved oxygen, nitrate, orthophosphate, and chlorophyll-a) were analyzed in the Cheffia dam (Algeria), mainly used to supply drinking water. The removal of cyanobacterial cells and microcystins was also evaluated in full-scale plant associated with the Cheffia reservoir. The levels of microcystins (MCYSTs) in both raw and drinking water were evaluated using the protein phosphatase type 2A (PP2A) inhibition test as MCYST-LR equivalents. Identification of microcystin variants was achieved by LC/MS/MS. During the period of study (March-December 2004), microscopic observation showed the dominance in the autumn months (September-November) of a new morphospecies of Microcystis sp. The MCYST-LR equivalent concentrations in raw water varied between 50.8 and 28,886 ng L(-1). The highest level of toxins was observed in October 2004 and was significantly correlated with the chlorophyll-a. Three variants of microcystins assigned as microcystin-YR (MCYST-YR), microcystin-LR (MCYST-LR), and 6Z-Adda stereoisomer of MCYST-LR were observed in the crude extract of the Microcystis sp. bloom sample. During the bloom period, total elimination of Microcystis sp. and toxins were achieved through a classical treatment plant comprised of coagulation and flocculation, powdered activated carbon at 15 mg L(-1), slow sand filtration and chlorination before storage.

  13. Living with dams

    NARCIS (Netherlands)

    H.L.F. Saeijs (Henk); K.D. Schuijt (Kirsten)

    2002-01-01

    textabstractDams have proven their usefulness in preventing and mitigating floods, and water scarcity and generating electricity. They are indispensable in present society. But at the same time, they cause serious ecological, social and economical problems. Consequently we have to live with a dams

  14. Channel evolution on the dammed Elwha River, Washington, USA

    Science.gov (United States)

    Draut, A.E.; Logan, J.B.; Mastin, M.C.

    2011-01-01

    Like many rivers in the western U.S., the Elwha River, Washington, has changed substantially over the past century in response to natural and human forcing. The lower river is affected by two upstream dams that are slated for removal as part of a major river restoration effort. In preparation for studying the effects of dam removal, we present a comprehensive field and aerial photographic analysis of dam influence on an anabranching, gravel-bed river. Over the past century with the dams in place, loss of the upstream sediment supply has caused spatial variations in the sedimentary and geomorphic character of the lower Elwha River channel. Bed sediment is armored and better sorted than on the naturally evolving bed upstream of the dams. On time scales of flood seasons, the channel immediately below the lower dam is fairly stable, but progresses toward greater mobility downstream such that the lowermost portion of the river responded to a recent 40-year flood with bank erosion and bed-elevation changes on a scale approaching that of the natural channel above the dams. In general, channel mobility in the lowest 4 km of the Elwha River has not decreased substantially with time. Enough fine sediment remains in the floodplain that – given sufficient flood forcing – the channel position, sinuosity, and braiding index change substantially. The processes by which this river accesses new fine sediment below the dams (rapid migration into noncohesive banks and avulsion of new channels) allow it to compensate for loss of upstream sediment supply more readily than would a dammed river with cohesive banks or a more limited supply of alluvium. The planned dam removal will provide a valuable opportunity to evaluate channel response to the future restoration of natural upstream sediment supply.

  15. 78 FR 44187 - Montana Disaster # MT-00079

    Science.gov (United States)

    2013-07-23

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Montana Disaster MT-00079 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY... have been determined to be adversely affected by the disaster: Primary Counties: Blaine,...

  16. Notes and comments on Montana Refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a summary of actual management actions, and plant community responses on Montana refuges during 1992. It is part of the moist-soil expert system...

  17. Adminstrative Boundary for Glacier National Park, Montana

    Data.gov (United States)

    National Park Service, Department of the Interior — The current administrative boundary of Glacier National Park, Montana. This data is based on 1:24000 scale USGS quad mapping published in 1968, but was revised in...

  18. Waterfowl breeding population survey for Montana: 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Breeding Population and Habitat Survey for Montana during 1993. The primary purpose of the survey is to provide information on...

  19. Parcels and Land Ownership - Montana Cadastral Framework

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Montana Cadastral Database is comprised of taxable parcels (fee land) and public land (exempt property). It is not broken down into individual lots, for instance...

  20. Waterfowl breeding population survey for Montana: 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Breeding Population and Habitat Survey for Montana during 1998. The primary purpose of the survey is to provide information on...

  1. Waterfowl production survey for Montana: July 1980

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Production and Habitat Survey for Montana during 1980. The primary purpose of the survey is to provide information on duck...

  2. Watershed Boundaries - Watershed Boundary Database for Montana

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This data set is a complete digital hydrologic unit boundary layer of the Subbasins (8-digit), Watersheds (10-digit), and Subwatersheds (12-digit) for Montana. This...

  3. Statistical summaries of streamflow in Montana and adjacent areas, water years 1900 through 2002

    Science.gov (United States)

    McCarthy, Peter M.

    2005-01-01

    In response to the need to have more current information about streamflow characteristics in Montana, the U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality, Confederated Salish and Kootenai Tribes, and Bureau of Land Management, conducted a study to analyze streamflow data. Updated statistical summaries of streamflow characteristics are presented for 286 streamflow-gaging sites in Montana and adjacent areas having 10 or more years of record for water years 1900 through 2002. Data include the magnitude and probability of annual low and high flow, the magnitude and probability of low flow for three seasons (March-June, July-October, and November-February), flow duration of the daily mean discharge, and the monthly and annual mean discharges. For streamflow-gaging stations where 20 percent or more of the contributing drainage basin is affected by dams or other large-scale human modification, streamflow is considered regulated. Separate streamflow characteristics are presented for the unregulated and regulated periods of record for sites with sufficient data.

  4. Measured and Estimated Sodium-Adsorption Ratios for Tongue River and its Tributaries, Montana and Wyoming, 2004-06

    Science.gov (United States)

    Cannon, M.R.; Nimick, David A.; Cleasby, Thomas E.; Kinsey, Stacy M.; Lambing, John H.

    2007-01-01

    Decker, Montana, station 06306300, (3) Tongue River Dam near Decker, Montana, station 06307500, (4) Birney Day School Bridge near Birney, Montana, station 06307616, (5) below Brandenberg Bridge near Ashland, Montana, station 06307830, (6) above T&Y Diversion Dam near Miles City, Montana, station 06307990, and (7) Miles City, Montana, station 06308500. Water samples were collected and analyzed from five sites on tributaries located at: (1) Goose Creek near Acme, Wyoming, station 06305700, (2) Prairie Dog Creek near Acme, Wyoming, station 06306250, (3) Hanging Woman Creek near Birney, Montana, station 06307600, (4) Otter Creek at Ashland, Montana, station 06307740, and (5) Pumpkin Creek near Miles City, Montana, station 06308400. All water-quality data for samples collected at these 12 sites can be accessed at Web sites http://waterdata.usgs.gov/mt/nwis or http://waterdata.usgs.gov/wy/nwis.

  5. Allegheny County Dam Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the point locations of dams in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  6. Dams: Pros and Cons

    African Journals Online (AJOL)

    Steve

    The Dam was built for the main purpose of water supply to university community. Data on .... The decision on who is to participate in a full EIA on a water ... METHOD AND MATERIALS ..... Development”, Encyclopedia of Life Support Systems,.

  7. Water-quality trends and constituent-transport analysis for selected sampling sites in the Milltown Reservoir/Clark Fork River Superfund Site in the upper Clark Fork Basin, Montana, water years 1996–2015

    Science.gov (United States)

    Sando, Steven K.; Vecchia, Aldo V.

    2016-07-20

    During the extended history of mining in the upper Clark Fork Basin in Montana, large amounts of waste materials enriched with metallic contaminants (cadmium, copper, lead, and zinc) and the metalloid trace element arsenic were generated from mining operations near Butte and milling and smelting operations near Anaconda. Extensive deposition of mining wastes in the Silver Bow Creek and Clark Fork channels and flood plains had substantial effects on water quality. Federal Superfund remediation activities in the upper Clark Fork Basin began in 1983 and have included substantial remediation near Butte and removal of the former Milltown Dam near Missoula. To aid in evaluating the effects of remediation activities on water quality, the U.S. Geological Survey began collecting streamflow and water-quality data in the upper Clark Fork Basin in the 1980s.Trend analysis was done on specific conductance, selected trace elements (arsenic, copper, and zinc), and suspended sediment for seven sampling sites in the Milltown Reservoir/Clark Fork River Superfund Site for water years 1996–2015. The most upstream site included in trend analysis is Silver Bow Creek at Warm Springs, Montana (sampling site 8), and the most downstream site is Clark Fork above Missoula, Montana (sampling site 22), which is just downstream from the former Milltown Dam. Water year is the 12-month period from October 1 through September 30 and is designated by the year in which it ends. Trend analysis was done by using a joint time-series model for concentration and streamflow. To provide temporal resolution of changes in water quality, trend analysis was conducted for four sequential 5-year periods: period 1 (water years 1996–2000), period 2 (water years 2001–5), period 3 (water years 2006–10), and period 4 (water years 2011–15). Because of the substantial effect of the intentional breach of Milltown Dam on March 28, 2008, period 3 was subdivided into period 3A (October 1, 2005–March 27, 2008

  8. 76 FR 43259 - Southern Montana Resource Advisory Committee

    Science.gov (United States)

    2011-07-20

    ... in Billings, Montana. The committee is meeting as authorized under the Secure Rural Schools and... Grad Montana Hotel and Convention Center, 5500 Midland Road, Billings, MT. Written comments should...

  9. Science Inquiry Learning in Classrooms — Montana Style

    Science.gov (United States)

    Brelsford, M. A.; Peters, J.; Grimberg, B. I.

    2010-04-01

    Montana's ABRC is working with rural school teachers in southwestern Montana. Astrobiology is a new and exciting subject for the teachers and its inter-disciplinary nature is very useful and rewarding for the teachers and their students.

  10. Observations on a Montana water quality proposal.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Puder, M. G.

    2006-01-12

    In May 2005, a group of petitioners led by the Northern Plains Resource Council (NPRC) submitted a petition to revise water quality requirements to the Montana Board of Environmental Review (BER). Under Montana law, the BER had to consider the petition and either reject it or propose it as a new regulation. In September 2005, the BER announced proposed changes to the Montana water quality regulations. The proposal, which included almost the exact language found in the petition, was directed toward discharges of water from coal bed natural gas (CBNG) production. The key elements of the proposal included: (1) No discharges of CBNG water are allowed to Montana surface waters unless operators can demonstrate that injection to aquifers with the potential for later recovery of the water is not feasible. (2) When operators can demonstrate the injection is not feasible, the CBNG water to be discharged must meet very strict technology-based limits for multiple parameters. (3) The Montana water quality standards for the sodium adsorption ratio (SAR) and electrical conductivity (EC) would be evaluated using the 7Q10 flow (lowest 7-consecutive-day flow in a 10-year period) rather than a monthly flow that is currently used. (4) SAR and EC would be reclassified as ''harmful parameters'', thereby greatly restricting the ability for CBNG discharges to be allowed under Montana's nondegradation regulations. The proposed regulations, if adopted in their current form, are likely to substantially reduce the amount of CBNG production in Montana. The impact also extends to Wyoming CBNG production through much greater restrictions on water quality that must be met at the interstate border.

  11. Examining the economic impacts of hydropower dams on property values using GIS.

    Science.gov (United States)

    Bohlen, Curtis; Lewis, Lynne Y

    2009-07-01

    While the era of dam building is largely over in the United States, globally dams are still being proposed and constructed. The articles in this special issue consider many aspects and impacts of dams around the world. This paper examines dam removal and the measurement of the impacts of dams on local community property values. Valuable lessons may be found. In the United States, hundreds of small hydropower dams will come up for relicensing in the coming decade. Whether or not the licenses are renewed and what happens to the dams if the licenses expires is a subject of great debate. Dams are beginning to be removed for river restoration and fisheries restoration and these "end-of-life" decisions may offer lessons for countries proposing or currently building small (and large) hydropower dams. What can these restoration stories tell us? In this paper, we examine the effects of dams along the Penobscot River in Maine (USA) on residential property values. We compare the results to findings from a similar (but ex post dam removal) data set for properties along the Kennebec river in Maine, where the Edwards Dam was removed in 1999. The Penobscot River Restoration Project, an ambitious basin-wide restoration effort, includes plans to remove two dams and decommission a third along the Penobscot River. Dam removal has significant effects on the local environment, and it is reasonable to anticipate that environmental changes will themselves be reflected in changes in property values. Here we examine historical real estate transaction data to examine whether landowners pay a premium or penalty to live near the Penobscot River or near a hydropower generating dam. We find that waterfront landowners on the Penobscot or other water bodies in our study area pay approximately a 16% premium for the privilege of living on the water. Nevertheless, landowners pay LESS to live near the Penobscot River than they do to live further away, contrary to the expectation that bodies of water

  12. Board of Regents' Montana University System (MUS) Strategic Plan 2016

    Science.gov (United States)

    Montana University System, 2016

    2016-01-01

    The Montana University System Strategic Plan is the primary planning document of the Board of Regents. The Plan sets forth an agenda for higher education in Montana by delineating the strategic directions, goals, and objectives that guide the Montana University System (MUS). In July 2006, after several years of study, public dialogue, and internal…

  13. Quasi-stable Slope-Failure Dams in High Asia

    Science.gov (United States)

    Shroder, J. F.

    2010-12-01

    Collapses of steep mountain slopes in the Himalaya, Karakoram, Pamir, Hindu Kush, and Tibetan Plateau are well known as a result of:(1) generally high seismicity in active tectonic areas; (2) prior deglaciation leaving undercut, unstable cliffs; (3) present-day debuttressing of rock cliffs by glacial down-wasting in conditions of global warming; and (4) degradation of permafrost cohesion and water-ice cementation in high mountain slopes. Landslide dams across mountain rivers are also well known worldwide and generally do not endure for long because of the common landslide-lake outburst floods (LLOF) whose discharge is commonly sufficiently large to remove much of the dam in a short time. A number of massive slope-failure dams in south High Asia, however, have endured for centuries and require explanations for the length of duration, whereas recent examples require robust assessment for better predictive hazard analysis. Three main factors contribute to longevity of slope-failure dams: (1) mega-rocks >15-30 m that inhibit dam failure in overflow breaches; (2) mega-porosity wherein incoming discharge to the landslide lake is balanced by subterranean water through-flow within the landslide dam; (3) impermeable clay fills caused by remobilization of prior lacustrine-dammed sediment that impart dam strength to allow lasting integrity for a time, and (4) climate-change induced lake-level lowering. Several examples of long-lived or unusually stable, slope-failure dams associated with pronounced structural/tectonic associations include: (1) Pangong Tso, Ladakh and Tibet; (2) Lake Shewa, Afghanistan; (3) Sarez Lake, Tajikistan; and (4) Lake Hunza, Pakistan. Pangong Tso and Lake Shewa were emplaced thousands of years ago and only Lake Shewa shows some instability of the dam front where percolating water maintains lake level but may be causing new slumping. Sarez Lake behind the Usoi landslide dam was emplaced by an earthquake in 1911 and maintains its level by seepage. Lake

  14. Investigation on the Causes of Cracking in Earth Dams (Case study: Mahmood-Abad Earth Dam

    Directory of Open Access Journals (Sweden)

    H. Rahimi

    2016-09-01

    river base beneath the dam structure. In fact , this layer has not been considered in the analysis as well in design. Because of fully saturated condition of this layer in an operation period of dam it might subjected to liquefaction during the happening of the earthquake. Evaluation of liquefaction potential of this layer based on Seed and Idriss (1971 diagram showed probability of this phenomenon. To prove this hypothesis, the stability analysis had been conducted in two different conditions by including the thin sandy layer and without considering the mentioned layer. The analysis showed in the case of absence of sandy layer the required safety factor was satisfied, but including the sandy layer leads cause the safety factor dropped to 0.84 that means accruing of liquefaction in the thin layer would lead to structural instability of the studied dam. The simulation of the behavior of dam by employing the accrued earthquake acceleration confirmed the liquefaction has been accrued in the thin sandy layer. The results of finite element simulation showed the depth of the cracks on the crest is about 2 meters and also the upstream slope has slipped about 81 mm to the reservoir of the dam. These results was consistent with the observed values. To overcome the next risks, also to repair the damaged parts of the dam, 3 different methods had been proposed. The curing technics was deploying of the reservoir and removing of the damage part of the dam and as well the thin sandy layer and reconstructed that part of dam, Deploying of reservoir of the dam and adjusting the slope of the upper shoulder to stable condition and at least repairing the developed cracks by injecting cement slurry and tolerate the current condition without imposition any additional costs to the project. The third method has been selected, but for any probable risky condition monitoring of the dam has been advised. Conclusion: Based on the overall results of the investigations, it was concluded that cracking

  15. Collapse Modeling of a Masonry Arch Dam Using the Cohesive Interface Elements

    Directory of Open Access Journals (Sweden)

    Jianwen Pan

    2015-01-01

    Full Text Available A finite element (FE approach with zero-thickness cohesive interface elements is presented to simulate collapse of continuum structures. The element removal technique merged with the general contact algorithm is adapted in the FE approach to achieve modeling for a transition from continua to discontinua, that is, fracture, fragmentation, and collapse. Collapse process of Meihua masonry arch dam, which is a famous disaster in dam engineering in China, is simulated and the failure mechanism is studied. The collapse process obtained from the presented procedure coincides with the field observation after the dam failure. The failure of Meihua arch dam can be attributed to reducing shear strength of the peripheral joint between the dam body and the concrete pedestal by daubing a layer of asphalt there. With low sliding resistance strength, the masonry dam body may slide upwards along the peripheral joint under hydrostatic pressure, leading to weakening of the arch action, fracturing, and final collapse of the dam.

  16. Seepage Control Design of Dam Diaphragm Wall Combined with Grout Curtain for Danger-removing and Consolidating Project of Taiping Reservoir%太平水库除险加固工程墙幕结合防渗设计

    Institute of Scientific and Technical Information of China (English)

    王彩丽

    2012-01-01

    太平水库于1975年建成,已运行30多年,枢纽建筑物存在诸多问题,其中问题之一就是坝肩及坝基渗漏问题,已影响到水库经济效益及运行安全,为此采取了防渗墙与帷幕灌浆相结合的防渗处理措施以解决这一问题。文中介绍了水库的防渗设计,帷幕灌浆和防渗墙的施工工艺及质量控制。%The Taiping Reservoir had been completed in the year 1975,and its operation has lasted for 30-odd years.But there are many problems in building of hydroproject,one of which is seepage in dam shoulder and dam foundation.This problem has impacted the reservoir's economical benefit and operation safety.Therefore,a seepage control measure of dam diaphragm wall combined with grout curtain is adopted to solve this problem.In this paper,the reservoir's seepage control design,the construction techniques and the quality control measures of grout curtain and diaphrage wall are expounded.

  17. Final report on the safety assessment of Arnica montana extract and Arnica montana.

    Science.gov (United States)

    2001-01-01

    Arnica Montana Extract is an extract of dried flowerheads of the plant, Arnica montana. Arnica Montana is a generic term used to describe a plant material derived from the dried flowers, roots, or rhizomes of A. montana. Common names for A. montana include leopard's bane, mountain tobacco, mountain snuff, and wolf's bane. Two techniques for preparing Arnica Montana Extract are hydroalcoholic maceration and gentle disintegration in soybean oil. Propylene glycol and butylene glycol extractions were also reported. The composition of these extracts can include fatty acids, especially palmitic, linoleic, myristic, and linolenic acids, essential oil, triterpenic alcohols, sesquiterpene lactones, sugars, phytosterols, phenol acids, tannins, choline, inulin, phulin, arnicin, flavonoids, carotenoids, coumarins, and heavy metals. The components present in these extracts are dependent on where the plant is grown. Arnica Montana Extract was reported to be used in almost 100 cosmetic formulations across a wide range of product types, whereas Arnica Montana was reported only once. Extractions of Arnica Montana were tested and found not toxic in acute toxicity tests in rabbits, mice, and rats; they were not irritating, sensitizing, or phototoxic to mouse or guinea pig skin; and they did not produce significant ocular irritation. In an Ames test, an extract of A. montana was mutagenic, possibly related to the flavenoid content of the extract. No carcinogenicity or reproductive/developmental toxicity data were available. Clinical tests of extractions failed to elicit irritation or sensitization, yet Arnica dermatitis, a delayed type IV allergy, is reported in individuals who handle arnica flowers and may be caused by sesquiterpene lactones found in the flowers. Ingestion of A. montana-containing products has induced severe gastroenteritis, nervousness, accelerated heart rate, muscular weakness, and death. Absent any basis for concluding that data on one member of a botanical

  18. Montana BioDiesel Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Peyton, Brent [Montana State Univ., Bozeman, MT (United States)

    2017-01-29

    This initiative funding helped put Montana State University (MSU) in a position to help lead in the development of biodiesel production strategies. Recent shortages in electrical power and rising gasoline prices have focused much attention on the development of alternative energy sources that will end our dependence on fossil fuels. In addition, as the concern for environmental impact of utilizing fossil fuels increases, effective strategies must be implemented to reduce emissions or the increased regulations imposed on fossil fuel production will cause economic barriers for their use to continue to increase. Biodiesel has been repeatedly promoted as a more environmentally sound and renewable source of fuel and may prove to be a highly viable solution to provide, at the least, a proportion of our energy needs. Currently there are both practical and economic barriers to the implementation of alternative energy however the advent of these technologies is inevitable. Since many of the same strategies for the storage, transport, and utilization of biodiesel are common with that of fossil fuels, the practical barriers for biodiesel are comparatively minimal. Strategies were developed to harness the CO2 as feedstock to support the growth of biodiesel producing algae. The initiative funding led to the successful funding of highly rated projects in competitive national grant programs in the National Science Foundation and the Department of Energy. This funding put MSU in a key position to develop technologies to utilize the CO2 rich emissions produced in fossil fuel utilization and assembled world experts concerning the growth characteristics of photosynthetic microorganisms capable of producing biodiesel.

  19. Dam safety in British Columbia

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, H.M.; Round, R.P.D.

    1978-01-01

    Many dams in British Columbia were built before 1900, and a comprehensive inspection and surveillance program has been developed. The background and implementation of this program are described. Topics discussed include program responsibilities, classification of dams, organization, the dam safety program, and coordination with other agencies. (PMA)

  20. A stream of consciousness: the anti-dam movement' impact on rivers in the 20th century

    Energy Technology Data Exchange (ETDEWEB)

    McCully, P.

    2000-07-01

    It is argued that the 20th century devastated the world's rivers like no other period in history. In the past one hundred years some 40,000 large dams were built on the world's rivers; there are few rivers of any consequence left that remain dam-free. Dam reservoirs have flooded perhaps a million square kilometres of land and displaced up to 60 million people. The environmental toll has been equally shocking: estuaries were degraded, fisheries decimated, forest destroyed. This report describes a strong and growing people's counter-movement to save rivers and riverine communities. These actions by people and the poor economics of dam building, are making it increasingly difficult to build dams in most of the world. Construction of large dams is declining fast, from a peak of about 540 in the 1970s to 200 in the 1990s. In addition to the decline in the construction of new dams, the people's movement has been successful in forcing the decommissioning and removal of several major dams in recent years. Examples of the movement's success in bringing about the removal of some existing dams or halt the construction of new ones are cited from Hungary, India, and particularly the United States where nearly 500 dams were removed during the past 100 years. Specific examples of dam removal efforts are described, taken from Pennsylvania, Wisconsin, and from the Colombia/Snake River basin. The most exciting decommissioning effort involves taking on the dams that submerged Hetch Hetchy Valley in the Yosemite National Park and the Glen Canyon Dam on the Colorado River. A chronological table of the 'Boom Years of Dam Building' and 'The Rise of the People's Movement Against Dams' is attached.

  1. 76 FR 76111 - Montana Regulatory Program

    Science.gov (United States)

    2011-12-06

    ...--Regulatory Planning and Review This rule is exempted from review by the Office of Management and Budget (OMB... to and additions of statutory definitions for ``approximate original contour,'' ``in situ coal..., Federal Register (45 FR 21560). You can also find later actions concerning Montana's program and...

  2. 77 FR 73965 - Montana Regulatory Program

    Science.gov (United States)

    2012-12-12

    ... Section 503(a) of the Act permits a State to assume primacy for the regulation of surface coal mining and... Office of Surface Mining Reclamation and Enforcement 30 CFR Part 926 Montana Regulatory Program AGENCY: Office of Surface Mining Reclamation and Enforcement, Interior. ACTION: Proposed rule; withdrawal...

  3. Montana Advanced Biofuels Great Falls Approval

    Science.gov (United States)

    This November 20, 2015 letter from EPA approves the petition from Montana Advanced Biofuels, LLC, Great Falls facility, regarding ethanol produced through a dry mill process, qualifying under the Clean Air Act for advanced biofuel (D-code 5) and renewable

  4. 76 FR 64047 - Montana Regulatory Program

    Science.gov (United States)

    2011-10-17

    ... until 4 p.m., m.d.t. November 16, 2011. If requested, we will hold a public hearing on the amendment on November 14, 2011. We will accept requests to speak until 4 p.m., m.d.t. on November 1, 2011. ADDRESSES... . Edward L. Coleman, Bureau Chief, Industrial and Energy Minerals Bureau, Montana Department...

  5. 76 FR 64045 - Montana Regulatory Program

    Science.gov (United States)

    2011-10-17

    ... hearing, if one is requested. DATES: We will accept written comments on this amendment until 4 p.m., m.d.t... will accept requests to speak until 4 p.m., m.d.t. on November 1, 2011. ADDRESSES: You may submit... ; Edward L. Coleman, Bureau Chief, Industrial and Energy Minerals Bureau, Montana Department...

  6. A comparison of different rubber dam systems on a dental simulator.

    Science.gov (United States)

    Kapitan, Martin; Sustova, Zdenka; Ivancakova, Romana; Suchanek, Jakub

    2014-01-01

    The purpose of this study was to test the hypothesis that more recently developed rubber dam systems (OptraDam ® Plus and OptiDam™) are faster and easier to handle, and that the quality of isolation is not decreased. The rubber dam systems were applied in standard conditions on a dental simulator in several model clinical situations. The time of preparation, application and removal were measured and the quality of isolation was evaluated. The median time of rubber dam placement was 51 s (Q1 = 38 s; Q3 = 79 s). The shortest median time of application was with OptiDam™ (42 s), followed by a conventional rubber dam (53 s), and finally the longest was with OptraDam® Plus (58 s). The median volume of fluid remaining in the isolated space after 5 minutes was 9.5 mL (Q1 = 8 mL; Q3 = 10 mL). The largest median volume of remaining water was with OptiDam™ (10 mL), followed by a conventional rubber dam (9.5 mL) and the least with OptraDam® Plus (8.5 mL). The afore-stated hypothesis about the advantages of modern rubber dam isolation systems was accepted for OptiDam™, but rejected for OptraDam® Plus. The results could contribute to decision-making concerning the choice of rubber dam system.

  7. Predação e remoção de sementes de cinco espécies de palmeiras por Guerlinguetus ingrami (Thomas, 1901 em um fragmento urbano de Floresta Atlântica Montana Predation and removal of seeds from five species of palms by Guerlinguetus ingrami (Thomas, 1901 in an urban fragment of the Montane Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Luci Ferreira Ribeiro

    2010-08-01

    Full Text Available Em um fragmento urbano de Floresta Ombrófila Densa Montana no Estado do Espírito Santo (Sudeste do Brasil, foram avaliados o padrão de frugivoria e as proporções de remoção, predação e armazenamento de frutos por Guerlinguetus ingrami, em relação a cinco espécies de palmeira (Syagrus pseudococos, S. ruschiana, Bactris setosa, Polyandrococos caudescens e Euterpe edulis. As espécies de Arecaceae enquadram-se na síndrome associada à dispersão por G. ingrami, na qual as espécies de plantas apresentam alta produção, grandes frutos com poucas sementes envolvidas por endocarpos resistentes e que não são usadas por outros predadores de sementes arborícolas. Os resultados apontaram que existem diferenças no padrão de frugivoria da espécie G. ingrami quando comparadas com as de espécies com a mesma síndrome; aquelas que possuem frutos maiores apresentaram maior taxa de remoção e de armazenamento de seus diásporos. E, devido à especificidade exibida por G. ingrami na atividade de dispersão de sementes, este roedor deverá atuar apenas em trocas compensatórias específicas em pequenos fragmentos defaunados. Portanto, a seletividade de G. ingrami poderia indicar que o seu papel como dispersor em pequenos fragmentos estaria restrito em função da maior probabilidade de mortalidade associada às plantas preferencialmente dispersas por essa espécie, e sua atuação como predador de sementes deve ser quantificada para que os seus efeitos, em pequenos fragmentos, sejam mais bem compreendidos.This study investigated the fruvigory pattern of Guerlinguetus ingrami, considering the removal, predation and caching of the fruits of palm species (Syagrus pseudococos, S. ruschiana, Bactris setosa, Polyandrococos caudescens and Euterpe edulis in an urban forest fragment of the montane Atlantic forest in the state of Espírito Santo, Southeastern Brazil. These palm species show characteristics theoretically expected to be seen in plants

  8. Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for Montana

    Energy Technology Data Exchange (ETDEWEB)

    Mendon, Vrushali V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, Mingjie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Taylor, Zachary T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poehlman, Eric A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-02-15

    The 2015 IECC provides cost-effective savings for residential buildings in Montana. Moving to the 2015 IECC from the 2014 Montana State Code base code is cost-effective for residential buildings in all climate zones in Montana.

  9. Dam design can impede adaptive management of environmental flows: a case study from the Opuha Dam, New Zealand.

    Science.gov (United States)

    Lessard, JoAnna; Hicks, D Murray; Snelder, Ton H; Arscott, David B; Larned, Scott T; Booker, Doug; Suren, Alastair M

    2013-02-01

    The Opuha Dam was designed for water storage, hydropower, and to augment summer low flows. Following its commissioning in 1999, algal blooms (dominated first by Phormidium and later Didymosphenia geminata) downstream of the dam were attributed to the reduced frequency and magnitude of high-flow events. In this study, we used a 20-year monitoring dataset to quantify changes associated with the dam. We also studied the effectiveness of flushing flows to remove periphyton from the river bed. Following the completion of the dam, daily maximum flows downstream have exceeded 100 m(3) s(-1) only three times; two of these floods exceeded the pre-dam mean annual flood of 203 m(3) s(-1) (compared to 19 times >100 m(3) s(-1) and 6 times >203 m(3) s(-1) in the 8 years of record before the dam). Other changes downstream included increases in water temperature, bed armoring, frequency of algal blooms, and changes to the aquatic invertebrate community. Seven experimental flushing flows resulted in limited periphyton reductions. Flood wave attenuation, bed armoring, and a shortage of surface sand and gravel, likely limited the effectiveness of these moderate floods. Floods similar to pre-dam levels may be effective for control of periphyton downstream; however, flushing flows of that magnitude are not possible with the existing dam infrastructure. These results highlight the need for dams to be planned and built with the capacity to provide the natural range of flows for adaptive management, particularly high flows.

  10. Radiation Protection Optimization for Removal and Installation of Nozzle Dams at Ningde Nuclear Powe r Plant%宁德核电厂蒸汽发生器装拆堵板的辐射防护最优化管理

    Institute of Scientific and Technical Information of China (English)

    邓克春; 郭飞; 杨岩; 杨小强

    2014-01-01

    蒸汽发生器一次侧水室装拆堵板是压水堆核电站大修的一项重要工作,具有较大的辐射风险。本文主要介绍了宁德核电站在安装和拆卸堵板工作中,实施辐射防护最优化的方法及效果。%The removal and installation of nozzle dams (RIND ) at primary water chamber of steam generator (SG ) is one of the essential maintenance jobs ,with high radiation risk during outage at a PWR nuclear power plant .This paper introduces the method and effect of implementing ALARA principle for RIND by radiation protection (RP) staff at Ningde nuclear power plant .

  11. Government Districts, Other - Montana Administrative Boundary Web Mapping Service

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Montana Administrative Boundaries Map Service includes the following boundaries: State, County, Incorporated City/Town, Reservation, School Districts, Tax Increment...

  12. Analysing and Selecting the Schemes of Removing Danger and Consolidating Dam for Bosigan Reservoir in Pishan County of XinJiang Uygur Autonomous Region%新疆皮山县波斯干水库除险加固坝体方案的分析与确定

    Institute of Scientific and Technical Information of China (English)

    王勇

    2012-01-01

    The Bosigan Reservoir is located in Pishan County of Hetian Prefecture in XinJiang Uygur Autonomous Region.This reservoir was constructed in the 1970's.Its total reservoir capacity is 3×106 m3,the initial design beneficial capacity is 1.5×106 m3.But the present silted capacity has reached 1.288×106 m3,and the remainder capacity only 0.2117×106 m3.So this reservoir needs very much removing danger and consolidating.In the paper,the selection of capacity-restoring mode between dam-heightening scheme and reservoir sediment removal scheme,and the selection of seepage control mode between vertical seepage control scheme and upstream dam slope seepage control scheme are expounded in many aspects.At last,the reasonable schemes are selected,and the reservoir's normal functions on flood control and irrigation can be restored,and reach satisfying use effect.%波斯干水库位于新疆和田地区皮山县境内,工程建于上世纪70年代,总库容300万m3,兴利库容150万m3,现已淤积128.83万m3,剩余库容21.17万m3,迫切需要进行除险加固。文中从是对坝体加高还是对水库清淤、对坝体是进行垂直防渗还是对边坡防渗等经过多方面比选,最终确定合理的除险加固方式,恢复其正常的防洪和灌溉功能,以达到满意的工程使用效果。

  13. Riparian soil development linked to forest succession above and below dams along the Elwha River, Washington, USA

    Science.gov (United States)

    Perry, Laura G; Shafroth, Patrick B.; Perakis, Steven

    2017-01-01

    Riparian forest soils can be highly dynamic, due to frequent fluvial disturbance, erosion, and sediment deposition, but effects of dams on riparian soils are poorly understood. We examined soils along toposequences within three river segments located upstream, between, and downstream of two dams on the Elwha River to evaluate relationships between riparian soil development and forest age, succession, and channel proximity, explore dam effects on riparian soils, and provide a baseline for the largest dam removal in history. We found that older, later-successional forests and geomorphic surfaces contained soils with finer texture and greater depth to cobble, supporting greater forest floor mass, mineral soil nutrient levels, and cation exchange. Forest stand age was a better predictor than channel proximity for many soil characteristics, though elevation and distance from the channel were often also important, highlighting how complex interactions between fluvial disturbance, sediment deposition, and biotic retention regulate soil development in this ecosystem. Soils between the dams, and to a lesser extent below the lower dam, had finer textures and higher mineral soil carbon, nitrogen, and cation exchange than above the dams. These results suggested that decreased fluvial disturbance below the dams, due to reduced sediment supply and channel stabilization, accelerated soil development. In addition, reduced sediment supply below the dams may have decreased soil phosphorus. Soil δ15N suggested that salmon exclusion by the dams had no discernable effect on nitrogen inputs to upstream soils. Recent dam removal may alter riparian soils further, with ongoing implications for riparian ecosystems.

  14. WEST PIONEER WILDERNESS STUDY AREA, MONTANA.

    Science.gov (United States)

    Berger, Byron R.; Benham, John R.

    1984-01-01

    The West Pioneer Wilderness Study Area is in the Pioneer Mountains, Beaverhead County, Montana. A mineral-resource study of the area identified eight areas with molybdenum potential, four areas with gold-silver potential, one area with tungsten potential, and one area with barite potential. Several small mines were encountered, but none were accessible for the purposes of resource evaluation. No energy resources were identified in the study.

  15. Synthesizing Fluvial Sedimentary and Geomorphic Response to Dam Removal—A Two-Decade Perspective

    Science.gov (United States)

    East, A. E.; Major, J. J.; Bountry, J.; Randle, T. J.; O'Connor, J. E.; Grant, G.; Wilcox, A. C.; Magirl, C. S.; Magilligan, F. J.; Collins, M. J.; Pess, G. R.; Tullos, D. D.

    2015-12-01

    Over the last several decades there has been a marked increase in the number of dams removed in the United States, including the recent removal of large dams impounding millions of cubic meters of sediment. From these removals, common findings have begun to emerge: (1) Rivers are resilient, showing rapid geomorphic and sedimentary response to dam removals, especially when removals are sudden rather than prolonged, and where rivers have adequate stream power. Rivers can rapidly evacuate large percentages of stored reservoir sediment (≥40% within one year)—particularly where sediment is coarse-grained (sand and gravel), and can move evacuated sediment long distances (>20 km downstream) within a year, given sufficient transport capacity. The channel downstream typically takes months to years—not decades—to achieve a degree of stability within its natural range of variability. (2) Modest flows can erode large amounts of reservoir sediment and move it downstream. Large floods are not required to move substantial sediment volumes, especially from non-cohesive reservoir deltas. Once the most easily accessed sediment is eroded, however, larger floods can continue to access the remnant reservoir sediment and redistribute it downstream. Portions of the redistributed sediment remain (up- and downstream of the dam site), shaping a new landscape. (3) Dam height, sediment volume, and sediment grain size and cohesion strongly influence response to dam removal. Although removals of small dams with little stored sediment are more common, removals of large dams (≥10 m) with major sediment releases have had longer-lasting and more widespread downstream effects. (4) Downstream valley morphology and hydrology strongly influence the distribution of released sediment. Bedrock confinement versus wide alluvial reaches, downstream channel gradient, locations and depths of channel pools, locations and geometries of existing channel bars, position of the dam within a watershed, and

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

    Science.gov (United States)

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

    2013-01-01

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

  17. The dam design of Three Gorges Project

    Institute of Scientific and Technical Information of China (English)

    Wang Xiaomao; Xu Linxiang; Liao Renqiang

    2011-01-01

    The dam of Three Gorges Project is a concrete gravity dam with the crest elevation of 185 m, the maximum height of 181 m and dam axis length of 2 309.5 m. The dam consists of spillway, powerhouse, non-over flow, ship-lift, temporary ship-lock, left diversion wall and longitudinal cofferdam blocks. Some key techniques relating to dam structure design are presented, including hydraulics of flood discharge structure, dam joint design, layout and structural type of penstock, deep anti-sliding stability of dam foundation, reconstruction of temporary ship-lock and closed drainage and pumping of dam foundation.

  18. 2011 Montana Youth Risk Behavior Survey: Alternative Schools

    Science.gov (United States)

    Montana Office of Public Instruction, 2011

    2011-01-01

    This report presents the 2011 Montana Youth Risk Behavior alternative school student frequency distributions. These frequency distributions are based upon surveys with 274 alternative school students in Montana during February of 2011. Frequency distributions may not total 274 due to nonresponse and percents may not total 100 percent due to…

  19. 2011 Montana Youth Risk Behavior Survey: Students with Disabilities

    Science.gov (United States)

    Montana Office of Public Instruction, 2011

    2011-01-01

    This report presents the 2011 Montana Youth Risk Behavior Survey high school student frequency distributions for students with disabilities. These frequency distributions are based upon surveys with 1,672 high school students with disabilities in Montana during February of 2011. Frequency distributions may not total 1,672 due to nonresponse and…

  20. 76 FR 63323 - Notice of Competitive Coal Lease Sale, Montana

    Science.gov (United States)

    2011-10-12

    ...-L13200000-EL0000-P; MTM 97988] Notice of Competitive Coal Lease Sale, Montana AGENCY: Bureau of Land... described below in Musselshell County, Montana, will be offered for competitive lease by sealed bid in accordance with the provisions of the Mineral Leasing Act of 1920, as amended. DATES: The lease sale will...

  1. 77 FR 2316 - Notice of Competitive Coal Lease Sale, Montana

    Science.gov (United States)

    2012-01-17

    ... Bureau of Land Management Notice of Competitive Coal Lease Sale, Montana AGENCY: Bureau of Land... described below in Musselshell County, Montana, will be offered for competitive lease by sealed bid in accordance with the provisions of the Mineral Leasing Act of 1920, as amended. DATES: The lease sale will...

  2. Tipificación de "Arnica montana" L. (Asteraceae)

    OpenAIRE

    Ferrer Gallego, Pedro Pablo

    2014-01-01

    Se designa un lectótipo para Arnica montana L. (Asteraceae) a partir del material original de Linneo conservado en el herbario UPS-BURSER. A lectotype for Arnica montana L. (Asteraceae) is designated from Linnaeus’ original material preserved in the UPS-BURSER herbarium.

  3. Tarbela Dam Project

    Energy Technology Data Exchange (ETDEWEB)

    Khan, B.A. [WAPDA Tarbela Dam Project (Pakistan); Ahmad, W. [Siemens Pakistan Ltd., Islamabad (Pakistan)

    1999-07-01

    Construction of one of the world's largest water resource development project is discussed. The Tarbela project is built on the Indus River, (itself one of the largest rivers of the world) and consists of a 9,000 feet long and 465 feet high earth and rockfill embankment across the entire width of the river with two spillways cutting through the left bank. On the left bank valley there are two auxiliary embankment dams to close the gap. A total of five tunnels, each a mile long, have been constructed for irrigation releases and power generation. Electricity is being generated by two power generating plants constructed on three of these tunnels. They have a generating capacity of 3,478 MW, supplying 40 per cent of all Pakistani demand. Several 'firsts' are identified. For example, the dam is the world's largest, containing over 200 million cubic yards of earth and rock, as are the five tunnels (14 meters in diameter), as well as the outlet gates. The energy release by the water gushing through the five tunnels at maximum level is more than 13 million KW, approximately equivalent to 10 million horsepower. 1 ref.

  4. A Response to "A Description of Merger Applied to the Montana State University Context."

    Science.gov (United States)

    Sexton, Ronald P.; And Others

    1996-01-01

    Contains three responses to Stephen L. Coffman's article appearing in the same issue, "A Description of Merger Applied to the Montana State University Context": one from the chancellor of Montana State University-Billings, one from the president of Montana State University-Bozeman, and one from the commissioner of the Montana State University…

  5. Determination of Seepage and Analysis of Earth Dams (Case Study: Karkheh Dam)

    OpenAIRE

    A. Kamanbedast; M. Shahosseini

    2011-01-01

    Because of the increasing trend of building dam throughout Iran; it is necessary to optimize dam buildings and operations. Dam or Hydropower industry has two types of buildings; normally: (1) Concrete dams (2) Embankment (earth) dams. Generally, scientists and engineers use different methods to enhance safety and decrease any errors in calculation due to maintenance of water storage especially hydro structure of the dam. It is necessary to investigate the dam seepage control; commonly use...

  6. Prototype Evaluation of Sluiceway Aeration System Libby Dam, Kootenai River, Montana.

    Science.gov (United States)

    1984-03-01

    conducted in 1974 and a report of findings was published in 1976 (Hart and Tool 1976). With this information as reference material , WES conducted a...1 jI. AMV~V 5’ X r EkUPAENT r SNA Z’ RV4.RV2(L VU. V2) SPLITTER (TO CEN7m2 SLXV 1 ftOA rETSLUIRFm1r aula -4’ X 4’ VE-Nr RVA 4.4 65’ CEL 224025

  7. Alternatives to Dam Building: Deindustrialization and the Redevelopment of Waterways in the Northeast During the Twentieth Century

    Science.gov (United States)

    Taber, J. S.; Pompeii, B. J.; Nicoletti, C.; Lopez-Morales, C. A.

    2010-12-01

    The Northeast United States contains more dams than any other region in the country but it lacks structures on the scale of the Hoover or Bonneville dams in the American West. This work addresses why the Northeast lacks such large dams and how the pattern of small dams within the region shaped its social development. During the twentieth century, changing social and economic conditions rendered the initial purposes of many dams in the region moot, but these structures continued to influence hydrologic conditions and the provision of ecosystem services to an expanding population. The continued existence of many of these dams resulted from a worldview unable to conceive of dam removal as it did to the economic or environmental services provided by the structure. Documenting the process by which society developed alternatives to dam building in this region can contextualize the origins and contingent character of ideas about dam removal. The overarching theme in this process is the deindustrialization of the Northeast, which pitted the interests of industrial cities undergoing economic reorganization, emerging suburban communities, and growing service industries in the region. This paper considers changing attitudes toward dams as part of a four step process: (1) although the mill dams of the industrial revolution remained after electrification rendered manufacturers independent of direct water power in the early twentieth century, deindustrialization reshaped the political and legal responses to flooding by stregnthening the political and economic position of service industries and suburban residential interests; (2) the most tangible response to this development was proposed federal investment in dam building in the region between the 1930s and the 1950s; (3) political conflicts between local interests and federal proposals for dam construction slowed down the dam building process and enabled people to consider alternative strategies for flood control and power

  8. Landscape Evolution Modelling of naturally dammed rivers

    NARCIS (Netherlands)

    Gorp, van W.; Temme, A.J.A.M.; Baartman, J.E.M.; Schoorl, J.M.

    2014-01-01

    Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and

  9. Landscape Evolution Modelling of naturally dammed rivers

    NARCIS (Netherlands)

    van Gorp, Wouter; Temme, Arnaud J. A. M.; Baartman, Jantiene E. M.; Schoorl, Jeroen M.

    2014-01-01

    Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and la

  10. 76 FR 12094 - Whitman River Dam, Inc.

    Science.gov (United States)

    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... analysis at this time. n. The Crocker Dam Hydro Project would consist of: (1) The existing...

  11. FORMATION AND FAILURE OF NATURAL DAMS.

    Science.gov (United States)

    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.

  12. The Western Environmental Technology Office (WETO), Butte, Montana. Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The Western Environmental Technology Office (WETO) is a multi-purpose engineering test facility located in Butte, Montana, and is managed by MSE, Inc. WETO seeks to contribute to environmental research by emphasizing projects to develop heavy metals removal and recovery processes, thermal vitrification systems, and waste minimization/pollution prevention technologies. WETO`s environmental technology research and testing activities focus on the recovery of usable resources from waste. In one of WETO`s areas of focus, groundwater contamination, water from the Berkeley Pit, located near the WETO site, is being used in demonstrations directed toward the recovery of potable water and metal from the heavy metal-bearing water. The Berkeley Pit is part of an inactive copper mine near Butte that was once part of the nation`s largest open-pit mining operation. The Pit contains approximately 25 billion gallons of Berkeley Pit groundwater and surface water containing many dissolved minerals. As part of DOE/OST`s Resource Recovery Project (RRP), technologies are being demonstrated to not only clean the contaminated water but to recover metal values such as copper, zinc, and iron with an estimated gross value of more than $100 million. When recovered, the Berkeley Pit waters could benefit the entire Butte valley with new water resources for fisheries, irrigation, municipal, and industrial use. At WETO, the emphasis is on environmental technology development and commercialization activities, which will focus on mine cleanup, waste treatment, resource recovery, and water resource management.

  13. Big Lake Dam Inspection Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes an inspection of the Big Lake Dam that was done in September of 1983. The inspection did not reveal any conditions that constitute and...

  14. Some biological compounds, radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. sub sp. montana from Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Emre, I.; Kursat, M.; Yilmaz, O.; Erecevit, P.

    2011-07-01

    This study determined some biological compounds (fatty acid compositions, lipid-soluble vitamins, sterols, flavonoids), radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana. It was found that palmitic acid (C16:0; 8.54+-0.13-3.05+-0.04%), oleic acid (C18:1 n9, 22.41+-0.8-18.83+-0.1%) and a-inolenic acid were the dominant fatty acids in both Nepeta italica L. and Sideritis montana L. subsp. montana. It was concluded that both Nepeta italica L. and Sideritis montana L. subsp. montana contained stigmasterol and ergosterol as well as beta-sitosterol. The present findings show that Nepeta italica L. contains morin, catechin, naringin and Sideritis montana L. subsp. montana contains morin, naringenin as major flavonoids. It was also determined that methanol extracts of Nepeta italica L. and Sideritis montana L. subsp. montana were most effective against DPPH radicals. The results of the present study show that the vitamins, flavonoids and fatty acid extracts in the seeds of N. italica L. and S. montana L. subsp. montana prevented the growth of the microorganisms used in the tests at different ratios. (Author).

  15. Some biological compounds, radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana from Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Emre, I.; Kursat, M.; Yilmaz, O.; Erecevit, P.

    2011-07-01

    This study determined some biological compounds (fatty acid compositions, lipid-soluble vitamins, sterols, flavonoids), radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana. It was found that palmitic acid (C16:0; 8.54+-0.13-3.05+-0.04%), oleic acid (C18:1 n9, 22.41+-0.8-18.83+-0.1%) and a-inolenic acid were the dominant fatty acids in both Nepeta italica L. and Sideritis montana L. subsp. montana. It was concluded that both Nepeta italica L. and Sideritis montana L. subsp. montana contained stigmasterol and ergosterol as well as beta-sitosterol. The present findings show that Nepeta italica L. contains morin, catechin, naringin and Sideritis montana L. subsp. montana contains morin, naringenin as major flavonoids. It was also determined that methanol extracts of Nepeta italica L. and Sideritis montana L. subsp. montana were most effective against DPPH radicals. The results of the present study show that the vitamins, flavonoids and fatty acid extracts in the seeds of N. italica L. and S. montana L. subsp. montana prevented the growth of the microorganisms used in the tests at different ratios. (Author).

  16. Metronidazole (Flagyl) and Arnica Montana in the prevention of post-surgical complications, a comparative placebo controlled clinical trial.

    Science.gov (United States)

    Kaziro, G S

    1984-02-01

    A double blind trial, was designed, in which 118 patients undergoing the removal of impacted wisdom teeth were randomly divided into the following groups; 41 patients received Metronidazole, 39 patients received Arnica Montana, 38 patients received the placebo. Metronidazole was more effective in pain control than Arnica (p less than 0.001) and placebo (p less than 0.01). It prevented swelling better than Arnica (p less than 0.01) and placebo (p less than 0.05) and was more effective in promoting healing than Arnica (p less than 0.01) and placebo (p greater than 0.02). Arnica Montana appeared to give rise to greater pain than placebo (p less than 0.05) and caused more swelling than the placebo (p less than 0.01).

  17. Separating the mink dam from the litter at 7 or 8 weeks after delivery

    DEFF Research Database (Denmark)

    Malmkvist, Jens; Palme, Rupert; Larsen, Torben

    2015-01-01

    around the time of separation. Therefore, we investigated the effects of separating the dam from the litter, using brown first-parity dams (N=374) randomly assigned within each date of delivery to two treatment groups: The dam was taken away from the litter either at day 49 ±1 (7w, N=185) or at day 56 ±1......The optimal timing of separating the mink dam from the litter is suggested to be a balance between the partly conflicting needs of the mother and the kits. Early removal of the dam or partial removal of the litter may protect the dam against exhaustion. Little is known about the maternal motivation...... groups had an equal litter size at the time of separation (age 7w: 5.5 ±0.17; 8w: 5.5 ±0.17 kits; range 1-11; P=0.76). Likewise, there was no significant difference in dam body weight (7w: 1420 ±15.0 g, 8w: 1404 ±14.7 g; range 930-1680 g, P=0.43). However, the litter size negatively influenced both...

  18. Northwest Montana [Waterfowl Production Area] Narrative report: Fical year 1975

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines Refuge accomplishments during the 1975 fiscal year. The report begins by...

  19. Montana National Wildlife Refuges: Contaminant issues of concern

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to: (1) identify specific contaminant issues of concern for each Montana refuge and wetland management district; (2) summarize the...

  20. Montana Fish, Wildlife & Parks 2008 Avian Influenza Surveillance Project Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the work performed by Montana Fish, Wildlife and Parks (FWP) during the 2008 surveillance period. The objectives of the project were to employ...

  1. Planning and accomplishment narrative: Northwest Montana Waterfowl Production Area [1973

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This planning and accomplishments narrative report for Northwest Montana Wetland Management District outlines Refuge accomplishments during the 1973 calendar year....

  2. Building Points - Montana Structures/Addresses Framework - Web Service

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Map service for the Montana Structures MSDI Framework. The service will only display at scales of 1:100,000 or larger. Structures are grouped into general categories...

  3. Building Points - Montana Structures/Addresses Framework - Web Service

    Data.gov (United States)

    NSGIC State | GIS Inventory — Map service for the Montana Structures MSDI Framework. The service will only display at scales of 1:100,000 or larger. Structures are grouped into general categories...

  4. Land Use and Land Cover - Montana Land Cover Framework 2013

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This statewide land cover theme is a baseline digital map of Montana's natural and human land cover. The baseline map is adapted from the Northwest ReGAP project...

  5. Northwest Montana Wetland Management District : Annual Narrative : Calendar Year 1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana WMD outlines Refuge accomplishments during the 1995 calendar year. The report begins with a summary of the year's...

  6. Northwest Montana Wetland Management District : Annual Narrative : Calendar Year 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana WMD outlines Refuge accomplishments during the 1992 calendar year. The report begins with a summary of the year's...

  7. Northwest Montana Wetland Management District : Annual Narrative : Calendar Year 1994

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana WMD outlines Refuge accomplishments during the 1994 calendar year. The report begins with a summary of the year's...

  8. Northwest Montana Wetland Management District : Annual Narrative : Calendar Year 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana WMD outlines Refuge accomplishments during the 1993 calendar year. The report begins with a summary of the year's...

  9. Bone foreshafts from a clovis burial in southwestern montana.

    Science.gov (United States)

    Lahren, L; Bonnichsen, R

    1974-10-11

    Formal and functional analyses of bone artifacts from a Clovis burial in southwestern Montana suggest that they were constructed to serve as (detachable or nondetachable) foreshafts for attaching fluted projectile points to lance shafts.

  10. [Predator disease sampling results in Montana 1993-1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains data from predator disease sampling in Montana for the reintroduction of black-footed ferrets at Charles M. Russell National Wildlife Refuge....

  11. Waterfowl breeding population survey for Montana: May 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Breeding Population and Habitat Survey for Montana during 1981. The primary purpose of the survey is to provide information on...

  12. Stocking of Offsite Waters for Hungry Horse Dam Mitigation Creston National Fish Hatchery, FY 2006 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hooley, Sharon

    2009-03-20

    A total of 350,000, M012 strain, westslope cutthroat trout (WCT) eggs were received from Montana Fish Wildlife & Parks (MFWP), Washoe Park State Fish Hatchery in June of 2005 to accomplish this fishery management objective. These eggs were incubated, hatched and reared entirely inside the hatchery nursery building using a protected well water supply. Fish grew according to schedule and survival was excellent. The hatchery achieved a 0.78 feed fed to pounds gained conversion ratio for this group of WCT. Not all of the progenies from this fish lot were used for Hungry Horse Dam Fishery Mitigation Implementation. Some were used for other regional fishery management projects. Westslope cutthroat trout were reared using approved fish culture techniques as recommended in the USFWS Fish Hatchery Management Handbook and also utilizing a regimen adapted for hatchery specific site conditions. The fish health for these WCT was very good. Survival from first feeding fry stage to stocking was 79%. The hatchery had an annual fish health inspection performed by the USFWS Bozeman Fish Health Center in mid March of 2006. This inspection found all fish lots at Creston to be disease free. The Montana State Fish Health Board has placed the hatchery under a limited quarantine since May of 2005 due to an epizootic of Furunculosis. This classification has allowed the Creston NFH to stock disease free fish in locations approved by regional fish managers. The hatchery has been working with the State Fish Pathologist to remove the limited quarantine classification from the facility. Although fish health for all station fish lots remains disease free, MFWP has asserted it will not remove the limited quarantine until the new influent water treatment system, including the ultraviolet disinfection unit, is running full time, year round. The USFWS is working to secure the additional funding necessary to operate the treatment building year round. Distribution of the WCT took place from March

  13. The Marysville, Montana Geothermal Project. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    1975-09-01

    This report describes the exploration of an anomalous site near Marysville, Montana, where the geothermal heat flow is about 10 times the regional average. The site arouses scientific interest because there are no surface manifestations such as young volcanics, hot springs, geysers, etc., within 20 miles of it. Also, there is significant economic interest in exploring the source of heat as a potential for the generation of electricity. Included herein are independent sections prepared by each contractor. Consequently, there is some overlapping information, generally presented from different viewpoints. The project consists of geophysical surveys in 1973 and 1974, the drilling of the deep well in the summer of 1974 to a depth of 6790 feet, the coring and logging of the well, the supporting scientific studies, and the data analysis. Since so much data are available on the Marysville system, it can serve as a testing and research area to help locate and understand similar systems. (GRA)

  14. US hydropower resource assessment for Montana

    Energy Technology Data Exchange (ETDEWEB)

    Francfort, J.E.

    1993-12-01

    The Department of Energy is developing an estimate of the hydropower development potential in this country. The Hydropower Evaluation Software (HES) is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The HES measures the potential hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a dBASE menu-driven software application that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the state of Montana.

  15. Damming the rivers of the Amazon basin

    Science.gov (United States)

    Latrubesse, Edgardo M.; Arima, Eugenio Y.; Dunne, Thomas; Park, Edward; Baker, Victor R.; D'Horta, Fernando M.; Wight, Charles; Wittmann, Florian; Zuanon, Jansen; Baker, Paul A.; Ribas, Camila C.; Norgaard, Richard B.; Filizola, Naziano; Ansar, Atif; Flyvbjerg, Bent; Stevaux, Jose C.

    2017-06-01

    More than a hundred hydropower dams have already been built in the Amazon basin and numerous proposals for further dam constructions are under consideration. The accumulated negative environmental effects of existing dams and proposed dams, if constructed, will trigger massive hydrophysical and biotic disturbances that will affect the Amazon basin’s floodplains, estuary and sediment plume. We introduce a Dam Environmental Vulnerability Index to quantify the current and potential impacts of dams in the basin. The scale of foreseeable environmental degradation indicates the need for collective action among nations and states to avoid cumulative, far-reaching impacts. We suggest institutional innovations to assess and avoid the likely impoverishment of Amazon rivers.

  16. Dam risk assistant analysis system design

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to reduce the labor intensity and task difficulty of dam risk analysis and to meet the actual requirement of dam risk analysis,it is necessary to establish a dam risk assistant analysis system.The program structure and the implementation ways of the dam risk assistant analysis system are analyzed,and a procedural framework with "three-tier and multi-database" structure and "level structure" is established.The concept of dam risk assessment system modular development is proposed and the coupled mode of function module and data is improved.Finally,the dam risk assistant analysis system is developed using Delphi visual programming language.

  17. Montana StreamStats—A method for retrieving basin and streamflow characteristics in Montana: Chapter A in Montana StreamStats

    Science.gov (United States)

    McCarthy, Peter M.; Dutton, DeAnn M.; Sando, Steven K.; Sando, Roy

    2016-04-05

    The U.S. Geological Survey (USGS) provides streamflow characteristics and other related information needed by water-resource managers to protect people and property from floods, plan and manage water-resource activities, and protect water quality. Streamflow characteristics provided by the USGS, such as peak-flow and low-flow frequencies for streamflow-gaging stations, are frequently used by engineers, flood forecasters, land managers, biologists, and others to guide their everyday decisions. In addition to providing streamflow characteristics at streamflow-gaging stations, the USGS also develops regional regression equations and drainage area-adjustment methods for estimating streamflow characteristics at locations on ungaged streams. Regional regression equations can be complex and often require users to determine several basin characteristics, which are physical and climatic characteristics of the stream and its drainage basin. Obtaining these basin characteristics for streamflow-gaging stations and ungaged sites traditionally has been time consuming and subjective, and led to inconsistent results.StreamStats is a Web-based geographic information system application that was created by the USGS to provide users with access to an assortment of analytical tools that are useful for water-resource planning and management. StreamStats allows users to easily obtain streamflow and basin characteristics for USGS streamflow-gaging stations and user-selected locations on ungaged streams. The USGS, in cooperation with Montana Department of Transportation, Montana Department of Environmental Quality, and Montana Department of Natural Resources and Conservation, completed a study to develop a StreamStats application for Montana, compute streamflow characteristics at streamflow-gaging stations, and develop regional regression equations to estimate streamflow characteristics at ungaged sites. Chapter A of this Scientific Investigations Report describes the Montana Stream

  18. Douglas County Dam Breach Inundation Areas

    Data.gov (United States)

    Kansas Data Access and Support Center — Dam breach analysis provides a prediction of the extent and timing of flooding from a catastrophic breach of the dams. These results are sufficient for developing...

  19. VT High Risk Dam Inundation Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) Preliminary release Storm-Day dam inundation areas digitized from various source Emergency Action Plans. These dams were prioritized for...

  20. Dams and Obstructions along Iowa's Canoe Routes

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This dataset represents obstruction to canoe and boat users of the canoe routes of Iowa. This may represent actual dams, rock dams (natural or man made), large...

  1. 75 FR 57059 - Montana Department of Natural Resources and Conservation Final Habitat Conservation Plan and...

    Science.gov (United States)

    2010-09-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Montana Department of Natural Resources and Conservation Final Habitat... received from the Montana Department of Natural Resources and Conservation (DNRC) a Final...

  2. 77 FR 12581 - Public Water System Supervision Program Revision for the State of Montana

    Science.gov (United States)

    2012-03-01

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Public Water System Supervision Program Revision for the State of Montana AGENCY: Environmental... the state of Montana has revised its Public Water System Supervision (PWSS) Program by...

  3. 75 FR 69434 - Public Water System Supervision Program Revision for the State of Montana

    Science.gov (United States)

    2010-11-12

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Public Water System Supervision Program Revision for the State of Montana AGENCY: Environmental... the State of Montana has revised its Public Water System Supervision (PWSS) Primacy Program...

  4. The Montana Wild Virus Hunt | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... Health: The Montana Wild Virus Hunt Follow us The Montana Wild Virus Hunt Blake Wiedenheft is a ... their passion for health and science. What is the focus of your research? Viruses that infect bacteria ( ...

  5. Historic human impact on low order mountain streams - what role did the dams play?

    Science.gov (United States)

    Larsen, Annegret; Fuelling, Alexander; Wilder, Nicole; Bork, Hans-Rudolf; Larsen, Joshua R.

    2014-05-01

    The historic damming of central European rivers is extensive, with the highest density concentrated on low-order streams. Construction of dams started mostly in medieval times (~ 1200 years ago) and peaked in the early nineteenth century, resulting in shifting dam densities with different ages and types. Early dams were mainly build for energy , but later their primary purpose shifted to floodplain irrigation . This legacy highlights the intense alteration of small streams by humans in a short time period relative to their Holocene evolution. However, our understanding of the impact of such high number of dams on the ecology, river morphology and sediment storage over longer time periods remains very limited. This knowledge gap becomes critical to address as dam removal and river restoration expands under the implementation of the Water Framework Directive, a European-wide legislative framework. In order to explore the possible effects of this framework on small order streams, we examine the changes that have occurred to a fluvial system since the onset of historic dam building. We combine the analysis of historic maps, chrono-stratigraphy and hydraulic modeling to understand the influence of the large number of dams along the low-order streams in two representative mountain catchments of 3rd and 4th order streams (Elsava and Sinn river in the Spessart and Rhön mountains, Germany). The datings and stratigraphical analysis indicate that the rivers were likely influenced by valley bottom damming before hillslope agriculture caused erosion and an increase of sediment delivery to the streams. Future work will examine the hydraulic behavior of the streams with and without dams in order to better understand their role in floodplain development.

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

    Science.gov (United States)

    2013-08-29

    ... Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams AGENCY: Tennessee... preferred alternative in its final environmental impact statement (EIS) for the dam safety modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams. The notice of availability (NOA) of the...

  7. Developing a Climate Change Boundary Organization: the Montana Adaptation Exchange

    Science.gov (United States)

    Whitlock, C. L.; Brooks, S.; Armstrong, T.; Bryan, B.

    2016-12-01

    Small-population large-area states like Montana are often challenged by a need to offer timely and relevant climate-change information that addresses diverse and widely dispersed stakeholder groups. In Montana, filling the gap between science and various types of decision-makers has motivated development of the first Montana Climate Assessment (MCA1), to be released in 2017 with a focus on climate-change impacts for agricultural, water and forestry sectors. To sustain and build on the MCA1 effort, we are also in the process of creating a Boundary Organization (defined by the National Academy of Sciences) called the Montana Adaptation Exchange (the Exchange); this entity will facilitate the flow of information across the boundaries between science, knowledge and implementation. In Montana, the Exchange brings scientists and practitioners together to seek solutions related to climate-change adaptation and other pressing environmental and social-economic challenges. The Montana Adaptation Exchange (1) is a collaborative partnership of members from the science and practitioner communities under a shared governance and participatory model; (2) presents research that has been vetted by the scientific community at large and represents the current state of knowledge; (3) allows for revision and expansion of assessments like the MCA; (4) communicates relevant, often technical, research and findings to a wide variety of resource managers and other stakeholders; (5) develops and maintains an extensive online database that organizes, regularly updates, and makes research data products readily available; and (6) offers an online portal and expert network of affiliated researchers and climate adaptation specialists to provide effective customer support. Boundary organizations, such as the Montana Adaptation Exchange, offer a scalable path to effectively move from "science to knowledge to action" while also allowing stakeholder needs to help inform research agendas.

  8. EVALUASI KEAMANAN DAM JATILUHUR BERBASIS INDEKS RESIKO

    Directory of Open Access Journals (Sweden)

    Avazbek Ishbaev

    2014-12-01

    Full Text Available The dams have very important roles to agricultural activities. Especially, West Java with 240,000 hectares of agricultural land, needs a good dam structure that can be used sustainably. Jatiluhur dam in Purwakarta, West Java is one of big dams in Indonesia which has important rules not only for Purwakarta but also for Jakarta, Karawang and Bekasi residents. A study and observation about safety and dam stability is needed to prevent any damage. The purpose of this research were to identify parameters that influenced dam safety and to evaluate dam reliability based on index tools. Analysis was done using risk index tools. The result showed that the condition of the dam of Jatiluhur is still satisfied with indicators, "Idam"-750. The total index risk was 127.22 and the safety factor was 83.04 out of 100. Therefore, Jatiluhur dam could be classified as safe and no need for particular treatments. Jatiluhur dam can be operated in normal condition or abnormal condition with periodic monitoring. Keywords: dam safety, evaluation, Jatiluhur Dam, risk index tools

  9. Webinar: Stepped chute design for embankment dams

    Science.gov (United States)

    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...

  10. Dams life; La vie des barrages

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The paper reports on the conclusions of decennial and annual inspections of French dams. Dams surveillance is performed by the operators and consists in visual examinations and measurements. Concrete dams, in particular, always have more or less developed fissures with water sweating threw the concrete mass or the foundations. Old concrete often show low swelling phenomena which are measured too. (J.S.)

  11. Dam-induced and natural channel changes in the Saskatchewan River below the E.B. Campbell Dam, Canada

    Science.gov (United States)

    Smith, Norman D.; Morozova, Galina S.; Pérez-Arlucea, Marta; Gibling, Martin R.

    2016-09-01

    The E.B. Campbell Dam on the Saskatchewan River, east-central Saskatchewan, was constructed in 1962, forming Tobin Lake (2.2 billion m3 capacity), which today impounds most fluvial sediment and disrupts normal outflow patterns. Thirty-five kilometers below the dam, the river diverts into a 500 km2 belt of alluvial sediment initiated by an avulsion 140 years ago, rejoining the parent channel 108 km from the dam. Effects of the dam on channel geomorphology, including the historical channel (reach I) and the more recent avulsion-affected channels, were investigated by pre- and post-dam cross section surveys combined with grain-size and bedload measurements. Twenty-three sites were surveyed at least twice, and 14 were resurveyed annually in 2003-2014 (except 2007) during which significant floods occurred in 2005, 2011, and 2013. All channel cross sections up to 81 km below the dam have coarsened and enlarged since closure, resulting in excavation of 35.4 × 106 m3 of channel-perimeter sediment since 1962. The most proximal segment is armored and has changed little in recent years. Since 2003, channel enlargement has been greatest in the 35-81 km segment between the avulsion site and the Forks (reaches II, III), manifested as widening and deepening. Enlargement rates were greatest during the three floods, and the paucity of bedload has prevented degraded portions of the channel bed from replenishment following flooding. Budget calculations based on bedload measurements and channel cross-section areas suggest that > 30 years would be required to replace the sediment removed between 2003 and 2014, assuming all available bedload remains in the affected reach. Dam effects appear to be absent or uncertain beyond 81 km, a multichanneled region of varied stages of activity (reach IV), recombining and eventually rejoining the parent Saskatchewan River channel at km 108 (reach V). Sediment evacuated from reaches I-III is sufficient to sustain modest aggradation in some distal

  12. The formation and failure of natural dams

    Science.gov (United States)

    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

  13. Yearling mink dams fed restricted in early lactation have less mammary gland tissue six weeks after birth

    DEFF Research Database (Denmark)

    Møller, Steen Henrik; Pinkalski, Mariann Nakano

    2015-01-01

    The optimal timing of separating the mink dam from the litter is suggested to be a balance between the partly conflicting needs of the mother and the kits. Early removal of the dam or partial removal of the litter may protect the dam against exhaustion. Little is known about the maternal motivation...... around the time of separation. Therefore, we investigated the effects of separating the dam from the litter, using brown first-parity dams (N=374) randomly assigned within each date of delivery to two treatment groups: The dam was taken away from the litter either at day 49 ±1 (7w, N=185) or at day 56 ±1...... (8w, N=189) after birth. The aim was to investigate whether the dams had a different motivation to take care of the litter after 7 and 8 weeks, estimated by non-invasive determination of cortisol (FCM: Faecal Corticsol Metabolites) and dam calls the first week after separation. The two treatment...

  14. Surprise and Opportunity for Learning in Grand Canyon: the Glen Canyon Dam Adaptive Management Program

    Directory of Open Access Journals (Sweden)

    Theodore S. Melis

    2015-09-01

    Full Text Available With a focus on resources of the Colorado River ecosystem below Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Program has included a variety of experimental policy tests, ranging from manipulation of water releases from the dam to removal of non-native fish within Grand Canyon National Park. None of these field-scale experiments has yet produced unambiguous results in terms of management prescriptions. But there has been adaptive learning, mostly from unanticipated or surprising resource responses relative to predictions from ecosystem modeling. Surprise learning opportunities may often be viewed with dismay by some stakeholders who might not be clear about the purpose of science and modeling in adaptive management. However, the experimental results from the Glen Canyon Dam program actually represent scientific successes in terms of revealing new opportunities for developing better river management policies. A new long-term experimental management planning process for Glen Canyon Dam operations, started in 2011 by the U.S. Department of the Interior, provides an opportunity to refocus management objectives, identify and evaluate key uncertainties about the influence of dam releases, and refine monitoring for learning over the next several decades. Adaptive learning since 1995 is critical input to this long-term planning effort. Embracing uncertainty and surprise outcomes revealed by monitoring and ecosystem modeling will likely continue the advancement of resource objectives below the dam, and may also promote efficient learning in other complex programs.

  15. A Comparison of Three Rubber Dam Systems in Vivo: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Martin Kapitán

    2015-07-01

    Full Text Available The aim of this study was to compare the isolation systems OptraDam® Plus and OptiDam™ with the conventional rubber dam in terms of objective and subjective parameters. The isolation systems were applied during the dental treatment of the patients. The time of preparation, placement, presence and removal were measured and the quality of isolation was evaluated. The median time of rubber dam placement was 76 s (Q1 = 62 s; Q3 = 111.25 s. The application time of OptraDam® Plus was significantly longer compared to the other systems (P < 0.001. The median volume of fluid remaining in the isolated space after 5 minutes was 4.9 mL (Q1 = 4 mL; Q3 = 5 mL. The differences between the systems with regards to isolation quality were not statistically significant. The majority of the patients reported a higher level of comfort during the treatment with a rubber dam than without it. The attitude of patients was not affected by any of the observed factors. The ranking of the isolation systems according to the subjective evaluation by the patients was (from best to worst OptiDam™, conventional rubber dam, OptraDam® plus. The results presented in this study could guide clinicians for choosing the most appropriate isolation system.

  16. Mercury Emission Control Technologies for PPL Montana-Colstrip Testing

    Energy Technology Data Exchange (ETDEWEB)

    John P. Kay; Michael L. Jones; Steven A. Benson

    2007-04-01

    The Energy & Environmental Research Center (EERC) was asked by PPL Montana LLC (PPL) to provide assistance and develop an approach to identify cost-effective options for mercury control at its coal-fired power plants. The work conducted focused on baseline mercury level and speciation measurement, short-term parametric testing, and week long testing of mercury control technology at Colstrip Unit 3. Three techniques and various combinations of these techniques were identified as viable options for mercury control. The options included oxidizing agents or sorbent enhancement additives (SEAs) such as chlorine-based SEA1 and an EERC proprietary SEA2 with and without activated carbon injection. Baseline mercury emissions from Colstrip Unit 3 are comparatively low relative to other Powder River Basin (PRB) coal-fired systems and were found to range from 5 to 6.5 g/Nm3 (2.9 to 3.8 lb/TBtu), with a rough value of approximately 80% being elemental upstream of the scrubber and higher than 95% being elemental at the outlet. Levels in the stack were also greater than 95% elemental. Baseline mercury removal across the scrubber is fairly variable but generally tends to be about 5% to 10%. Parametric results of carbon injection alone yielded minimal reduction in Hg emissions. SEA1 injection resulted in 20% additional reduction over baseline with the maximum rate of 400 ppm (3 gal/min). Week long testing was conducted with the combination of SEA2 and carbon, with injection rates of 75 ppm (10.3 lb/hr) and 1.5 lb/MMacf (40 lb/hr), respectively. Reduction was found to be an additional 30% and, overall during the testing period, was measured to be 38% across the scrubber. The novel additive injection method, known as novel SEA2, is several orders of magnitude safer and less expensive than current SEA2 injection methods. However, used in conjunction with this plant configuration, the technology did not demonstrate a significant level of mercury reduction. Near-future use of this

  17. Research on shape optimization of CSG dams

    Directory of Open Access Journals (Sweden)

    Xin CAI

    2011-12-01

    Full Text Available The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum settlement of the dam to water level changes, the overall stability, and the overall strength security were taken into account during the optimization process. Three weight coefficient selection schemes were adopted to conduct shape optimization of a dam, and the case studies lead to the conclusion that both the upstream and downstream dam slope ratios for the optimal cross-section equal 1:0.7, which is consistent with the empirically observed range of 1:0.6 to 1:0.8 for the upstream and downstream dam slope ratios of CSG dams. Therefore, the present study is of certain reference value for designing CSG dams.

  18. Future directions of dam safety in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Verzeni, Gerard [Hydro Quebec, QC, (Canada)

    2010-07-01

    Gerard Verzeni, former director of the dam safety & environment at Hydro-Quebec introduced the future directions of dam safety in Canada. New and numerous challenges are emerging for the dam safety community. Measurable effects of climate changes illustrate that hydraulic forecasts would change drastically. Loads with times and amplitudes which are different from the actual knowledge will apply on dams. The development of new types of dams using recent technologies raises several issues, for example the longevity of such installations. The installations are becoming old and soon will require complete renovation and update for regulation and standards compliance. Concrete dams already need efforts and investment to maintain then in a safe state. Various factors will influence these challenges such as human resources in the dam safe community. In these conditions, it is important that organizations like CDA play an important role in providing support and reference and in being a driver for the whole industry.

  19. Travel Times, Streamflow Velocities, and Dispersion Rates in the Yellowstone River, Montana

    Science.gov (United States)

    McCarthy, Peter M.

    2009-01-01

    The Yellowstone River is a vital natural resource to the residents of southeastern Montana and is a primary source of water for irrigation and recreation and the primary source of municipal water for several cities. The Yellowstone River valley is the primary east-west transportation corridor through southern Montana. This complex of infrastructure makes the Yellowstone River especially vulnerable to accidental spills from various sources such as tanker cars and trucks. In 2008, the U.S. Geological Survey (USGS), in cooperation with the Montana Department of Environmental Quality, initiated a dye-tracer study to determine instream travel times, streamflow velocities, and dispersion rates for the Yellowstone River from Lockwood to Glendive, Montana. The purpose of this report is to describe the results of this study and summarize data collected at each of the measurement sites between Lockwood and Glendive. This report also compares the results of this study to estimated travel times from a transport model developed by the USGS for a previous study. For this study, Rhodamine WT dye was injected at four locations in late September and early October 2008 during reasonably steady streamflow conditions. Streamflows ranged from 3,490 to 3,770 cubic feet per second upstream from the confluence of the Bighorn River and ranged from 6,520 to 7,570 cubic feet per second downstream from the confluence of the Bighorn River. Mean velocities were calculated for each subreach between measurement sites for the leading edge, peak concentration, centroid, and trailing edge at 10 percent of the peak concentration. Calculated velocities for the centroid of the dye plume for subreaches that were completely laterally mixed ranged from 1.83 to 3.18 ft/s within the study reach from Lockwood Bridge to Glendive Bridge. The mean of the completely mixed centroid velocity for the entire study reach, excluding the subreach between Forsyth Bridge and Cartersville Dam, was 2.80 ft/s. Longitudinal

  20. Karyomorphometric analysis of Fritillaria montana group in Greece

    Directory of Open Access Journals (Sweden)

    Sofia Samaropoulou

    2016-12-01

    Full Text Available Fritillaria Linnaeus, 1753 (Liliaceae is a genus of geophytes, represented in Greece by 29 taxa. Most of the Greek species are endemic to the country and/or threatened. Although their classical cytotaxonomic studies have already been presented, no karyomorphometric analysis has ever been given. In the present study, the cytological results of Fritillaria montana Hoppe ex W.D.J. Koch, 1832 group, which includes F. epirotica Turrill ex Rix, 1975 and F. montana are statistically evaluated for the first time. Further indices about interchromosomal and intrachromosomal asymmetry are given. A new population of F. epirotica is also investigated, while for F. montana, a diploid individual was found in a known as triploid population. Paired t-tests and PCoA analysis have been applied to compare the two species.

  1. Study of Dam-break Due to Overtopping of Four Small Dams in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Zakaraya Alhasan

    2015-01-01

    Full Text Available Dam-break due to overtopping is one of the most common types of embankment dam failures. During the floods in August 2002 in the Czech Republic, several small dams collapsed due to overtopping. In this paper, an analysis of the dam break process at the Luh, Velký Bělčický, Melín, and Metelský dams breached during the 2002 flood is presented. Comprehensive identification and analysis of the dam shape, properties of dam material and failure scenarios were carried out after the flood event to assemble data for the calibration of a numerical dam break model. A simple one-dimensional mathematical model was proposed for use in dam breach simulation, and a computer code was compiled. The model was calibrated using the field data mentioned above. Comparison of the erodibility parameters gained from the model showed reasonable agreement with the results of other authors.

  2. Management of dams for the next Millennium: proceedings of the 1999 Canadian Dam Association

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    The meeting featured seven sessions with 18 papers abstracted/indexed therein as follows: keynote address: tailings dams safety - implications for the dam safety community; 1 - design and performance: performance monitoring of dams: are we doing what we should be doing?; tailings dams from the perspective of conventional dam engineering; and design overview of Syncrude's Mildred Lake east toe berm; 2 - design and modelling: use of a 2D model for a dam break study on the ALCAN hydroelectric complex in Quebec; and spillway design implications resulting from changes in rainfall extremes; 3 - risk and dam safety I: closing the gaps in the dam safety guidelines; the reality of life safety consequence classification; and surveillance practices for the next millenium; 4 - risk and dam safety II: quantitative risk-assessment using the capacity-demand analysis; and new guidelines for dam safety classification; 5 - millenium issues: expectations of immortality, dam safety management into the next millenium; 6 - rehabilitation techniques: the unconventional application of conventional materials; nondestructive testing technology to characterize concrete dam/bedrock interface; method and instrument for detecting crack in concrete; and grouting of the cracks in the Arch 5-6 - Daniel Johnson Dam; and 7 - case studies: rehabilitation of an 80 year old Ambursen type dam; and debris booms for the protection of spillways.

  3. Effects of Chiloquin Dam on spawning distribution and larval emigration of Lost River, shortnose, and Klamath largescale suckers in the Williamson and Sprague Rivers, Oregon

    Science.gov (United States)

    Martin, Barbara A.; Hewitt, David A.; Ellsworth, Craig M.

    2013-01-01

    Chiloquin Dam was constructed in 1914 on the Sprague River near the town of Chiloquin, Oregon. The dam was identified as a barrier that potentially inhibited or prevented the upstream spawning migrations and other movements of endangered Lost River (Deltistes luxatusChasmistes brevirostris) suckers, as well as other fish species. In 2002, the Bureau of Reclamation led a working group that examined several alternatives to improve fish passage at Chiloquin Dam. Ultimately it was decided that dam removal was the best alternative and the dam was removed in the summer of 2008. The U.S. Geological Survey conducted a long-term study on the spawning ecology of Lost River, shortnose, and Klamath largescale suckers (Catostomus snyderi) in the Sprague and lower Williamson Rivers from 2004 to 2010. The objective of this study was to evaluate shifts in spawning distribution following the removal of Chiloquin Dam. Radio telemetry was used in conjunction with larval production data and detections of fish tagged with passive integrated transponders (PIT tags) to evaluate whether dam removal resulted in increased utilization of spawning habitat farther upstream in the Sprague River. Increased densities of drifting larvae were observed at a site in the lower Williamson River after the dam was removed, but no substantial changes occurred upstream of the former dam site. Adult spawning migrations primarily were influenced by water temperature and did not change with the removal of the dam. Emigration of larvae consistently occurred about 3-4 weeks after adults migrated into a section of river. Detections of PIT-tagged fish showed increases in the numbers of all three suckers that migrated upstream of the dam site following removal, but the increases for Lost River and shortnose suckers were relatively small compared to the total number of fish that made a spawning migration in a given season. Increases for Klamath largescale suckers were more substantial. Post-dam removal monitoring

  4. Flavonoids from the aerial parts of Onobrychis montana subsp. scardica

    Directory of Open Access Journals (Sweden)

    BORIS PEJIN

    2008-05-01

    Full Text Available Rutin (1, main constituent and two flavone C-glycosides, vitexin (2 and vitexin 2''-O-alpha-rhamnopyranoside (3 were isolated from the aerial parts of Onobrychis montana subsp. scardica. They were identified by 1H-NMR, 13C-NMR and UV–Vis spectroscopy (procedure with shift reagents, and high resolution ESI-MS. A relatively high content of 1 (5.27 mg/g of dry plant material, measured by HPLC, indicated O. montana subsp. scardica as a new natural source of this biologically active compound. The isolated flavonoid compounds might be of value as chemotaxonomic markers.

  5. Methods for estimating streamflow characteristics at ungaged sites in western Montana based on data through water year 2009: Chapter G in Montana StreamStats

    Science.gov (United States)

    McCarthy, Peter M.; Sando, Roy; Sando, Steven K.; Dutton, DeAnn M.

    2016-04-05

    The U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality and the Montana Department of Natural Resources and Conservation, developed regional regression equations based on basin and streamflow characteristics for streamflow-gaging stations through water year 2009 that can be used to estimate streamflow characteristics for ungaged sites in western Montana. The regression equations allow estimation of low-flow frequencies; mean annual and mean monthly streamflows; and the 20-, 50-, and 80-percent durations for annual and monthly duration streamflows for ungaged sites in western Montana that are unaffected by regulation.

  6. HOW DAMS VARY AND WHY IT MATTERS FOR THE EMERGING SCIENCE OF DAM REMOVAL. (R828636)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  7. Brazil's Amazonian dams: Ecological and socioeconomic impacts

    Science.gov (United States)

    Fearnside, P. M.

    2016-12-01

    Brazil's 2015-2024 Energy Expansion Plan calls for 11 hydroelectric dams with installed capacity ≥ 30 MW in the country's Amazon region. Dozens of other large dams are planned beyond this time horizon, and dams with consumers. Population displacement is a major impact; for example, the Marabá Dam would displace 40,000 people, mostly traditional riverside dwellers (ribeirinhos). Various dams impact indigenous peoples, such as the Xingu River dams (beginning with Belo Monte) and the São Luiz do Tapajós and Chacorão Dams on the Tapajós River. Brazil has many energy options other than dams. Much energy use has little benefit for the country, such as exporting aluminum. Electric showerheads use 5% of the country's power. Losses in transmission lines (20%) are far above global averages and can be expected to increase as Amazonian hydroelectric dams far from consumer centers come on line. Brazil has tremendous wind and solar potential, but these do not have the same priority as dams. At the root of many questionable policies is a decision-making process in need of reform.

  8. DAM REMOVAL: PANACEA OR PANDORA FOR RIVERS? (R825822)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  9. Modelli di comportamento espressi dagli studenti della Comunitá Montana 'Canal del Ferro Val Canale' (UD nei confronti delle bevande alcoliche e del fumo di tabacco.

    Directory of Open Access Journals (Sweden)

    G.B. Modonutti

    2003-05-01

    Full Text Available

    Nell’intento di definire le modalità di approccio, le abitudini, il background culturale e la percezione dei rischi associati all’uso delle bevande alcoliche e del fumo di tabacco dei giovani nelle diverse realtà socioeconomiche e culturali del Friuli Venezia Giulia, il Gruppo di Ricerca per l’Educazione alla Salute (GRES, utilizzando una Scheda Questionario anonima, autosomministrata, semistrutturata, ha condotto, nel corso del 2002, una ricerca sugli stili di vita di 280 studenti (M: 56.8%; F: 43.2% della Scuola Media di 1° della Comunità Montana “Canal del Ferro Val Canale” (UD. Gli studenti bevitori costituiscono il 27.1% della popolazione scolastica coinvolta (M: 28.3%; F: 25.6%, consumano mediamente 6.9g/die di alcol anidro che assumono per il 57.2% della Dieta Alcolica Media (DAM pasteggiando (M: 72.7%DAM; F: 50.9%DAM, i maschi bevendo prevalentemente vino (41.2%DAM, le femmine con i superalcolici (57.1%DAM. Beve alcolici “abitualmente” il 7.1% della popolazione studentesca (M: 6.9%; F: 7.4%, il 2.1% è esposto per il proprio bere quotidiano a maggior rischio di problemi Psico Medico Sociali (M: 1.3%; F: 2.3% e l’8.9% afferma di aver sperimentato nel corso dell’ultimo anno l’Intossicazione Acuta da Alcol (M: 10.7%; F: 7.4%. Gli studenti fumatori sono il 9.6% della popolazione scolastica (M: 10.1%; F: 9.1%, consumano in media 5.6 sig/die (M: 2.2sig/die; F: 10.6sig/die; p‹0.05 ed il 6.8% degli studenti contattati, insensibili alle raccomandazioni che sconsigliano qualsiasi utilizzo del fumo di tabacco alla popolazione in età pediatrica, fumano mediamente 1 o più sigarette al giorno (M: 6.3%; F: 7.4%.

    I modelli di comportamento e la percezione dei rischi associati all’uso degli alcolici e del tabacco espressi dagli studenti della Comunità Montana “Canal del Ferro Val Canale” (UD costituiscono motivo di preoccupazione per la salute dei giovani ed uno stimolo alla programmazione ed attuazione di

  10. Comparison of Natural Dams from Lava Flows and Landslides on the Owyhee River, Oregon

    Science.gov (United States)

    Ely, L. L.; Brossy, C. C.; Othus, S. M.; Orem, C.; Fenton, C.; House, P. K.; O'Connor, J. E.; Safran, E. B.

    2008-12-01

    Numerous large lava flows and mass movements have temporarily dammed the Owyhee River in southeastern Oregon at various temporal and spatial scales. These channel-encroaching events potentially play a significant role in creating and maintaining the geomorphic features of river canyons in uplifted volcanic terranes that compose a significant part of the western U.S. Abundant landslides and lava flows have the capacity to inhibit incision by altering channel slope, width, and bed character, and burying valley- bottom bedrock under exogenous material; or promote incision by generating cataclysmic floods through natural dam failures. The natural dams vary in their source, morphology, longevity and process of removal, which in turn affects the extent and duration of their impact on the river. The 3 most recent lava flows filled the channel 10-75 m deep and flowed up to 26 kilometers downvalley, creating long, low dams that were subject to gradual, rather than catastrophic, removal. In the last 125 ka, the Saddle Butte and West Crater lava dams created reservoirs into which 10-30 meters of silt and sand were deposited. The river overtopped the dams and in most reaches eventually cut a new channel through the adjacent, less resistant bedrock buttresses. Terraces at several elevations downstream and upstream of the West Crater dam indicate periods of episodic incision ranging from 0.28 to 1.7 mm/yr., based on 3He exposure ages on strath surfaces and boulder-rich fluvial deposits. In contrast to the lava dams, outburst flood deposits associated with landslide dams are common along the river. The mechanisms of failure are related to the geologic setting, and include rotational slump complexes, cantilevered blocks and block slides, and massive earthflows. Most large-scale mass movements occur in reaches where the Owyhee canyon incises through stacks of interbedded fluviolacustrine sediments capped with lava flows. The frequently observed association of landslides and flood

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

    Science.gov (United States)

    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.

  12. Dam safety review, classification of dams for the Novia Scotia Power Inc. Black River hydroelectric system

    Energy Technology Data Exchange (ETDEWEB)

    Alderman, Aaron; Small, Andy [AMEC Earth and environmental, Fredericton, (Canada); O' Neil, Ellis [Nova Scotia Power Inc., Halifax, (Canada)

    2010-07-01

    In 2009, AMEC was retained by Nova Scotia Power Inc. (NSPI) to conduct a dam safety review of the dams that are part of the Black River Hydroelectric System. This paper presented the results of this dam classification exercise which was carried out for the Bear River hydroelectric system in Nova Scotia, based on the 2007 Canadian Dam Association (CDA) dam safety guidelines. Flood mapping and dam-break analysis were performed for events ranging from the 1:100 year to PMF flood events, including cascading events. These results were used to draw up a classification of the dams. Associated design criteria were then developed. Following the assessment of the dam sites, conclusions and recommendations were discussed. The recommendations were presented in terms of regular maintenance items and reconstruction items, which are now used by NSPI to determine the party responsible for undertaking the recommendation and for evaluation of the maintenance and reconstruction schedules.

  13. Dam Inventory, dams, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'dams'. Data...

  14. 2011 Montana Youth Risk Behavior Survey: Nonpublic Accredited Schools

    Science.gov (United States)

    Montana Office of Public Instruction, 2011

    2011-01-01

    This report presents the 2011 Montana Youth Risk Behavior Survey high school student frequency distributions for nonpublic accredited schools. These frequency distributions are based upon surveys with 349 high school students in Nonpublic Region during February of 2011. Frequency distributions may not total 349 due to nonresponse and percents may…

  15. A new fauna from the Colorado group of southern Montana

    Science.gov (United States)

    Reeside, John B.

    1925-01-01

    This paper describes a small but interesting fauna collected in 1921 by W. T. Thorn, Jr., Gail F. Moulton, T. W. Stanton, and K. C. Heald in the Crow Indian Reservation in southern Montana. The locality is in sec. 36, T. 6 S., R. 32 E., Big Horn County, and is 2 miles east of the Soap Creek oil field.

  16. American Indian High School Completion in Rural Southeastern Montana.

    Science.gov (United States)

    Ward, Carol

    1995-01-01

    Factors related to dropping out were examined among Northern Cheyenne and Crow high school students living in three southeastern Montana communities and attending a Catholic school, a public school, or a tribal school. Place of residence, parental educational attainment, and school experiences were important variables, but their effects varied by…

  17. Thymol derivatives from hairy roots of Arnica montana.

    Science.gov (United States)

    Weremczuk-Jezyna, I; Kisiel, W; Wysokińska, H

    2006-09-01

    Five known thymol derivatives were isolated from roots of Arnica montana transformed with Agrobacterium rhizogenes LBA 9402. The compounds were characterized by spectral methods. The pattern of thymol derivatives in light-grown hairy roots was slightly different from that in dark-grown ones. This is the first report on the presence of thymol derivatives in hairy roots of the plant.

  18. Methylated Flavonoids from Arnica montana and Arnica chamissonis.

    Science.gov (United States)

    Merfort, I

    1984-02-01

    From the flowers of ARNICA CHAMISSONIS Less, subsp. FOLIOSA var. INCANA, the methylated flavonoids acacetin, pectolinarigenin, hispidulin, jaceosidin, 6-methoxykaempferol, and betuletol have been isolated and identified by spectroscopic methods. Except for acacetin, the same flavonoids were identified in the flowers of ARNICA MONTANA L. Betuletol was found for the first time in the family of Asteraceae.

  19. On-site energy consumption at softwood sawmills in Montana

    Science.gov (United States)

    Dan Loeffler; Nathaniel Anderson; Todd A. Morgan; Colin B. Sorenson

    2016-01-01

    Total on-site energy requirements for wood product manufacturing are generally not well understood or publicly available, particularly at subregional scales, such as the state level. This article uses a mail survey of softwood sawmills in Montana to develop a profile of all on-site energy consumption. Energy use is delineated by fuel type on a production basis...

  20. Essential oil of Arnica montana and Arnica chamissonis

    Directory of Open Access Journals (Sweden)

    Ristić Mihailo

    2007-01-01

    Full Text Available The essential oil isolated from flowers of Arnica montana and A chamissonis grown on Tara mountain and neighbourhood of Užice was analyzed. Three samples of A. montana and three of A. chamissonis were tested. The oil was isolated by distillation in a Clevenger type apparatus and analyzed by gas chromatography. The content of the oil was lower than 0.1% (up to 0.08% in all the samples. Among about hundred recorded constituents, 84 were identified and quantified. Sum of contents of identified components ranged between 96.1 and 98.8%. The most abundant constituents of the A. montana oil were p-caryophyllene (31.5-34.6%, germacrene D (12.5-16.3%, trans-a-ionone (3.9-4.3% and decanal (2.7-5.3%, while, in the case of A. chamissonis these were germacrene D (18.0-38.3%, a-pinene (6.6-19.1%, p-cymene (2.9-9.0% and P-caryophyllene (2.7-4.7%. Along with detail chemical analysis of essential oil of these two commercially important herbal drugs it should be noticed that gas chromatographic technique can be used for differentiation of A. montana and A. chamissonis.

  1. Measurement of Dam Deformations: Case Study of Obruk Dam (Turkey)

    Science.gov (United States)

    Gulal, V. Engin; Alkan, R. Metin; Alkan, M. Nurullah; İlci, Veli; Ozulu, I. Murat; Tombus, F. Engin; Kose, Zafer; Aladogan, Kayhan; Sahin, Murat; Yavasoglu, Hakan; Oku, Guldane

    2016-04-01

    In the literature, there is information regarding the first deformation and displacement measurements in dams that were conducted in 1920s Switzerland. Todays, deformation measurements in the dams have gained very different functions with improvements in both measurement equipment and evaluation of measurements. Deformation measurements and analysis are among the main topics studied by scientists who take interest in the engineering measurement sciences. The Working group of Deformation Measurements and Analysis, which was established under the International Federation of Surveyors (FIG), carries out its studies and activities with regard to this subject. At the end of the 1970s, the subject of the determination of fixed points in the deformation monitoring network was one of the main subjects extensively studied. Many theories arose from this inquiry, as different institutes came to differing conclusions. In 1978, a special commission with representatives of universities has been established within the FIG 6.1 working group; this commission worked on the issue of determining a general approach to geometric deformation analysis. The results gleaned from the commission were discussed at symposiums organized by the FIG. In accordance with these studies, scientists interested in the subject have begun to work on models that investigate cause and effect relations between the effects that cause deformation and deformation. As of the scientist who interest with the issue focused on different deformation methods, another special commission was established within the FIG engineering measurements commission in order to classify deformation models and study terminology. After studying this material for a long time, the official commission report was published in 2001. In this prepared report, studies have been carried out by considering the FIG Engineering Surveying Commission's report entitled, 'MODELS AND TERMINOLOGY FOR THE ANALYSIS OF GEODETIC MONITORING OBSERVATIONS

  2. Study on dynamic anti-sliding stability of a high gravity dam considering complex dam foundation

    OpenAIRE

    Deng-hong CHEN; Cheng-bin DU

    2011-01-01

    There existed some limitations when analyzing the anti-sliding seismic stability of dam-foundation system by traditional pseudo-static method and response spectrum method. The dynamic strength reduction method was used to study on the deep anti-sliding stability of a high gravity dam considering complex dam foundation under strong earthquake-induced ground action. The static analysis was firstly carried out by reducing the shear strength parameters of the dam foundation’s rock mass with equal...

  3. 78 FR 60271 - Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer of...

    Science.gov (United States)

    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...

  4. DAM IMPACTS ON AND RESTORATION OF AN ALLUVIAL RIVER - RIO GRANDE, NEW MEXICO

    Institute of Scientific and Technical Information of China (English)

    Gigi RICHARD; Pierre JULIEN

    2003-01-01

    The impact of construction of dams and reservoirs on alluvial rivers extends both upstream and downstream of the dam. Downstream of dams, both the water and sediment supplies can be altered leading to adjustments in the river channel geometry and ensuing changes in riparian and aquatic habitats.The wealth of pre and post-regulation data on the Middle Rio Grande, New Mexico, provides an excellent case study of river regulation, channel adjustments, and restoration efforts. Cochiti Dam was constructed on the main stem of the Rio Grande in 1973 for flood control and sediment retention. Prior to dam construction, the Rio Grande was a wide, sandy braided river. Following dam construction, the downstream channel bed degraded and coarsened to gravel size, and the planform shifted to a more meandering pattern. Ecological implications of the geomorphic changes include detachment of the river from the floodplain, reduced recruitment of riparian cottonwoods, encroachment of non-native saltcedar and Russian olive into the floodplain, and degraded aquatic habitat for the Rio Grande silvery minnow.Recent restoration strategies include removal of non-native riparian vegetation, mechanical lowering of floodplain areas, and channel widening.

  5. Numerical modelling for stability of tailings dams

    OpenAIRE

    Auchar, Muhammad; Mattsson, Hans; Knutsson, Sven

    2013-01-01

    A tailings dam is a large embankment structure that is constructed to store the waste from the mining industry. Stability problems may occur in a tailings dam due to factors such as quick rate of raising, internal erosion and liquefaction. The failure of a tailings dam may cause loss of human life and environmental degradation. Tailings Dams must not only be stable during the time the tailings storage facility is in operation, but also long time after the mine is closed. In Sweden, the licens...

  6. Debris Flow Dam Formation in Southeast Tibet

    Institute of Scientific and Technical Information of China (English)

    CHENG Zunlan; WU Jishan; GENG Xueyong

    2005-01-01

    Glaciers with their deposits abound in the alpine areas of Southeast Tibet. Large debris flows occur frequently from these deposits and form dams that block streams. In this paper, 3 events of large debris flows reported in Peilong Valley located in Southeast Tibet, and which resulted 2 blocking dams resulted, are discussed in details, focusing on the major factors controlling dam formation. The results shows that the first surge group caused by snow and ice avalanches, ice-lake breaks, and large-scale landslides, with a high peak discharge and high velocity, and an abundance of boulders, are most likely to form blocking dams.

  7. Comprehensive evaluation methods for dam service status

    Institute of Scientific and Technical Information of China (English)

    WU ZhongRu; XU Bo; GU ChongShi; LI ZhanChao

    2012-01-01

    More than 87000 dams have been built in China,and about one third of them are risky projects.A number of high and ultra-high dams are being constructed in China's western region.The current dam construction practice tends to focus on socio-economic benefits and neglect the environment and ecology.Furthermore,periodic examinations are intended to ensure the structural safety of dams.This paper proposes a general evaluation principle for dam service.This principle stipulates that dam projects should have maximum socio-economic benefits and minimum negative effects on the environment and ecology.To satisfy the general principle of mutual harmony,socio-economic benefits,dam safety,environment,and ecology are analyzed,and the evaluation methods for dam service status are discussed.Then,a fusion algorithm of interlayer assessment is proposed on the basis of evidence theory and the fuzzy comprehensive analysis method.Finally,a comprehensive evaluation model is established.Example analysis shows that the proposed theories and methods can fulfill scientific assessment of the service status of dams.

  8. Mountain plover responses to plague in Montana.

    Science.gov (United States)

    Dinsmore, Stephen J; Smith, Mark D

    2010-01-01

    Plague is a bacterial (Yersinia pestis) disease that causes epizootic die-offs in black-tailed prairie dog (Cynomys ludovicianus) populations in the North American Great Plains. Through their grazing and burrowing, prairie dogs modify vegetation and landscape structure on their colonies in ways that affect other grassland species. Plague epizootics on prairie dog colonies can have indirect effects on species associated with colonies. The mountain plover (Charadrius montanus) preferentially nests on black-tailed prairie dog colonies and is thus negatively impacted by the loss of prairie dogs. We studied the effects of plague and colony spatial characteristics on the occupancy of 81 prairie dog colonies by nesting plovers in Phillips County, Montana, during a 13-year period (1995-2007). We used a robust design patch occupancy model to investigate how colony occupancy and extinction and colonization rates were affected by plague history, colony size, and colony shape. Here extinction and colonization rates refer to the probability that a colony loses/gains plovers in a subsequent nesting season, given that it had/lacked plovers in that breeding season. Colony occupancy was best explained by a model with no annual variation or plague effects. Colony extinction rates were driven by a combination of a quadratic of colony area, a 3-year plague response, and a measure of colony shape. Conversely, colonization rates were best explained by a model with a 4-year plague response. The estimated annual proportion of colonies occupied by plovers was 0.75 (95% confidence interval = 0.57-0.87). Estimated extinction probability ranged from a low of 0.07 (standard error [SE] = 0.02) in 2002 to a high of 0.25 (SE = 0.03) in 1995; colonization probability ranged from 0.24 (SE = 0.05) in 2006 to 0.35 (SE = 0.05) in 2000. Our results highlight how a bird that depends on prairie dogs for nesting habitat responds to plague history and other spatial characteristics of the colony. Ultimately

  9. Influence of dams on river-floodplain dynamics in the Elwha River, Washington

    Science.gov (United States)

    Kloehn, K.K.; Beechie, T.J.; Morley, S.A.; Coe, H.J.; Duda, J.J.

    2008-01-01

    The Elwha dam removal project presents an ideal opportunity to study how historic reduction and subsequent restoration of sediment supply alter river-floodplain dynamics in a large, forested river floodplain. We used remote sensing and onsite data collection to establish a historical record of floodplain dynamics and a baseline of current conditions. Analysis was based on four river reaches, three from the Elwha River and the fourth from the East Fork of the Quinault River. We found that the percentage of floodplain surfaces between 25 and 75 years old decreased and the percentage of surfaces >75 years increased in reaches below the Elwha dams. We also found that particle size decreased as downstream distance from dams increased. This trend was evident in both mainstem and side channels. Previous studies have found that removal of the two Elwha dams will initially release fine sediment stored in the reservoirs, then in subsequent decades gravel bed load supply will increase and gradually return to natural levels, aggrading river beds up to 1 m in some areas. We predict the release of fine sediments will initially create bi-modal grain size distributions in reaches downstream of the dams, and eventual recovery of natural sediment supply will significantly increase lateral channel migration and erosion of floodplain surfaces, gradually shifting floodplain age distributions towards younger age classes.

  10. Suicide Report: A Health Risk Behavior Comparison of Montana High School Students Based on Attempted Suicide. 2011 Montana Youth Risk Behavior Survey

    Science.gov (United States)

    Montana Office of Public Instruction, 2013

    2013-01-01

    The Montana Youth Risk Behavior Survey (YRBS) is administered by the Montana Office of Public Instruction every two years to students in grades 7 through 12. The purpose of the survey is to help monitor the prevalence of behaviors that not only influence youth health, but also put youth at risk for the most significant health and social problems…

  11. Smokers Report: A Health Risk Behavior Comparison of Montana High School Students Based on Current Smoking. 2011 Montana Youth Risk Behavior Survey

    Science.gov (United States)

    Montana Office of Public Instruction, 2013

    2013-01-01

    The Montana Youth Risk Behavior Survey (YRBS) is administered by the Montana Office of Public Instruction every two years to students in grades 7 through 12. The purpose of the survey is to help monitor the prevalence of behaviors that not only influence youth health, but also put youth at risk for the most significant health and social problems…

  12. Sports Team Participation: A Risk Behavior Comparison of Montana High School Students Based on Sports Team Participation. 2011 Montana Youth Risk Behavior Survey

    Science.gov (United States)

    Montana Office of Public Instruction, 2012

    2012-01-01

    The Montana Youth Risk Behavior Survey (YRBS) is administered by the Montana Office of Public Instruction every two years to students in grades 7 through 12. The purpose of the survey is to help monitor the prevalence of behaviors that not only influence youth health, but also put youth at risk for the most significant health and social problems…

  13. Students with Special Needs: A Health Risk Behavior Comparison of Montana High School Students Based on Special Education Assistance. 2011 Montana Youth Risk Behavior Survey

    Science.gov (United States)

    Montana Office of Public Instruction, 2012

    2012-01-01

    The Montana Youth Risk Behavior Survey (YRBS) is administered by the Montana Office of Public Instruction every two years to students in grades 7 through 12. The purpose of the survey is to help monitor the prevalence of behaviors that not only influence youth health, but also put youth at risk for the most significant health and social problems…

  14. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; Annual Progress Report, April 2007 - March 2008.

    Energy Technology Data Exchange (ETDEWEB)

    Mallette, Christine [Oregon Department of Fish and Wildlife

    2009-07-28

    We report on our progress from April 2007 through March 2008 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), Columbia River Inter-Tribal Fish Commission (CRITFC; Report C), and Montana State University (MSU; Report D). This is a multi-year study with many objectives requiring more than one year to complete; therefore, findings from a given year may be part of more significant findings yet to be reported.

  15. Safety Aspects of Sustainable Storage Dams and Earthquake Safety of Existing Dams

    Directory of Open Access Journals (Sweden)

    Martin Wieland

    2016-09-01

    Full Text Available The basic element in any sustainable dam project is safety, which includes the following safety elements: ① structural safety, ② dam safety monitoring, ③ operational safety and maintenance, and ④ emergency planning. Long-term safety primarily includes the analysis of all hazards affecting the project; that is, hazards from the natural environment, hazards from the man-made environment, and project-specific and site-specific hazards. The special features of the seismic safety of dams are discussed. Large dams were the first structures to be systematically designed against earthquakes, starting in the 1930s. However, the seismic safety of older dams is unknown, as most were designed using seismic design criteria and methods of dynamic analysis that are considered obsolete today. Therefore, we need to reevaluate the seismic safety of existing dams based on current state-of-the-art practices and rehabilitate deficient dams. For large dams, a site-specific seismic hazard analysis is usually recommended. Today, large dams and the safety-relevant elements used for controlling the reservoir after a strong earthquake must be able to withstand the ground motions of a safety evaluation earthquake. The ground motion parameters can be determined either by a probabilistic or a deterministic seismic hazard analysis. During strong earthquakes, inelastic deformations may occur in a dam; therefore, the seismic analysis has to be carried out in the time domain. Furthermore, earthquakes create multiple seismic hazards for dams such as ground shaking, fault movements, mass movements, and others. The ground motions needed by the dam engineer are not real earthquake ground motions but models of the ground motion, which allow the safe design of dams. It must also be kept in mind that dam safety evaluations must be carried out several times during the long life of large storage dams. These features are discussed in this paper.

  16. Mechanical effects of excavation rebound of arch dam bedrock and better concreting time of dam body

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In high ground stress zone, rebound deformation of excavation of arch dam bedrock has a significant impact on the structural behavior, design and construction of arch dam. Based on the analysis of mechanical effects of excavation rebound, with both stress and deformation as two constraint conditions and deformation modulus as a controlling condition, the method to determine a better concreting time of dam body was put forward. All of these play an important guiding role in the excavation of dam bedrock and the construction of dam body.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hillson, Todd; Lind, Sharon; Price, William (Washington Department of Fish and Wildlife, Olympia, WA)

    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.

  18. Adaptability to geological faulted foundation of Hardfill dam

    Institute of Scientific and Technical Information of China (English)

    Kun XIONG; Yunlong HE; Yunfeng PENG

    2008-01-01

    Hardfill dam is a new type of dam which has the advantages of low stress level and even stress distri-bution in a dam body, resulting in low demands to foun-dations. Based on 2D linear elastic and elasto-plastic calculations of gravity dam and Hardfill dam using finite element method (FEM), the stress distribution in a dam body and anti-sliding stabilization is analyzed on the geo-logical faulted foundations with weak weathered rock and soft interlayers. It is concluded that Hardfill dams have better adaptability to geological faulted foundations than gravity dams and is more secure and economically sound.

  19. Vulnerability of aged concrete gravity dams

    Energy Technology Data Exchange (ETDEWEB)

    Gogoi, I. [Assam Engineering Institute, Guwahati (India). Dept. of Civil Engineering; Maity, D. [Indian Institute of Technology, Guwahati (India). Dept. of Civil Engineering

    2004-07-01

    This paper presented an analysis procedure to predict the effects of aging on the behavior of concrete gravity dams. A time dependent isotropic damage index was determined, presenting the performance of the dam with increasing age. Results revealed that the degradation process is dependent on the design life of the structure. The influence of damage along the dam height was greater than damage observed along its width. In order to consider the time dependent degradation of concrete owing to environmental factors and mechanical loading, an algorithm was presented in order to forecast the behavior of existing dams and to assess the necessity of retrofitting or decommissioning. It was concluded that dam behavior during seismic excitation is influenced by the effects of both the dam reservoir system and initial earthquake damage. With increasing age, dam displacement increases, but hydrodynamic pressures and stresses exerted by reservoirs decrease. It was recommended that more accurate behavior could be determined if further research into the coupled effect of foundation-dam-reservoir interaction with material non-linearity was considered. 15 refs.,15 figs.

  20. Upgrading of Boundary Dam spillway

    Energy Technology Data Exchange (ETDEWEB)

    McPhail, Gordon; MacMillan, Dave; Smith, Bert [KGS Group, Winnipeg, (Canada); Lacelle, Justin [SaskPower, Regina, (Canada)

    2010-07-01

    An initial dam safety review was performed in 2005 and identified a number of concerns; the most critical were insufficient spillway capacity and deficiencies in the condition of the existing spillways. This paper described the challenges faced by the upgrading operation on the 50 year old Boundary Dam spillway started in 2008. SaskPower retained the KGS Group to increase the design spillway capacity to 1200 m3/s and remedy observed defects. The construction project involved maintaining the reservoir at full supply level while the 20m long spillway chute and stilling basin below were completely replaced. The difficulties came from the need to complete each year's construction such that the spillway could potentially pass spring flood flows. This paper showed that the upgrade measures selected for implementation were developed through close dialogue between the owner and the designer, with valuable input provided by a panel of external experts as well as from contractors participating in the design process.

  1. VOLATILE COMPOUNDS OF WATER-ETHANOLIC EXTRACT OF SATUREJA MONTANA L.

    Directory of Open Access Journals (Sweden)

    A. E. Paliy

    2014-01-01

    Full Text Available We have studied a composition and content of volatile compounds of Satureja montana L. extract. It was established that concentration of volatile compounds in water-ethanol extract of S. montana amounted to 325 mg/100g. The principal component of the extract is carvacrol. It was shown that the extract of Satureja montana represents high biological value

  2. Restoring Environmental Flows by Modifying Dam Operations

    Directory of Open Access Journals (Sweden)

    Gregory A. Thomas

    2007-06-01

    Full Text Available The construction of new dams has become one of the most controversial issues in global efforts to alleviate poverty, improve human health, and strengthen regional economies. Unfortunately, this controversy has overshadowed the tremendous opportunity that exists for modifying the operations of existing dams to recover many of the environmental and social benefits of healthy ecosystems that have been compromised by present modes of dam operation. The potential benefits of dam "re-operation" include recovery of fish, shellfish, and other wildlife populations valued both commercially and recreationally, including estuarine species; reactivation of the flood storage and water purification benefits that occur when floods are allowed to flow into floodplain forests and wetlands; regaining some semblance of the naturally dynamic balance between river erosion and sedimentation that shapes physical habitat complexity, and arresting problems associated with geomorphic imbalances; cultural and spiritual uses of rivers; and many other socially valued products and services. This paper describes an assessment framework that can be used to evaluate the benefits that might be restored through dam re-operation. Assessing the potential benefits of dam re-operation begins by characterizing the dam's effects on the river flow regime, and formulating hypotheses about the ecological and social benefits that might be restored by releasing water from the dam in a manner that more closely resembles natural flow patterns. These hypotheses can be tested by implementing a re-operation plan, tracking the response of the ecosystem, and continually refining dam operations through adaptive management. The paper highlights a number of land and water management strategies useful in implementing a dam re-operation plan, with reference to a variety of management contexts ranging from individual dams to cascades of dams along a river to regional energy grids. Because many of the

  3. Coalbed Methane Extraction and Soil Suitability Concerns in the Powder River Basin, Montana and Wyoming

    Science.gov (United States)

    ,

    2006-01-01

    The Powder River Basin is located in northeastern Wyoming and southeastern Montana. It is an area of approximately 55,000 square kilometers. Extraction of methane gas from the coal seams that underlie the Powder River Basin began in Wyoming in the late 1980s and in Montana in the late 1990s. About 100-200 barrels of co-produced water per day are being extracted from each active well in the Powder River Basin, which comes to over 1.5 million barrels of water per day for all the active coalbed methane wells in the Basin. Lab testing indicates that Powder River Basin co-produced water is potable but is high in sodium and other salts, especially in the western and northern parts of the Powder River Basin. Common water management strategies include discharge of co-produced water into drainages, stock ponds, evaporation ponds, or infiltration ponds; treatment to remove sodium; or application of the water directly on the land surface via irrigation equipment or atomizers. Problems may arise because much of the Powder River Basin contains soils with high amounts of swelling clays. As part of the USGS Rocky Mountain Geographic Science Center's hyperspectral research program, researchers are investigating whether hyperspectral remote sensing data can be beneficial in locating areas of swelling clays. Using detailed hyperspectral data collected over parts of the Powder River Basin and applying our knowledge of how the clays of interest reflect energy, we will attempt to identify and map areas of swelling clays. If successful, such information will be useful to resource and land managers.

  4. Research progress on dam-break floods

    KAUST Repository

    Wu, Jiansong

    2011-08-01

    Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors\\' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.

  5. Do we need construct more dams?

    Science.gov (United States)

    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.

  6. Baxter v. Montana, libertarianism, and end-of-life: the ripe time for a paradigm shift.

    Science.gov (United States)

    Ruble, James H

    2010-09-01

    Baxter v. Montana (2009 WL 5155363 [Mont. 2009]) is a recent decision from the Montana Supreme Court that provides new legal insight into the societal issue of aid in dying. This case involves interests of persons with terminal illness, medical practitioners, law enforcement, legislative and judicial bodies, as well as the citizens of Montana. A summary judgment ruling at the Montana district court level was based almost entirely on a constitutional fundamental rights analysis. In contrast, the Montana Supreme Court affirming decision was based almost entirely on a statutory rights analysis. Both rulings from the Montana courts support the position that licensed prescribers in Montana who provide aid in dying assistance to terminally ill patients have some immunity from criminal prosecution. Each side in the case argued what they believed to be the intents and purposes of the people of Montana. Baxter v. Montana illustrates different methods to determine the will of the people concerning aid in dying and public policy. This case very subtly suggests a paradigm shift may be occurring in aid in dying policy.

  7. Seismic failure modes and seismic safety of Hardfill dam

    Institute of Scientific and Technical Information of China (English)

    Kun XIONG; Yong-hong WENG; Yun-long HE

    2013-01-01

    Based on microscopic damage theory and the finite element method, and using the Weibull distribution to characterize the random distribution of the mechanical properties of materials, the seismic response of a typical Hardfill dam was analyzed through numerical simulation during the earthquakes with intensities of 8 degrees and even greater. The seismic failure modes and failure mechanism of the dam were explored as well. Numerical results show that the Hardfill dam remains at a low stress level and undamaged or slightly damaged during an earthquake with an intensity of 8 degrees. During overload earthquakes, tensile cracks occur at the dam surfaces and extend to inside the dam body, and the upstream dam body experiences more serious damage than the downstream dam body. Therefore, under the seismic conditions, the failure pattern of the Hardfill dam is the tensile fracture of the upstream regions and the dam toe. Compared with traditional gravity dams, Hardfill dams have better seismic performance and greater seismic safety.

  8. Analysis on dam seepage and dam slope stability calculation in Renzhuang Reservoir%任庄水库大坝渗流及坝坡稳定计算分析

    Institute of Scientific and Technical Information of China (English)

    高超

    2016-01-01

    任庄水库防洪任务艰巨,大坝的安全至关重要。现状土坝坝体密实度不高且不均匀,内部存在多处软弱带,其坝坡稳定计算较为复杂。本文主要介绍了该土坝的渗流及坝坡稳定计算情况,并对计算参数选取及计算结果进行了合理性分析,最后判定该坝体不安全,水库属病险库,应尽快进行除险加固。%Renzhuang Reservoir has hard flood control task.Whether the dam is safe or not is very important.Current earth dam degree of density is low and uneven.There are many weak belts in the dam.The dam stability calculation is more complicated.In the paper,dam seepage and dam slope stability calculation condition are mainly introduced.The rationality of calculation parameter selection and calculation results is analyzed.Finally,it is determined that the dam body is not safe,the reservoir is risky.Risks should be removed for reinforcement as soon as possible.

  9. Mitigation for the Construction and Operation of Libby Dam, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Dunnigan, James L.; Marotz, Brian L.; DeShazer, Jay (Montana Department of Fish, Wildlife and Parks, Libby, MT)

    2003-06-01

    Libby Reservoir was created under an International Columbia River Treaty between the United States and Canada for cooperative water development of the Columbia River Basin (Columbia River Treaty 1964). Libby Reservoir inundated 109 stream miles of the mainstem Kootenai River in the United States and Canada, and 40 miles of tributary streams in the U.S. that provided habitat for spawning, juvenile rearing, and migratory passage (Figure 1). The authorized purpose of the dam is to provide power (91.5%), flood control (8.3%), and navigation and other benefits (0.2%; Storm et al. 1982). The Pacific Northwest Power Act of 1980 recognized possible conflicts stemming from hydroelectric projects in the northwest and directed Bonneville Power Administration to ''protect, mitigate, and enhance fish and wildlife to the extent affected by the development and operation of any hydroelectric project of the Columbia River and its tributaries...'' (4(h)(10)(A)). Under the Act, the Northwest Power Planning Council was created and recommendations for a comprehensive fish and wildlife program were solicited from the region's federal, state, and tribal fish and wildlife agencies. Among Montana's recommendations was the proposal that research be initiated to quantify acceptable seasonal minimum pool elevations to maintain or enhance the existing fisheries (Graham et al. 1982). Research to determine how operations of Libby Dam affect the reservoir and river fishery and to suggest ways to lessen these effects began in May, 1983. The framework for the Libby Reservoir Model (LRMOD) was completed in 1989. Development of Integrated Rule Curves (IRCs) for Libby Dam operation was completed in 1996 (Marotz et al. 1996). The Libby Reservoir Model and the IRCs continue to be refined (Marotz et al 1999). Initiation of mitigation projects such as lake rehabilitation and stream restoration began in 1996. The primary focus of the Libby Mitigation project now is to

  10. Mitigation for the Construction and Operation of Libby Dam, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Dunnigan, James; DeShazer, Jay; Garrow, Larry (Montana Department of Fish, Wildlife and Parks, Libby, MT)

    2004-06-01

    ''Mitigation for the Construction and Operation of Libby Dam'' is part of the Northwest Power and Conservation Council's (NPCC) resident fish and wildlife program. The program was mandated by the Northwest Planning Act of 1980, and is responsible for mitigating for damages to fish and wildlife caused by hydroelectric development in the Columbia River Basin. The objective of Phase I of the project (1983 through 1987) was to maintain or enhance the Libby Reservoir fishery by quantifying seasonal water levels and developing ecologically sound operational guidelines. The objective of Phase II of the project (1988 through 1996) was to determine the biological effects of reservoir operations combined with biotic changes associated with an aging reservoir. The objectives of Phase III of the project (1996 through present) are to implement habitat enhancement measures to mitigate for dam effects, to provide data for implementation of operational strategies that benefit resident fish, monitor reservoir and river conditions, and monitor mitigation projects for effectiveness. This project completes urgent and high priority mitigation actions as directed by the Kootenai Subbasin Plan. Montana FWP uses a combination of diverse techniques to collect a variety of physical and biological data within the Kootenai River Basin. These data serve several purposes including: the development and refinement of models used in management of water resources and operation of Libby Dam; investigations into the limiting factors of native fish populations, gathering basic life history information, tracking trends in endangered, threatened species, and the assessment of restoration or management activities intended to restore native fishes and their habitats.

  11. Mitigation for the Construction and Operation of Libby Dam, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Dunnigan, James; DeShazer, Jay; Garrow, Larry (Montana Department of Fish, Wildlife and Parks, Libby, MT)

    2005-06-01

    ''Mitigation for the Construction and Operation of Libby Dam'' is part of the Northwest Power and Conservation Council's (NPCC) resident fish and wildlife program. The program was mandated by the Northwest Planning Act of 1980, and is responsible for mitigating damages to fish and wildlife caused by hydroelectric development in the Columbia River Basin. The objective of Phase I of the project (1983 through 1987) was to maintain or enhance the Libby Reservoir fishery by quantifying seasonal water levels and developing ecologically sound operational guidelines. The objective of Phase II of the project (1988 through 1996) was to determine the biological effects of reservoir operations combined with biotic changes associated with an aging reservoir. The objectives of Phase III of the project (1996 through present) are to implement habitat enhancement measures to mitigate for dam effects, to provide data for implementation of operational strategies that benefit resident fish, monitor reservoir and river conditions, and monitor mitigation projects for effectiveness. This project completes urgent and high priority mitigation actions as directed by the Kootenai Subbasin Plan. Montana Fish, Wildlife & Parks (MFWP) uses a combination of techniques to collect physical and biological data within the Kootenai River Basin. These data serve several purposes including: the development and refinement of models used in management of water resources and operation of Libby Dam; investigations into the limiting factors of native fish populations, gathering basic life history information, tracking trends in endangered and threatened species, and the assessment of restoration or management activities designed to restore native fishes and their habitats.

  12. Montana Organization for Research in Energy (MORE) Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Bromenshenk, Jerry

    1999-12-31

    MORE is a consortium of educational, governmental, and industrial partners in cooperation with the state's Tribal colleges. Formed in 1994, the objectives are to develop and promote energy-related research and education in the state of Montana and the Northwestern region. Specifically, they set out to: (1) promote collaboration and cooperation among Montana's Colleges and Universities; (2) maximize use of existing personnel and resources; (3) foster partnerships with industries, state agencies, and tribal nations; and (4) enhance energy research and training. The 1st Implementation Grant consisted of Management and Coordination, Human Outreach, and two Research Clusters Petroleum Reservoir Characterization and Wind Energy. Overall, they consider this program to have been highly successful. That conclusion was mirrored by the DOE site reviewers, and by invitations from Dr. Matesh Varma, the DOE/EPSCoR National Program Director, to present their programs and outcomes as models for other states the National DOE/EPSCoR meetings.

  13. Seismic Analysis of Morrow Point Dam

    Energy Technology Data Exchange (ETDEWEB)

    Noble, C R

    2002-04-01

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

  14. Wind-Driven Ecological Flow Regimes Downstream from Hydropower Dams

    Science.gov (United States)

    Kern, J.; Characklis, G. W.

    2012-12-01

    challenge, the following study was designed to investigate the potential for wind power integration to alter riparian flow regimes below hydroelectric dams. A hydrological model of a three-dam cascade in the Roanoke River basin (Virginia, USA) is interfaced with a simulated electricity market (i.e. a unit commitment problem) representing the Dominion Zone of PJM Interconnection. Incorporating forecasts of electricity demand, hydro capacity and wind availability, a mixed-integer optimization program minimizes the system cost of meeting hourly demand and reserve requirements by means of a diverse generation portfolio (e.g. nuclear, fossil, hydro, and biomass). A secondary 'balancing' energy market is executed if real-time wind generation is less than the day-ahead forecast, calling upon reserved generation resources to meet the supply shortfall. Hydropower release schedules are determined across a range of wind development scenarios (varying wind's fraction of total installed generating capacity, as well as its geographical source region). Flow regimes for each wind development scenario are compared against both historical and simulated flows under current operations (negligible wind power), as well as simulated natural flows (dam removal), in terms of ecologically relevant flow metrics. Results quantify the ability of wind power development to alter within-week stream flows downstream from hydropower dams.

  15. Bioactivity and phytochemical characterization of Arenaria montana L.

    OpenAIRE

    Pereira, Eliana; Barros, Lillian; Calhelha, Ricardo C.; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Isabel C. F. R. Ferreira

    2014-01-01

    The bioactivity (antioxidant and cytotoxic activities) of the aqueous and methanolic extracts of Arenaria montana L., a plant commonly used in Portuguese folk medicine, was evaluated and compared. Furthermore, the phytochemical composition was determined regarding hydrophilic (sugars, organic acids and phenolic compounds) and lipophilic (fatty acids and tocopherols) compounds, in order to valorize this plant material as a functional food/nutraceutical. Fructose, oxalic acid, methyl-luteolin 2...

  16. Hair Removal

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Hair Removal KidsHealth > For Teens > Hair Removal A A A ... recommend an electrologist with the proper credentials. Laser Hair Removal How It Works: A laser is directed through ...

  17. Hair Removal

    Science.gov (United States)

    ... Surgery? Choosing the Right Sport for You Shyness Hair Removal KidsHealth > For Teens > Hair Removal Print A ... you need any of them? Different Types of Hair Before removing hair, it helps to know about ...

  18. 76 FR 71355 - United States et al. v. Blue Cross and Blue Shield of Montana, Inc. et al.; Proposed Final...

    Science.gov (United States)

    2011-11-17

    ... affordable prices can attract businesses and jobs to a state or region, and higher health-insurance prices.... *Attorney of Record. FOR PLAINTIFF STATE OF MONTANA: Steve Bullock, Attorney General of Montana. James...

  19. Cooperative Recovery Initiative: Bull Trout Restoration: Restoring Cold, Clean, Complex and Connected Habitat in the Blackfoot River Watershed of Montana.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Habitat degradation and the effects of climate change are the biggest threats to bull trout in the Blackfoot River watershed of Montana. Montana Fish, Wildlife &...

  20. TYPOLOGY OF LARGE DAMS. A REVIEW

    Directory of Open Access Journals (Sweden)

    Gheorghe ROMANESCU

    2015-06-01

    Full Text Available The dams represent hydrotechnical constructions meant to ensure a judicious use of water resources. The international literature is extremely rich in data regarding the large dams on Earth. In this context, a hierarchy of the main dams is attempted and the role they play in the economic development of the regions they were built in is underlined. The largest dams are built on the big rivers in Asia, North America, South America and Africa. The reservoirs have multiple roles: electricity production, drinking or industrial water supply, irrigations, recreation, etc. High costs and land fragility do not allow the construction of dams in the places most affected by drought or flood. This is why they are usually built in mountainous areas, at great distance from the populated centres. On the Romanian territory, there are 246 large dams, built in the hydrographical basins of Siret, Olt, Arges, Somes, etc. The largest rivers on Earth, by discharge, (Amazon and Zair do not also include the largest dams because the landform and the type of flow have not allowed such constructions.

  1. Nonlinear Seismic Analysis of Morrow Point Dam

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Ririe Dam Release Test Assessment

    Science.gov (United States)

    2013-06-01

    72 Lyme Road Hanover, NH 03755-1290 Stephen Hall and Jeremy Giovando US Army Engineer District, Walla Walla 201 North Third Avenue Walla Walla...11/2013 at 0330 2/12/2013 at 1410 10120114 95th St. (1) 10120115 55th St. (2) 2/11/2013 at 1010 2/12/2013 at 2120 10120111 55th St. (1) 9737377...Ririe Dam 2/10/2013 at 1440 0 hr 64,700 N 95th E 2/12/2013 at 1410 47 hr 30 min 0.32 0.32 33,020 55th St. Bridge 2/12/2013 at 2120 54 hr 40 min

  3. The Feasibility of Using an Ultrasonic Fish Tracking System in the Tailrace of Lower Granite Dam in 2002

    Energy Technology Data Exchange (ETDEWEB)

    Faber, Derrek M.; Weiland, Mark A.; Carlson, Thomas J.; Cash, Kenneth; Zimmerman, Shon A.

    2003-09-10

    This report describes a study conducted by PNNL in Spring 2002 at Lower Granite Dam on the Snake River for the US Army Corps of Engineers Portland District. Our goal was to determine the feasibility of using ultrasonic fish tracking in the untested environment of a hydroelectric dam tailrace. If fish tracking were determined to be feasible, we would track the movement of juvenile hatchery chinook (Oncorhynchus tshawytscha), juvenile hatchery steelhead (O. mykiss), and juvenile wild steelhead (O. mykiss) and relate their movement to dam operations. The majority of fish to be tracked were released as a part of a separate study conducted by the Biological Resources Division of the U.S. Geological Survey (BRD), which was investigating the movement of juvenile salmon in the forebay of Lower Granite Dam in relation to Removable Spillway Weir (RSW) testing. The two studies took place consecutively from April 14 to June 7, 2002.

  4. Massive accumulation of highly polluted sedimentary deposits by river damming

    Energy Technology Data Exchange (ETDEWEB)

    Palanques, Albert, E-mail: albertp@icm.csic.es [Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003 (Spain); Grimalt, Joan [Institute of Environmental Assessment and Water Research (CSIC), Jordi Girona, 18, Barcelona 08034 (Spain); Belzunces, Marc; Estrada, Ferran; Puig, Pere; Guillén, Jorge [Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003 (Spain)

    2014-11-01

    Uncontrolled dumping of anthropogenic waste in rivers regulated by dams has created contaminated deposits in reservoirs that have remained unidentified for decades. The Flix Reservoir is located in the Ebro River, the second largest river flowing into the NW Mediterranean, has been affected by residue dumping from a chlor-alkali electrochemical plant for decades. High-resolution seismic profiles, bathymetric data, surficial sediment samples and sediment cores were obtained in the Flix Reservoir to study the characteristics of the deposit accumulated by this dumping. These data were used to reconstruct the waste deposit history. Since the construction of the Flix Dam in 1948, more than 3.6 × 10{sup 5} t of industrial waste has accumulated in the reservoir generating a delta-like deposit formed by three sediment lobes of fine-grained material highly contaminated by Hg, Cd, Zn and Cr (max: 640, 26, 420 and 750 mg kg{sup −1}, respectively). This contamination was associated with the Hg that was used for the cathode in the electrochemical plant from 1949 and with the production of phosphorite derivatives from 1973. After the construction of two large dams only a few kilometres upstream during the 1960s, the solids discharged from the industrial complex became the main sediment source to the Flix Reservoir. The deposit has remained in the reservoir forming a delta that obstructs about 50% of the river water section. Its stability only depended on the flow retention by the Flix Dam. At present, this contaminated waste deposit is being removed from the water reservoir as it is a cause of concern for the environment and for human health downriver. - Highlights: • A delta-like anthropogenic deposit prograded into the reservoir behind the Flix dam. • More than 3.6 × 10{sup 5} t of anthropogenic waste was accumulated in less than 4 decades. • A waste deposit with extreme levels of Hg and Cd was trapped in the Flix Reservoir. • The main pollution was related to

  5. Preliminary assessment report for Fort William Henry Harrison, Montana Army National Guard, Helena, Montana. Installation Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    DuWaldt, J.; Meyer, T.

    1993-07-01

    This report presents the results of the preliminary assessment (PA) conducted by Argonne National Laboratory at a Montana Army National Guard (MTARNG) property near Helena, Montana. Preliminary assessments of federal facilities are being conducted to compile the information necessary for completing preremedial activities and to provide a basis for establishing corrective actions in response to releases of hazardous substances. The principal objective of the PA is to characterize the site accurately and determine the need for further action by examining site activities, quantities of hazardous substances present, and potential pathways by which contamination could affect public health and the environment. This PA satisfies, for the Fort William Henry Harrison property, requirements of the Department of Defense Installation Restoration Program.

  6. Stratigraphy and geologic history of the Montana group and equivalent rocks, Montana, Wyoming, and North and South Dakota

    Science.gov (United States)

    Gill, James R.; Cobban, William Aubrey

    1973-01-01

    During Late Cretaceous time a broad north-trending epicontinental sea covered much of the western interior of North America and extended from the Gulf of Mexico to the Arctic Ocean. The sea was bounded on the west by a narrow, unstable, and constantly rising cordillera which extended from Central America to Alaska and which separated the sea from Pacific oceanic waters. The east margin of the sea was bounded by the low-lying stable platform of the central part of the United States.Rocks of the type Montana Group in Montana and equivalent rocks in adjacent States, which consist of eastward-pointing wedges of shallow-water marine and nonmarine strata that enclose westward-pointing wedges of fine-grained marine strata, were deposited in and marginal to this sea. These rocks range in age from middle Santonian to early Maestrichtian and represent a time span of about 14 million years. Twenty-nine distinctive ammonite zones, each with a time span of about half a million years, characterize the marine strata.Persistent beds of bentonite in the transgressive part of the Claggett and Bearpaw Shales of Montana and equivalent rocks elsewhere represent periods of explosive volcanism and perhaps concurrent subsidence along the west shore in the vicinity of the Elkhorn Mountains and the Deer Creek volcanic fields in Montana. Seaward retreat of st randlines, marked by deposition of the Telegraph Creek, Eagle, Judith River, and Fox Hills Formations in Montana and the Mesaverde Formation in Wyoming, may be attributed to uplift in near-coastal areas and to an increase in volcaniclastic rocks delivered to the sea.Rates of transgression and regression determined for the Montana Group in central Montana reveal that the strandline movement was more rapid during times of transgression. The regression of the Telegraph Creek and Eagle strandlines averaged about 50 miles per million years compared with a rate of about 95 miles per million years for the advance of the strand-line during

  7. Impact of groundwater pumping vs. a large upstream dam on streamflows and temperature under varying climate

    Science.gov (United States)

    Risley, J. C.; Constantz, J. E.; Essaid, H.; Rounds, S. A.

    2009-12-01

    The relative impact of in-reach groundwater pumping versus a large upstream dam on streamflows and stream temperature was analyzed for humid, semiarid, and arid conditions with long dry seasons representing typical climate conditions where large dams are present, such as the western US or eastern Australia. A MODFLOW-2000 model, with the SFR1 stream-aquifer interaction module, the streamflow-routing package, and the grid-block rewetting option, was constructed to simulate monthly streamflows for 12 watershed scenarios described below. For each scenario streamflow output became input into a stream temperature simulation model. Stream temperatures were simulated using the CE-QUAL-W2 water quality model over a 110 km model grid, with the presence/absence of a dam at the top of the reach and pumping in the lower 60 km of the reach. Measured meteorological data from three representative locations in Oregon and California were used as model input to simulate the impact of varying climate conditions on streamflows and stream temperature. For each climate condition four hypothetical watershed scenarios were modeled: (1) natural [no dam or pumping], (2) large upstream dam present, (3) dam with in-reach pumping, and (4) no dam with pumping continued, resulting in 12 cases. Dam removal, in the presence or absence of pumping, created significant changes in streamflow resulting in significant changes in stream temperature throughout the year for all three climate conditions. From March to August, the presence of a dam caused monthly-mean stream temperatures to decrease on average by approximately 3.0, 2.5, and 2.0 oC for the humid, semiarid, and arid conditions, respectively; however, stream temperatures generally increased from September to February. Pumping caused stream temperatures to warm in summer and cool in winter by generally less than 0.5 oC. Though the impact of a large dam led to greater changes in stream temperature than the impact of pumping, ephemeral conditions

  8. Mechanical analysis of a gravity dam

    OpenAIRE

    Bergant, Urša

    2012-01-01

    In the first part of our work we will present the water supply project in Obala and backend Karst regions. The use of the river Reka and its tributary Suhorka is essential, since an amassment is going to be built on it. We decided to build the dam from rolled concrete, which is economically and environmentally better than a paved barrier or a classic concrete dam. The second part of our work includes tension and stability program calculations. The primary dimensions of the dam-taken from a te...

  9. Sustainability of dams-an evaluation approach

    Science.gov (United States)

    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

  10. Geophysics Methods in Electrometric Assessment of Dams

    Energy Technology Data Exchange (ETDEWEB)

    Davydov, V. A., E-mail: davydov-va@yandex.ru; Baidikov, S. V., E-mail: badikek@mail.ru; Gorshkov, V. Yu., E-mail: vitalaa@yandex.ru; Malikov, A. V., E-mail: alex.mal.1986@mail.ru [Russian Academy of Sciences, Geophysical Institute, Ural Branch (Russian Federation)

    2016-07-15

    The safety assessment of hydraulic structures is proposed to be conducted via geoelectric measurements, which are capable of assessing the health of earth dams in their natural bedding without intervention in their structure. Geoelectric measurements are shown as being capable of pinpointing hazardous parts of a dam, including areas of elevated seepage. Applications of such methods are shown for a number of mini-dams in the Sverdlovsk region. Aparameter (effective longitudinal conductivity) that may be used to monitor the safety of hydraulic structures is proposed. Quantitative estimates of this parameter are given in terms of the degree of safely.

  11. Model Development to Establish Integrated Operational Rule Curves for Hungry Horse and Libby Reservoirs - Montana, 1996 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Marotz, Brian; Althen, Craig; Gustafson, Daniel

    1996-01-01

    Hungry Horse and Libby dams have profoundly affected the aquatic ecosystems in two major tributaries of the Columbia River by altering habitat and water quality, and by imposing barriers to fish migration. In 1980, the U.S. Congress passed the Pacific Northwest Electric Power Planning and Conservation Act, designed in part to balance hydropower development with other natural resources in the Columbia System. The Act formed the Northwest Power Planning Council (Council) who developed a program to protect, mitigate and enhance fish and wildlife on the Columbia River and its tributaries. Pursuant to the Council`s Fish and Wildlife Program for the Columbia River System (1987), we constructed computer models to simulate the trophic dynamics of the reservoir biota as related to dam operation. Results were used to develop strategies to minimize impacts and enhance the reservoir and riverine fisheries, following program measures 903(a)(1-4) and 903(b)(1-5). Two FORTRAN simulation models were developed for Hungry Horse and Libby reservoirs located in northwestern Montana. The models were designed to generate accurate, short-term predictions specific to two reservoirs and are not directly applicable to other waters. The modeling strategy, however, is portable to other reservoir systems where sufficient data are available. Reservoir operation guidelines were developed to balance fisheries concerns in the headwaters with anadromous species recovery actions in the lower Columbia (Biological Rule Curves). These BRCs were then integrated with power production and flood control to reduce the economic impact of basin-wide fisheries recovery actions. These Integrated Rule Curves (IRCs) were developed simultaneously in the Columbia Basin System Operation Review (SOR), the Council`s phase IV amendment process and recovery actions associated with endangered Columbia Basin fish species.

  12. Analysis of Dam Influent Prototype%大坝渗流原型分析

    Institute of Scientific and Technical Information of China (English)

    董永立

    2011-01-01

    目前,全国性的"病险水库除险加固工程"前期工作正在紧张进行,而水库大坝坝体渗流的安全与否直接关系到整个大坝的安危.本文通过对荥阳市河王水库近20多年来的坝体、坝基测压管观测数据进行分析,得出大坝渗流安全不容乐观的结论,为其它病险水库的原始观测数据分析起到一个抛砖引玉的作用.%At present, the prework of the nationwide “danger removal and consolidation of sick and dangerous reservoirs project" is tightly operating.The dam body influent directly related to the safety of the whole dam. Through the analysis of Xingyang Hewang dam's main body, dam foundation piezometer tube data for the past two decades, the paper came to the conclusion that the dam influent safety problems were not optimistic which provided the reference for the original observation data analysis of other sick and dangerous dam.

  13. Past, Present, and Future Nutrient Quality of a Small Southeastern River: A Pre-Dam Assessment

    Directory of Open Access Journals (Sweden)

    Paul M. Stewart

    2013-07-01

    Full Text Available Riverine dams alter both the physical environment and water chemistry, thus affecting species assemblages within these environments. In the United States, dam construction is on the decline and there is a growing trend for dam removal. The Choctawhatchee, Pea, and Yellow Rivers Watershed Management Authority had initiated the permitting process for placing a reservoir dam on the Little Choctawhatchee River (LCR, a tributary to the Choctawhatchee River. The purpose of the proposed reservoir was water supply, and while the permit application has been suspended, history shows that this or related projects are likely to arise in the future. This study collected data on nutrient quality seasonally (four times from 12 sites in the LCR watershed from October 2007 to June 2008 in order to determine pre-dam conditions and to compare these data to historical and regional information. Historical and current nutrient concentrations were elevated throughout the watershed, in most cases above suggested criteria, and indicated that water quality of the river was and continues to be nutrient rich. A future reservoir at recent levels of water quality will likely be highly eutrophic, and anthropogenic influences will further stress this ecosystem and its water quality as the urban region expands.

  14. Reliablity analysis of gravity dams by response surface method

    Science.gov (United States)

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

    2013-04-01

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

  15. Discussion on construction and type selection of China high dams

    Institute of Scientific and Technical Information of China (English)

    Zhou Jianping; Yang Zeyan; Chen Guanfu

    2009-01-01

    At the beginning of 21st century, with the rapid and steady development of China economy, a lot of large scale hydropower projects with large dams from 200 m to 300 m high are being or to be buih. China dam constructions are reaching the level of 300 m high arch dam, 250 high CFRD (concrete face rockfill dam) and 200 m high RCC (roller compacted concrete) gravity dam. Due to the safety and the economy, the type selection for high dams has become the key issue during the argumentation for the hydropower projects, and further efforts are still needed in this aspect for high dams. After reviewing the high dam constructions in China and abroad, authors proposed some advices for the selection of dam types, and hope that it can provide some helpful information for the researches and the design of high dams.

  16. 76 FR 34799 - Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN

    Science.gov (United States)

    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...

  17. Determination of Seepage and Analysis of Earth Dams (Case Study: Karkheh Dam

    Directory of Open Access Journals (Sweden)

    A. Kamanbedast

    2011-01-01

    Full Text Available Because of the increasing trend of building dam throughout Iran; it is necessary to optimize dam buildings and operations. Dam or Hydropower industry has two types of buildings; normally: (1 Concrete dams (2 Embankment (earth dams. Generally, scientists and engineers use different methods to enhance safety and decrease any errors in calculation due to maintenance of water storage especially hydro structure of the dam. It is necessary to investigate the dam seepage control; commonly used by several methods. Seepage is one of the important issues for design, build and maintenance of dams awareness. Seepage problem and its rules helps scientist to select a suitable method of monitoring and solving such problem. These methods of analysis were carried out at civil and construction project. In this study, one of latest method of investigation of seepage behavior were analytically evaluated and compared with the actual rules. Based on determine results; several suggestions and optimization method were suggested. Therefore, an optimum method was scientifically selected. Besides that, flow condition of porous environment with application of numeric program was analyzed. Finally, all the results were lunched out from seep/w soft which is the most significant program about this matter; use of finite elements method is specified for saturated and unsaturated environment. Thus; leakage and seepage were defined as function of (time and position. Subsequently, the best seepage solutions for the dam constructing were scientifically identified.

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

    Science.gov (United States)

    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.

  19. Long-term dam safety monitoring of Punt dal Gall arch dam in Switzerland

    Institute of Scientific and Technical Information of China (English)

    M.WIELAND[1; G.F.KIRCHEN[2

    2012-01-01

    The 130 m high Punt dal Gall dam is located at the Swiss-Italian border in the South-eastern part of Switzerland and was completed in 1969.The dam is founded on highly folded and partially crushed dolomite and limestone formations.A grout curtain with an area of 120,000 m 2 was provided for controlling seepage.For the monitoring of the dam deformations five inverted pendulums were installed in the dam and three in the rock foundation of the right abutment outside of the dam.For a seasonal water level fluctuation in the reservoir of about 60 m the maximum amplitude of the radial displacement is 25 mm,which includes both the effects of the water load and temperature effects.Furthermore a comprehensive geodetic network was established,57 joint meters were installed and cracks in the crest gallery are monitored by crack meters.There are also thermometers,piezometers and rocmeters.Springs at the left and right banks of the dam are monitored and chemical analyses of the seepage water and springs are performed regularly.The dam is equipped with strong motion instruments and several near-field earthquakes have been recorded in the past.The paper describes the long-term safety monitoring of this 42 years old arch dam.A short description of the Swiss practice in dam safety monitoring and emergency planning is also given.

  20. Stroke Knowledge among Urban and Frontier First Responders and Emergency Medical Technicians in Montana

    Science.gov (United States)

    McNamara, Michael J.; Oser, Carrie; Gohdes, Dorothy; Fogle, Crystelle C.; Dietrich, Dennis W.; Burnett, Anne; Okon, Nicholas; Russell, Joseph A.; DeTienne, James; Harwell, Todd S.; Helgerson, Steven D.

    2008-01-01

    Purpose: To assess stroke knowledge and practice among frontier and urban emergency medical services (EMS) providers and to evaluate the need for additional prehospital stroke training opportunities in Montana. Methods: In 2006, a telephone survey of a representative sample of EMS providers was conducted in Montana. Respondents were stratified…

  1. 75 FR 4698 - Approval and Promulgation of Air Quality Implementation Plans; Montana; Revisions to the...

    Science.gov (United States)

    2010-01-29

    ... Administrative Rules of Montana. Revisions include minor editorial and grammatical changes, updates to the... minor editorial and grammatical changes, and update the citations and references to Federal laws and... Montana; they make minor editorial and grammatical changes, update the citations and references to...

  2. 75 FR 3993 - Approval and Promulgation of Air Quality Implementation Plans; Montana; Revisions to the...

    Science.gov (United States)

    2010-01-26

    ... the Administrative Rules of Montana; they include minor editorial and grammatical changes, updates to... minor editorial and grammatical changes, update the citations and references to federal and state laws... Rules of Montana; they make minor editorial and grammatical changes, update the citations and...

  3. Scheduling Recess before Lunch: Exploring the Benefits and Challenges in Montana Schools

    Science.gov (United States)

    Bark, Katie; Stenberg, Molly; Sutherland, Shelly; Hayes, Dayle

    2010-01-01

    Purpose/Objectives: The purpose of the "Montana Recess Before Lunch Survey" was to explore benefits, challenges, and factors associated with successful implementation of Recess Before Lunch (RBL), from the perspective of school principals. Methods: An online written questionnaire was distributed to all (N = 661) Montana elementary and…

  4. 75 FR 3489 - Notice of Public Meeting, Eastern Montana Resource Advisory Council Meeting

    Science.gov (United States)

    2010-01-21

    ... Montana Resource Advisory Council will be held on March 4, 2010, in Billings, MT. The meeting will start... in Montana. At these meetings, topics will include: Miles City and Billings Field Office manager..., 2010. M. Elaine Raper, District Manager. BILLING CODE 4310-DN-P...

  5. 2011 Montana Youth Risk Behavior Survey: American Indian Students on or near a Reservation

    Science.gov (United States)

    Montana Office of Public Instruction, 2011

    2011-01-01

    This report presents the 2011 Montana Youth Risk Behavior Survey high school student frequency distributions for American Indian students on or near a reservation. These frequency distributions are based upon surveys with 720 high school American Indian students on or near a reservation in Montana during February of 2011. Frequency distributions…

  6. Numerical Study of Two-Dimensional Viscous Flow over Dams

    Institute of Scientific and Technical Information of China (English)

    王利兵; 刘宇陆; 涂敏杰

    2003-01-01

    In this paper, the characteristics of two-dimensional viscous flow over two dams were numerically investigated. The results show that the behavior of the vortices is closely related to the space between two dams, water depth, Fr number and Reynolds number. In addition, the flow properties behind each dam are different, and the changes over two dams are more complex than over one dam. Finally, the relevant turbulent characteristics were analyzed.

  7. Research on Dam Simulation System Based on OpenGL

    Science.gov (United States)

    Li, Kairong; Wang, Juanni; Zuo, Kui; Yun, Jian

    Dam, not only has great ability to alleviate water shortages especially during the dry season which improve hydropower capacity, but also plays an imporant rule in the river ecosystem. Dam has significant effect in improving our water environment and protecting ecological system.This paper copes with the three-dimensional model of dams and discusses OpenGL modeling, lighting, material, model transformation, perspective transformation technologies to achieve visualization of the dam, and eventually we visualize the dam through concrete examples.

  8. Final Design Analysis : Lake Ladora Dam Repair

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is intended to present Rocky Mountain Arsenal with details concerning the remedial repair for Ladora Dam to meet the geotechnical concerns and hydrologic...

  9. Dams life; La vie des barrages

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This paper summarizes the conclusions of the annual inspections of French dams in operation (fissures, water oozing, concrete swelling etc..). Only the observations which require a special attention are reported. (J.S.)

  10. White Sturgeon Passage at The Dalles Dam

    Science.gov (United States)

    ,

    2008-01-01

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

  11. Risk assessment of tailings facility dam failure

    OpenAIRE

    Hadzi-Nikolova, Marija; Mirakovski, Dejan; Stefanova, Violeta

    2011-01-01

    This paper presents the consequences of tailings facility dam failure and therefore the needs for its risk assessment. Tailings are fine-grained wastes of the mining industry, output as slurries, due to mixing with water during mineral processing. Tailings dams vary a lot as it is affected by: tailings characteristics and mill output, site characteristics as: topography, hydrology, geology, groundwater, seismicity and available material and disposal methods. The talings which accumulat...

  12. Stability and performance of older dams

    Energy Technology Data Exchange (ETDEWEB)

    Dharmawardene, W.; Herbig, A.; Morrison, J. [Alberta Environment, AB (Canada); Chan, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2003-07-01

    There are 1300 licensed dams in Alberta. Most were designed and constructed between the late 1940s and the early 1960s. As a rule, compacted earthfill in preglacial and interglacial valleys in southern Alberta was used to construct all dams of moderate height. At these dam sites, the foundations are of valley infill alluvial soils underlain by weak rocks. The best prevailing engineering practices at the time were used to design these dams. It included drilling, soil testing prior to and during construction, and some stability analyses. Despite these measures, a number of the dams built on soft clays suffered significant deformations and cracking of the embankment during construction. A re-examination of the stability of some of the older dams in Alberta, owned by the provincial department of the Environment, was undertaken six years ago using currently accepted design practices. Allowance was made in the new analyses for the presence of shear zones and fissures in the foundation soils, as well as softening caused by wetting. Despite many years of apparently satisfactory service, Factors of Safety that were marginal or deficient were discovered at many dams. The authors presented case histories of three older dams (North and South McGregor, and North Ridge, all located in southern Alberta) for which the long term Factors of Safety were marginal under normal loading. A number of criteria, such as deformation, stress strain curves of foundation materials and the consequence of failure were taken into consideration in assessing and confirming the requirement for repair before any structural modifications were undertaken. Some of the repairs that were carried out were also briefly described. 12 refs., 4 tabs., 5 figs.

  13. [Special use permit for predator disease study associated with Montana black-footed ferret reintroduction, summer 1994 : Montana Department of Fish, Wildlife and Parks

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains a memorandum providing the Montana Black-Footed Ferret Working Group with information on the proposed predator collection that will happen...

  14. Walter Bouldin Dam failure and reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    Walter Bouldin is one of several hydroelectric developments of Alabama Power Company. On February 10, 1975, an earth embankment section of Walter Bouldin Dam was breached, causing total evacuation of the forebay reservoir and rendering the 225-MW power plant inoperable. The Federal Power Commission instituted an investigation of the dam failure, and a report on the investigation was published in February 1976. Subsequently, an evidentiary hearing was held before an administrative law judge who issued his initial decision on August 19, 1976. The Commission, on April 21, 1977, issued its Opinion No. 795 in which it adopted the initial decision with modifications and terminated the investigation of failure of Walter Bouldin Dam. Opinion No. 795 directs the staff of the Bureau of Power to prepare, for the future guidance of the Commission, a report on the deficiencies which were found in its investigation, together with advice as to how such deficiencies have been and should be remedied. Also, it directs the staff of the Bureau of Power to address certain general recommendations included in the initial decision. This report was prepared in response to that directive and summaries information on the dam failure and its investigation; the evidentiary hearing; the judge's recommendations, the reconstruction of the Bouldin Dam; and the evalution and status of the Federal Energy Regulatory Commission Dam safety program. (LCL)

  15. Reliability Analysis of High Rockfill Dam Stability

    Directory of Open Access Journals (Sweden)

    Ping Yi

    2015-01-01

    Full Text Available A program 3DSTAB combining slope stability analysis and reliability analysis is developed and validated. In this program, the limit equilibrium method is utilized to calculate safety factors of critical slip surfaces. The first-order reliability method is used to compute reliability indexes corresponding to critical probabilistic surfaces. When derivatives of the performance function are calculated by finite difference method, the previous iteration’s critical slip surface is saved and used. This sequential approximation strategy notably improves efficiency. Using this program, the stability reliability analyses of concrete faced rockfill dams and earth core rockfill dams with different heights and different slope ratios are performed. The results show that both safety factors and reliability indexes decrease as the dam’s slope increases at a constant height and as the dam’s height increases at a constant slope. They decrease dramatically as the dam height increases from 100 m to 200 m while they decrease slowly once the dam height exceeds 250 m, which deserves attention. Additionally, both safety factors and reliability indexes of the upstream slope of earth core rockfill dams are higher than that of the downstream slope. Thus, the downstream slope stability is the key failure mode for earth core rockfill dams.

  16. OVERVIEW OF DAM GULLY EROSION RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Traditionally gully erosion has been identified with the dissection of the landscape in agricultural settings but it is also recognized as a prevalent erosion feature in earthen dam auxiliary spillways and embankments. Flows through earthen spillways and over dam embankments, due to large rainfall events, have the potential to erode and breach the dam or spillway and result in catastrophic releases from the reservoir. The gully erosion process in an earthen spillway or on an embankment can be characterized by stages of initiation, development, and migration of a headcut. A headcut is defined as a near vertical drop at the upstream end of a gully. The rate of headcut migration is important in determining the breach potential of an earthen spillway and dam embankment. A research program is being conducted to examine the gully erosion processes of earthen dam auxiliary spillways and embankments. This paper describes: 1) the unique test facilities constructed to examine the dominant factors affecting the erosion of earthen spillways and embankments; 2) the observations of the erosion processes and results to date; and 3) the predictive relationships that have been developed for dam gully erosion research at the ARS Hydraulic Engineering Research Unit laboratory in Stillwater, OK.

  17. Distributional Impacts of Large Dams in China

    Science.gov (United States)

    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.

  18. Estimating flood inundation caused by dam failures

    Energy Technology Data Exchange (ETDEWEB)

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada). School of Engineering; Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)

    2006-01-15

    Recent advancements in modelling inundation due to dam failures have allowed easier and more illustrative analyses of potential outcomes. This paper described new model and mapping capabilities available using the HEC-RAS hydraulic model in concert with geographic information systems (GIS). The study area was the upper reaches of Canagagigue Creek and the Woolwich Dam near Elmira, Ontario. A hydraulic analysis of a hypothetical dam failure was developed based on the summer probable maximum flood (PMF) event. Limits extended from Woolwich Dam to downstream of the Town of Elmira. An incoming summer PMF hydrograph was set as the upstream boundary condition in the upstream model. Simulation parameters include simulation time-step; implicit weighting factor; water surface calculation tolerance; and output calculation interval. Peak flows were presented, as well as corresponding flood inundation results through the Town of Elmira. The hydraulic model results were exported to a GIS in order to develop inundation maps for emergency management planning. Results from post-processing included inundation maps for each of the simulated time-steps as well as an inundation animation for the duration of the dam breach. It was concluded that the modelling tools presented in the study can be applied to other dam safety assessment projects in order to develop effective and efficient emergency preparedness plans through public consultation and the establishment of impact zones. 1 tab., 2 figs.

  19. Powder River: data for cross-channel profiles at 22 sites in southeastern Montana from 1975 through 2012

    Science.gov (United States)

    Moody, John A.; Meade, Robert H.

    2013-01-01

    Powder River rises in the Bighorn Mountains of Wyoming and flows northward through a semi-arid landscape in Wyoming and Montana to the Yellowstone River. The river drains an area of 34,700 km2 and has an average discharge of about 500 million m3 y-1 or 16 m3 s-1. This view of the river looking northward, and hence downstream, was taken in October 2012 (see study reach map), about 20 km north of the Wyoming-Montana state line, about 4 km downstream from an operating gaging station at Moorhead, Montana (USGS station number 06324500), and about 80 river km upstream from a discontinued gaging station at Broadus, Montana (USGS station number 06324710). The river is emerging from a narrowly-confined reach, and the valley widens northward, bordered by hills of the coal-bearing Fort Union Formation. The river in this photo is at about bed-full flow (12 m3 s-1, Moody and others, 1999), and several riffles with disturbed water can be seen downstream between smooth glassy reaches of the river. A narrow band (~2-4 m wide) of reddish sedge (Scirpus spp.) grows just above the bed-full level along the edge of water with a wider band of mixed grasses (Agropyron repens, A. pauciflorum, Bromus inermis, Elymus canadenis, Spartina pectinata, and S. cynosoroids), willow (Salix exigua), tamarisk (Tamirix ramosissima) and small cottonwood seedlings and trees (Populus sargentii) on the flood plain. Three terrace levels have been identified along the river (Leopold and Miller, 1954; Moody and Meade, 2008). The first is the Lightning terrace with small cottonwood trees (seen here without leaves) adjacent to the floodplain in the right-center of the photo. The second is the Moorcroft terrace seen best forming the left bank and extending as a flat surface to the left (west) with a few large cottonwood trees still retaining their green leaves. The third is the colluvial Kaycee terrace that grades slowly upwards and meets the hills of the Fort Union Formation. It can be seen on the right side

  20. Use and application of inflatable dam seals in large concrete dams

    Energy Technology Data Exchange (ETDEWEB)

    Dickes, G. [Structural Preservation Systems Inc., Hanover, MD (United States)

    2001-10-01

    The successful installation of inflatable dam seals has been accomplished at several large concrete dams in the United States. This accomplishment was recently realized for the first time in Canada. The minimization of water intrusion caused by failed water stops in monolithic dams by a small diameter inflatable seal is one of the many uses for the device. Many problems encountered at large concrete dams are related to stress control of alkali-aggregate or alkali silica reaction (AAR, ASR), and the inflatable dam seal fits in as part of this control system. Many of the problems with concrete dams are due to AAR which causes concrete to expand, resulting in cracking of concrete and misalignment of equipment as two of the most important issues. A transverse vertical saw cut through the upper section of the concrete structure was one of the methods used to alleviate the stresses brought about by AAR. This method has been used on a number of occasions in both Canada and the United States. Once the saw cut is complete, from the upstream face to the downstream face, controlling the water flow in the kerf (13-19 millimeter) presents a major challenge. Successfully sealing failed water stops and saw cuts was accomplished by installing inflatable dam seals with vertical heights in excess of 38 meters. A specific seal must be designed in each case. Several elements of the composite construction seal meet the engineering requirements set forth by Dam Safety Officials and Engineers and Owners. Some case histories were presented, namely the Harry S. Truman Dam in Missouri, the Tennessee Valley Authority at several sites, the Hiwassee Dam in North Carolina, the Fontana Dam in Tennessee, and the Mactaquac Generating Station in New Brunswick. 10 refs., 11 figs.

  1. Some Biological Compounds, Radical Scavenging Capacities and Antimicrobial Activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana from Turkey

    Directory of Open Access Journals (Sweden)

    Erecevit, Pınar

    2011-03-01

    Full Text Available This study determined some biological compounds (fatty acid compositions, lipid-soluble vitamins, sterols, flavonoids, radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana. It was found that palmitic acid (C16:0; 8.54±0.13- 3.05±0.04%, oleic acid (C18:1 n9, 22.41±0.8-18.83±0.1% and α-linolenic acid (C18:3 n3;39.56±0.67-77.04±2.07% were the dominant fatty acids in both Nepeta italica L. and Sideritis montana L. subsp. montana. It was concluded that both Nepeta italica L. and Sideritis montana L. subsp. montana contained stigmasterol (630.07±1.81µg/g, 80.74±0.71µg/g, respectively and ergosterol (1.11±0.14µg/g, 161.32±0.63µg/g respectively as well as beta-sitosterol (2.93±0.03 µg/g. The present findings show that Nepeta italica L. contains morin (37.79±1.09μg/g, catechin (124.39±2.23µg/g, naringin (475.96±3.57µg/g and Sideritis montana L. subsp. montana contains morin (188.41±2.53µg/g, catechin (64.14±1.86μg/g, naringenin (38.34±1.78μg/g as major flavonoids. It was also determined that methanol extracts of Nepeta italica L. and Sideritis montana L. subsp. montana were most effective against DPPH radicals. The results of the present study show that the vitamins, flavonoids and fatty acid extracts in the seeds of N. italica L. and S. montana L. subsp. montana prevented the growth of the microorganisms used in the tests at different ratios.Este estudio ha determinado algunos compuestos biológicos (ácidos grasos, vitaminas liposolubles, esteroles y flavonoides, capacidad atrapadora de radicales libres, y actividades antimicrobianas de las semillas de Nepeta italica L. y Sideritis montana L. subsp. montana. Se encontró que el ácido palmítico (C16:0; 8.54±0.13-3.05±0.04%, ácido oleico (C18:1 n9, 22.41±0.8-18.83±0.1% y α-linolénico (C18:3 n 3;39.56±0.67-77.04±2.07% eran mayoritarios en ambas semillas de Nepeta italica L. y Sideritis

  2. The impact of damming on riverine fluxes to the ocean: A case study from Eastern Iceland.

    Science.gov (United States)

    Eiriksdottir, Eydis Salome; Oelkers, Eric H; Hardardottir, Jorunn; Gislason, Sigurdur Reynir

    2017-04-15

    Anthropogenic water management has extensively altered the world's river systems through impoundments and channel diversions to meet the human's need for water, energy and transportation. To illuminate the effect of such activities on the environment, this study describes the impact of the installation of the Kárahnjúkar Dam in Eastern Iceland on the transport of riverine dissolved- and particulate material to the ocean by the Jökulsá á Dal and the Lagarfljót rivers. This dam, completed in 2007, collects water into the 2.2 km(3) Hálslón reservoir and diverts water from the glacial Jökulsá á Dal river into the partially glaciated Lagarfljót lagoon via a headrace tunnel. The impact of the damming was evaluated by sampling water from both the Jökulsá á Dal and the Lagarfljót rivers over a 15 year period spanning from 1998 to 2013. The annual flux of most dissolved elements increased substantially due to the damming. The fluxes of dissolved Zn, Al, Co, Ti and Fe increased most by damming; these fluxes increased by 46-391%. These differences can be attributed to changed saturation states of common secondary minerals in the Jökulsá á Dal due to reduced discharge, increased residence time and dissolution of suspended material, and, to a lesser degree, reduced photosynthesis due to less transparency in the Lagarfljót lagoon. The removal of particulate material and thus decreasing adsorption potential in the Jökulsá á Dal is the likely reason for the Fe flux increase. In contrast, approximately 85% of the original riverine transported mass of particulate material is trapped by the dam; that which passes tends to be relatively fine grained, increasing the average specific surface area of that which continues to flow towards the ocean. Consequently, the particulate geometric surface area flux is decreased by only 50% due to the damming. The blooming of silica diatoms during the spring consumes dissolved silica from the coastal waters until it becomes

  3. Game model of safety monitoring for arch dam deformation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Arch dam deformation is comprehensively affected by water pressure,temperature,dam’s structural behavior and material properties as well as other factors.Among them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam’s structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore,resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model,where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height,and material property is embodied by the elastic modulus of dam.On the basis of analyzing the correlation between dam deformation and resistance factors,the game model of safety monitoring for arch dam deformation is put forward.

  4. The interplay of activists and dam developers : the case of Myanmar’s mega-dams

    NARCIS (Netherlands)

    Kirchherr, Julian; J. Charles, Katrina; Walton, Matthew J.

    2017-01-01

    Scholars investigating activism against large dam developments in Asia usually focus on those campaigning, but not on those the campaigns are aimed at–the dam developers. Yet the developers’ perspective is crucial to comprehensively understand the dynamics of social and environmental activism in

  5. Challenges of high dam construction to computational mechanics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chuhan

    2007-01-01

    The current situations and growing prospects of China's hydro-power development and high dam construction are reviewed,giving emphasis to key issues for safety evaluation of large dams and hydro-power plants,especially those associated with application of state-of-the-art computational mechanics.These include but are not limited to:stress and stability analysis of dam foundations under external loads;earthquake behavior of dam-foundation-reservoir systems,mechanical properties of mass concrete for dams,high velocity flow and energy dissipation for high dams,scientific and technical problems of hydro-power plants and underground structures,and newly developed types of dam-Roll Compacted Concrete (RCC) dams and Concrete Face Rock-fill (CFR)dams.Some examples demonstrating successful utilizations of computational mechanics in high dam engineering are given,including seismic nonlinear analysis for arch dam foundations,nonlinear fracture analysis of arch dams under reservoir loads,and failure analysis of arch dam-foundations.To make more use of the computational mechanics in high dam engineering,it is pointed out that much research including different computational methods,numerical models and solution schemes,and verifications through experimental tests and filed measurements is necessary in the future.

  6. Metal contamination and post-remediation recovery in the Boulder River watershed, Jefferson County, Montana

    Science.gov (United States)

    Unruh, Daniel M.; Church, Stanley E; Nimick, David A.; Fey, David L.

    2009-01-01

    The legacy of acid mine drainage and toxic trace metals left in streams by historical mining is being addressed by many important yet costly remediation efforts. Monitoring of environmental conditions frequently is not performed but is essential to evaluate remediation effectiveness, determine whether clean-up goals have been met, and assess which remediation strategies are most effective. Extensive pre- and post-remediation data for water and sediment quality for the Boulder River watershed in southwestern Montana provide an unusual opportunity to demonstrate the importance of monitoring. The most extensive restoration in the watershed occurred at the Comet mine on High Ore Creek and resulted in the most dramatic improvement in aquatic habitat. Removal of contaminated sediment and tailings, and stream-channel reconstruction reduced Cd and Zn concentrations in water such that fish are now present, and reduced metal concentrations in streambed sediment by a factor of c. 10, the largest improvement in the district. Waste removals at the Buckeye/Enterprise and Bullion mine sites produced limited or no improvement in water and sediment quality, and acidic drainage from mine adits continues to degrade stream aquatic habitat. Recontouring of hillslopes that had funnelled runoff into the workings of the Crystal mine substantially reduced metal concentrations in Uncle Sam Gulch, but did not eliminate all of the acidic adit drainage. Lead isotopic evidence suggests that the Crystal mine rather than the Comet mine is now the largest source of metals in streambed sediment of the Boulder River. The completed removal actions prevent additional contaminants from entering the stream, but it may take many years for erosional processes to diminish the effects of contaminated sediment already in streams. Although significant strides have been made, additional efforts to seal draining adits or treat the adit effluent at the Bullion and Crystal mines would need to be completed to

  7. 土石坝加固效果量化评价研究%Research on quantitative evaluation of earth and rockfill dam reinforcement effect

    Institute of Scientific and Technical Information of China (English)

    黄继艳

    2015-01-01

    In China,many reservoirs are provided with earth and rockfill dams.Dams commonly have disease conditions. Therefore,there are many methods for reinforcing earth and rockfill dam risk removal.There is no unified evaluation standard in earth dam risk removal and reinforcement effect.Quantitative evaluation on reinforcement effect still should be further studied.In the paper,quantitative evaluation system of earth and rockfill dam risk removal reinforcement effect is established,which is applied in Xiahetao Reservoir dam quantitative evaluation.The quantitative evaluation system of earth and rockfill dam risk removal reinforcement effect can provide guidance for earth and rockfill dam safety evaluation with important engineering significance.%我国许多水库都采用土石坝,大坝普遍存在病险情况,因此存在多种土石坝除险加固方法。土石坝除险加固效果尚无统一评价标准,如何对加固效果进行量化评价仍需进一步研究。本文在大坝安全评价的基础上,建立了土石坝除险加固效果量化评估体系,并在下河套水库大坝定量评价中加以应用。土石坝除险加固量化评估体系可为土石坝安全评价提供指导,具有重要的工程意义。

  8. 水库大坝劈裂灌浆的施工技术%On Construction Technique of Dam Fracturing Grouting

    Institute of Scientific and Technical Information of China (English)

    陈海港

    2012-01-01

    结合临汾市洹河水库大坝除险加固改造工程,详细介绍了大坝劈裂灌浆的施工方法及施工工艺。%In combination of the danger-removing and consolidating works for the dam of the Juhe Reservoir in Linfen city, the paper details the construction method and technique of dam fracturing grouting.

  9. Montana Integrated Carbon to Liquids (ICTL) Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Fiato, Rocco; Sharma, Ramesh; Allen, Mark; Peyton, Brent; Macur, Richard; Cameron, Jemima

    2013-09-30

    Integrated carbon-to-liquids technology (ICTL) incorporates three basic processes for the conversion of a wide range of feedstocks to distillate liquid fuels: (1) Direct Microcatalytic Coal Liquefaction (MCL) is coupled with biomass liquefaction via (2) Catalytic Hydrodeoxygenation and Isomerization (CHI) of fatty acid methyl esters (FAME) or trigylceride fatty acids (TGFA) to produce liquid fuels, with process derived (3) CO{sub 2} Capture and Utilization (CCU) via algae production and use in BioFertilizer for added terrestrial sequestration of CO{sub 2}, or as a feedstock for MCL and/or CHI. This novel approach enables synthetic fuels production while simultaneously meeting EISA 2007 Section 526 targets, minimizing land use and water consumption, and providing cost competitive fuels at current day petroleum prices. ICTL was demonstrated with Montana Crow sub-bituminous coal in MCL pilot scale operations at the Energy and Environmental Research Center at the University of North Dakota (EERC), with related pilot scale CHI studies conducted at the University of Pittsburgh Applied Research Center (PARC). Coal-Biomass to Liquid (CBTL) Fuel samples were evaluated at the US Air Force Research Labs (AFRL) in Dayton and greenhouse tests of algae based BioFertilizer conducted at Montana State University (MSU). Econometric modeling studies were also conducted on the use of algae based BioFertilizer in a wheat-camelina crop rotation cycle. We find that the combined operation is not only able to help boost crop yields, but also to provide added crop yields and associated profits from TGFA (from crop production) for use an ICTL plant feedstock. This program demonstrated the overall viability of ICTL in pilot scale operations. Related work on the Life Cycle Assessment (LCA) of a Montana project indicated that CCU could be employed very effectively to reduce the overall carbon footprint of the MCL/CHI process. Plans are currently being made to conduct larger-scale process

  10. Helenalin Acetate in in vitro Propagated Plants of Arnica montana.

    Science.gov (United States)

    Malarz, J; Stojakowska, A; Dohnal, B; Kisiel, W

    1993-02-01

    Propagated "IN VITRO" shoots and plantlets of ARNICA MONTANA L. (Asteraceae) have been shown to produce sesquiterpene lactones, i.e. helenalin and 11,13-dihydrohelenalin esters. The compounds were detected in green organs only; roots of the plantlets contained no sesquiterpene lactones. The helenalin acetate content in leaves of the plantlets (0.073% dry wt) was 4-times higher than in proliferated shoots (0.016% dry wt). The best rate of shoot multiplication was achieved on MS medium, supplemented with NAA 0.5mg/l and Kn 2.5 mg/l (formation of 22 shoots within 8 weeks).

  11. Immunologically active polysaccharides of Arnica montana cell cultures.

    Science.gov (United States)

    Puhlmann, J; Zenk, M H; Wagner, H

    1991-01-01

    From the nutrition medium of Arnica montana cell cultures two homogeneous polysaccharides, an acidic arabino-3,6-galactan-protein with mean Mr of 100,000 and a neutral fucogalactoxyloglucan with mean Mr of 22,500 have been isolated by DEAE-Sepharose CL-6B and Sephacryl S-400 column chromatography. Their structures were elucidated mainly by methylation analysis, partial acidic and enzymatic hydrolysis and 13C NMR spectroscopy. The fucogalactoxyloglucan shows a pronounced enhancement of phagocytosis in vivo. The arabino-3,6-galactan-protein displays a strong anticomplementary effect and stimulates macrophages to excrete the tumour necrosis factor (TNF alpha).

  12. Flavonoid Glycosides from Arnica montana and Arnica chamissonis.

    Science.gov (United States)

    Merfort, I; Wendisch, D

    1987-10-01

    Five flavonoid glycosides were identified from flowers of ARNICA MONTANA, four from A. CHAMISSONIS subsp. FOLIOSA var. INCANA. The structures were established on the basis of total acid hydrolysis and spectral data (UV, (1)H-NMR, (13)C-NMR, MS) as hispidulin 7- O-beta-glucoside, isorhamnetin 3- O-beta-glucoside, 3- O-beta- D-glucopyranosides of spinacetin, 6-methoxykaempferol and patuletin and querectin 3- O-(6''- O-acetyl)-beta- D-glucopyranoside. The latter compound can serve as distinctive marker between these two ARNICA species. The (1)H-NMR spectra in CD (3)OD are discussed.

  13. Avian use of Norris Hill Wind Resource Area, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Harmata, A.; Podruzny, K.; Zelenak, J. [Montana State Univ., Bozeman, MT (United States). Biology Dept.

    1998-07-01

    This document presents results of a study of avian use and mortality in and near a proposed wind resource area in southwestern Montana. Data collected in autumn 1995 through summer 1996 represented preconstruction condition; it was compiled, analyzed, and presented in a format such that comparison with post-construction data would be possible. The primary emphasis of the study was recording avian migration in and near the wind resource area using state-of-the-art marine surveillance radar. Avian use and mortality were investigated during the breeding season by employing traditional avian sampling methods, radiotelemetry, radar, and direct visual observation. 61 figs., 34 tabs.

  14. Tick Removal

    Science.gov (United States)

    ... ticks Tickborne diseases abroad Borrelia miyamotoi Borrelia mayonii Tick Removal Recommend on Facebook Tweet Share Compartir If ... a tick quite effectively. How to remove a tick Use fine-tipped tweezers to grasp the tick ...

  15. Hard choices in assessing survival past dams — a comparison of single- and paired-release strategies

    Science.gov (United States)

    Zydlewski, Joseph; Stich, Daniel S.; Sigourney, Douglas B.

    2017-01-01

    Mark–recapture models are widely used to estimate survival of salmon smolts migrating past dams. Paired releases have been used to improve estimate accuracy by removing components of mortality not attributable to the dam. This method is accompanied by reduced precision because (i) sample size is reduced relative to a single, large release; and (ii) variance calculations inflate error. We modeled an idealized system with a single dam to assess trade-offs between accuracy and precision and compared methods using root mean squared error (RMSE). Simulations were run under predefined conditions (dam mortality, background mortality, detection probability, and sample size) to determine scenarios when the paired release was preferable to a single release. We demonstrate that a paired-release design provides a theoretical advantage over a single-release design only at large sample sizes and high probabilities of detection. At release numbers typical of many survival studies, paired release can result in overestimation of dam survival. Failures to meet model assumptions of a paired release may result in further overestimation of dam-related survival. Under most conditions, a single-release strategy was preferable.

  16. Postpartum behavioral profiles in Wistar rats following maternal separation - altered exploration and risk-assessment behavior in MS15 dams

    Directory of Open Access Journals (Sweden)

    Loudin Daoura

    2010-06-01

    Full Text Available The rodent maternal separation (MS model is frequently used to investigate the impact of early environmental factors on adult neurobiology and behavior. The majority of MS studies assess effects in the offspring and few address the consequences of repeated pup removal in the dam. Such studies are of interest since alterations detected in offspring subjected to MS may, at least in part, be mediated by variations in maternal behavior and the amount of maternal care provided by the dam. The aim of this study was to investigate how daily short (15 min; MS15 and prolonged (360 min; MS360 periods of MS affects the dam by examining postpartum behavioral profiles using the multivariate concentric square field™ (MCSF test. The dams were tested on postpartum days 24-25, i.e. just after the end of the separation period and weaning. The results reveal a lower exploratory drive and lower risk-assessment behavior in MS15 dams relative to MS360 or animal facility reared dams. The present results contrast some of the previously reported findings and provide new information about early post-weaning behavioral characteristics in a multivariate setting. Plausible explanations for the results are provided including a discussion how the present results fit into the maternal mediation hypothesis.

  17. Design and construction of Nemiscau-1 Dam, the first asphalt core rockfill dam in North America

    Energy Technology Data Exchange (ETDEWEB)

    Alicescu, V.; Tournier, J.P. [Hydro-Quebec, Montreal, PQ (Canada); Vannobel, P. [Societe d' Energie de la Baie James, Montreal, PQ (Canada)

    2008-07-01

    The concept of asphalt as a waterproofing medium inside embankment dams was originally developed in Germany in the 1960s. More than 100 asphalt core rockfill (ACRD) dams have been completed or are under construction. They all have a strong record without any seepage problems or required maintenance. After using the glacial till as waterproofing material for its embankment dams for more than 50 years, Hydro-Quebec is now looking to develop new dam concepts, mainly for the zones where natural waterproofing materials do not exist. In order to do so, the company has decided to design and construct the Nemiscau-1 Dam as a prototype ACRD. This paper presented the detailed design criteria, technical specifications as well as some information concerning the construction of the dam such as asphalt mix design. The given dam site, geology and materials is well suited for a dam with an asphalt core and the chosen core thickness of minimum 400 mm was found to be appropriate, given the small net water head. The main reservoir levels as well as the characteristics of the dam were also listed. Information on the general construction of the dam was provided. It was concluded that the longitudinal profile of the rock excavation and concrete plinth must be optimized, with an optimum balance between the rock excavation, the volume and shape of the concrete plinth and finally, the placement of the asphalt core with the manual method. Several combinations of these 3 elements must be analyzed at the design stage and the most cost effective one should be applied on site. 5 tabs., 7 figs.

  18. The future role of dams in the United States of America

    Science.gov (United States)

    Ho, Michelle; Lall, Upmanu; Allaire, Maura; Devineni, Naresh; Kwon, Hyun Han; Pal, Indrani; Raff, David; Wegner, David

    2017-02-01

    xml:id="wrcr22481-sec-1001" numbered="no">Storage and controlled distribution of water have been key elements of a human strategy to overcome the space and time variability of water, which have been marked by catastrophic droughts and floods throughout the course of civilization. In the United States, the peak of dam building occurred in the mid-20th century with knowledge limited to the scientific understanding and hydrologic records of the time. Ecological impacts were considered differently than current legislative and regulatory controls would potentially dictate. Additionally, future costs such as maintenance or removal beyond the economic design life were not fully considered. The converging risks associated with aging water storage infrastructure and uncertainty in climate in addition to the continuing need for water storage, flood protection, and hydropower result in a pressing need to address the state of dam infrastructure across the nation. Decisions regarding the future of dams in the United States may, in turn, influence regional water futures through groundwater outcomes, economic productivity, migration, and urban growth. We advocate for a comprehensive national water assessment and a formal analysis of the role dams play in our water future. We emphasize the urgent need for environmentally and economically sound strategies to integrate surface and groundwater storage infrastructure in local, regional, and national water planning considerations. A research agenda is proposed to assess dam failure impacts and the design, operation, and need for dams considering both paleo and future climate, utilization of groundwater resources, and the changing societal values toward the environment.

  19. Recent fault movement in Lake McDonald, Montana: Evidence from acoustic sub-bottom profiling

    Science.gov (United States)

    Dunbar, J. A.; Cronin, V. S.; Allen, P. M.; White, J. D.

    2011-12-01

    Lake McDonald is the largest of the 12 large lakes in Glacier National Park, Montana, formed in previously glaciated valleys and dammed by outwash and moraine deposits at their outlets. Lake McDonald is 15 km long, 1.6 km wide and trends northeast. The location of the lake was on the eastern edge of the Cordilleran Ice Sheet during the late Wisconsin Glaciation. Published maps indicate the lake basin is crossed by the northwest-striking Flathead and Nyack normal faults and two unnamed faults (Whipple, 1992, USGS Map I-1508-F). Recent seismicity in northwest Montana consists mostly of magnitude 3 to 4 earthquakes, one of which occurred between the Flathead and Nyack faults, northwest of the lake. Using 1 kHz Uniboom profiling of Lake McDonald, Mullins and others (1991, Arctic Alpine Res 23(3), 311-319) found 150 m of simply-stratified, undisturbed sediment fill within a V-shaped bedrock basin with steeply sloping sides. No evidence was found to suggest that the faults within the lake have been recently active. In this study, we collected 55 km of 24 kHz sub-bottom profiling data to more closely examine the upper 10 m of the sediment fill for evidence of recent fault motion. The upper 10 m of the fill consists of sub-meter thick, alternating layers of highly reflective and nearly acoustically transparent deposits, along with numerous chaotic mass-wasting deposits emanating from the adjacent sides of the basin. One of these mass-wasting deposits is 1.3 km wide, 5 m thick, and lies unburied on the modern lake floor. The trace of Flathead Fault, where it crosses the northeastern end of the lake, is marked by a precipitous, 125 m high, down-to-the-southwest escarpment. The base of the escarpment consists of a series of basinward-stepping terraces, the southwestern-most of which is onlapped by recent sediment. The onlapping sediments show no clear evidence of faulting next to the escarpment, but motion between the various terraces cannot be ruled out. The trace of Nyack

  20. EXPERIMENTAL INVESTIGATION OF THE FAILURE OF CASCADE LANDSLIDE DAMS

    Institute of Scientific and Technical Information of China (English)

    NIU Zhi-pan; XU Wei-lin; LI Nai-wen; XUE Yang; CHEN Hua-yong

    2012-01-01

    This paper preseuts results of model tests for the landslide dam failure of a single dam and cascade dams in a sloping channel.The dams were designed to be regular trapezoid with fine sand.A new measuring method named the labeled line locating method was used to digitalize the captured instantaneous pictures.Under two differem inflow discharges,the morphological evolution and the flow patterns during one dam failure and the failure of cascade dams were investigated.The results indicate that when the inflow discharge is large,the deformation pattern of the downstream dam is similar to that of the upstream dam,and both dams are characterized with the overtopping scour throughout the dam failure process.When the inflow discharge is small,the upstream dam is scoured mainly through a sluice slot formed by the longitudinal incision,and the downstream dam is characterized with the overtopping scour.The data set presented in this paper can be used for the validation of numerical models and provide a reference for the flood risk management of cascade landslide dams.

  1. Hydrogeologic data for the northern Rocky Mountains intermontane basins, Montana

    Science.gov (United States)

    Dutton, DeAnn M.; Lawlor, Sean M.; Briar, D.W.; Tresch, R.E.

    1995-01-01

    The U.S. Geological Survey began a Regional Aquifer- System Analysis of the Northern Rocky Mountains Intermontane Basins of western Montana and central and central and northern Idaho in 1990 to establish a regional framework of information for aquifers in 54 intermontane basins in an area of about 77,500 square miles. Selected hydrogeologic data have been used as part of this analysis to define the hydro- logic systems. Records of 1,376 wells completed in 31 of the 34 intermontane basins in the Montana part of the study area are tabulated in this report. Data consist of location, alttiude of land surface, date well constructed, geologic unit, depth of well, diameter of casing, type of finish, top of open interval, primary use of water, water level, date water level measured, discharge, specific capacity, source of discharge data, type of log available, date water-quality parameters measured, specific conductance, pH, and temperature. Hydrographs for selected wells also are included. Locations of wells and basins are shown on the accompanying plate.

  2. Chemical characteristics of the major thermal springs of Montana

    Energy Technology Data Exchange (ETDEWEB)

    Mariner, R.H.; Presser, T.S.; Evans, W.C.

    1976-07-01

    Twenty-one thermal springs in western Montana were sampled for chemical, isotope, and gas compositions. Most of the springs issue dilute to slightly saline sodium-bicarbonate waters of neutral to slightly alkaline pH. A few of the springs issue sodium-mixed anion waters of near neutral pH. Fluoride concentrations are high in most of the thermal waters, up to 18 miligrams per litre, while F/Cl ratios range from 3/1 in the dilute waters to 1/10 in the slightly saline waters. Most of the springs are theoretically in thermodynamic equilibrium with respect to calcite and fluorite. Nitrogen is the major gas escaping from most of the hot springs; however, Hunters Hot Springs issue principally methane. The deuterium content of the hot spring waters is typical of meteoric water in western Montana. Geothermal calculations based on silica concentrations and Na-K-Ca ratios indicate that most of the springs are associated with low temperature aquifers (less than 100/sup 0/C). Chalcedony may be controlling the silica concentrations in these low temperature aquifers even in ''granitic'' terranes.

  3. International small dam safety assurance policy benchmarks to avoid dam failure flood disasters in developing countries

    Science.gov (United States)

    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.

  4. Re-grouting of Maroon Dam foundation

    Energy Technology Data Exchange (ETDEWEB)

    Palassi, M. [Tehran Univ. (Iran, Islamic Republic of). Dept. of Civil Engineering; Sharghi, A. [JTMA Co., Tehran (Iran, Islamic Republic of)

    2003-07-01

    The Maroon dam, built on the Maroon River in the Khoozestan province (southwest) of Iran, has a height of 176 metres and a 1.2 billion cubic metre reservoir. It is one of the largest embankment dams in Iran. A number of unpredicted inflows of water into tunnels and other underground openings occurred during the first impoundment of the Maroon dam. Impoundment was halted and the reservoir was emptied to correct the problem. This paper reviews the measures that were implemented during the remediation process, and presented an evaluation of the effectiveness of the process. The foundation treatment involved placing concrete in the caverns, constructing a concrete lining, and extending the grout curtain. The grouting procedure was also described. The overall effectiveness of the concrete work and grouting resulted in a reduction in leakage from 8.5 cubic metres per second to a more acceptable 10 litres per second. 8 figs.

  5. Channel changes downstream from a dam

    Science.gov (United States)

    Hadley, R.F.; Emmett, W.W.

    1998-01-01

    A flood-control dam was completed during 1979 on Bear Creek, a small tributary stream to the South Platte River in the Denver, Colorado, area. Before and after dam closure, repetitive surveys between 1977 and 1992 at five cross sections downstream of the dam documented changes in channel morphology. During this 15-year period, channel width increased slightly, but channel depth increased by more than 40 percent. Within the study reach, stream gradient decreased and median bed material sizes coarsened from sand in the pools and fine gravel on the riffle to a median coarse gravel throughout the reach. The most striking visual change was from a sparse growth of streamside grasses to a dense growth of riparian woody vegetation.

  6. Design of tailing dam using red mud

    Science.gov (United States)

    Rout, Subrat; Sahoo, Tapaswini; Das, Sarat

    2013-06-01

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

  7. Riverbed-Sediment Mapping in the Edwards Dam Impoundment on the Kennebec River, Maine By Use of Geophysical Techniques

    Science.gov (United States)

    Dudley, Robert W.

    1999-01-01

    INTRODUCTION In July 1997, the Federal Energy Regulatory Commission (FERC) issued a Final Environmental Impact Statement recommending that the 162-year-old Edwards Dam on the Kennebec River in Augusta, Maine, be removed. The impoundment formed by Edwards Dam extends about 15 mi to the city of Waterville, near the confluence of the Sebasticook River with the Kennebec River. The impoundment has a surface area of 1,143 acres, a gross storage of approximately 740 million ft3, and a usable storage of about 184 million ft3 (Stone and Webster, 1995a). According to FERC, removal of the 917-ft-long, 24-ft-high timber crib and concrete structure would restore 15 mi of riverine habitat, improve passage of ocean-migrating fish species native to the Kennebec River, and result in substantial recreational enhancements (Federal Energy Regulatory Commission, 1997). Because the removal of Edwards Dam would change the hydraulic characteristics of the river in the present-day impoundment, the potential transport of erodible, fine-grained sediment currently in the impoundment is a concern. Of particular concern is the erosion and transport of this sediment to areas downstream from the dam, a process that could introduce possible bacterial and chemical contamination and could impede river navigation as a result of sediment deposition. In an effort to build upon available information on the composition of the riverbed, the U.S. Geological Survey (USGS), in cooperation with the Maine State Planning Office, classified riverbed sediment types and mapped their areal extents in the lower (southern) half of the Edwards Dam impoundment. This report describes the methods used to collect and analyze the data used to create a map of sediment types in the Edwards Dam impoundment. The map is included with this report. Data used to map riverbed sediment types were also used to estimate the volume of observed mud and mud-containing sediment in the study area.

  8. Study on dynamic anti-sliding stability of a high gravity dam considering complex dam foundation

    Directory of Open Access Journals (Sweden)

    Deng-hong CHEN

    2011-06-01

    Full Text Available There existed some limitations when analyzing the anti-sliding seismic stability of dam-foundation system by traditional pseudo-static method and response spectrum method. The dynamic strength reduction method was used to study on the deep anti-sliding stability of a high gravity dam considering complex dam foundation under strong earthquake-induced ground action. The static analysis was firstly carried out by reducing the shear strength parameters of the dam foundation’s rock mass with equal proportion. Then, the time-history seismic analysis was carried out based on the static analysis. It was proposed as one of dynamic instability criterions that the peak values of the dynamic displacements and plastic strain energy change suddenly with increasing strength reduction coefficient. The elasto-plastic behavior of the dam foundation was idealized using Drucker–Prager yield criterion based on associated flow rule assumption. Through the static, dynamic strength reduction analysis and dynamic linear elastic analysis of the overflow dam monolith of a high gravity dam, the results’ reliability of elastic-plastic time history analysis was confirmed. The results also showed that the rock mass strength of the high gravity dam foundation has higher strength reserve coefficient. The instability criterions of dynamic strength reduction method proposed were feasible. Although the static anti-slide analysis methods and standards of gravity dam based on the numerical methods are being discussed at present, the dynamic calculation method and instability criterions proposed in this paper would provide some meaningful suggestions for the dynamic analysis of the similar projects.

  9. Predicting Water Levels at Kainji Dam Using Artificial Neural Networks

    African Journals Online (AJOL)

    Predicting Water Levels at Kainji Dam Using Artificial Neural Networks. ... The aim of this study is to develop artificial neural network models for predicting water levels at Kainji Dam, which supplies water to Nigeria's largest ... Article Metrics.

  10. Inventory of Dams in the State of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Permitted dams in Iowa and associated attributes, as recorded by the Floodplain Section of the DNR. The dams regulated are those with the parameters listed below: a....

  11. National Inventory of Dams Coastal California Extract 2010

    Data.gov (United States)

    California Department of Resources — The National Inventory of Dams (NID) is a congressionally authorized database, which documents dams in the U.S. and its territories. The NID was most recently...

  12. Research review of the cement sand and gravel (CSG) dam

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The cement sand and gravel (CSG) dam is a new style of dam that owes the advantages both of the concrete faced rock-fill dam (CRFD) and roller compacted concrete (RCC) gravity dam,because of which it has attracted much attention of experts home and abroad.At present,some researches on physic-mechanical property of CSG material and work behavior of CSG dam have been done.This paper introduces the development and characteristics of CSG dam systematically,and summarizes the progress of the study on basic tests,constitutive relation of CSG material and numerical analysis of CSG dam,in addition,indicates research and application aspect of the dam.

  13. Computational Aspects of Dam Risk Analysis: Findings and Challenges

    Directory of Open Access Journals (Sweden)

    Ignacio Escuder-Bueno

    2016-09-01

    Full Text Available In recent years, risk analysis techniques have proved to be a useful tool to inform dam safety management. This paper summarizes the outcomes of three themes related to dam risk analysis discussed in the Benchmark Workshops organized by the International Commission on Large Dams Technical Committee on “Computational Aspects of Analysis and Design of Dams.” In the 2011 Benchmark Workshop, estimation of the probability of failure of a gravity dam for the sliding failure mode was discussed. Next, in 2013, the discussion focused on the computational challenges of the estimation of consequences in dam risk analysis. Finally, in 2015, the probability of sliding and overtopping in an embankment was analyzed. These Benchmark Workshops have allowed a complete review of numerical aspects for dam risk analysis, showing that risk analysis methods are a very useful tool to analyze the risk of dam systems, including downstream consequence assessments and the uncertainty of structural models.

  14. Harvesting river water through small dams promote positive environmental impact.

    Science.gov (United States)

    Agoramoorthy, Govindasamy; Chaudhary, Sunita; Chinnasamy, Pennan; Hsu, Minna J

    2016-11-01

    While deliberations relating to negative consequences of large dams on the environment continue to dominate world attention, positive benefits provided by small dams, also known as check dams, go unobserved. Besides, little is known about the potential of check dams in mitigating global warming impacts due to less data availability. Small dams are usually commissioned to private contractors who do not have clear mandate from their employers to post their work online for public scrutiny. As a result, statistics on the design, cost, and materials used to build check dams are not available in public domain. However, this review paper presents data for the first time on the often ignored potential of check dams mitigating climate-induced hydrological threats. We hope that the scientific analysis presented in this paper will promote further research on check dams worldwide to better comprehend their eco-friendly significance serving society.

  15. The Characterization of Chlorophyll-A and Microalgae Isolation Process of Wastewater Collected at Sembrong Dam

    Science.gov (United States)

    Wellson, R.; Othman, N.; Matias-Peralta, H. M.

    2016-07-01

    isolation are good biological indicator that indicate the pollution of Sembrong Dam. The pure culture is very important that it can be used for further studies with series of different tests to understand its properties and character for sustainability approach towards environmentally friendly as well as for microalgae removal formula.

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

    Science.gov (United States)

    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

  17. Lac Courte Oreilles Hydro Dam Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Jason [Lac Courte Oreilles, Hayward, WI (United States); Meyers, Amy [Kiser Hydro, LLC, Norway, MI (United States)

    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.

  18. Fluid Flow in Tundish Due to Different Type Arrangement of Weir and Dam

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Tundish is an important metallurgical reactor in the continuous casting process. In order to control the fluid flow in tundish and thus take full advantage of the residence time available for the removal of inclusions from molten steel, the effect of weir and dam on the fluid flow has been studied in a water model based on the characteristic number Froude and Reynold number similarity criteria. The residence time distribution curves of the flow were measured by SG800. The optimum arrangement of dam and weir and the nonstationary flow in tundish were discussed. The results show that the combination of weir and dam is benefit for the flow pattern in tundish, weir can prevent the upper recirculating flow, dam can cut off the bottom flow and turn to upwards, it is advantageous to separate the nonmetallic inclusions. Furthermore, it is important to exceed the critical depth of bath during exchange ladles, not only for the inclusion floatation but also for avoiding tundish slag drainage earlier.

  19. Research on Dam Perspective Based on Numerical Solution

    Institute of Scientific and Technical Information of China (English)

    WANGZi-ru; ZHOUHui-cheng; LIMing-qiu

    2005-01-01

    The numerical solution of dam toe line is solved based on the dam data and topographic map of dam located. The display of dam perspective is also realized by programming of using VC++ and OpenGL. The research results above provide the foundation of construction design, construction lofting and information inquiry, which avoids the drawbacks of only using blueprints to do the same work in the past. The method used is useful in practical engineering.

  20. Geophysical Investigation of Buried Slag at the Parrot Tailings Site, Butte, Montana

    Science.gov (United States)

    Ha, C. D. M.; Shepherd, K.; Mack, A.; Rutherford, B. S.; Speece, M. A.

    2016-12-01

    Butte, Montana, has served as an important mining district for more than 120 years. This area contains historic mine waste from decades of unregulated mining practices. In July 1881, the Parrot smelter in Butte started operations and was soon processing ore and producing copper. The Parrot smelter also had a concentrating plant that treated the ore prior to smelting. The Parrot smelter wastes (slag and tailings) were later covered with Berkeley Pit crushed quartz monzonite overburden. The slag is bricked because it was deposited hot and, as a consequence forms a laterally extensive, cohesive, hard body that is difficult to remove without blasting. With the mine waste being covered by unknown quantities of overburden and soil throughout the area, and core data being limited and expensive to retrieve, the only economical method of discovery is geophysics. Several geophysical techniques were used to determine the lateral boundaries and depth of the buried slag body. The geophysical methods used were seismic, gravity, electromagnetic induction, and magnetics. Not all of these geophysical surveys produced useful results due to the nature of the slag. For instance, electromagnetic induction could not distinguish between the slag and adjacent tailings; and, the microgravity profiles showed only a small gravitational field variation caused by the density contrast between slag and the surrounding tailings, sediment and granitic cover. On the other hand, the seismic surveys resulted in unexpected first arrival times that distinctly showed velocity variations due to the slag. In addition, the slag body produced a large magnetic response. Unpublished, proprietary well data allowed us to model the slag body from our magnetic data. This model was confirmed by projecting velocity tomograms, that we created using seismic diving waves, onto our magnetic models. Model results were combined to form a three-dimensional image of the slag body. These results will be used to help

  1. Major dams of the United States, Geographic NAD83, USGS (2006) [dams00x020_USGS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — This map layer portrays major dams of the United States, including Puerto Rico and the U.S. Virgin Islands. The map layer was created by extracting dams 50 feet or...

  2. 43 CFR 418.18 - Diversions at Derby Dam.

    Science.gov (United States)

    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...

  3. 25 CFR 173.16 - Reserved area, Coolidge Dam.

    Science.gov (United States)

    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....

  4. 21 CFR 872.6300 - Rubber dam and accessories.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  5. SEISMIC RESPONSE OF DAM WITH SOIL-STRUCTURE INTERACTION.

    Science.gov (United States)

    Bycroft, G.N.; Mork, P.N.

    1987-01-01

    An analytical solution to the response of a long trapezoidal-section dam on a foundation consisting of an elastic half-space and subjected to simulated earthquake motion is developed. An optimum seismic design is achieved when the cross section of the dam is triangular. The effect of soil structure interaction is to lower the strain occurring in the dam.

  6. Hungry Horse Dam Fisheries Mitigation; Kokanee Stocking and Monitoring in Flathead Lake, 1996 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carty, Daniel [Fish and Wildlife Service, Kalispell, MT (United States); Knoetek, W. Ladd [Montana Fish, Wildlife and Parks, Kalispell, MT (United States)] Hansen, Barry [Confederated Salish and Kootenai Tribes of the Flathead Nation, Pablo, MT (United States)

    1997-06-01

    Kokanee salmon Oncorhynchus nerka were introduced into Flathead Lake in 1916. The kokanee population declined in the 1960s and 1970s, and kokanee disappeared from Flathead Lake in the late 1980s. Their disappearance has been attributed to the long-term effects of the construction and operation of Hungry Horse and Kerr dams, excessive harvest by anglers, and changes in the lake food web induced by the introduction of opossum shrimp Mysis relicta. Attempts to reestablish kokanee in the Flathead Lake ecosystem between 1988 and 1991 were unsuccessful. In 1991, Montana Fish, Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribes (CSKT) wrote a mitigation plan to restore kokanee to Flathead Lake. In 1993, MFWP, CSKT, and the U.S. Fish and Wildlife Service wrote a mitigation implementation plan that initiated a 5-year test program to use hatchery-reared fish to reintroduce kokanee to the lake. Stocking hatchery-reared kokanee into Flathead Lake began in 1993; the 5-year {open_quotes}kokanee test{close_quotes} started in 1994 and is scheduled to continue through 1998. The annual stocking objective is 1 million yearling kokanee (6-8 in long). Criteria used to evaluate the success of the 5-year test are (1) 30% survival of kokanee 1 year after stocking, (2) yearling-to-adult survival of 10%, and (3) annual harvest of 50,000 kokanee ({ge} 11 in) and fishing effort {ge} 100,000 angler hours.

  7. Northwest Montana Wetland Management District Annual narrative report: Calendar year 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1988 calendar year. The report begins...

  8. Northwest Montana Wetland Management District: Annual narrative report: Calendar year 1977

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1977 calendar year. The report begins with an...

  9. Northwest Montana Wetland Management District: Annual narrative report: Calendar year 1978

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1978 calendar year. The report begins with an...

  10. MT—Impacts of Oil Exploration and Production to the Northeast Montana Wetland Management District

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Northeast Montana Wetland Management District provides habitat for numerous different species of breeding waterfowl and migrating shorebirds, including the...

  11. Montana Integrated Monitoring in Bird Conservation Regions: 2014 Field Implementation Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2014 the Avian Science Center (ASC) at the University of Montana (UM) participated in the Integrated Monitoring in Bird Conservation Regions (IMBCR) program for a...

  12. 75 FR 4036 - Approval and Promulgation of Air Quality Implementation Plans; Montana; Revisions to the...

    Science.gov (United States)

    2010-01-26

    ... Administrative Rules of Montana. Revisions include minor editorial and grammatical changes, updates to the citations and references to federal and state laws and regulations, other minor changes to conform...

  13. 40 CFR 272.1351 - Montana State-Administered Program: Final Authorization.

    Science.gov (United States)

    2010-07-01

    ... Annotated (MCA) 2005, Title 25, “Civil Procedure”: Chapter 20, “Rules of Civil Procedure”, Rule 24(a). (iii) Montana Code Annotated (MCA) 2005, Title 27, “Civil Liability, Remedies, and Limitations”: Chapter...

  14. Final report on biogeochemical cycling of selenium in Benton Lake, Montana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The biogeochemical cycling of selenium in Benton Lake National Wildlife Refuge, west-central Montana was very complicated. Selenium accumulation in sediment was a...

  15. Saline seep impacts on Hailstone and Halfbreed National Wildlife Refuges in south-central Montana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Elevated salt and selenium levels in groundwater and in saline seeps within the Lake Basin of northern Stillwater County, Montana have impacted water quality on...

  16. 77 FR 43046 - Lolo National Forest; Montana; Center Horse Landscape Restoration EIS

    Science.gov (United States)

    2012-07-23

    ... Forest Service Lolo National Forest; Montana; Center Horse Landscape Restoration EIS AGENCY: Forest.... ADDRESSES: Send written comments to: Center Horse Landscape Restoration Project Leader, USDA Forest Service..., Monday through Friday. SUPPLEMENTARY INFORMATION: Purpose and Need for Action The Center Horse...

  17. Northwest Montana Wetland Management District Annual narrative report: Calendar year 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1985 calendar year. The report begins...

  18. The Story of Story Mill-A Montana Community Working to Restore Wetlands

    Science.gov (United States)

    Story Mill, a 55-acre site on the outskirts of Bozeman, Montana, has undergone several transformations in recent history. The place is virtually a “mill of stories” with respect to land use, but originally it was a wetland.

  19. Northwest Montana Wetlands Management District Annual narrative report: Calendar year 1980

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines Refuge accomplishments during the 1980 calendar year. The report begins with...

  20. 75 FR 66718 - Helena National Forest; Montana; Blackfoot Travel Plan EIS

    Science.gov (United States)

    2010-10-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Forest Service Helena National Forest; Montana; Blackfoot Travel Plan EIS AGENCY: Forest Service, USDA... the existing motorized public access routes and prohibitions within the Blackfoot travel planning...

  1. Anti-inflammatory activity of Arnica montana 6cH: preclinical study in animals.

    Science.gov (United States)

    Macêdo, S B; Ferreira, L R; Perazzo, F F; Carvalho, J C

    2004-04-01

    The anti-inflammatory effect of Arnica montana 6cH was evaluated using acute and chronic inflammation models. In the acute, model, carrageenin-induced rat paw oedema, the group treated with Arnica montana 6cH showed 30% inhibition compared to control (P < 0.05). Treatment with Arnica 6cH, 30 min prior to carrageenin, did not produce any inhibition of the inflammatory process. In the chronic model, Nystatin-induced oedema, the group treated 3 days previously with Arnica montana 6cH had reduced inflammation 6 h after the inflammatory agent was applied (P < 0.05). When treatment was given 6 h after Nystatin treatment, there was no significant inhibitory effect. In a model based on histamine-induced increase of vascular permeability, pretreatment with Arnica montana 6cH blocked the action of histamine in increasing vascular permeability.

  2. 6-O-Isobutyryl-tetrahydrohelenalin from the flowers of Arnica montana.

    Science.gov (United States)

    Willuhn, G; Röttger, P M; Wendisch, D

    1984-02-01

    From the flowers of ARNICA MONTANA L., the helenanolides 6- O-isobutyryl-tetrahydrohelenalin and 2beta-ethoxy-6- O-isobutyryl-2,3-dihydrohelenalin were isolated and their structures established by spectroscopic methods.

  3. Wyodak-Anderson clinker in the Powder River Basin, Wyoming and Montana (prbclkg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This ArcView shapefile contains a polygon representation of the Wyodak-Anderson clinker in the Powder River Basin, Wyoming and Montana. This theme was created...

  4. Digital Geologic Map of Glacier National Park, Montana (NPS, GRD, GRE, GLAC)

    Data.gov (United States)

    National Park Service, Department of the Interior — The Digital Geologic Map of Glacier National Park, Montana is comprised of GIS data layers, two ancillary GIS tables, a Windows Help File with ancillary map text,...

  5. Northwest Montana Wetland Management District, Swan River National Wildlife Refuge: Annual narrative report: Calendar year 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1989 calendar year. The report begins...

  6. National Bison Range, Ninepipe, Pablo and Swan River NWR's, Northwest Montana Wetlands: 1976 [Narrative report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for National Bison Range, Ninepipe NWR, Pablo NWR, Swan River NWR, and Northwest Montana Wetlands outlines Refuge accomplishments during the...

  7. Northwest Montana Wetland Management District, Swan River National Wildlife Refuge: Annual narrative report: Calendar year 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1990 calendar year. The report begins...

  8. Northwest Montana Wetland Management District Annual narrative report: Calendar year 1987

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1987 calendar year. The report begins...

  9. Northwest Montana Wetland Management District, Swan River National Wildlife Refuge: Annual narrative report: Calendar year 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Northwest Montana Wetland Management District outlines District accomplishments during the 1991 calendar year. The report begins...

  10. Trace elements and organochlorines in sediments and fish from Missouri River reservoirs in Montana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Federal Energy Regulatory Commission (FERC) is currently reviewing the application submitted by the Montana Power Company (MPC) for relicensing their...

  11. Effectiveness and Safety of Arnica montana in Post-Surgical Setting, Pain and Inflammation.

    Science.gov (United States)

    Iannitti, Tommaso; Morales-Medina, Julio César; Bellavite, Paolo; Rottigni, Valentina; Palmieri, Beniamino

    2016-01-01

    Arnica montana has been widely used as a homeopathic remedy for the treatment of several inflammatory conditions in pain management and postoperative settings. This review gives an overview of the therapeutic use of Arnica montana in the above-mentioned fields also focusing on its mechanisms of action learned from animal models and in vitro studies. Arnica montana is more effective than placebo when used for the treatment of several conditions including post-traumatic and postoperative pain, edema, and ecchymosis. However, its dosages and preparations used have produced substantial differences in the clinical outcome. Cumulative evidence suggests that Arnica montana may represent a valid alternative to non-steroidal anti-inflammatory drugs, at least when treating some specific conditions.

  12. The expected collapse of a large dam Saddam Dam in Iraq; Un grand barrage a haut risque Saddam Dam en Irak

    Energy Technology Data Exchange (ETDEWEB)

    Mesny, M. [Conseil general du genie rural, des eaux et des forets, 75 - Paris (France)

    2004-07-01

    The Saddam dam is a very large dam in Iraq on the Tigris River, 80 kilometres upstream from the city of Mosul. It is a fill dam with a clayey silt core. The height of the dam is 120 meters and the capacity of the reservoir is 11 billions m3. But this dam has been built on foundations of gypsum that is a rock soluble in water. The impounding of the reservoir in 1986 has shown that, in spite of the grout curtain, substantial seepage has occurred (up to 1.4 m{sup 3}/s), as well as the dissolution of minerals from foundations (up to 80 tons per day). The substantial increase in permeability and seepage through the dam foundations results in a severe concern about the stability of the dam. The program of injection has been stopped in 1991, due to the circumstances. So there is a real risk that this dam would collapse through a quickly developing leak in the dike, resulting in the devastation of the rich agricultural valley of the Tigris River and in potential human losses at Mosul. A 10 to 20-meter high submersion wave would reach this town 3 to 4 hours after the collapse of the dam. An international action is urgently required to check the conditions of the dam and to propose remedial solutions, which may be a 120-meter deep concrete wall down to the calcareous floor existing below the soluble layers of the foundations. (author)

  13. Dams life. Dams in operation; La vie des barrages. Barrages en exploitation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This paper summarizes the conclusions of the annual inspections of French dams in operation (fissures, water oozing, concrete swelling etc..). Only the observations which require a special attention are reported. (J.S.)

  14. DAM-LAKEFRONT PLAZA: Revitalization of an Agriculture Reservoir Dam in Kashar-Tirana/Albania

    Directory of Open Access Journals (Sweden)

    Valbona Koçi

    2014-12-01

    Full Text Available The Dam-Lakefront Plaza in Kashar-Tirana/Albania is a research project that proposes not only the re-consideration and reinforcement of the artificial Reservoirs Dams built during Socialism in Albania, but envisions the maintenance of dams and revitalization of the lakeside area promoting the public-private collaboration. In addition, it envisions the generation of qualitative and lively public spaces in sub-urban areas as well. Admitting the artificial lakes as specific nodes of man-made infrastructure in the landscape, and consequently the dams (together with the drainage channels as important hydrotechnic elements of the flood protection infrastructure, this research intends to elaborate on one type of landscape infrastructure - the vertical screens, offering a mediation between the natural and built landscape.

  15. Evaluation of antioxidant and cytoprotective activities of Arnica montana L. and Artemisia absinthium L. ethanolic extracts

    Directory of Open Access Journals (Sweden)

    Craciunescu Oana

    2012-09-01

    Full Text Available Abstract Background Arnica montana L. and Artemisia absinthium L. (Asteraceae are medicinal plants native to temperate regions of Europe, including Romania, traditionally used for treatment of skin wounds, bruises and contusions. In the present study, A. montana and A. absinthium ethanolic extracts were evaluated for their chemical composition, antioxidant activity and protective effect against H2O2-induced oxidative stress in a mouse fibroblast-like NCTC cell line. Results A. absinthium extract showed a higher antioxidant capacity than A. montana extract as Trolox equivalent antioxidant capacity, Oxygen radical absorbance capacity and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity, in correlation with its flavonoids and phenolic acids content. Both plant extracts had significant effects on the growth of NCTC cells in the range of 10–100 mg/L A. montana and 10–500 mg/L A. absinthium. They also protected fibroblast cells against hydrogen peroxide-induced oxidative damage, at the same doses. The best protection was observed in cell pre-treatment with 10 mg/L A. montana and 10–300 mg/L A. absinthium, respectively, as determined by Neutral red and lactate dehydrogenase assays. In addition, cell pre-treatment with plant extracts, at these concentrations, prevented morphological changes induced by hydrogen peroxide. Flow-cytometry analysis showed that pre-treatment with A. montana and A. absinthium extracts restored the proportion of cells in each phase of the cell cycle. Conclusions A. montana and A. absinthium extracts, rich in flavonoids and phenolic acids, showed a good antioxidant activity and cytoprotective effect against oxidative damage in fibroblast-like cells. These results provide scientific support for the traditional use of A. montana and A. absinthium in treatment of skin disorders.

  16. TEMPORARY REMOVAL

    DEFF Research Database (Denmark)

    Calkins, Hugh; Hindricks, Gerhard; Cappato, Riccardo

    2017-01-01

    The publisher regrets that this article has been temporarily removed. A replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. The full Elsevier Policy on Article Withdrawal can be found at https://www.e...

  17. 7 CFR 1724.55 - Dam safety.

    Science.gov (United States)

    2010-01-01

    ... result from encountering unanticipated or unusual conditions during construction. (5) The independent review of construction shall include: (i) Foundation preparation and treatment. When the foundation has... construction. The reviewer must have demonstrated experience in the design and construction of dams of...

  18. Aquifer performance under the Mactaquac Dam

    Energy Technology Data Exchange (ETDEWEB)

    Tawil, A.H. [Acres International, Niagara Falls, ON (Canada); Harriman, F.B. [New Brunswick Power, Fredericton, NB (Canada)

    2001-10-01

    The highest dam in the whole of the Maritimes and New Brunswick in particular is the Mactaquac Dam, with a height of 58 m above the foundation. It forms an integral part of the Mactaquac Hydroelectric Development and the construction of the dam was completed in 1967. Composed of a central core of clay till and external shells of rockfill, it is a zoned embankment. The high artesian pressure rising 6 m above the Saint John River dominates, and the foundation under the dam is composed of a stratum of stiff glacial till underlain with a thick, water bearing aquifer. The aquifer needed to be depressurized during the construction phase and in the long term, and special measures were required to accomplish this. Measurements obtained over a period exceeding 30 years were used to describe the performance of the aquifer, which is discussed in this presentation. A continuous reduction in the yield from the six permanent relief wells in the aquifer was indicated by the instrumentation data. The outflow from the wells diminished by two-thirds over the thirty-four years since first filling the reservoir. The piezometric pressure in the aquifer remained constant over the same period. The sparse results of a two-hour pump test had formed the basis for the design decision not to install a costly foundation seepage cut-off to bedrock, as the conclusions drawn from the pump test were that the aquifer was hydrogeologically confined. 3 refs., 4 tabs., 9 figs.

  19. Increasing dam safety with multi beam sonar

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, M. [SwedPower AB, Stockholm (Sweden); Cederstrom, M.O. [Vattenfall AB, Stockholm (Sweden); Deborg, J. [SwedPower AB, Alvkarleby (Sweden)

    2004-09-01

    Multi-beam sonar technology has been introduced to Vattenfall's dam safety program. Vattenfall is the major energy producer in Sweden and the third largest utility in Europe. Embankment dams are subject to processes such as erosion, settlement and sinkholes. The new portable multi-beam echo sounder system is an important tool to detect minor damages and to intervene before they evolve into expensive or hazardous situations. A first survey of the upstream slope of a rockfill dam with this method provides a topographic map indicating the location of anomalies such as internal erosion or piping. Multi-beam sonar works by combining GPS-RTK positioning, gyro motion sensing, a multi-beam sonar and 3-dimensional digital terrain programs. Vattenfall is using the system to verify and monitor all high hazard rockfill dams in Sweden to ensure long-term stability. The data will be stored as a fingerprint for comparison with future surveys in 15 to 20 years as part of routine safety evaluation. This new technology can also be used to survey breakwaters, erosion of rivers and to locate submerged debris in harbours. 6 figs.

  20. A Final Test for the Big Dam

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ The water level at the Three Gorges Dam,the world's largest water control and utilization project,reached its designed highest mark on October 26,which will enable the project to fulfill its functions of flood control,power generation,navigation and water diversion.

  1. Will We. . .? Thai Dam Resource Book.

    Science.gov (United States)

    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…

  2. Resilience scales of a dammed tropical river

    Science.gov (United States)

    Calamita, Elisa; Schmid, Martin; Wehrli, Bernhard

    2017-04-01

    Artificial river impoundments disrupt the seasonality and dynamics of thermal, chemical, morphological and ecological regimes in river systems. These alterations affect the aquatic ecosystems in space and time and specifically modify the seasonality and the longitudinal gradients of important biogeochemical processes. Resilience of river systems to anthropogenic stressors enables their recovery along the flow path; however little is known about the longitudinal distance that rivers need to partially restore their physical, chemical and biological integrity. In this study, the concept of a "resilience scale" will be explored for different water quality parameters downstream of Kariba dam, the largest artificial lake in the Zambezi basin (South-East Africa). The goal of this project is to develop a modelling framework to investigate and quantify the impact of large dams on downstream water quality in tropical context. In particular, we aim to assess the degree of reversibility of the main downstream alterations (temperature, oxygen, nutrients) and consequently the quantification of their longitudinal extent. Coupling in-situ measurements with hydraulic and hydrological parameters such as travel times, will allow us to define a physically-based parametrization of the different resilience scales for tropical rivers. The results will be used for improving future dam management at the local scale and assessing the ecological impact of planned dams at the catchment scale.

  3. Fish reproductive guilds downstream of dams.

    Science.gov (United States)

    Vasconcelos, L P; Alves, D C; Gomes, L C

    2014-11-01

    Fish reproductive guilds were used to evaluate the responses of species with different reproductive strategies during two different periods of post-dam construction. The data used for the comparisons were collected in the upper Paraná River floodplain (Brazil), downstream of the Porto Primavera dam, 2 and 10 years after impoundment. The abundance (catch per unit effort, CPUE), species richness, evenness and structure of communities, all within reproductive guilds, were used to test the hypothesis that these metrics vary spatially and temporally. The influence of damming on species structure and the diversity of fish reproductive guilds varied spatiotemporally, and species with opportunistic reproductive strategies tended to be less affected. Conversely, long-distance migratory species responded more markedly to spatiotemporal variations, indicating that the ecosystem dynamics exert greater effects on populations of these species. Thus, the effects of a dam, even if attenuated, may extend over several years, especially downstream. This finding emphasizes the importance of maintaining large undammed tributaries downstream of reservoirs.

  4. Modelling approach for gravity dam break analysis

    Directory of Open Access Journals (Sweden)

    Boussekine Mourad

    2016-09-01

    Full Text Available The construction of dams in rivers can provide considerable benefits such as the supply of drinking and irrigation water; however the consequences which would result in the event of their failure could be catastrophic. They vary dramatically depending on the extent of the inundation area, the size of the population at risk.

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

    Science.gov (United States)

    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.

  6. Expectations of immortality: dam safety management into the next millennium

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, M.D. [Tonkin and Taylor International Ltd., Auckland, (New Zealand)

    1999-07-01

    Topics concerning the problems associated with older and aging dams are considered including: what can be done to extent the lifetime of an old dam, the decision to decommission a dam based on a value judgment that the risk of maintaining the dam is too great for society's acceptance, the possibility of change in the level of risk tolerance with time in a technological environment, traditional surveillance methods used by dam owners in the Y2K situation, and the unreality of dam immortality. Trends and means for preserving older dams for their owner's purposes are outlined, as well as their lifetime compared to that of the downstream systems they serve. Despite the fact that we live in a throwaway society, dam owners cannot just leave their dam asset when they are through with using it. Someone has to maintain the dam, or ensure that it is safely decommissioned when the owner is finished with it. On a worldwide scale the available pool of experienced dam engineers is shrinking. This problem needs to be addressed by a shift towards operating and dam safety management skills based on a firm awareness of dam design principles. A shift in society's expectations has occurred such that dam designers and owners must now recognize the impact a dam can have both on its natural and social environments. Because of the increasing emphasis on paying attention to the impacts of people's activities on the planet, engineers more than anyone else must have a significant influence in that direction. 9 refs.

  7. Compilation of Water-Resources Data for Montana, Water Year 2006

    Science.gov (United States)

    Ladd, P. B.; Berkas, W.R.; White, M.K.; Dodge, K.A.; Bailey, F.A.

    2007-01-01

    The U.S. Geological Survey, Montana Water Science Center, in cooperation with other Federal, State, and local agencies, and Tribal governments, collects a large amount of data pertaining to the water resources of Montana each water year. This report is a compilation of Montana site-data sheets for the 2006 water year, which consists of records of stage and discharge of streams; water quality of streams and ground water; stage and contents of lakes and reservoirs; water levels in wells; and precipitation data. Site-data sheets for selected stations in Canada and Wyoming also are included in this report. The data for Montana, along with data from various parts of the Nation, are included in 'Water-Resources Data for the United States, Water Year 2006', which is published as U.S. Geological Survey Water-Data Report WDR-US-2006 and is available at http://pubs.water.usgs.gov/wdr2006. Additional water year 2006 data collected at crest-stage gage and miscellaneous-measurement stations were collected but were not published. These data are stored in files of the U.S. Geological Survey Montana Water Science Center in Helena, Montana, and are available on request.

  8. The Montana ALE (Autonomous Lunar Excavator) Systems Engineering Report

    Science.gov (United States)

    Hull, Bethanne J.

    2012-01-01

    On May 2 1-26, 20 12, the third annual NASA Lunabotics Mining Competition will be held at the Kennedy Space Center in Florida. This event brings together student teams from universities around the world to compete in an engineering challenge. Each team must design, build and operate a robotic excavator that can collect artificial lunar soil and deposit it at a target location. Montana State University, Bozeman, is one of the institutions selected to field a team this year. This paper will summarize the goals of MSU's lunar excavator project, known as the Autonomous Lunar Explorer (ALE), along with the engineering process that the MSU team is using to fulfill these goals, according to NASA's systems engineering guidelines.

  9. CENTENNIAL MOUNTAINS WILDERNESS STUDY AREA, MONTANA AND IDAHO.

    Science.gov (United States)

    Witkind, Irving J.; Ridenour, James

    1984-01-01

    A mineral survey conducted within the Centennial Mountains Wilderness study area in Montana and Idaho showed large areas of probable and substantiated resource potential for phosphate. Byproducts that may be derived from processing the phosphate include vanadium, chromium, uranium, silver, fluorine, and the rare earths, lanthanum and yttrium. Results of a geochemical sampling program suggest that there is little promise for the occurrence of base and precious metals in the area. Although the area contains other nonmetallic deposits, such as coal, building stone, and pumiceous ash they are not considered as mineral resources. There is a probable resource potential for oil and gas and significant amounts may underlie the area around the Peet Creek and Odell Creek anticlines.

  10. National Uranium Resource Evaluation: Ashton Quadrangle, Idaho, Montana, and Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Suekawa, H.S.; Merrick, D.; Clayton, J.; Rumba, S.

    1982-07-01

    The Ashton Quadrangle, Idaho, Montana, and Wyoming, was evaluated to identify and delineate areas containing environments favorable for uranium deposits, using criteria developed for the National Uranium Resource Evaluation program. General surface reconnaissance, radiometric traverses, and geochemical sampling were carried out in all geologic environments within the quadrangle. Aerial radiometric data were evaluated, and anomalies were examined in the field. Fourteen uranium occurrences were noted in the study area. Only one environment, the phosphorites of the Permian Phosphoria Formation, is considered favorable for uranium deposition. The unfavorable environments include: limestones, sandstones, coal and carbonaceous shales, volcanics, Precambrian metamorphics, and Tertiary basins. Unevaluated areas include the John D. Rockefeller Jr. Memorial Parkway and Yellowstone and Grand Teton National Parks, where park service regulations prohibit detailed investigations.

  11. Shoot Tip Culture of Arnica montana for Micropropagation.

    Science.gov (United States)

    Conchou, O; Nichterlein, K; Vömel, A

    1992-02-01

    Multiple shoots were regenerated from shoot tips of ARNICA MONTANA on MS and B5 media supplemented with BA (1 mg/l) and NAA (0.1 mg/l). Sections of 1-2 mm in length cultured from IN VITRO germinated seedlings regenerated 7.7 (mean) shoots on the MS medium, whereas sections cultured from greenhouse plants regenerated 9.0 (mean) shoots on the B5 medium within 6 weeks. Subsequent subcultures of shoots on the same media but without NAA resulted in similar or lower multiplication rates (1.6 to 3.1 in 3 weeks). Shoot development was promoted, whereas shoot initiation was simultaneously inhibited by the addition of activated charcoal to the media. Rooting was induced by culturing shoots from seedling as well as from greenhouse plant shoot tips on MS or B5 medium supplemented with NAA. The plantlets were transplanted into soil and grown successfully under greenhouse and field conditions.

  12. RESEARCH ON SEEPAGE MONITORING MODEL OF EARTH-ROCK DAM

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    With the characteristics of seepage flow in earth-rock dams, a seepage monitoring model was established based on the finite element method for 3-D seepage flow together with observed data and was used to analyze and monitor the seepage of dams. In order to find out and monitor the seepage status of the whole dam, the separation of seepage amount for dam body, dam foundation and side banks was made theoretically by using the model. Practical example shows that the accuracy of computed results is satisfactory and the separation results are more objective.

  13. Wegener’s granulomatosis and environmental factors in Western Montana

    Directory of Open Access Journals (Sweden)

    Andrew Samuel Zeft

    2010-12-01

    Full Text Available The objective of our study was to determine whether exposure to silica or other environmental factors is associated with developing Wegener’s granulomatosis (WG, in a geographically isolated region of Western Montana. We sought to identify and interview all cases of WG diagnosed during 1993-2006 among residents of a ten-county region of Western Montana, as well as a group of demographically similar controls (n=39 without autoimmune disease. In the interview, we ascertained occupational silica and other exposures (metals, solvents, pesticides, tobacco. We enumerated 32 cases of WG, of whom 27 were included in the case-control study. Overall, a history of silica exposure was not associated with WG (OR = 0.68, 95% CI: 0.13-3.27, although there was a suggestion of increase in risk among persons with relatively recent (OR=2.67, 95% CI: 0.54-17.2, heavy (OR=1.82, 95% CI: 0.09-112.9, and prolonged (OR=1.53, 95% CI: 0.16-20.0 exposures. A history of having worked in the mining industry was associated with WG (six cases including three with no silica exposure, zero controls, lower 95% CI: 1.53. Risk was not associated with occupational or aerial pesticide exposure, but with residential rodenticide use (OR=12.15, 95% CI: 1.54-552. Occupational exposure to metals or solvents was not associated with WG, nor was a history of cigarette smoking. Results of earlier studies of WG support the hypothesis that silica exposure adversely influences the risk of developing WG. Our small study of WG failed to identify an association with silica overall, but the results are compat­ible with an increased risk in persons with relatively heavy, prolonged, and/or recent exposure.

  14. Effects of phonophoresis with Arnica montana onto acute inflammatory process in rat skeletal muscles: an experimental study.

    Science.gov (United States)

    Alfredo, Patrícia P; Anaruma, Carlos A; Pião, Antônio C S; João, Silvia M A; Casarotto, Raquel A

    2009-05-01

    This study aimed at verifying the effects of phonophoresis associated with Arnica montana on the acute phase of an inflammatory muscle lesion. Forty Wistar male rats (300+/-50 g), of which the Tibialis Anterior muscle was surgically lesioned, were divided into four groups (n=10 each): control group received no treatment; the ultrasound group (US) was treated in pulsed mode with 1-MHz frequency, 0.5 W/cm(2) intensity (spatial and temporal average - SATA), duty cycle of 1:2 (2 ms on, 4 ms off, 50%), time of application 3 min per session, one session per day, for 3 days; the phonophoresis or ultrasound plus arnica (US+A) group was treated with arnica with the same US parameters plus arnica gel; and the arnica group (A) was submitted to massage with arnica gel, also for 3 min, once a day, for 3 days. Treatment started 24h after the surgical lesion. On the 4th day after lesion creation, animals were sacrificed and sections of the lesioned, inflamed muscle were removed for quantitative (mononuclear and polymorphonuclear cell count) and qualitative histological analysis. Collected data from the 4 groups were statistically analyzed and the significance level set at p<0.05. Results show higher mononuclear cell density in all three treated groups with no significant difference between them, but values were significantly different (p<0.0001) when compared to control group's. As to polymorphonuclear cell density, significant differences were found between control group (p=0.0134) and US, US+A and A groups; the arnica group presented lesser density of polymorphonuclear cells when compared (p=0.0134) to the other groups. No significant difference was found between US and US+A groups. While the massage with arnica gel proved to be an effective anti-inflammatory on acute muscle lesion in topic use, these results point to ineffectiveness of Arnica montana phonophoresis, US having seemingly checked or minimized its anti-inflammatory effect.

  15. Performance of a surface bypass structure to enhance juvenile steelhead passage and survival at Lower Granite Dam, Washington

    Science.gov (United States)

    Adams, Noah S.; Plumb, John M.; Perry, Russell W.; Rondorf, Dennis W.

    2014-01-01

    An integral part of efforts to recover stocks of Pacific salmon Oncorhynchus spp. and steelhead O. mykiss in Pacific Northwest rivers is to increase passage efficacy and survival of juveniles past hydroelectric dams. As part of this effort, we evaluated the efficacy of a prototype surface bypass structure, the removable spillway weir (RSW), installed in a spillbay at Lower Granite Dam, Washington, on the Snake River during 2002, 2003, 2005, and 2006. Radio-tagged juvenile steelhead were released upstream from the dam and their route of passage through the turbines, juvenile bypass, spillway, or RSW was recorded. The RSW was operated in an on-or-off condition and passed 3–13% of the total discharge at the dam when it was on. Poisson rate models were fit to the passage counts of hatchery- and natural-origin juvenile steelhead to predict the probability of fish passing the dam. Main-effect predictor variables were RSW operation, diel period, day of the year, proportion of flow passed by the spillway, and total discharge at the dam. The combined fish passage through the RSW and spillway was 55–85% during the day and 37–61% during the night. The proportion of steelhead passing through nonturbine routes was 95% when the RSW was on during the day. The ratio of the proportion of steelhead passed to the proportion of water passing the RSW was from 6.3:1 to 10.0:1 during the day and from 2.7:1 to 5.2:1 during the night. Steelhead passing through the RSW exited the tailrace about 15 min faster than fish passing through the spillway. Mark–recapture single-release survival estimates for steelhead passing the RSW ranged from 0.95 to 1.00. The RSW appeared to be an effective bypass structure compared with other routes of fish passage at the dam.

  16. Mining dams safety regulations : where does Canada stand?

    Energy Technology Data Exchange (ETDEWEB)

    Priscu, C. [AMEC, Winnipeg, MB (Canada); Small, A. [AMEC Earth and Environmental Ltd., Fredericton, NB (Canada); Lupo, J. [AMEC, Englewood, CO (United States); Diaz, M. [AMEC, Ashford, Kent (United Kingdom); Davies, M. [AMEC, Vancouver, BC (Canada); Musse, M. [AMEC, Santiago (Chile)

    2009-07-01

    While many jurisdictions in Canada use the Canadian Dam Association (CDA) dam safety guidelines, their applicability to the safety of mining dams is limited. Mining dams are some of the largest containment structures in the world, and impound millions of cubic meters of mine process residues in both solid and liquid form. This study presented a review of dam safety regulatory frameworks for mining dams located in various countries. The aim of the study was to compare the Canadian framework with various dam safety legislations in order to evaluate Canada's current status and recommend best practices in dam safety regulations. The study reviewed incremental consequence classifications; best practices in operation, surveillance and maintenance manuals and procedures; emergency preparedness plans; and dam safety inspections. The study showed that Canada has limited documentation regulating the safe management of tailings facilities, and does not have an all-encompassing national guideline for mining dams. It was concluded that an incremental consequence classification (ICC) system should be developed specifically for mining dams. 12 refs.

  17. Seismic failure modes and seismic safety of Hardfill dam

    Directory of Open Access Journals (Sweden)

    Kun XIONG

    2013-04-01

    Full Text Available Based on microscopic damage theory and the finite element method, and using the Weibull distribution to characterize the random distribution of the mechanical properties of materials, the seismic response of a typical Hardfill dam was analyzed through numerical simulation during the earthquakes with intensities of 8 degrees and even greater. The seismic failure modes and failure mechanism of the dam were explored as well. Numerical results show that the Hardfill dam remains at a low stress level and undamaged or slightly damaged during an earthquake with an intensity of 8 degrees. During overload earthquakes, tensile cracks occur at the dam surfaces and extend to inside the dam body, and the upstream dam body experiences more serious damage than the downstream dam body. Therefore, under the seismic conditions, the failure pattern of the Hardfill dam is the tensile fracture of the upstream regions and the dam toe. Compared with traditional gravity dams, Hardfill dams have better seismic performance and greater seismic safety.

  18. Dam failure analysis for the Lago El Guineo Dam, Orocovis, Puerto Rico

    Science.gov (United States)

    Gómez-Fragoso, Julieta; Heriberto Torres-Sierra,

    2016-08-09

    The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, completed hydrologic and hydraulic analyses to assess the potential hazard to human life and property associated with the hypothetical failure of the Lago El Guineo Dam. The Lago El Guineo Dam is within the headwaters of the Río Grande de Manatí and impounds a drainage area of about 4.25 square kilometers.The hydrologic assessment was designed to determine the outflow hydrographs and peak discharges for Lago El Guineo and other subbasins in the Río Grande de Manatí hydrographic basin for three extreme rainfall events: (1) a 6-hour probable maximum precipitation event, (2) a 24-hour probable maximum precipitation event, and (3) a 24-hour, 100-year recurrence rainfall event. The hydraulic study simulated a dam failure of Lago El Guineo Dam using flood hydrographs generated from the hydrologic study. The simulated dam failure generated a hydrograph that was routed downstream from Lago El Guineo Dam through the lower reaches of the Río Toro Negro and the Río Grande de Manatí to determine water-surface profiles developed from the event-based hydrologic scenarios and “sunny day” conditions. The Hydrologic Engineering Center’s Hydrologic Modeling System (HEC–HMS) and Hydrologic Engineering Center’s River Analysis System (HEC–RAS) computer programs, developed by the U.S. Army Corps of Engineers, were used for the hydrologic and hydraulic modeling, respectively. The flow routing in the hydraulic analyses was completed using the unsteady flow module available in the HEC–RAS model.Above the Lago El Guineo Dam, the simulated inflow peak discharges from HEC–HMS resulted in about 550 and 414 cubic meters per second for the 6- and 24-hour probable maximum precipitation events, respectively. The 24-hour, 100-year recurrence storm simulation resulted in a peak discharge of about 216 cubic meters per second. For the hydrologic analysis, no dam failure conditions are

  19. Ecogeomorphic feedbacks in regrowth of travertine step-pool morphology after dam decommissioning, Fossil Creek, Arizona

    Science.gov (United States)

    Fuller, Brian M.; Sklar, Leonard S.; Compson, Zacchaeus G.; Adams, Kenneth J.; Marks, Jane C.; Wilcox, Andrew C.

    2011-03-01

    intensity at the dam surface. At each magnet we record a range of hydraulic and travertine composition variables to characterize the dominant mechanism of growth: abiotic precipitation, algal growth, trapping of organic material, or in situ plant growth. We find: (1) rapid growth of travertine dams following flow restoration, averaging more than 2 cm/year; (2) growth rates decline downstream, consistent with loss of dissolved constituents because of upstream travertine deposition, but also parallel to a decline in organic content in dam surface material and a downstream shift in dominant biotic mechanism; (3) biotic mechanisms are associated with faster growth rates; and (4) correlations between hydraulic attributes and growth rates are more consistent with biotic than abiotic controls. We conclude that the strong influence of living organisms on rates of travertine growth, coupled with the beneficial effects of travertine on ecosystem dynamics, demonstrate a positive feedback between biology and geomorphology. During our two-year study period, erosive flood flows occurred causing widespread removal of travertine. The temporal distribution of travertine growth and erosion over the study period is consistent with a bimodal magnitude-frequency relation in which growth dominates except when large, infrequent storms occur. This model may be useful in other systems where biology exerts strong controls on geomorphic processes.

  20. Composition of leaf n-alkanes in three Satureja montana L. subspecies from the Balkan peninsula: ecological and taxonomic aspects.

    Science.gov (United States)

    Dodoš, Tanja; Rajčević, Nemanja; Tešević, Vele; Matevski, Vlado; Janaćković, Pedja; Marin, Petar D

    2015-01-01

    The composition of the epicuticular leaf n-alkanes of eight populations of three Satureja montana subspecies (S. montana L. subsp. pisidica (Wettst.) Šilić, S. montana L. subsp. montana, and S. montana L. subsp. variegata (Host) P. W. Ball), from central and western areas of the Balkan Peninsula was characterized by GC-FID and GC/MS analyses. In the leaf waxes, 15 n-alkane homologs with chain-lengths ranging from C21 to C35 were identified. The main n-alkane in almost all samples was n-nonacosane (C29 ), but differences in the contents of three other dominant n-alkanes allowed separating the coastal from the continental populations. The diversity and variability of the epicuticular-leaf-n-alkane patterns and their relation to different geographic and bioclimatic parameters were analyzed by several statistical methods (principal component, discriminant, and cluster analyses as well as the Mantel test). All tests showed a high correlation between the leaf n-alkane pattern and the geographical distribution of the investigated populations, confirming the differentiation between S. montana subsp. pisidica and the other two subspecies. The S. montana subsp. variegata and S. montana subsp. montana populations are geographically closer and their differentiation according to the leaf-n-alkane patterns was not clear, even though there was some indication of discrimination between them. Moreover, most of the bioclimatic parameters related to temperature were highly correlated with the differentiation of the coastal and the continental populations.