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Sample records for willow island dam

  1. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION

    International Nuclear Information System (INIS)

    K. Payette; D. Tillman

    2001-01-01

    During the period October 1, 2000 - December 31, 2000, Allegheny Energy Supply Co., LLC (Allegheny) executed a Cooperative Agreement with the National Energy Technology Laboratory to implement a major cofiring demonstration at the Willow Island Generating Station Boiler No.2. Willow Island Boiler No.2 is a cyclone boiler. Allegheny also will demonstrate separate injection cofiring at the Albright Generating Station Boiler No.3, a tangentially fired boiler. The Allegheny team includes Foster Wheeler as its primary subcontractor. Additional subcontractors are Cofiring Alternatives and N.S. Harding and Associates. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. The second quarter of the project involved completing the designs for each location. Further, geotechnical investigations proceeded at each site. Preparations were made to perform demolition on two small buildings at the Willow Island site. Fuels strategies were initiated for each site. Test planning commenced for each site. A groundbreaking ceremony was held at the Willow Island site on October 18, with Governor C. Underwood being the featured speaker

  2. Bottom-up factors influencing riparian willow recovery in Yellowstone National Park

    Science.gov (United States)

    Tercek, M.T.; Stottlemyer, R.; Renkin, R.

    2010-01-01

    After the elimination of wolves (Canis lupis L.) in the 1920s, woody riparian plant communities on the northern range of Yellowstone National Park (YNP) declined an estimated 50%. After the reintroduction of wolves in 19951996, riparian willows (Salix spp.) on YNP's northern range showed significant growth for the first time since the 1920s. However, the pace of willow recovery has not been uniform. Some communities have exceeded 400 cm, while others are still at pre-1995 levels of 250 cm max. height) willow sites where willows had escaped elk (Cervus elaphus L.) browsing with "short" willow sites that could still be browsed. Unlike studies that manipulated willow height with fences and artificial dams, we examined sites that had natural growth differences in height since the reintroduction of wolves. Tall willow sites had greater water availability, more-rapid net soil nitrogen mineralization, greater snow depth, lower soil respiration rates, and cooler summer soil temperatures than nearby short willow sites. Most of these differences were measured both in herbaceous areas adjacent to the willow patches and in the willow patches themselves, suggesting that they were not effects of varying willow height recovery but were instead preexisting site differences that may have contributed to increased plant productivity. Our results agree with earlier studies in experimental plots which suggest that the varying pace of willow recovery has been influenced by abiotic limiting factors that interact with top-down reductions in willow browsing by elk. ?? 2010 Western North American Naturalist.

  3. Water tables constrain height recovery of willow on Yellowstone's northern range.

    Science.gov (United States)

    Bilyeu, Danielle M; Cooper, David J; Hobbs, N Thompson

    2008-01-01

    Excessive levels of herbivory may disturb ecosystems in ways that persist even when herbivory is moderated. These persistent changes may complicate efforts to restore ecosystems affected by herbivores. Willow (Salix spp.) communities within the northern range in Yellowstone National Park have been eliminated or degraded in many riparian areas by excessive elk (Cervus elaphus L.) browsing. Elk browsing of riparian willows appears to have diminished following the reintroduction of wolves (Canis lupis L.), but it remains uncertain whether reduced herbivory will restore willow communities. The direct effects of elk browsing on willows have been accompanied by indirect effects from the loss of beaver (Castor canadensis Kuhl) activity, including incision of stream channels, erosion of fine sediments, and lower water tables near streams historically dammed by beaver. In areas where these changes have occurred, lowered water tables may suppress willow height even in the absence of elk browsing. We conducted a factorial field experiment to understand willow responses to browsing and to height of water tables. After four years of protection from elk browsing, willows with ambient water tables averaged only 106 cm in height, with negligible height gain in two of three study species during the last year of the experiment. Willows that were protected from browsing and had artificially elevated water tables averaged 147 cm in height and gained 19 cm in the last year of the experiment. In browsed plots, elevated water tables doubled height gain during a period of slightly reduced browsing pressure. We conclude that water availability mediates the rate of willow height gain and may determine whether willows grow tall enough to escape the browse zone of elk and gain resistance to future elk browsing. Consequently, in areas where long-term beaver absence has resulted in incised stream channels and low water tables, a reduction in elk browsing alone may not be sufficient for recovery

  4. Haggart Island dams : reconstruction/rehabilitation feasibility study : final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

    This feasibility study was conducted to identify and evaluate the range of options available for the repair or reconstruction of the Haggart Island Dams, and to provide the required information needed to decide upon the preferred solution and secure funding for the final design for reconstruction. In addition, the study presented the initial stages needed to satisfy the environmental assessment process regarding the selection of options related to the structures. Information relating to: fish habitat; flood mapping; historical flow data; condition of the dams; historical significance of the dams and their relation to the area; recreational opportunities for the area and previous public consultation records was presented. Issues regarding water level were addressed through a hydraulic analysis. Field and background data were compiled in order to establish the existing conditions of the study area. Background information regarding the natural features of the study area was presented. Safety issues were assessed in developing landscaping features and pathway planning. Details of public consultation procedures were presented. Information from stakeholders was gathered regarding recreational activities, river flow, historical and nature related issues to develop an understanding of the significance of the dams. Various design alternatives were presented, as well as details of the current, deteriorating state of the dams. 5 tabs., 24 figs.

  5. Development of Nile River islands between Old Aswan Dam and new Esna barrages

    Directory of Open Access Journals (Sweden)

    Yasser Raslan

    2015-04-01

    Full Text Available This paper investigates the development of Nile River islands in the first reach which extends between Aswan and new Esna barrages. A wide range of data compiled and used in this investigation which include produced maps in 1939, 1982 and 2003, and hydrological data. Compiled data drew a complete picture for up-to-date information on morphological changes since 1939. The analysis indicated that islands length; thus, area has reduced since 1939. Also, islands tend to reshape by elongating. The reduction in area is attributed in part to the merging of islands in either bank and adjustment of the river to the new flow conditions after the operation of High Aswan Dam. El-Mansouria Island which is the largest island in area was focused on. Recent human interferences accelerated the merging of island in the west bank. Consequently, river morphology has changed around the islands.

  6. The impact of erosion protection by Stone Dams on Salt-Marsh vegetation on Two Wadden Sea Barrier Islands

    NARCIS (Netherlands)

    Loon-Steensma, van J.M.; Slim, P.A.

    2013-01-01

    This paper describes and quantifies the effect of low stone dams on the extent and composition of salt-marsh habitats on two Dutch Wadden islands: Terschelling and Ameland. The stone dams were built to prevent erosion of the salt-marsh edge. Analyses of a series of aerial photographs taken between

  7. DESIGNING AND OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    Energy Technology Data Exchange (ETDEWEB)

    K. Payette; D. Tillman

    2004-06-01

    During the period July 1, 2000-March 31, 2004, Allegheny Energy Supply Co., LLC (Allegheny) conducted an extensive demonstration of woody biomass cofiring at its Willow Island and Albright Generating Stations. This demonstration, cofunded by USDOE and Allegheny, and supported by the Biomass Interest Group (BIG) of EPRI, evaluated the impacts of sawdust cofiring in both cyclone boilers and tangentially-fired pulverized coal boilers. The cofiring in the cyclone boiler--Willow Island Generating Station Unit No.2--evaluated the impacts of sawdust alone, and sawdust blended with tire-derived fuel. The biomass was blended with the coal on its way to the combustion system. The cofiring in the pulverized coal boiler--Albright Generating Station--evaluated the impact of cofiring on emissions of oxides of nitrogen (NO{sub x}) when the sawdust was injected separately into the furnace. The demonstration of woody biomass cofiring involved design, construction, and testing at each site. The results addressed impacts associated with operational issues--capacity, efficiency, and operability--as well as formation and control of airborne emissions such as NO{sub x}, sulfur dioxide (SO{sub 2}2), opacity, and mercury. The results of this extensive program are detailed in this report.

  8. The long-term legacy of geomorphic and riparian vegetation feedbacks on the dammed Bill Williams River, Arizona, USA

    Science.gov (United States)

    Kui, Li; Stella, John C.; Shafroth, Patrick B.; House, P. Kyle; Wilcox, Andrew C.

    2017-01-01

    On alluvial rivers, fluvial landforms and riparian vegetation communities codevelop as a result of feedbacks between plants and abiotic processes. The influence of vegetation on river channel and floodplain geomorphology can be particularly strong on dammed rivers with altered hydrology and reduced flood disturbance. We used a 56-year series of aerial photos on the dammed Bill Williams River (Arizona, USA) to investigate how (a) different woody riparian vegetation types influence river channel planform and (b) how different fluvial landforms drive the composition of riparian plant communities over time. We mapped vegetation types and geomorphic surfaces and quantified how relations between fluvial and biotic processes covaried over time using linear mixed models. In the decades after the dam was built, woody plant cover within the river's bottomland nearly doubled, narrowing the active channel by 60% and transforming its planform from wide and braided to a single thread and more sinuous channel. Compared with native cottonwood–willow vegetation, nonnative tamarisk locally induced a twofold greater reduction in channel braiding. Vegetation expanded at different rates depending on the type of landform, with tamarisk cover on former high-flow channels increasing 17% faster than cottonwood–willow. Former low-flow channels with frequent inundation supported a greater increase in cottonwood–willow relative to tamarisk. These findings give insight into how feedbacks between abiotic and biotic processes in river channels accelerate and fortify changes triggered by dam construction, creating river systems increasingly distinct from predam ecological communities and landforms, and progressively more resistant to restoration of predam forms and processes.

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

    Science.gov (United States)

    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 ...

  10. 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...

  11. Evaluation report. Willow; Evalueringsrapport. Pil

    Energy Technology Data Exchange (ETDEWEB)

    Bang Bilgaard, H. [AgroTech A/S, Skejby, Aarhus (Denmark); Eide, T.; Gertz, F. [Videncentret for Landbrug, Skejby, Aarhus (Denmark)] [and others

    2012-10-15

    This evaluation report brings together the main findings of willows activities in the BioM project in the period 2010-2012. The report contains sections relating to growing and cultivation conditions, energy production, environmental effects, landscape aspects, harvesting techniques, economics, and organization, marketing, and business effects, and a description of willow cultivation on a large scale in the project area in western Jutland, Denmark. The report concludes with an overall assessment of willow cultivation for the production of sustainable bioenergy. (LN)

  12. Spatial extent and dynamics of dam impacts on tropical island freshwater fish assemblages

    Science.gov (United States)

    Cooney, Patrick B.; Kwak, Thomas J.

    2013-01-01

    Habitat connectivity is vital to the persistence of migratory fishes. Native tropical island stream fish assemblages composed of diadromous species require intact corridors between ocean and riverine habitats. High dams block fish migration, but low-head artificial barriers are more widespread and are rarely assessed for impacts. Among all 46 drainages in Puerto Rico, we identified and surveyed 335 artificial barriers that hinder fish migration to 74.5% of the upstream habitat. We also surveyed occupancy of native diadromous fishes (Anguillidae, Eleotridae, Gobiidae, and Mugilidae) in 118 river reaches. Occupancy models demonstrated that barriers 2 meters (m) high restricted nongoby fish migration and extirpated those fish upstream of 4-m barriers. Gobies are adapted to climbing and are restricted by 12-m barriers and extirpated upstream of 32-m barriers. Our findings quantitatively illustrate the extensive impact of low-head structures on island stream fauna and provide guidance for natural resource management, habitat restoration, and water development strategies.

  13. A Natural History Summary and Survey Protocol for the Southwestern Willow Flycatcher

    Science.gov (United States)

    Sogge, Mark K.; ,; Ahlers, Darrell; ,; Sferra, Susan J.; ,

    2010-01-01

    The Southwestern Willow Flycatcher (Empidonax traillii extimus) has been the subject of substantial research, monitoring, and management activity since it was listed as an endangered species in 1995. When proposed for listing in 1993, relatively little was known about the flycatcher's natural history, and there were only 30 known breeding sites supporting an estimated 111 territories rangewide (Sogge and others, 2003a). Since that time, thousands of presence/absences surveys have been conducted throughout the historical range of the flycatcher, and many studies of its natural history and ecology have been completed. As a result, the ecology of the flycatcher is much better understood than it was just over a decade ago. In addition, we have learned that the current status of the flycatcher is better than originally thought: as of 2007, the population was estimated at approximately 1,300 territories distributed among approximately 280 breeding sites (Durst and others, 2008a). Concern about the Southwestern Willow Flycatcher on a rangewide scale was brought to focus by Unitt (1987), who described declines in flycatcher abundance and distribution throughout the Southwest. E. t. extimus populations declined during the 20th century, primarily because of habitat loss and modification from activities, such as dam construction and operation, groundwater pumping, water diversions, and flood control. In 1991, the U.S. Fish and Wildlife Service (USFWS) designated the Southwestern Willow Flycatcher as a candidate category 1 species (U.S. Fish and Wildlife Service, 1991). In July 1993, the USFWS proposed to list E. t. extimus as an endangered species and to designate critical habitat under the Act (U.S. Fish and Wildlife Service, 1993). A final rule listing E. t. extimus as endangered was published in February 1995 (U.S. Fish and Wildlife Service, 1995); critical habitat was designated in 1997 (U.S. Fish and Wildlife Service, 1997). The USFWS Service released a Recovery Plan for

  14. Post-dam vegetation changes and small mammal populations in the Peace-Athabasca delta

    International Nuclear Information System (INIS)

    Pfister, O.

    1993-01-01

    Research aimed at monitoring wildlife populations is a useful way to estimate the impact and consequences of hydroelectric projects on northern deltas. Such studies could provide valuable insights on the potential effect of the drying of deltas in the context of global climate change. The Peace-Athabasca River Delta, one of the most extensive northern inland deltas in the western hemisphere, represents a unique site to study such effects. Construction of the Bennett Dam in 1968 has had serious effects on the delta's ecological integrity; the resulting lower water levels and colonization of grass meadow communities by willows and the movement of shorelines has affected wildlife distribution and population levels. A study was conducted to estimate the impact of the invasion of grass meadows by willows on small rodent populations in the delta. Live trapping grids were established at three sites. Population estimates were obtained by the minimum number known method and used to calculate biomass of small mammals in willow and meadow grids. Mean trapping estimates (MTEs) of adult meadow voles ranged from under 1 per hectare on willow grids to 28 per hectare on meadow grids. On willow grids only, MTEs for adult populations of deer mice, red-backed voles, and meadow jumping mice reached 6, 6, and less than 1 per hectare respectively. It is estimated that the development of grass meadows into willow shrublands over the next 20-40 y could result in a loss of over 50% of the biomass of small rodents present in 1976. This should have a negative effect on the foraging efficiency and productivity of secondary consumers such as weasel and owl. 109 refs., 16 figs., 29 tabs

  15. A profile and analysis of willow growers in Sweden

    International Nuclear Information System (INIS)

    Rosenqvist, H.; Roos, A.; Ling, E.; Hektor, B.

    1999-01-01

    Willow plantations on Swedish farmland increased considerably between 1991 and 1996. The main driving forces behind this development were (1) the 1991 introduction of an agriculture deregulation policy in Sweden which created lower grain prices and simultaneously introduced compensation for set-aside land and subsidies for willow plantations on surplus arable land, (2) higher taxes on fossil fuels, and (3) the existence of a biofuel market in Sweden based on forest fuels. This paper presents a statistical study of 1,158 willow growers in southern and central-eastern Sweden. The resulting profile of growers will help policy makers and agents in the bioenergy business design information campaigns and marketing strategies. Willow growers are described according to geographical distribution, willow parcel sizes, farm sizes, and farm types. They are compared with the population of farmers who are not growing willow. Willow growers are more often between 50-65 years of age, and they have larger farms than non-willow growers. They are less often focused on animal and milk production and more often on cereal and food crop production than are other farmers. (author)

  16. Willow Bark

    Science.gov (United States)

    ... willow bark extract, ginger root concentrate, boswellia extract, turmeric root extract, cayenne, and hyaluronic acid (Instaflex Joint ... Sensitivity to aspirin: People with ASTHMA, STOMACH ULCERS, DIABETES, GOUT, HEMOPHILIA, HYPOPROTHROMBINEMIA, or KIDNEY or LIVER DISEASE ...

  17. Adsorption Property and Mechanism of Oxytetracycline onto Willow Residues

    Directory of Open Access Journals (Sweden)

    Di Wang

    2017-12-01

    Full Text Available To elucidate the adsorption property and the mechanism of plant residues to reduce oxytetracycline (OTC, the adsorption of OTC onto raw willow roots (WR-R, stems (WS-R, leaves (WL-R, and adsorption onto desugared willow roots (WR-D, stems (WS-D, and leaves (WL-D were investigated. The structural characterization was analyzed by scanning electron microscopy, Fourier-transform infrared spectra, and an elemental analyzer. OTC adsorption onto the different tissues of willow residues was compared and correlated with their structures. The adsorption kinetics of OTC onto willow residues was found to follow the pseudo-first-order model. The isothermal adsorption process of OTC onto the different tissues of willow residues followed the Langmuir and Freundlich model and the process was also a spontaneous endothermic reaction, which was mainly physical adsorption. After the willow residues were desugared, the polarity decreased and the aromaticity increased, which explained why the adsorption amounts of the desugared willow residues were higher than those of the unmodified residues. These observations suggest that the raw and modified willow residues have great potential as adsorbents to remove organic pollutants.

  18. Songbird response to increased willow (Salix spp.) growth in Yellowstone's northern range.

    Science.gov (United States)

    Baril, Lisa M; Hansen, Andrew J; Renkin, Roy; Lawrence, Rick

    2011-09-01

    After nearly a century of height suppression, willows (Salix spp.) in the northern range of Yellowstone National Park, U.S.A., are increasing in height growth as a possible consequence of wolf (Canis lupus) restoration, climate change, or other factors. Regardless of the drivers, the recent release of this rare but important habitat type could have significant implications for associated songbirds that are exhibiting declines in the region. Our objective was to evaluate bird response to releasing willows by comparing willow structure and bird community composition across three willow growth conditions: height suppressed, recently released, and previously tall (i.e., tall prior to the height increase of released willows). Released and previously tall willows exhibited high and similar vertical structure, but released willows were significantly lower in horizontal structure. Suppressed willows were significantly shorter and lower in horizontal cover than released or previously tall willows. Bird richness increased along a gradient from lowest in suppressed to highest in previously tall willows, but abundance and diversity were similar between released and previously tall willows, despite lower horizontal cover in the released condition. Common Yellowthroat (Geothlypis trichas) and Lincoln's Sparrow (Melospiza lincolnii) were found in all three growth conditions; however, Yellow Warbler (Dendroica petechia), Warbling Vireo (Vireo gilvus), Willow Flycatcher (Empidonax traillii), and Song Sparrow (Melospiza melodii) were present in released and previously tall willows only. Wilson's Warbler (Wilsonia pusilla) was found in previously tall willows only, appearing to specialize on tall, dense willows. The results of our a priori habitat models indicated that foliage height diversity was the primary driver of bird richness, abundance, and diversity. These results indicate that vertical structure was a more important driver of bird community variables than horizontal

  19. Selection of Willows (Salix sp. for Biomass Production

    Directory of Open Access Journals (Sweden)

    Davorin Kajba

    2014-12-01

    Full Text Available Background and Purpose: Willows compared with other species are the most suitable for biomass production in short rotations because of their very abundant growth during the first years. Nowadays, in Croatia, a large number of selected and registered willow clones are available. The main objective of the research should be to find genotypes which, with minimum nutrients, will produce the maximum quantity of biomass. Material and Methods: Clonal test of the arborescent willows include the autochthonous White Willow (Salix alba, interracial hybrids of the autochthonous White Willow and the English ‘cricket’ Willow (S. alba var. calva, interspecies hybrids (S. matsudana × S. alba, as well as multispecies hybrids of willows. Average production of dry biomass (DM∙ha-1∙a-1 per hectare was estimated in regard to the clone, survival, spacing and the number of shoots per stump. Results: The highest biomass production as well as the best adaptedness and phenotypic stability on testing site was shown by clones (‘V 374’, ‘V 461’, ‘V 578’ from 15.2 - 25.0 t∙DM∙ha-1∙a-1 originated from backcross hybrid S. matsudana × (S. matsudana × S. alba and by one S. alba clone (‘V 95’, 23.1 - 25.7 t∙DM∙ha-1∙a-1. These clones are now at the stage of registration and these results indicate significant potential for further breeding aimed at biomass production in short rotations. Conclusions: Willow clones showed high biomass production on marginal sites and dry biomass could be considerably increased with the application of intensive silvicultural and agro technical measures. No nutrition or pest control measures were applied (a practice otherwise widely used in intensive cultivation system, while weed vegetation was regulated only at the earliest age.

  20. Wynoochee Dam Foundation Report

    Science.gov (United States)

    1988-01-01

    schists and in propylitized andesite volcanic rocks. Tests on chlorite-bearing graywackes (Lumni Island and Robe Quarry, Seattle District) and... propylitized chlorite-bearing andesites (Blue River and Lookout Point Dams, Portland District) have shown these rocks to be durable materials with only minor

  1. Drying characteristics of willow chips and stems

    NARCIS (Netherlands)

    Gigler, J.K.; Loon, van W.K.P.; Seres, I.; Meerdink, G.; Coumans, W.J.

    2000-01-01

    In supply chains of willow (Salix viminalis) biomass to energy plants, drying is advisable in order to enable safe long-term storage, increase boiler efficiency and reduce gaseous emissions. To gain insight into the drying process, drying characteristics of willow chips and stems were investigated

  2. Underground dams for irrigation supplies in coastal limestone aquifer, Okinawa, Japan

    Science.gov (United States)

    Yasumoto, J.; Nakano, T.; Nawa, N.

    2011-12-01

    The use of underground dams to store water in regions with arid or tropical climates is a method that has received considerable attention in the last few decades. And now, for the tropical and subtropical islands that are highly vulnerable to climate change underground dams have been attracting attention again as a method of groundwater management. Okinawa Prefecture is Japan's southernmost prefecture, which consists of hundreds of islands in a chain over 1,000 km long, called the Ryukyu Islands which extend southwest from Kyushu to Taiwan. The national irrigation project of the Ryukyu Islands has been carried out, and several underground dams have been constructed. The Komesu and Giiza underground dams are first full scale underground dam facilities constructed for irrigation in Japan. The Komesu underground dam is a salt-water proof type. It prevents salt-water intrusion and provides storage fresh-water for irrigation in coastal limestone aquifer. Giiza underground dam is a dam up type for storage of fresh-water. These groundwater reservoirs are located in the coastal region of southern part of Okinawa (main island), where Ryukyu limestone is extensively distributed. We studied the behaviour of groundwater flow, saltwater intrusion and nitrate nitrogen (NO3-N) in groundwater in this region by using observation data of groundwater and springs through long term (from 1993 to 2010) monitoring. And, a groundwater flow and salt-water intrusion analysis have been conducted with three dimensional numerical model applied to these dam reservoir areas. The MODFLOW-NWT with SWI code and PEST was used to simulate the complex groundwater flow patterns. Through the comparison with simulation and observed data, it was concluded that the cut off wall of underground dams effectively stores the groundwater and prevents the salt-water intrusion in the reservoir areas. The observed groundwater levels at the reservoir areas were almost reproduced by the numerical model, but there

  3. Willow wood production on radionuclide polluted areas

    Directory of Open Access Journals (Sweden)

    Rodkin Oleg I.

    2010-01-01

    Full Text Available ABSTRACT: One of the key environmental problems in Belarus is effective use of agricultural lands contaminated by radionuclide due to the Chernobyl disaster. The alternative method to traditional agricultural crops is fast growing willow cultivation. It is possible to use biomass of willow as renewable energy source. The goal of our investigation was the estimation of environmental aspects of willow wood production on polluted areas. The field study experiments (2007-2010 were conducted at Krichev district of Mogilev region in eastern Belarus. This region characterized by high level of Cs-137 contamination as well as high level of heavy metals pollution. In the first stage of experiments, the concentration of cesium-137 in different parts of willow biomass had been measured and transfer factor calculated. The measuring had been done for leaves, roots, and wood. To control cesium-137 accumulation in willow biomass we apply different types (nitrogen N, phosphorus P and potassium K and dose of fertilizer. The experiments show that potassium mineral fertilizer is the key factor for radionuclide accumulation control. The optimal dose of potassium is 90 kg per hectare. On the base of experimental results the model of cesium-137 accumulation in the wood for a 21 year has been developed. In accordance with calculation to the end of willow cultivation (21 year concentration of cesium-137 in wood will not be higher than permitted even with the level of cesium-137 contamination in the soil 1480 kBq/m2 (maximum 140 kqB/m2 with permitted level for firewood is 740 Bq/kg.. The concentration of cesium-137 in the roots increases gradually and get maximum in 21 year (3000 kqB/m2. Our results confirm that in the sum about 0.8 million hectares of radionuclide polluted arable lands partly excluded from agricultural practice in Belarus could be used for willow biomass production.

  4. Black Willow

    Science.gov (United States)

    R. M. Krinard

    1980-01-01

    Black willow and other species of Salix together comprise a majority of the stocking. Cottonwood is the chief associate, particularly in the early stages, but green ash, sycamore, pecan, persimmon, waterlocust, American elm, baldcypress, red maple, sugarberry, box-elder, and in some areas, silver maple are invaders preceding the next successional stage.

  5. Effects of dam-induced landscape fragmentation on amazonian ant-plant mutualistic networks.

    Science.gov (United States)

    Emer, Carine; Venticinque, Eduardo Martins; Fonseca, Carlos Roberto

    2013-08-01

    Mutualistic networks are critical to biological diversity maintenance; however, their structures and functionality may be threatened by a swiftly changing world. In the Amazon, the increasing number of dams poses a large threat to biological diversity because they greatly alter and fragment the surrounding landscape. Tight coevolutionary interactions typical of tropical forests, such as the ant-myrmecophyte mutualism, where the myrmecophyte plants provide domatia nesting space to their symbiotic ants, may be jeopardized by the landscape changes caused by dams. We analyzed 31 ant-myrmecophyte mutualistic networks in undisturbed and disturbed sites surrounding Balbina, the largest Central Amazonian dam. We tested how ant-myrmecophyte networks differ among dam-induced islands, lake edges, and undisturbed forests in terms of species richness, composition, structure, and robustness (number of species remaining in the network after partner extinctions). We also tested how landscape configuration in terms of area, isolation, shape, and neighborhood alters the structure of the ant-myrmecophyte networks on islands. Ant-myrmecophytic networks were highly compartmentalized in undisturbed forests, and the compartments had few strongly connected mutualistic partners. In contrast, networks at lake edges and on islands were not compartmentalized and were negatively affected by island area and isolation in terms of species richness, density, and composition. Habitat loss and fragmentation led to coextinction cascades that contributed to the elimination of entire ant-plant compartments. Furthermore, many myrmecophytic plants in disturbed sites lost their mutualistic ant partners or were colonized by opportunistic, nonspecialized ants. Robustness of ant-myrmecophyte networks on islands was lower than robustness near lake edges and in undisturbed forest and was particularly susceptible to the extinction of plants. Beyond the immediate habitat loss caused by the building of large dams

  6. Biomass production in willows. What did we know before the energy crisis

    Energy Technology Data Exchange (ETDEWEB)

    Perttu, K L [ed.

    1984-12-01

    The biological foundations of biomass with willows originate in the experiences from basket willow husbandry. This was an established discipline in Europe in the 18th century. Problems concerning site preparation, selection of clones, planting as cuttings, spacing, weed control, rotation time, harvesting and coppicing vigour with respect to the longevity of the stand, were practically solved at the research level and already in practice. The yield potential of basket willow and willows for hoop production as well as yield figures from field experiments were quite high also according to present-day biomass willow experiments. An explanation of this could be the much higher stand densities than has been customary in current willow experiments. Although many practical questions got their answers in basket willow husbandry, open questions still remain. The basket willow era gave only little experience on willow production in peatlands; actually peatsoils were almost avoided. Knowledge of nutrient require ments and fertilization was also rather elementary. These aspects must therefore be established for biomass production. Control of weeds in the establishment phase of the willow husbandry was solved by manual work. Since this is a labour intensive method which is no longer possible, a more modern weed control needs to be developed for current husbandry. As a whole it is a task for related research to attach proper optimization of cultural techniques to suitable willow clones in order to attain and maintain as high a production level as was the case in the old basket willow husbandry. With 25 refs.

  7. Bioenergy from willow. 1995 Annual report, November 1987--December 1995

    Energy Technology Data Exchange (ETDEWEB)

    White, E.H.; Abrahamson, L.P.

    1997-07-01

    Experiments were established at Tully, New York, by the State University of New York College of Environmental Science and Forestry, in cooperation with the University of Toronto and the Ontario Ministry of Natural Resources, to assess the potential of willows for wood biomass production. Specific objectives included determining the effects of clone type, fertilization, spacing, cutting cycle, and irrigation on biomass production. Production was high, with willow clone SV1 yielding nearly 32 oven dry tons per acre (odt ac{sup -1}) with three-year harvest cycle, irrigation, and fertilization. Clone type, fertilization, spacing, cutting cycle, and irrigation all significantly affected biomass production. Willow clone-site trials planted at Massena, and Tully, NY in 1993 grew well during 1994 and 1995, but some clones in the Massena trial were severely damaged by deer browse. Several new cooperators joined the project, broadening the funding base, and enabling establishment of additional willow plantings. Willow clone-site trials were planted at Himrod, King Ferry, Somerset, and Tully, NY, during 1995. A willow cutting orchard was planted during 1995 at the NYS Department of Environmental Conservation Saratoga Tree Nursery in Saratoga, NY. Plans are to begin site preparation for a 100+ acre willow bioenergy demonstration farm in central New York, and additional clone-site trials, in 1996.

  8. Yield of tannin willows on ravine areas in the Central Forest Steppe

    Energy Technology Data Exchange (ETDEWEB)

    Sidorov, A I

    1981-01-01

    A note on the performance of 12 species of willow grown in a plantation on leached chernozem soils, to provide bark rich in tannins. The plantation was established by cuttings (25 cm long) at a spacing of 2.5 x 0.5 metres for the tree willows and 2.5 x 0.75 metres for the bush willows. Bark yields were determined at 7-8 years. The greatest yields were obtained from Salix smithiana, S. stipularis and S. acuminata: 12.0, 10.8 and 10.2 t/hectare respectively. Data on tannin yields are tabulated. Fellings for bark harvesting can be made every 5 years in plantations of bush willows and every 7 years in plantations of tree willows. The plantations can be used for 30 year with bush willows and for 50 years with tree willows.

  9. Wolf presence and increased willow consumption by Yellowstone elk: implications for trophic cascades.

    Science.gov (United States)

    Creel, Scott; Christianson, David

    2009-09-01

    Recent increases in the height and growth ring width of willow (Salix spp.) and other woody plants in the Greater Yellowstone Ecosystem (GYE) have been attributed to a behaviorally mediated trophic cascade from wolves (Canis lupus) to elk (Cervus elaphus) to willows. This hypothesis predicts that individual elk consume less willow in response to the presence of wolves, but this prediction has not been directly tested with data from elk. We collected 727 fecal samples from elk in the Gallatin Canyon portion of the GYE over three winters and used microhistological methods to quantify the proportion of willow in each sample. We then tested the effect of wolf presence on willow consumption by elk, controlling for the effects of snow conditions, sex, and habitat type. During the period of study, 8-17 wolves occupied the study area, and wolves were locally present on 49% of 260 sampling days, stratified at two-week intervals across three drainages. Over the three years combined, willow consumption was related to snow conditions, wolf presence, and a wolf X sex interaction. As expected, willow consumption increased with deeper and less penetrable snow, and this effect was strong. Contrary to expectation, willow consumption increased in the presence of wolves. As with other aspects of antipredator behavior, wolves had different effects on willow consumption by males and females. Finally, we aggregated the data to estimate winter-long mean willow consumption within each drainage; at this broader scale, willow consumption again increased as predation risk increased. In summary, willow consumption was more strongly affected by snow conditions than by the presence of wolves. Interactions between elk and willow were affected by wolves, but not as predicted by the hypothesis that wolf presence favors willow release through a reduction in the selection of willow by individual elk. If a trophic cascade is operating, our results suggest that a decline in the size of the elk

  10. Phytotoxicity of polycyclic aromatic hydrocarbons to willow trees

    DEFF Research Database (Denmark)

    Thygesen, R.S.; Trapp, Stefan

    2002-01-01

    The toxicity of PAH to willow trees (Salix alba, S. viminalis, S. viminalisx;schwerinii) was investigated. Willow cuttings were grown in PAH-saturated hydroponic solution (naphthalene NAP, phenanthrene PHEN and benzo(a)pyrene BaP). Toxicity was related to aqueous solubility and was highest for NAP...

  11. Establishment and Early Growth of Willow at Different Levels of Weed Competition and Nitrogen Fertilization

    DEFF Research Database (Denmark)

    Edelfeldt, Stina; Lundkvist, Anneli; Forkman, Johannes

    2016-01-01

    To evaluate the effects of weed competition and nitrogen fertilization on the early growth performance of willow, cuttings of the clone Tora (Salix schwerinii x S. viminalis) were planted in buckets together with model weeds (spring barley or white mustard) sown 15, 26, and 30 days after willow...... gave higher willow biomass production in willow with weeds sown after 26 or 30 days. Type of model weed had no effect on willow performance. Weed biomass and maximum shoot height were higher in weeds planted without willows compared to the willow-weed mixtures. A high nitrogen level gave more weed...... biomass when planted without willows and in the willow-weed mixture with weeds sown after 15 days. We conclude that for the given high density of willow, competition from weeds emerging soon after willow planting had strong effect on early production. Furthermore, if there is a risk of weed infestation...

  12. Phytotoxicity of polycyclic aromatic hydrocarbons to willow trees

    Energy Technology Data Exchange (ETDEWEB)

    Thygesen, R.S.; Trapp, S. [Environment and Resources DTU, Technical Univ. of Denmark, Lyngby (Denmark)

    2002-07-01

    The toxicity of PAH to willow trees (Salix alba, S. viminalis, S. viminalis x schwerinii) was investigated. Willow cuttings were grown in PAH-saturated hydroponic solution (naphthalene NAP, phenanthrene PHEN and benzo(a)pyrene BaP). Toxicity was related to aqueous solubility and was highest for NAP. PHEN did not show significant effects, except in one case. Exposure of trees to BaP showed no effect in two cases, but increased transpiration and growth in two others. High dosages of NAP were fatal for the trees, the lowest dosage significantly stimulated growth. Soil samples were taken from several PAH contaminated sites, among them gas works sites and a former sludge basin. The PAH contents ranged from 1.76 mg/kg to 1451 mg/kg. None of the soils was lethally toxic to the trees, and difference between growth in control soils and growth in PAH contaminated soils was not apparent. Growth and water use efficiency were positively, but not significantly correlated to the PAH content of the soils. Outdoor growth of willows and poplars on the former sludge basin in Valby was monitored, with willows growing faster than poplars (Populus trichocarpa). Phytotoxic effects could be observed at some willows at the Valby sludge basin, but it is not sure whether these effects can be contributed to PAH. (orig.)

  13. Environmental influence of willow coppice systems on farm land

    International Nuclear Information System (INIS)

    Ledin, S.

    1997-01-01

    As for all cultivated crops, there are numerous environmental influences when growing willows. These influences are connected with additions to the soil, management measures and changes caused by the developing crop. As a perennial crop with good root penetration into the soil, high water use and efficient nutrient uptake over a long growing season, short rotation forests with willows have an influence on the environment that differs from the influence of annual farm crops. Also the landscape is affected differently by the dense willow stand with a height of seven meters before harvest. There is usually less use of herbicides in the perennial woody crop. Due to larger amounts of litter from the willow plantation and no tillage, there is with time an increase of the humus content in the soil. In relation to this, the soil fauna, using organic material for food, prosper in the short rotation forest. Considerably more cadmium is taken up by the willows than by conventional annual crops. This could be used to clean the soil of cadmium, but more knowledge is needed for the optimisation of this procedure. Willows are usually efficient in taking up nutrients, including nitrogen, but when used as vegetation filters it is important to assess the actual ability of a stand to take up N. This ability varies considerably with the development stage of the plantation and also with site conditions. (au) 30 refs

  14. Selection of ectomycorrhizal willow genotype in phytoextraction of heavy metals.

    Science.gov (United States)

    Hrynkiewicz, Katarzyna; Baum, Christel

    2013-01-01

    Willow clones are used for the phytoextraction of heavy metals from contaminated soils and are usually mycorrhizal. The receptiveness of willow clones for mycorrhizal inoculum varies specific to genotype; however, it is unknown if this might have a significant impact on their efficiency in phytoextraction of heavy metals. Therefore, a model system with mycorrhizal and non-mycorrhizal willows of two different genotypes--one with usually stronger natural mycorrhizal colonization (Salix dasyclados), and one with lower natural mycorrhizal colonization (S. viminalis)--was investigated for its efficiency of phytoextraction of heavy metals (Cd, Pb, Cu, Zn) from contaminated soil. Inoculation with the ectomycorrhizal fungus Amanita muscaria significantly decreased the biomass of leaves of both inoculated willow clones, and increased or had no effect on the biomass of trunks and roots of S. dasyclados and S. viminalis, respectively. The concentrations of heavy metals in the biomass of S. dasyclados were in general higher than in S. viminalis irrespective of inoculation with the ectomycorrhizal fungus. Inoculation with A. muscaria significantly decreased the concentration of Cu in the trunks of both Salix taxa, but did not affected the concentrations of other heavy metals in the biomass. In conclusion, stronger receptiveness of willow clones for mycorrhizal inoculum was correlated with an increased total extraction of heavy metals from contaminated soils. Therefore, this seems to be a suitable criterion for effective willow clone selection for phytoremediation. Increased biomass production with relatively constant metal concentrations seems to be a major advantage of mycorrhizal formation of willows in phytoremediation of contaminated soils.

  15. Characterising willows for biomass and phytoremediation: growth, nitrogen and water use of 14 willow clones under different irrigation and fertilisation regimes

    International Nuclear Information System (INIS)

    Weih, Martin; Nordh, N.-E.

    2002-01-01

    Fourteen clones of willow (Salix spp.) were characterised in terms of growth, nitrogen and water-use efficiency under different irrigation and fertilisation treatments. Cuttings of willow clones, some commercially introduced and others new material, were pot-grown outdoors in Central Sweden under four experimental treatments in a full-factorial design. The experiment covered the period from bud-break until leaf abscission and the experimental conditions included two irrigation and two fertilisation regimes. The growth of the clones was evaluated in terms of relative growth rate and total biomass production of whole plants and shoots. Nitrogen (N) economy was studied by means of N productivity, N accumulation and N losses by leaf abscission. Water economy was analysed with respect to intrinsic water-use efficiency (foliar carbon isotope ratio; δ 13 C) and the capacity of leaves to retain water (relative water content). Significant differences between clones were found in nearly all parameters measured and the clones varied in the responses to the experimental treatments (clone x factor interaction effects). Thus, clone ranking often changed depending on the experimental treatment. The results are discussed with respect to clone selection for different willow applications such as biomass production and phytoremediation, and willow growth performance under different water and nutrient availabilities. The growth-physiological characterisation of young willows in the short term (several months) is regarded as a suitable approach for pre-selection of promising clones prior to extensive field evaluation

  16. Status, ecology, and conservation of the southwestern willow flycatcher

    Science.gov (United States)

    Deborah M. Finch; Scott H. Stoleson

    2000-01-01

    This publication was prepared in response to a need expressed by southwestern agencies and organizations for a comprehensive assessment of the population status, history, biology, ecology, habitats, threats, and conservation of the southwestern willow flycatcher (Empidonax traillii extimus). The southwestern willow flycatcher was federally listed as...

  17. Willow vegetation filters: Principles, results and economy

    International Nuclear Information System (INIS)

    Perttu, K.

    1996-01-01

    During recent years, it has become obvious that it is both environmentally and economically appropriate to use vegetation filters of different short rotation willows (Salix spp.) to purify water and soil. Swedish experiences of vegetation filter efficiencies have been demonstrated in several laboratory, field lysimeter, and full-scale experiments. However, there are still many questions to be answered, for example, how the uptake and allocation mechanisms of heavy metals and recalcitrant organic constituents function, or which maximum doses are possible in a particular situation without any risk of leachate losses. As far as plant nutrition is concerned, the past two decades of integrated research in Sweden have demonstrated that the willows have capacity for efficient uptake both of macro and micro nutrients, which is reflected in their high productivity. The purpose of this paper is to present some results on how vegetation filter stands of willow, irrigated with municipal wastewater, can function as purification plants, while at the same time producing fuelwood. This twofold utilization benefits both the environment and the economy. Treatment plants for wastewater purification using various types of vegetation filters have been tried in Sweden. The experiences consider both the nutrient and heavy metal uptake, and the whole process chain from establishment, cultivation and harvesting of the wastewater irrigated willow stands, to the utilization of the wood in heating plants. 33 refs, 5 tabs

  18. Competition favors elk over beaver in a riparian willow ecosystem

    Science.gov (United States)

    Baker, B.W.; Peinetti, H.R.; Coughenour, M.C.; Johnson, T.L.

    2012-01-01

    Beaver (Castor spp.) conservation requires an understanding of their complex interactions with competing herbivores. Simulation modeling offers a controlled environment to examine long-term dynamics in ecosystems driven by uncontrollable variables. We used a new version of the SAVANNA ecosystem model to investigate beaver (C. Canadensis) and elk (Cervus elapses) competition for willow (Salix spp.). We initialized the model with field data from Rocky Mountain National Park, Colorado, USA, to simulate a 4-ha riparian ecosystem containing beaver, elk, and willow. We found beaver persisted indefinitely when elk density was or = 30 elk km_2. The loss of tall willow preceded rapid beaver declines, thus willow condition may predict beaver population trajectory in natural environments. Beaver were able to persist with slightly higher elk densities if beaver alternated their use of foraging sites in a rest-rotation pattern rather than maintained continuous use. Thus, we found asymmetrical competition for willow strongly favored elk over beaver in a simulated montane ecosystem. Finally, we discuss application of the SAVANNA model and mechanisms of competition relative to beaver persistence as metapopulations, ecological resistance and alternative state models, and ecosystem regulation.

  19. Improving the water use efficiency of short rotation coppice (SRC) willows

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, W.; Bonneau, L.; Groves, S.; Armstrong, A.; Lindegard, K.

    2003-07-01

    On the premise that biofuels will make a significant contribution to the UK's renewable energy sources by the year 2010, willow short rotation coppicing is being studied. The high water requirement of willow is seen as a potential problem in the drier regions of the UK and increasing the water use efficiency and/or draught resistance would extend the areas where willow coppicing would be profitable. The first part of the project was to investigate the water use of a number of near-market varieties of willow and evaluate techniques for early drought tolerance screening in a breeding program and for this, field studies were conducted. This report gives some very early results from the preliminary study. Since DTI funding ceased before the one-season study of the three-year program was complete, the results should be regarded as tentative only. The next phase of the program will be funded by DEFRA and will include efforts to identify how a range of high-yielding willows respond to water stress.

  20. Test of aerobic TCE degradation by willows (Salix viminalis) and willows inoculated with TCE-cometabolizing strains of Burkholderia cepacia.

    Science.gov (United States)

    Clausen, Lauge Peter Westergaard; Broholm, Mette Martina; Gosewinkel, Ulrich; Trapp, Stefan

    2017-08-01

    Trichloroethylene (TCE) is a widespread soil and groundwater pollutant and clean-up is often problematic and expensive. Phytoremediation may be a cost-effective solution at some sites. This study investigates TCE degradation by willows (S. viminalis) and willows inoculated with three strains of B. cepacia (301C, PR1-31 and VM1330-pTOM), using chloride formation as an indicator of dehalogenation. Willows were grown in non-sterile, hydroponic conditions for 3 weeks in chloride-free nutrient solution spiked with TCE. TCE was added weekly due to rapid loss by volatilization. Chloride and TCE in solution were measured every 2-3 days and chloride and metabolite concentrations in plants were measured at test termination. Based on transpiration, no tree toxicity of TCE exposure was observed. However, trees grown in chloride-free solution showed severely inhibited transpiration. No or very little chloride was formed during the test, and levels of chloride in TCE-exposed trees were not elevated. Chloride concentrations in chloride containing TCE-free nutrient solution doubled within 23 days, indicating active exclusion of chloride by root cell membranes. Only traces of TCE-metabolites were detected in plant tissue. We conclude that TCE is not, or to a limited extent (less than 3%), aerobically degraded by the willow trees. The three strains of B. cepacia did not enhance TCE mineralization. Future successful application of rhizo- and phytodegradation of TCE requires measures to be taken to improve the degradation rates.

  1. Seismic risks at Elsie Lake Main Dam

    International Nuclear Information System (INIS)

    McCammon, N.R.; Momenzadeh, M.; Hawson, H.H.; Nielsen, N.M.

    1991-01-01

    The Elsie Lake dams are located on Vancouver Island in an area of high seismic risk. A safety review in 1986 indicated potential deficiencies in the earthfill main dam with respect to modern earthquake design standards. A detailed field investigation program comprising drilling and penetration tests was carried out and the results used in an assessment of seismic stability. A 0.8 m thick less dense layer in the granular shell of the dam, possibly caused by wet construction conditions, would likely liquefy in a major earthquake but sufficient residual strength would likely remain to prevent catastrophic failure. The dam shell might undergo some distortion, and an assessment was initiated to determine the requirements for reservoir drawdown following an extreme earthquake to ensure the timely lowering of the reservoir for inspection and repair. It was suggested that an adequate evacuation capability would be 25% and 50% drawdown in not more than 30 and 50 days, respectively. 9 refs., 11 figs., 1 tab

  2. SRC-willow (Salix viminalis) as a resource for flower-visiting insects

    Energy Technology Data Exchange (ETDEWEB)

    Reddersen, J. [National Environmental Research Institute, Ronde (Denmark). Dept. of Landscape Ecology

    2001-07-01

    The potential habitat value of commercial short rotation coppice (SRC)-willow plantations for flower-visiting insects was investigated. During 1998-2000, at a single typical intensive Danish farmland site, 11 Salix viminalis plantations were sampled by late April to quantify willow catkin abundance and flower sex. Mean plantation size was 1.1 ha and included one or more of clones: orm, rapp, ulv, jorr, christina and jorrun. Plot-year means of catkin abundance and of proportion of willows flowering were related to the coppicing cycle, i.e. the number of growth years since last harvest of plot ('year' 0-4). In 1998, the ground layer vegetation was sampled. Monitoring flower-visiting insects by means of line-transect counts failed due to the local scarcity of bees. At the plantation scale, flowering was discontinuous across the harvest cycle as it was totally absent in the year immediately following harvest. In successive years (1-4), individual willows flowered frequently and, occasionally, at high abundances, and catkin abundance increased with time. Within 3-4 year of harvest cycle, all plots flowered in most years with most plots exhibiting at least some flowering in any 1 year. Thus, willow catkin abundance was generally high in the total area due to: high frequency of flowering in plots, occasional high flowering abundance, plots not being harvested simultaneously and large total number of willows within plots and landscape. Similarly, flower sex ratio, and thus flower value, varied greatly between plots while variation was damped across plots. Alternative simultaneous flower resources in ground layer vegetation were few except for Dandelion. SRC willow may constitute an important resource for bees, even under the stress of the harvest cycle, and recommendations are given for improving this biodiversity aspect. (author)

  3. Phytoremediation prospects of willow stands on contaminated sediment: a field trial

    International Nuclear Information System (INIS)

    Vervaeke, P.; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F.M.G.; Lust, N.

    2003-01-01

    A field trial indicated increased degradation of mineral oil in sediments planted with willow. - Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation of organic contaminants (mineral oil and PAHs) in dredged sediment. In addition, the accumulation of heavy metals (Cd, Cu, Pb and Zn) in the biomass was determined. After 1.5 years, a significant decrease of 57% in the mineral oil concentration in the sediment planted with willow was observed. Degradation of mineral oil in sediment which was left fallow, was only 15%. The mineral oil degradation under willow was most pronounced (79%) in the root zone of the stand. In the sediment which was left fallow there was a significant reduction of the total PAH content by 32% compared with a 23% reduction in the planted sediment. The moderate and selective metal uptake, measured in this study, limits the prospects for phytoextraction of metals from dredged sediment

  4. Phytoremediation prospects of willow stands on contaminated sediment: a field trial

    Energy Technology Data Exchange (ETDEWEB)

    Vervaeke, P.; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F.M.G.; Lust, N

    2003-11-01

    A field trial indicated increased degradation of mineral oil in sediments planted with willow. - Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation of organic contaminants (mineral oil and PAHs) in dredged sediment. In addition, the accumulation of heavy metals (Cd, Cu, Pb and Zn) in the biomass was determined. After 1.5 years, a significant decrease of 57% in the mineral oil concentration in the sediment planted with willow was observed. Degradation of mineral oil in sediment which was left fallow, was only 15%. The mineral oil degradation under willow was most pronounced (79%) in the root zone of the stand. In the sediment which was left fallow there was a significant reduction of the total PAH content by 32% compared with a 23% reduction in the planted sediment. The moderate and selective metal uptake, measured in this study, limits the prospects for phytoextraction of metals from dredged sediment.

  5. Sampling procedure in a willow plantation for chemical elements important for biomass combustion quality

    DEFF Research Database (Denmark)

    Liu, Na; Nielsen, Henrik Kofoed; Jørgensen, Uffe

    2015-01-01

    clone ‘Tordis’, and to reveal the relationship between sampling position, shoot diameters, and distribution of elements. Five Tordis willow shoots were cut into 10–50 cm sections from base to top. The ash content and concentration of twelve elements (Al, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, P, Si, and Zn......Willow (Salix spp.) is expected to contribute significantly to the woody bioenergy system in the future, so more information on how to sample the quality of the willow biomass is needed. The objectives of this study were to investigate the spatial variation of elements within shoots of a willow......) in each section were determined. The results showed large spatial variation in the distribution of most elements along the length of the willow shoots. Concentrations of elements in 2-year old shoots of the willow clone Tordis were fairly stable within the range of 100–285 cm above ground and resembled...

  6. Coastal Energy Corporation, Willow Springs, MO

    Science.gov (United States)

    notice of a proposed Administrative Penalty Assessment against Coastal Energy Corporation, located at 232 Burnham Road, Willow Springs, Missouri, for alleged violations at the facility located at or near that facility.

  7. Phytoremediation prospects of willow stands on contaminated sediment : A field trial

    NARCIS (Netherlands)

    Vervaeke, P; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F. M.G.; Lust, N

    2003-01-01

    Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation

  8. Flood effects provide evidence of an alternate stable state from dam management on the Upper Missouri River

    Science.gov (United States)

    Skalak, Katherine; Benthem, Adam J.; Hupp, Cliff R.; Schenk, Edward R.; Galloway, Joel M.; Nustad, Rochelle A.

    2017-01-01

    We examine how historic flooding in 2011 affected the geomorphic adjustments created by dam regulation along the approximately 120 km free flowing reach of the Upper Missouri River bounded upstream by the Garrison Dam (1953) and downstream by Lake Oahe Reservoir (1959) near the City of Bismarck, ND, USA. The largest flood since dam regulation occurred in 2011. Flood releases from the Garrison Dam began in May 2011 and lasted until October, peaking with a flow of more than 4200 m3 s−1. Channel cross-section data and aerial imagery before and after the flood were compared with historic rates of channel change to assess the relative impact of the flood on the river morphology. Results indicate that the 2011 flood maintained trends in island area with the loss of islands in the reach just below the dam and an increase in island area downstream. Channel capacity changes varied along the Garrison Segment as a result of the flood. The thalweg, which has been stable since the mid-1970s, did not migrate. And channel morphology, as defined by a newly developed shoaling metric, which quantifies the degree of channel braiding, indicates significant longitudinal variability in response to the flood. These results show that the 2011 flood exacerbates some geomorphic trends caused by the dam while reversing others. We conclude that the presence of dams has created an alternate geomorphic and related ecological stable state, which does not revert towards pre-dam conditions in response to the flood of record. This suggests that management of sediment transport dynamics as well as flow modification is necessary to restore the Garrison Segment of the Upper Missouri River towards pre-dam conditions and help create or maintain habitat for endangered species. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  9. Dam! Dam! Dam!

    International Nuclear Information System (INIS)

    McCully, P.

    1997-01-01

    The author of ''Silenced Rivers'' a book questioning the desirability of dam building and hydroelectric power generation argues the main themes of his book in this paper. Despite being hailed by politicians as good solutions to power generation problems, and enthusiastically pursued in China, the U.S.A., the former Soviet Union, India and Japan, dams have far-reaching ecological and human consequences. The ecosystems lost to flooding, and the agricultural land use lost, the human cost in terms of homes and employment lost to reservoirs, disease from water-borne infections such as malaria, and the hazards of dams overflowing or breaking are all factors which are against the case for dam construction. The author argues the hydroelectric power may be renewable, but the social, agricultural and ecological costs are too high to justify it as a method of first choice. (UK)

  10. The potential of willow for remediation of heavy metal polluted calcareous urban soils

    International Nuclear Information System (INIS)

    Jensen, Julie K.; Holm, Peter E.; Nejrup, Jens; Larsen, Morten B.; Borggaard, Ole K.

    2009-01-01

    Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber uptakes. Despite high concentrations of cadmium (≥80 mg/kg) and zinc (≥3000 mg/kg) in leaves of willow grown on strongly polluted soil with up to 18 mg Cd/kg, 1400 mg Cu/kg, 500 mg Pb/kg and 3300 mg Zn/kg, it is unsuited on strongly polluted soils because of poor growth. However, willow proved promising on moderately polluted soils (2.5 mg Cd/kg and 400 mg Zn/kg), where it extracted 0.13% of total Cd and 0.29% of the total Zn per year probably representing the most mobile fraction. Cu and Pb are strongly fixed in calcareous soils. - Willow is suited for remediation of moderately heavy metal polluted calcareous soils

  11. Fertilization of SRC willow. II

    DEFF Research Database (Denmark)

    Sevel, L; Ingerslev, Morten; Nord-Larsen, Thomas

    2014-01-01

    impacts of different doses of mineral fertilizer, manure and sewage sludge in a commercially grown SRC willow stand. We examined macro nutrient and heavy metal leaching rates and calculated element balances to evaluate the environmental impact. Growth responses were reported in a former paper (Sevel et al...

  12. Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

    Directory of Open Access Journals (Sweden)

    Maíra Benchimol

    Full Text Available Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

  13. Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

    Science.gov (United States)

    Benchimol, Maíra; Peres, Carlos A

    2015-01-01

    Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species) responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

  14. Downstream ecological effects of dams: A geomorphic perspective

    International Nuclear Information System (INIS)

    Ligon, F.K.; Dietrich, W.E.; Trush, W.J.

    1995-01-01

    The damming of a river changes the flow of water, sediment, nutrients, energy, and biota, interrupting and altering most of a river's ecological processes. This article discusses the importance of geomorphological analysis in river conservation and management. To illustrate how subtle geomorphological adjustments may profoundly influence the ecological relationships downstream from dames, three case studies are presented. Then a geomorphically based approach for assessing and possibly mitigating some of the environmental effects of dams by tailoring dam designed and operation is outlined. The cases are as follows: channel simplification and salmon decline on the McKenzie River in Oregon; Channel incision and reduced floodplain inundation on the Oconee river in Georgia; Increased stability of a braided river in New Zealand's south island. 41 refs., 10 figs., 1 tab

  15. Irrigation water quality influences heavy metal uptake by willows in biosolids.

    Science.gov (United States)

    Laidlaw, W Scott; Baker, Alan J M; Gregory, David; Arndt, Stefan K

    2015-05-15

    Phytoextraction is an effective method to remediate heavy metal contaminated landscapes but is often applied for single metal contaminants. Plants used for phytoextraction may not always be able to grow in drier environments without irrigation. This study investigated if willows (Salix x reichardtii A. Kerner) can be used for phytoextraction of multiple metals in biosolids, an end-product of the wastewater treatment process, and if irrigation with reclaimed and freshwater influences the extraction process. A plantation of willows was established directly onto a tilled stockpile of metal-contaminated biosolids and irrigated with slightly saline reclaimed water (EC ∼2 dS/cm) at a wastewater processing plant in Victoria, Australia. Biomass was harvested annually and analysed for heavy metal content. Phytoextraction of cadmium, copper, nickel and zinc was benchmarked against freshwater irrigated willows. The minimum irrigation rate of 700 mm per growing season was sufficient for willows to grow and extract metals. Increasing irrigation rates produced no differences in total biomass and also no differences in the extraction of heavy metals. The reclaimed water reduced both the salinity and the acidity of the biosolids significantly within the first 12 months after irrigation commenced and after three seasons the salinity of the biosolids had dropped to metal extraction. Reclaimed water irrigation reduced the biosolid pH and this was associated with reductions of the extraction of Ni and Zn, it did not influence the extraction of Cu and enhanced the phytoextraction of Cd, which was probably related to the high chloride content of the reclaimed water. Our results demonstrate that flood-irrigation with reclaimed water was a successful treatment to grow willows in a dry climate. However, the reclaimed water can also change biosolids properties, which will influence the effectiveness of willows to extract different metals. Copyright © 2015 Elsevier Ltd. All rights

  16. Treatment of log yard run-off by irrigation of grass and willows

    International Nuclear Information System (INIS)

    Jonsson, Maria; Dimitriou, Ioannis; Aronsson, Paer; Elowson, Torbjoern

    2006-01-01

    Log yard run-off is a potential environmental risk, among other things because it creates an oxygen deficiency in receiving watercourses. This study was conducted to investigate the purification efficiency of soil-plant systems with couchgrass (Elymus repens) and willows (Salix sp.) when intensively irrigated with run-off from an open sprinkling system at a Norway spruce (Picea abies) log yard. The purification efficiency was determined both at the field scale (couchgrass) and in 68-L lysimeters (couchgrass and willows). Groundwater in the field and drainage water from the lysimeters were analysed for Total Organic Carbon (TOC), distillable phenols, total P, and total N. Retention of TOC, phenols and P occurred but no difference between couchgrass and willows was observed. The system had better purification capacity at the field scale than in the lysimeters. -- By irrigating willow and couchgrass soil-plant systems with log yard run-off water, TOC, phenols, and phosphorus were reduced with 35% to 96% in the water

  17. Uptake, metabolism, accumulation and toxicity of cyanide in willow trees

    DEFF Research Database (Denmark)

    Larsen, Morten; Ucisik, Ahmed Süheyl; Trapp, Stefan

    2005-01-01

    Chemicals taken up into plants may be accumulated so leading to toxic effects. Uptake and phytotoxicity of free cyanide was determined with the willow-tree transpiration test. Willow sets were grown in sand and irrigated with varying levels of cyanide (CN). Toxicity was determined by measuring...... transpiration. At CN concentrations below 10 mg/L, no toxic effects were observed. At 20 mg/L, transpiration was reduced to approximately 50% after 96 h. With 30, 40 and 50 mg/L, the transpiration decreased with a similar rate to cyanide in plant...... tissue was observed at 40 and 50 mg/L. The kinetics of metabolism of cyanide by roots, stems and leaves of willows was determined by the closed-bottle metabolism test. The Michaelis−Menten parameters vmax and KM (maximal metabolic velocity and half-saturation constant, respectively) were determined...

  18. Ice-dammed lateral lake and epishelf lake insights into Holocene dynamics of Marguerite Trough Ice Stream and George VI Ice Shelf, Alexander Island, Antarctic Peninsula

    Science.gov (United States)

    Davies, Bethan J.; Hambrey, Michael J.; Glasser, Neil F.; Holt, Tom; Rodés, Angél; Smellie, John L.; Carrivick, Jonathan L.; Blockley, Simon P. E.

    2017-12-01

    We present new data regarding the past dynamics of Marguerite Trough Ice Stream, George VI Ice Shelf and valley glaciers from Ablation Point Massif on Alexander Island, Antarctic Peninsula. This ice-free oasis preserves a geological record of ice stream lateral moraines, ice-dammed lakes, ice-shelf moraines and valley glacier moraines, which we dated using cosmogenic nuclide ages. We provide one of the first detailed sediment-landform assemblage descriptions of epishelf lake shorelines. Marguerite Trough Ice Stream imprinted lateral moraines against eastern Alexander Island at 120 m at Ablation Point Massif. During deglaciation, lateral lakes formed in the Ablation and Moutonnée valleys, dammed against the ice stream in George VI Sound. Exposure ages from boulders on these shorelines yielded ages of 13.9 to 9.7 ka. Following recession of the ice stream, George VI Ice Shelf formed in George VI Sound. An epishelf lake formed at 15-20 m asl in Ablation and Moutonnée valleys, dated from 9.4 to 4.6 ka, suggesting that the lake was stable and persistent for some 5000 years. Lake-level lowering occurred after this, with the lake level at 12 m at 3.1 ± 0.4 ka and at 5 m asl today. A readvance of the valley glaciers on Alexander Island at 4.4 ± 0.7 ka is recorded by valley glacier moraines overlying epishelf lake sediments. We speculate that the glacier readvance, which occurred during a period of warmth, may have been caused by a dynamic response of the glaciers to a lowering in surface elevation of George VI Ice Shelf.

  19. Treatment of landfill leachate by irrigation of willow coppice - Plant response and treatment efficiency

    International Nuclear Information System (INIS)

    Aronsson, Paer; Dahlin, Torleif; Dimitriou, Ioannis

    2010-01-01

    Landfill leachates usually need to be treated before discharged, and using soil-plant systems for this has gained substantial interest in Sweden and in the UK. A three-year field study was conducted in central Sweden to quantify plant response, treatment efficiency and impact on groundwater quality of landfill leachate irrigation of short-rotation willow coppice (Salix). Two willow varieties were tested and four irrigation regimes in sixteen 400-m 2 plots. The willow plants did not react negatively, despite very high annual loads of nitrogen (≤2160 kg N/ha), chloride (≤8600 kg Cl/ha) and other elements. Mean annual growth was 1.5, 9.8 and 12.6 tonnes DM/ha during years 1-3. For one of two willow varieties tested, relative leaf length accurately predicted growth rate. Irrigation resulted in elevated groundwater concentrations of all elements applied. Treatment efficiency varied considerably for different elements, but was adequate when moderate loads were applied. - Short-rotation willow coppice was successfully used for treating a strong landfill leachate in central Sweden over three years.

  20. The potential of willow for remediation of heavy metal polluted calcareous urban soils

    DEFF Research Database (Denmark)

    Jensen, J K; Holm, P E; Nejrup, J

    2009-01-01

    Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber...

  1. Willow trees from heavy metals phytoextraction as energy crops

    International Nuclear Information System (INIS)

    Šyc, Michal; Pohořelý, Michael; Kameníková, Petra; Habart, Jan; Svoboda, Karel; Punčochář, Miroslav

    2012-01-01

    Phytoextraction ability of some fast growing plant species leads to the idea of connecting biomass production with soil remediation of contaminated industrial zones and regions. This biomass will contain significant amount of heavy metals and its energetic utilization has to be considered carefully to minimize negative environmental impacts. This study was focused on potential disposal methods of willow trees contaminated by heavy metals (Cd, Cu, Pb, Zn) with the emphasis on energetic utilization of biomass. Composting seems to be suitable pre-treatment method resulting in decrease of heavy metals leachability and biomass weight reduction. The possibility of willow trees application for energetic purposes was investigated and consequently incineration tests of willow trees samples in fluidized bed reactor were realized. Distribution of selected heavy metals in different ash fractions and treatment methods of produced ashes were studied as well. -- Highlights: ► Composting is an appropriate pre-treatment method for phytoextraction crops. ► Fluidized bed combustion is suitable disposal method of phytoextraction crops. ► Ashes from phytoextraction crops combustion cannot be used as fertilizers.

  2. Erratum to: Fertilization of SRC Willow

    DEFF Research Database (Denmark)

    Sevel, L; Ingerslev, Morten; Nord-Larsen, Thomas

    2014-01-01

    impacts of different doses of mineral fertilizer, manure and sewage sludge in a commercially grown SRC willow stand. We examined macro nutrient and heavy metal leaching rates and calculated element balances to evaluate the environmental impact. Growth responses were reported in a former paper (Sevel et al...

  3. Willow Browse Survey 2016 : Biological Summary Report

    Data.gov (United States)

    Department of the Interior — Browse pressure by ungulate species, primarily elk, is known to have a negative impact on the health of willow stands. On Baca and Alamosa NWR’s, it has been noticed...

  4. Willow Browse Survey 2015 : Biological Summary Report

    Data.gov (United States)

    Department of the Interior — Browse pressure by ungulate species, primarily elk, is known to have a negative impact on the health of willow stands. On Baca and Alamosa NWR’s, it has been noticed...

  5. Willow as fuel for district heating. Experiences from test combustion; Energipil som braendsel til fjernvarme - Erfaringsindsamling fra testfyringer

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Joergen

    2012-10-15

    The project has been a study of the fuel characteristics of willow chips. The study was carried out on Trustrup-Lyngby Heating Plant and Assens District Heating Plant in the period 2011-12. Operating experiences were collected from the two plants. Furthermore, yield and crop data were collected from suppliers of willow chips to Assens District Heating Plant, and the analysis of particle size distribution of the willow chips is carried out. The collected data on yield and particle size distribution are compared with results from previous studies. The project has shown that willow chips generally are a suitable and attractive fuel in wood-fired heat and power plants. The plants are very aware of quality of willow chips and want chips with coarse structure. Furthermore, there is the wish that water content of willow chips are on par with the moisture content of wood chips, i.e. around 30-40%; woodchips are the vast majority of the chips used in the plants. Wood chips produced from fresh willow shoots with chopper will typically have a moisture content of 50-60 %. Such ''wet'' chips will of some plants be deselected during winter, where there is a requirement of safe and high boiler output. Other plants will simply mix the ''wet'' willow chips with other, drier types of chips and can use it almost all the year. If the willow shoots are harvested as branches, which subsequently are allowed to dry for a period before chipping, willow chips can be produced with a moisture content that is in line with what is typical in wood chips. Analysis of particle size distribution shows that willow chips harvested with a cutting machine usually can meet the requirements for quality classes ''fine'', ''medium'' and ''coarse''. An account of the harvested yields of willow among the growers who supplied willow chips to Assens Heating Plant, showed a relatively low yield of 5.1 tonnes dry

  6. Comparison of willow and sunflower for uranium phytoextraction induced by citric acid

    International Nuclear Information System (INIS)

    Jan Mihalik; National Radiation Protection Institute, Prague; CZU, FAPPZ, Prague; Pavel Tlustos; Jirina Szakova

    2010-01-01

    This study deals with an efficiency of a low dose of citric acid soil application on phytoextraction of uranium. Willow (Salix spp.) and sunflower (Helianthus annus L.) were tested in this experiment with contaminated soil. The enhancing of uranium bioaccumulation was confirmed, but in contrast to previous studies, the highest quantity of uranium was accumulated in leaves. After 5 weeks of citric acid treatment, willow was more efficient in the uptake and translocation of uranium than sunflower. The transfer coefficient calculated for leaves increased from 0.033 (control) to 0.74, or 0.56 after five doses of 5 mmol of citric acid per 1 kg of soil for willow or sunflower, respectively. The uptake characterized by the total U content achieved 88 and 108 mg kg -1 in relation to the above ground parts of sunflower and willow, respectively. Even though both plants accumulated U in their above ground parts in significant rate, they employed diverse ways to achieve it. At the end of the treatment, the physiological condition of the plants enabled us to continue this method. (author)

  7. Puente Willow Creek en Monterrey, California

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1965-09-01

    Full Text Available Of the 10 awards given every year by the Prestressed Concrete Institute for the most outstanding prestressed concrete projects, two have been awarded in California this year, one of them to the Willow Creek bridge, near Monterrey. The prestressed, double T girders of this bridge were made at a workshop, a great distance from the bridge site. These are 24 m long, 1.35 m high, and are stabilized by transversal diaphragms, 20 cm in thickness. The table deck is of reinforced concrete, being 8.85 m wide and 20 cm thick. The structure is straightforward, slender, and adapts itself pleasantly to the background. It has seven spans and crosses over a secondary road, in addition to bridging the Willow stream. The supporting piles are hollow, of rectangular cross section, and over them a cross beam carries the five girders and the deck itself. The end abutments consist of vertical reinforced concrete walls, and supporting, soil filled, structures. The above information was supplied by the California Road Department.De los diez premios que anualmente concede el Prestressed Concrete Institute para las obras de hormigón pretensado más notables, dos han correspondido a California y uno de ellos al puente de Willow Creek, situado en la región de Monterrey. Las vigas de hormigón pretensado, con sección en forma de doble T, se prefabricaron en un taller situado a gran distancia del puente. Tienen 24 m de longitud y 1,35 m de canto, estando arriostradas con diafragmas transversales de 20 cm de espesor. La losa del tablero, de hormigón armado, tiene 8,85 m de anchura y 20 cm de espesor. La estructura es sencilla, esbelta y armoniza perfectamente con el paisaje que la circunda. Tiene siete tramos y salva un paso inferior secundario y el arroyo Willow. Los soportes, se apoyan sobre pilotes, algunos de gran altura; son huecos, de sección rectangular y terminan en una cruceta que sirve de sostén a las cinco vigas que soportan la losa del tablero. Los estribos

  8. Machinery management data for willow harvest with a bio-baler

    Energy Technology Data Exchange (ETDEWEB)

    Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada); Hebert, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Robert, F.S. [Laval Univ., Quebec City, PQ (Canada). Sols et environnement

    2010-07-01

    Willow harvested in 2-to-3-year rotations has been touted as a reliable source of biomass. A newly designed harvester based on a round baler was developed in 2006. The third generation biobaler was evaluated in 2009 at 2 willow plantations in Quebec. The first site at Godmanchester was a three-year old regrowth with an estimated 52,000 stems/ha of large diameter willow. The biobaler with a flail cutter harvested three plots totalling 4,136 m{sup 2}. Total harvested biomass was 10.36 t DM in 42 bales. The harvest rate averaged 29 bale/h with an average bale size of 1.22 m wide by 1.30 m in diameter. Diesel fuel consumption averaged 0.81 L/bale. Measured losses averaged 11 per cent of the yield. The second site at Saint-Roch-del'Achigan was a two-year old growth with an estimated 49,000 stems/ha of large stem willow. The biobaler harvested seven plots totalling 15,740 m{sup 2}. Total harvest was 30.70 t DM in 148 bales. The first 14 bales were harvested with a saw blade header. All other bales were harvested with the flail cutter at a faster rate. Bale density averaged 129 kg DM/m{sup 3}. Fuel consumption averaged 0.72 L/bale. Losses averaged 20 per cent of the yield with the saw blade header.

  9. Willow on Yellowstone's northern range: evidence for a trophic cascade?

    Science.gov (United States)

    Beyer, Hawthorne L; Merrill, Evelyn H; Varley, Nathan; Boyce, Mark S

    2007-09-01

    Reintroduction of wolves (Canis lupus) to Yellowstone National Park in 1995-1996 has been argued to promote a trophic cascade by altering elk (Cervus elaphus) density, habitat-selection patterns, and behavior that, in turn, could lead to changes within the plant communities used by elk. We sampled two species of willow (Salix boothii and S. geyeriana) on the northern winter range to determine whether (1) there was quantitative evidence of increased willow growth following wolf reintroduction, (2) browsing by elk affected willow growth, and (3) any increase in growth observed was greater than that expected by climatic and hydrological factors alone, thereby indicating a trophic cascade caused by wolves. Using stem sectioning techniques to quantify historical growth patterns we found an approximately twofold increase in stem growth-ring area following wolf reintroduction for both species of willow. This increase could not be explained by climate and hydrological factors alone; the presence of wolves on the landscape was a significant predictor of stem growth above and beyond these abiotic factors. Growth-ring area was positively correlated with the previous year's ring area and negatively correlated with the percentage of twigs browsed from the stem during the winter preceding growth, indicating that elk browse impeded stem growth. Our results are consistent with the hypothesis of a behaviorally mediated trophic cascade on Yellowstone's northern winter range following wolf reintroduction. We suggest that the community-altering effects of wolf restoration are an endorsement of ecological-process management in Yellowstone National Park.

  10. Simulation modeling to understand how selective foraging by beaver can drive the structure and function of a willow community

    Science.gov (United States)

    Peinetti, H.R.; Baker, B.W.; Coughenour, M.B.

    2009-01-01

    Beaver-willow (Castor-Salix) communities are a unique and vital component of healthy wetlands throughout the Holarctic region. Beaver selectively forage willow to provide fresh food, stored winter food, and construction material. The effects of this complex foraging behavior on the structure and function of willow communities is poorly understood. Simulation modeling may help ecologists understand these complex interactions. In this study, a modified version of the SAVANNA ecosystem model was developed to better understand how beaver foraging affects the structure and function of a willow community in a simulated riparian ecosystem in Rocky Mountain National Park, Colorado (RMNP). The model represents willow in terms of plant and stem dynamics and beaver foraging in terms of the quantity and quality of stems cut to meet the energetic and life history requirements of beaver. Given a site where all stems were equally available, the model suggested a simulated beaver family of 2 adults, 2 yearlings, and 2 kits required a minimum of 4 ha of willow (containing about10 stems m-2) to persist in a steady-state condition. Beaver created a willow community where the annual net primary productivity (ANPP) was 2 times higher and plant architecture was more diverse than the willow community without beaver. Beaver foraging created a plant architecture dominated by medium size willow plants, which likely explains how beaver can increase ANPP. Long-term simulations suggested that woody biomass stabilized at similar values even though availability differed greatly at initial condition. Simulations also suggested that willow ANPP increased across a range of beaver densities until beaver became food limited. Thus, selective foraging by beaver increased productivity, decreased biomass, and increased structural heterogeneity in a simulated willow community.

  11. Life cycle assessment of a willow bioenergy cropping system

    International Nuclear Information System (INIS)

    Heller, M.C.; Keoleian, G.A.; Volk, Timothy A.

    2003-01-01

    The environmental performance of willow biomass crop production systems in New York (NY) is analyzed using life cycle assessment (LCA) methodology. The base-case, which represents current practices in NY, produces 55 units of biomass energy per unit of fossil energy consumed over the biomass crop's 23-year lifetime. Inorganic nitrogen fertilizer inputs have a strong influence on overall system performance, accounting for 37% of the non-renewable fossil energy input into the system. Net energy ratio varies from 58 to below 40 as a function of fertilizer application rate, but application rate also has implications on the system nutrient balance. Substituting inorganic N fertilizer with sewage sludge biosolids increases the net energy ratio of the willow biomass crop production system by more than 40%. While CO 2 emitted in combusting dedicated biomass is balanced by CO 2 adsorbed in the growing biomass, production processes contribute to the system's net global warming potential. Taking into account direct and indirect fuel use, N 2 O emissions from applied fertilizer and leaf litter, and carbon sequestration in below ground biomass and soil carbon, the net greenhouse gas emissions total 0.68 g CO 2 eq. MJ biomassproduced -1 . Site specific parameters such as soil carbon sequestration could easily offset these emissions resulting in a net reduction of greenhouse gases. Assuming reasonable biomass transportation distance and energy conversion efficiencies, this study implies that generating electricity from willow biomass crops could produce 11 units of electricity per unit of fossil energy consumed. Results form the LCA support the assertion that willow biomass crops are sustainable from an energy balance perspective and contribute additional environmental benefits

  12. Mortality of radio collared willow ptarmigan in Smoela wind-power plant

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Hans Chr.; Broeseth, Henrik; Nilsen, Erlend B.; Sandercock, Brett K.; Bevanger, Kjetil

    2011-07-01

    Full text: In the project Pre- and post-construction studies of conflicts between birds and wind turbines in coastal Norway (BirdWind), Smoela willow ptarmigan (Lagopus lagopus variegatus) has been one of the species studied. This sub-species represent gallinaceous birds, known to be bad flyers susceptible to collide with artificial structures, e.g. power lines. However, the possible impact of a wind-power plant on survival and behaviour in a willow ptarmigan population was unknown. The objectives of the study were therefore rather wide; to study direct and indirect effects of wind turbines on willow ptarmigan behaviour, habitat selection, reproduction and survival in areas where wind-power plants are established. To collect data on habitat selection, movements, collision risks, avoidance behaviour, survival and general population dynamic parameters, willow ptarmigan were radio-tagged in 2008-2010, using traditional VHF-transmitters (Holohill) with mortality switch, necklace mount, 12 g, lasting for approximately 24 months. Due to low population density and only occasional snow cover, a method using strong lights, dipnet and car was used to catch birds. In total, 34 willow ptarmigan were caught (19 males and 15 females). All birds were caught inside the wind-power plant area (WPA). The birds were radio-tracked at irregular intervals and almost all birds, when found, was located within the WPA. All carcasses of dead birds were examined. When possible, cause of death was determined as; predation (raptor), collision, unknown, other. In total, 28 of the radio-tagged birds have died since January 2008. A Kaplan-Meier analysis of cumulative survival rates, show an exceptionally low survival (<30%). Unlike other willow ptarmigan populations most of the mortality takes place during winter, from December throughout March. Although a thorough analysis of mortality causes has yet not been carried out, a majority of the birds have probably been killed by avian predators and to

  13. Tailings dams from the perspective of conventional dam engineering

    International Nuclear Information System (INIS)

    Szymanski, M.B.

    1999-01-01

    A guideline intended for conventional dams such as hydroelectric, water supply, flood control, or irrigation is used sometimes for evaluating the safety of a tailings dam. Differences between tailings dams and conventional dams are often substantial and, as such, should not be overlooked when applying the techniques or safety requirements of conventional dam engineering to tailings dams. Having a dam safety evaluation program developed specifically for tailings dams is essential, if only to reduce the chance of potential errors or omissions that might occur when relying on conventional dam engineering practice. This is not to deny the merits of using the Canadian Dam Safety Association Guidelines (CDSA) and similar conventional dam guidelines for evaluating the safety of tailings dams. Rather it is intended as a warning, and as a rationale underlying basic requirement of tailings dam emgineering: specific experience in tailings dams is essential when applying conventional dam engineering practice. A discussion is included that focuses on the more remarkable tailings dam safety practics. It is not addressed to a technical publications intended for such dams, or significantly different so that the use of conventional dam engineering practice would not be appropriate. The CDSA Guidelines were recently revised to include tailings dams. But incorporating tailings dams into the 1999 revision of the CDSA Guidelines is a first step only - further revision is necessary with respect to tailings dams. 11 refs., 2 tabs

  14. Removal of 4-chlorobenzoic acid from spiked hydroponic solution by willow trees (Salix viminalis)

    DEFF Research Database (Denmark)

    Deavers, K.; Macek, T.; Karlson, U.

    2010-01-01

    . Methods The removal of 4-CBA by willow trees was investigated with intact, septic willow trees growing in hydroponic solution and with sterile cell suspensions at concentrations of 5 mg/L and 50 mg/L 4-CBA. Nutrient solutions with different levels of ammonium and nitrate were prepared to achieve different...

  15. The development of short-rotation willow in the northeastern United States for bioenergy and bioproducts, agroforestry and phytoremediation

    International Nuclear Information System (INIS)

    Volk, T.A.; Abrahamson, L.P.; Nowak, C.A.; White, E.H.; Smart, L.B.; Tharakan, P.J.

    2006-01-01

    Research on willow (Salix spp.) as a locally produced, renewable feedstock for bioenergy and bioproducts began in New York in the mid-1980s in response to growing concerns about environmental impacts associated with fossil fuels and declining rural economies. Simultaneous and integrated activities-including research, large-scale demonstrations, outreach and education, and market development-were initiated in the mid-1990s to facilitate the commercialization of willow biomass crops. Despite technological viability and associated environmental and local economic benefits, the high price of willow biomass relative to coal has been a barrier to wide-scale deployment of this system. The cost of willow biomass is currently $3.00GJ -1 ($57.30odt -1 ) compared to $1.40-1.90GJ -1 for coal. Yield improvements from traditional breeding efforts and increases in harvesting efficiency that are currently being realized promise to reduce the price differential. Recent policy changes at the federal level, including the provision to harvest bioenergy crops from Conservation Reserve Program (CRP) land and a closed-loop biomass tax credit, and state-level initiatives such as Renewable Portfolio Standards (RPS) will help to further reduce the difference and foster markets for willow biomass. Years of work on willow biomass crop research and demonstration projects have increased our understanding of the biology, ecophysiology and management of willow biomass crops. Using an adaptive management model, this information has led to the deployment of willow for other applications such as phytoremediation, living snow fences, and riparian buffers across the northeastern US. (author)

  16. Foraging intention affects whether willow tits call to attract members of mixed-species flocks.

    Science.gov (United States)

    Suzuki, Toshitaka N; Kutsukake, Nobuyuki

    2017-06-01

    Understanding how individual behaviour influences the spatial and temporal distribution of other species is necessary to resolve the complex structure of species assemblages. Mixed-species bird flocks provide an ideal opportunity to investigate this issue, because members of the flocks are involved in a variety of behavioural interactions between species. Willow tits ( Poecile montanus ) often produce loud calls when visiting a new foraging patch to recruit other members of mixed-species flocks. The costs and benefits of flocking would differ with individual foraging behaviours (i.e. immediate consumption or caching); thus, willow tits may adjust the production of loud calls according to their foraging intention. In this study, we investigated the link between foraging decisions and calling behaviour in willow tits and tested its influence on the temporal cohesion with members of mixed-species flocks. Observations at experimental foraging patches showed that willow tits produced more calls when they consumed food items compared with when they cached them. Playback experiments revealed that these calls attracted flock members and helped to maintain their presence at foraging patches. Thus, willow tits adjusted calling behaviour according to their foraging intention, thereby coordinating the associations with members of mixed-species flocks. Our findings demonstrate the influence of individual decision-making on temporal cohesion with other species and highlight the importance of interspecific communication in mixed-species flocking dynamics.

  17. Environmental applications of poplars and willows

    Science.gov (United States)

    J.G. Isebrands; P. Aronsson; M. Carlson; R. Ceulemans; M. Coleman; N. Dickinson; J. Dimitriou; S. Doty; E. Gardiner; K. Heinsoo; J.D. Johnson; Y.B. Koo; J. Kort; J. Kuzovkina; L. Licht; A.R. McCracken; I. McIvor; P. Mertens; K. Perttu; D. Riddell-Black; B. Robins; G. Scarascia-Mugnozza; W.R. Schroeder; John Stanturf; T.A. Volk; M. Weih

    2014-01-01

    Poplars and willows have been planted for environmental purposes for millennia. There are reports that poplars were planted to improve the human environment 4000 years ago in the third dynasty of Ur, for streamside stabilization 2000 years ago in what is now the south-western USA by native North Americans and for urban amenities by the early Chinese dynasties (see...

  18. Community outreach and education: key components of the Salix consortium's willow biomass project

    International Nuclear Information System (INIS)

    Volk, T.A.; Edick, S.; Brown, S.; Downing, M.

    1999-01-01

    This project facilitates the commercialization of willow biomass crops as a locally grown source of renewable energy. The challenge is to simultaneously optimize production and utilization technology, develop farmer interest and crop acreage, and establish stable and reliable markets. The participation of farmers and landowners, businesses, and local and regional governments in the process is essential for success. A three-phased approach elicits this participation: focused outreach and education, active involvement of potential producers of willow biomass crops, and the development of a user-friendly economic and business model that can be used by a variety of stakeholders. Barriers to commercialization have been identified, such as misconceptions about the production system and crop, assurances of a stable and reliable market for the material, and indications that the equipment and infrastructure to grow and process willow biomass crops are in place. Outreach efforts have specifically addressed these issues. As a result target audiences' responses have changed from passive observation to inquiries and suggestions for active participation. This shift represents a significant step towards the goal of making willow biomass crops a viable source of locally produced fuel. (author)

  19. The potential of willow and poplar plantations as carbon sinks in Sweden

    International Nuclear Information System (INIS)

    Rytter, Rose-Marie

    2012-01-01

    A large share, estimated at 12–25%, of the annual anthropogenic greenhouse gas emissions is attributed to global deforestation. Increasing the forested areas therefore has a positive impact on carbon (C) sequestration and mitigation of high atmospheric CO 2 concentrations. Fast-growing species, such as willow and poplar, are of high interest as producers of biomass for fuel, but also as C sinks. The present study estimated the rate of C sequestration in biomass and soil in willow and poplar plantations. Calculations were based on above- and below-ground biomass production data from field experiments, including fine root turnover, litter decomposition rates, and production levels from commercial plantations. Accumulation of C in woody biomass, above and below ground, was estimated at 76.6–80.1 Mg C ha −1 and accumulation of C in the soil at 9.0–10.3 Mg C ha −1 over the first 20–22 years. The average rates of C sequestration were 3.5–4.0 Mg C ha −1 yr −1 in woody biomass, and 0.4–0.5 Mg C ha −1 yr −1 in the soil. If 400,000 ha of abandoned arable land in Sweden were planted with willow and poplar, about 1.5 Tg C would be sequestered annually in woody biomass and 0.2 Tg C in soils. This would be nearly one tenth of the annual anthropogenic emissions of C in Sweden today. These calculations show the potential of fast-growing plantations on arable land to mitigate the effect of high CO 2 concentrations over a short time span. Knowledge gaps were found during the calculation process and future research areas were suggested. -- Highlights: ► Poplars and willows as producers of biomass for fuel and as C sinks. ► Calculation of C sequestration rates in biomass and soil in willow and poplar plantations. ► Increasing forested areas has positive impact on high CO 2 levels. ► Willow and poplar plantations on arable land mitigate anthropogenic CO 2 emissions.

  20. Wood biomass: The potential of willow

    International Nuclear Information System (INIS)

    White, E.H.; Abrahamson, L.P.

    1991-10-01

    Experiments were established in central New York State in spring, 1987, to evaluate the potential of Salix for wood biomass production using ultrashort-rotation intensive-culture techniques. Five selected willow clones and one hybrid poplar clone planted at 1 x 1 foot spacing were tested for biomass production with annual coppicing. This report presents results of this research as of December 31, 1990. (VC)

  1. Available data support protection of the Southwestern Willow Flycatcher under the Endangered Species Act

    Science.gov (United States)

    Theimer, Tad C.; Smith, Aaron D.; Mahoney, Sean M.; Ironside, Kirsten E.

    2016-01-01

    Zink (2015) argued there was no evidence for genetic, morphological, or ecological differentiation between the federally endangered Southwestern Willow Flycatcher (Empidonax traillii extimus) and other Willow Flycatcher subspecies. Using the same data, we show there is a step-cline in both the frequency of a mtDNA haplotype and in plumage variation roughly concordant with the currently recognized boundary between E. t. extimus and E. t adastus, the subspecies with which it shares the longest common boundary. The geographical pattern of plumage variation is also concordant with previous song analyses differentiating those 2 subspecies and identified birds in one low-latitude, high-elevation site in Arizona as the northern subspecies. We also demonstrate that the ecological niche modeling approach used by Zink yields the same result whether applied to the 2 flycatcher subspecies or to 2 unrelated species, E. t. extimus and Yellow Warbler (Setophaga petechia). As a result, any interpretation of those results as evidence for lack of ecological niche differentiation among Willow Flycatcher subspecies would also indicate no differentiation among recognized species and would therefore be an inappropriate standard for delineating subspecies. We agree that many analytical techniques now available to examine genetic, morphological, and ecological differentiation would improve our understanding of the distinctness (or lack thereof) of Willow Flycatcher subspecies, but we argue that currently available evidence supports protection of the Southwestern Willow Flycatcher under the Endangered Species Act.

  2. Can energy willow (Salix sp.) remediate cadmium- and nickel-contaminated fish farm sludge?

    DEFF Research Database (Denmark)

    Pedersen, Marianne Bruus

    it meets the criteria. Phytoremediation by willow may combine accumulation of cadmium and nickel from the sludge with the production of an energy crop. The ability of eight selected willow clones to take up and tolerate cadmium and nickel was studied in pots under outdoor conditions. Fish farm sludge...

  3. Phytoextraction of risk elements by willow and poplar trees.

    Science.gov (United States)

    Kacálková, Lada; Tlustoš, Pavel; Száková, Jiřina

    2015-01-01

    To characterize the phytoextraction efficiency of two clones of willow trees (Salix x smithiana Willd., Salix rubens) and two clones of poplar trees (Populus nigra x maximowiczii, Populus nigra Wolterson) were planted in contaminated soil (0.4-2.0 mg Cd.kg(-1), 78-313 mg Zn.kg(-1), 21.3-118 mg Cu.kg(-1)). Field experiment was carried out in Czech Republic. The study investigated their ability to accumulate heavy metals (Cd, Zn, and Cu) in harvestable plant parts. The poplars produced higher amount of biomass than willows. Both Salix clones accumulated higher amount of Cd, Zn and Cu in their biomass (maximum 6.8 mg Cd.kg(-1), 909 mg Zn.kg(-1), and 17.7 mg Cu.kg(-1)) compared to Populus clones (maximum 2.06 mg Cd.kg(-1), 463 mg Zn.kg(-1), and 11.8 mg Cu.kg(-1)). There were no significant differences between clones of individual species. BCs for Cd and Zn were greater than 1 (the highest in willow leaves). BCs values of Cu were very low. These results indicate that Salix is more suitable plant for phytoextraction of Cd and Zn than Populus. The Cu phytoextraction potential of Salix and Populus trees was not confirmed in this experiment due to low soil availability of this element.

  4. Test of aerobic TCE degradation by willows (Salix viminalis) and willows inoculated with TCE-cometabolizing strains of Burkholderia cepacia

    DEFF Research Database (Denmark)

    Clausen, Lauge Peter Westergaard; Broholm, Mette Martina; Gosewinkel, Ulrich Bay

    2017-01-01

    . cepacia (301C, PR1-31 and VM1330-pTOM), using chloride formation as an indicator of dehalogenation. Willows were grown in non-sterile, hydroponic conditions for 3 weeks in chloride-free nutrient solution spiked with TCE. TCE was added weekly due to rapid loss by volatilization. Chloride and TCE...

  5. Comparing predicted yield and yield stability of willow and Miscanthus across Denmark

    DEFF Research Database (Denmark)

    Larsen, Søren; Jaiswal, Deepak; Bentsen, Niclas Scott

    2016-01-01

    was 12.1 Mg DM ha−1 yr−1 for willow and 10.2 Mg DM ha−1 yr−1 for Miscanthus. Coefficent of variation as a measure for yield stability was poorest on the sandy soils of northern and western Jutland and the year-to-year variation in yield was greatest on these soils. Willow was predicted to outyield...... Miscanthus on poor, sandy soils whereas Miscanthus was higher yielding on clay-rich soils. The major driver of yield in both crops was variation in soil moisture, with radiation and precipitation exerting less influence. This is the first time these two major feedstocks for northern Europe have been compared....... The semi-mechanistic crop model BioCro was used to simulate the production of both short rotation coppice (SRC) willow and Miscanthus across Denmark. Predictions were made from high spatial resolution soil data and weather records across this area for 1990-2010. The potential average, rain-fed mean yield...

  6. Greenhouse gas emissions from willow-based electricity: a scenario analysis for Portugal and The Netherlands

    NARCIS (Netherlands)

    Rebelo de Mira, R.; Kroeze, C.

    2006-01-01

    This study focuses on greenhouse gas emissions from power plants using willow as fuel compared to those using fossil fuels. More specifically, we quantify emissions of nitrous oxide (N2O) from soils on which willow is grown, and compare these to emissions of carbon dioxide (CO2) from fossil

  7. Wind in the Willows--Theatre Activity Packet.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.

    Part of the New York City Board of Education's Early Stages program, and intended for elementary and secondary school teachers who wish to include a unit on theater in their classes, this guide offers suggestions for lessons and activities to accompany viewing a performance of "Wind in the Willows" at the Nederlander Theater. Part one of…

  8. GIS-BASED location optimization of a biomass conversion plant on contaminated willow in the Campine region (Belgium)

    International Nuclear Information System (INIS)

    Voets, Thomas; Neven, An; Thewys, Theo; Kuppens, Tom

    2013-01-01

    The Campine region is diffusely contaminated with heavy metals like cadmium. Since traditional excavation techniques are too expensive, phytoremediation is preferred as a remediation technique. In a previous study, the biomass potential from phytoremediation of contaminated agricultural land in the Campine region in Belgium was assessed. Based on recently upgraded figures of willow potential from phytoremediation on agricultural land in the seven most contaminated municipalities of the Belgian Campine region, the current paper uses GIS-knowledge to investigate which of three previously identified locations is most suitable for a biomass plant, taking into account the spatial distribution of the contaminated willow supply and the total cost of willow transport. Biomass transport distance from the centroid of each contaminated agricultural parcel to each of the three potential biomass plant locations was determined following Euclidian distance calculations and distance calculations over the existing road network. A transport cost model consisting of distance fixed and distance dependent biomass transport costs was developed. Of the locations identified, the Overpelt Fabriek site results in the lowest biomass transport distance and costs. When willow allocation for each parcel occurs based on the nearest potential plant location, transport costs are on average 23% lower than when all biomass is transported to the single Overpelt Fabriek site location. Therefore, when only considering transport costs, installing a smaller plant at each of the three potential plant locations would be less expensive than when installing a single biomass plant at the Overpelt Fabriek site. -- Highlights: ► Overpelt Fabriek site most attractive for time frames considered. ► Average tortuosity factor in Campine region between 1.27 and 1.42. ► Share of willow transport costs in willow supply costs 21%. ► Optimal allocation of willow results in lower transport costs

  9. Yield and Water Quality Impacts of Field-Scale Integration of Willow into a Continuous Corn Rotation System.

    Science.gov (United States)

    Zumpf, Colleen; Ssegane, Herbert; Negri, Maria Cristina; Campbell, Patty; Cacho, Julian

    2017-07-01

    Agricultural landscape design has gained recognition by the international environmental and development community as a strategy to address multiple goals in land, water, and ecosystem service management; however, field research is needed to quantify impacts on specific local environments. The production of bioenergy crops in specific landscape positions within a grain-crop field can serve the dual purpose of producing cellulosic biomass (nutrient recovery) while also providing regulating ecosystem services to improve water quality (nutrient reduction). The effectiveness of such a landscape design was evaluated by the strategic placement of a 0.8-ha short-rotation shrub willow ( Seemen) bioenergy buffer along marginal soils in a 6.5-ha corn ( L.) field in a 6-yr field study in central Illinois. The impact of willow integration on water quality (soil water, shallow groundwater leaching, and crop nutrient uptake) and quantity (soil moisture and transpiration) was monitored in comparison with corn in the willow's first cycle of growth. Willows significantly reduced nitrate leachate in shallow subsurface water by 88% while maintaining adequate nutrient and water usage. Results suggest that willows offer an efficient nutrient-reduction strategy and may provide additional ecosystem services and benefits, including enhanced soil health. However, low values for calculated willow biomass will need to be readdressed in the future as harvest data become available to understand contributing factors that affected productivity beyond nutrient availability. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. Use of willows in evapotranspirative systems for onsite wastewater management – theory and experiences from Denmark

    DEFF Research Database (Denmark)

    Brix, Hans; Arias, Carlos Alberto

    2011-01-01

    aspects of ET systems is their ability to evapotranspire all of the sewage discharged into the systems and the rain falling onto the systems. On an annual basis the ET should equal the amount of wastewater discharged into the system plus the amount of precipitation falling onto the system. Part...... with clones of willow (Salix viminalis L.). The surface area of the systems depends on the amount and quality of the sewage to be treated and the local annual rainfall. A single household in Denmark typically requires between 120 and 300 m2. The annual precipitation at the site of construction is an important...... dimensioning parameter. Settled sewage is dispersed underground into the bed under pressure. The stems of the willows are harvested on a regular basis to stimulate the growth of the willows and to remove some nutrients and heavy metals. In this paper, the theory behind the operation of willow based ET systems...

  11. White willow sexual regeneration capacity under estuarine conditions in times of climate change

    Science.gov (United States)

    Markus-Michalczyk, Heike; Hanelt, Dieter; Denstorf, Julian; Jensen, Kai

    2016-10-01

    Tidal wetlands provide both habitats for coastal populations and wildlife, and ecosystem services for human welfare. Building with nature regarding cost-effective coastal protection is of increasing interest. Much research has been carried out on plant reproduction capacities in mangroves and salt marshes, but less is known on this issue in tidal freshwater wetlands. Willows are being successfully used for bank stabilization in riverine habitats, however, today white willow softwood forests in tidal wetlands are highly fragmented, and restoration is required e.g. by the European Habitats Directive. Recently, tolerance to increasing salinity and tidal flooding was found for vegetative propagules of floodplain willows. However, the establishment of autochthonous sexual recruits is necessary to conserve the genetic diversity of local populations, and thus may be preferable in restoration. The germination and early seedling establishment of Salix alba (white willow) was experimentally studied under simulated estuarine conditions. The species tolerance to increasing salinity (0, 0.5, 1, 1.5, and 2) was tested in a climate chamber, and its tolerance to flooding at different tidal treatments (control, spring tide, daily tide 15 min and 2 h flooding) in the greenhouse. Germination was neither affected by increasing salinity nor by tidal flooding. Salix seedlings established up to salinity 1.5, but cotyledon performance and radicle growth was largely reduced at salinity 2. Under tidal flooding, seedling growth was similar in all treatments. However, in the treatments with daily tides seedling anchorage in the substrate took more than two weeks, and fewer seedlings reached a suitable length to approach the high water line. We assess S. alba sexual regeneration under estuarine conditions as generally possible. Further studies are needed on the effects of sedimentation-erosion processes on willow establishment in the field, especially on feedbacks between Salix survival and

  12. Arthropods of native and exotic vegetation and their association with willow flycatchers and Wilson's warblers

    Science.gov (United States)

    Linda S. DeLay; Deborah M. Finch; Sandra Brantley; Richard Fagerlund; Michael D. Means; Jeffrey F. Kelly

    1999-01-01

    We compared abundance of migrating Willow Flycatchers and Wilson's Warblers to the abundance of arthropods in exotic and native vegetation at Bosque del Apache National Wildlife Refuge. We trapped arthropods using glue-boards in 1996 and 1997 in the same cottonwood, saltcedar, and willow habitats where we mist-netted birds during spring and fall migration. There...

  13. 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

  14. Physiological and morphological responses of pine and willow saplings to post-fire salvage logging

    Science.gov (United States)

    Millions, E. L.; Letts, M. G.; Harvey, T.; Rood, S. B.

    2015-12-01

    With global warming, forest fires may be increasing in frequency, and post-fire salvage logging may become more common. The ecophysiological impacts of this practice on tree saplings remain poorly understood. In this study, we examined the physiological and morphological impacts of increased light intensity, due to post-fire salvage logging, on the conifer Pinus contorta (pine) and deciduous broadleaf Salix lucida (willow) tree and shrub species in the Crowsnest Pass region of southern Alberta. Photosynthetic gas-exchange and plant morphological measurements were taken throughout the summer of 2013 on approximately ten year-old saplings of both species. Neither species exhibited photoinhibition, but different strategies were observed to acclimate to increased light availability. Willow saplings were able to slightly elevate their light-saturated rate of net photosynthesis (Amax) when exposed to higher photosynthetic photon flux density (PPFD), thus increasing their growth rate. Willow also exhibited increased leaf inclination angles and leaf mass per unit area (LMA), to decrease light interception in the salvage-logged plot. By contrast, pine, which exhibited lower Amax and transpiration (E), but higher water-use efficiency (WUE = Amax/E) than willow, increased the rate at which electrons were moved through and away from the photosynthetic apparatus in order to avoid photoinhibition. Acclimation indices were higher in willow saplings, consistent with the hypothesis that species with short-lived foliage exhibit greater acclimation. LMA was higher in pine saplings growing in the logged plot, but whole-plant and branch-level morphological acclimation was limited and more consistent with a response to decreased competition in the logged plot, which had much lower stand density.

  15. Environmental performance of gasified willow from different lands including land-use changes

    DEFF Research Database (Denmark)

    Saez de Bikuna Salinas, Koldo; Hauschild, Michael Zwicky; Pilegaard, Kim

    2017-01-01

    A life-cycle assessment (LCA) of a low-input, short rotation coppice (SRC) willow grown on different Danish lands was performed. Woodchips are gasified, producer gas is used for co-generation of heat and power (CHP) and the ash-char output is applied as soil amendment in the field. A hybrid model...... for abandoned farmland, as a relative C stock loss compared to natural regeneration. ILUC results show that area related GHG emissions are dominant (93% of iLUCfood and 80% of iLUCfeed), transformation being more important (82% of iLUCfood) than occupation (11%) impacts. LCA results show that CHP from willow...

  16. Dam Break Analysis of Embankment Dams Considering Breach Characteristics

    Directory of Open Access Journals (Sweden)

    Abolfazl Shamsaei

    2004-05-01

    Full Text Available The study of dam's break, needs the definition of various parameters such as the break cause, its type, its dimension and the duration of breach development. The precise forecast for different aspects of the breach is one of the most important factors for analyzing it in embankment dam. The characteristics of the breach and determination of their vulnerability has the most effect on the waves resulting from dam break. Investigating, about the parameters of the breach in "Silveh" earth dam have been determined using the suitable model. In Silve dam a trapezoid breach with side slope z=0.01m and the average base line b=80m was computed. The duration of the breaches development is 1.9 hour. Regarding the above results and the application of DAM Break software the consequences of the probable break of the dam was determined. The analysis of the results of water covering of the city of Piranshahr located 12km from silve dam confirms that in 3 hours the water will reach the height (level of 1425 meters.

  17. Conservation assessment for the autumn willow in the Black Hills National Forest, South Dakota and Wyoming

    Science.gov (United States)

    J. Hope Hornbeck; Carolyn Hull Sieg; Deanna J. Reyher

    2003-01-01

    Autumn willow, Salix serissima (Bailey) Fern., is an obligate wetland shrub that occurs in fens and bogs in the northeastern United States and eastern Canada. Disjunct populations of autumn willow occur in the Black Hills of South Dakota. Only two populations occur on Black Hills National Forest lands: a large population at McIntosh Fen and a small...

  18. Ecophysiology of riparian cottonwood and willow before, during, and after two years of soil water removal.

    Science.gov (United States)

    Hultine, K R; Bush, S E; Ehleringer, J R

    2010-03-01

    Riparian cottonwood/willow forest assemblages are highly valued in the southwestern United States for their wildlife habitat, biodiversity, and watershed protection. Yet these forests are under considerable threat from climate change impacts on water resources and land-use activities to support human enterprise. Stream diversions, groundwater pumping, and extended drought have resulted in the decline of cottonwood/willow forests along many riparian corridors in the Southwest and, in many cases, the replacement of these forests with less desirable invasive shrubs and trees. Nevertheless, ecophysiological responses of cottonwood and willow, along with associated ecohydrological feedbacks of soil water depletion, are not well understood. Ecophysiological processes of mature Fremont cottonwood and coyote willow stands were examined over four consecutive growing seasons (2004-2007) near Salt Lake City, Utah, USA. The tree stands occurred near the inlet of a reservoir that was drained in the spring of 2005 and remained empty until mid-summer of 2006, effectively removing the primary water source for most of two growing seasons. Stem sap flux density (Js) in cottonwood was highly correlated with volumetric soil moisture (theta) in the upper 60 cm and decreased sevenfold as soil moisture dropped from 12% to 7% after the reservoir was drained. Conversely, Js in willow was marginally correlated with 0 and decreased by only 25% during the same period. Opposite patterns emerged during the following growing season: willow had a lower whole-plant conductance (kt) in June and higher leaf carbon isotope ratios (delta13C) than cottonwood in August, whereas k(t) and delta13C were otherwise similar between species. Water relations in both species recovered quickly from soil water depletion, with the exception that sapwood area to stem area (As:Ast) was significantly lower in both species after the 2007 growing season compared to 2004. Results suggest that cottonwood has a greater

  19. UTILIZATION OF ANIMAL MEAL FOR GROWING OF WILLOW DEDICATED FOR ENERGY

    Directory of Open Access Journals (Sweden)

    Anna Nogalska

    2016-09-01

    Full Text Available The aim of the study was to evaluate the effects of increased rates of meat and bone meal (MBM to the soil on biomass yield, nitrogen (N and phosphorus (P content, and their accumulation in above ground biomass Salix viminalis, as well as the content of mineral N and available P forms in the soil. A two-year pot experiment was conducted at Warmia and Mazury University in Olsztyn (north-eastern Poland. Average biomass yield from two seasons of the studies was three higher from MBM treatments comparing to unfertilized control. Higher rates of MBM particularly in the second year showed higher yielding potential compared with mineral fertilizers. Willow biomass harvested from MBM treatments generally showed lower content of studied nutrients than willow from control treatment. It was found that in relation to the control accumulation of N in willow above ground biomass was significantly lower for 0.5% MBM treatment and significantly higher for the treatment with the highest rate (2.0%. The higher accumulation of P was found in the second year after MBM application, except treatment with the lowest MBM rate. Correlation coefficients values indicated that there is a relation between MBM rate and content of mineral N and available P in soil.

  20. Assessment of check-dam groundwater recharge with water-balance calculations

    Science.gov (United States)

    Djuma, Hakan; Bruggeman, Adriana; Camera, Corrado; Eliades, Marinos

    2017-04-01

    Studies on the enhancement of groundwater recharge by check-dams in arid and semi-arid environments mainly focus on deriving water infiltration rates from the check-dam ponding areas. This is usually achieved by applying simple water balance models, more advanced models (e.g., two dimensional groundwater models) and field tests (e.g., infiltrometer test or soil pit tests). Recharge behind the check-dam can be affected by the built-up of sediment as a result of erosion in the upstream watershed area. This natural process can increase the uncertainty in the estimates of the recharged water volume, especially for water balance calculations. Few water balance field studies of individual check-dams have been presented in the literature and none of them presented associated uncertainties of their estimates. The objectives of this study are i) to assess the effect of a check-dam on groundwater recharge from an ephemeral river; and ii) to assess annual sedimentation at the check-dam during a 4-year period. The study was conducted on a check-dam in the semi-arid island of Cyprus. Field campaigns were carried out to measure water flow, water depth and check-dam topography in order to establish check-dam water height, volume, evaporation, outflow and recharge relations. Topographic surveys were repeated at the end of consecutive hydrological years to estimate the sediment built up in the reservoir area of the check dam. Also, sediment samples were collected from the check-dam reservoir area for bulk-density analyses. To quantify the groundwater recharge, a water balance model was applied at two locations: at the check-dam and corresponding reservoir area, and at a 4-km stretch of the river bed without check-dam. Results showed that a check-dam with a storage capacity of 25,000 m3 was able to recharge to the aquifer, in four years, a total of 12 million m3 out of the 42 million m3 of measured (or modelled) streamflow. Recharge from the analyzed 4-km long river section without

  1. Some environmental impacts of short rotation willow coppice

    International Nuclear Information System (INIS)

    Slater, F.M.; Hodson, R.W.; Randrson, P.F.; Lynn, S.F.

    1997-01-01

    Short rotation willow coppice is a relatively new crop in upland Britain, and particularly in Environmentally Sensitive Areas the conservation and environmental effect of biomass crops needs to be evaluated. Investigations of sewage-sludge-treated plots in mid-Wales show that, because weed control was inadequate, recovery of the flora to its semi-natural precultivated state was rapid within and between experimental plots. Soil invertebrates responded to temporal stimuli before all else. Foliar-feeding invertebrates were greater in plots which had added fertilizer. Following cultivation voles were generally lost from the ploughed areas but field mice remained. Birds were studied in more extensive areas of short rotation coppice in central England and the assemblage of species was found to be similar to those found in conventional coppice but with a foreshortened successional sequence. The conservation value of short rotation willow coppice lies mainly in the abundant foliar invertebrates that provide a rich source of food for small passerine birds, particularly summer migrants. It also provides good cover for game birds - and their predators. (author)

  2. NRC inventory of dams

    International Nuclear Information System (INIS)

    Lear, G.E.; Thompson, O.O.

    1983-01-01

    The NRC Inventory of Dams has been prepared as required by the charter of the NRC Dam Safety Officer. The inventory lists 51 dams associated with nuclear power plant sites and 14 uranium mill tailings dams (licensed by NRC) in the US as of February 1, 1982. Of the 85 listed nuclear power plants (148 units), 26 plants obtain cooling water from impoundments formed by dams. The 51 dams associated with the plants are: located on a plant site (29 dams at 15 plant sites); located off site but provide plant cooling water (18 dams at 11 additional plant sites); and located upstream from a plant (4 dams) - they have been identified as dams whose failure, and ensuing plant flooding, could result in a radiological risk to the public health and safety. The dams that might be considered NRC's responsibility in terms of the federal dam safety program are identified. This group of dams (20 on nuclear power plant sites and 14 uranium mill tailings dams) was obtained by eliminating dams that do not pose a flooding hazard (e.g., submerged dams) and dams that are regulated by another federal agency. The report includes the principal design features of all dams and related useful information

  3. Willow yield is highly dependent on clone and site

    DEFF Research Database (Denmark)

    Ugilt Larsen, Søren; Jørgensen, Uffe; Lærke, Poul Erik

    2014-01-01

    Use of high-yielding genotypes is one of the means to achieve high yield and profitability in willow (Salix spp.) short rotation coppice. This study investigated the performance of eight willow clones (Inger, Klara, Linnea, Resolution, Stina, Terra Nova, Tora, Tordis) on five Danish sites......, differing considerably in soil type, climatic conditions and management. Compared to the best clone, the yield was up to 36 % lower for other clones across sites and up to 51 % lower within sites. Tordis was superior to other clones with dry matter yields between 5.2 and 10.2 Mg ha−1 year−1 during the first...... 3-year harvest rotation, and it consistently ranked as the highest yielding clone on four of the five sites and not significantly lower than the highest yielding clone on the fifth site. The ranking of the other clones was more dependent on site with significant interaction between clone and site...

  4. Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees.

    Science.gov (United States)

    Algreen, Mette; Trapp, Stefan; Rein, Arno

    2014-01-01

    The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from three reference sites. Wood from both tree species had similar background concentrations at 0.5 mg kg(-1) for cadmium (Cd), 1.6 mg kg(-1) for copper (Cu), 0.3 mg kg(-1) for nickel (Ni), and 25 mg kg(-1) for zinc (Zn). Concentrations of chromium (Cr) and lead (Pb) were below or close to detection limit. Concentrations in wood from the highly polluted site were significantly elevated, compared to references, in particular for willow. The conclusion from these results is that tree coring could be used successfully to identify strongly heavy metal-polluted soil for Cd, Cu, Ni, Zn, and that willow trees were superior to poplars, except when screening for Ni. Phytoextraction of HMs was quantified from measured concentration in wood at the most polluted site. Extraction efficiencies were best for willows and Cd, but below 0.5% over 10 years, and below 1‰ in 10 years for all other HMs.

  5. Radiocaesium uptake and cycling in willow short rotation coppice

    International Nuclear Information System (INIS)

    Gommers, A.

    2002-01-01

    The document is an abstract of a PhD thesis. The study investigates the uptake and cycling of radiocaesium in willow short rotation coppice. Different factors influencing the soil-to-wood transfer of radiocaesium were investigated, among others the type of minerals, supply of potassium and soil composition

  6. Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy

    International Nuclear Information System (INIS)

    Zimmer, Dana; Kruse, Jens; Baum, Christel; Borca, Camelia; Laue, Michael; Hause, Gerd; Meissner, Ralph; Leinweber, Peter

    2011-01-01

    Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between As and Fe was explained by the different sorption/desorption properties of As(III) and As(V). The Cu and Zn intensities were not associated with the intensity of Fe in the plaque, which seems to be a willow-specific difference compared to other wetland plants. These results suggested that willows are especially suited to stabilize low-phytoextractable elements like Cu and As in their roots and rhizosphere. Thus, short rotation coppicing of willows may be a practical approach to mitigate the adverse effects of floodplain soil contamination. - Research highlights: → Elemental distributions were mapped on willow roots for the first time by synchrotron-based X-ray fluorescence. → Ca, Cu, Ni, S and Zn were enriched in the aerenchyma but As, Fe and Mn formed root plaques. → The Cu and Zn enrichments in aerenchyma but absence in plaques appeared to be willow-specific. → In the plaques were three groups of pixels which strongly differed in the As to Fe and As to Mn ratios. → This indicated different species of these redox-sensitive elements.

  7. Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, Dana, E-mail: dana.zimmer@uni-rostock.de [Soil Science, University of Rostock, Justus-von-Liebig-Weg 6, D-18051 Rostock (Germany); Kruse, Jens; Baum, Christel [Soil Science, University of Rostock, Justus-von-Liebig-Weg 6, D-18051 Rostock (Germany); Borca, Camelia [Paul Scherrer Institute, Swiss Light Source, CH-5232 Villigen PSI (Switzerland); Laue, Michael [Electron Microscopy Centre, University of Rostock, Medical Faculty, Strempelstr. 14, D-18057 Rostock (Germany); Hause, Gerd [Microscopy Unit, Biocenter of the University of Halle, Weinbergweg 22, D-06120 Halle/Saale (Germany); Meissner, Ralph [UFZ-Helmholtz Centre for Environmental Research, Department of Soil Physics, Lysimeter Station, Dorfstrasse 55, D-39615 Falkenberg (Germany); Leinweber, Peter [Soil Science, University of Rostock, Justus-von-Liebig-Weg 6, D-18051 Rostock (Germany)

    2011-09-01

    Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between As and Fe was explained by the different sorption/desorption properties of As(III) and As(V). The Cu and Zn intensities were not associated with the intensity of Fe in the plaque, which seems to be a willow-specific difference compared to other wetland plants. These results suggested that willows are especially suited to stabilize low-phytoextractable elements like Cu and As in their roots and rhizosphere. Thus, short rotation coppicing of willows may be a practical approach to mitigate the adverse effects of floodplain soil contamination. - Research highlights: {yields} Elemental distributions were mapped on willow roots for the first time by synchrotron-based X-ray fluorescence. {yields} Ca, Cu, Ni, S and Zn were enriched in the aerenchyma but As, Fe and Mn formed root plaques. {yields} The Cu and Zn enrichments in aerenchyma but absence in plaques appeared to be willow-specific. {yields} In the plaques were three groups of pixels which strongly differed in the As to Fe and As to Mn ratios. {yields} This indicated different species of these redox-sensitive elements.

  8. Differential impacts of willow and mineral fertilizer on bacterial communities and biodegradation in diesel fuel oil-contaminated soil

    Directory of Open Access Journals (Sweden)

    Mary-Cathrine C.E. Leewis

    2016-06-01

    Full Text Available Despite decades of research there is limited understanding of how vegetation impacts the ability of microbial communities to process organic contaminants in soil. Using a combination of traditional and molecular assays, we examined how phytoremediation with willow and/or fertilization affected the microbial community present and active in the transformation of diesel contaminants. In a pot study, willow had a significant role in structuring the total bacterial community and resulted in significant decreases in diesel range organics (DRO. However, stable isotope probing (SIP indicated that fertilizer drove the differences seen in community structure and function. Finally, analysis of the total variance in both pot and SIP experiments indicated an interactive effect between willow and fertilizer on the bacterial communities. This study clearly demonstrates that a willow native to Alaska accelerates DRO degradation, and together with fertilizer, increased aromatic degradation by shifting microbial community structure and the identity of active naphthalene degraders.

  9. Dams

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset �is generated from from the Vermont Dam Inventory (VDI). The VDI is managed by the VT DEC's Dam Safety and Hydrology Section and contains information...

  10. Woody plant willow in function of river water protection

    Directory of Open Access Journals (Sweden)

    Babincev Ljiljana M.

    2011-01-01

    Full Text Available Coastal area surrounding the river Ibar, in the area between cities of Kosovska Mitrovica and Leposavić in the north of Kosovo and Metohija, is occupied with seven industrial waste dumps. These dumps were all part of the exploitation and flotation refinement of raw mineral materials, metallurgic refinement of concentrates, chemical industry, industrial refinement and energetic facilities of Trepča industrial complex. The existing waste dumps, both active and inactive, are of heterogenic chemical composition. Its impact on the river water is shown by the content of heavy metals found in it. Removal of lead, cadmium and zinc would be economically unrewarding, regardless of the technology used. Wooden plant that prevails in this area is white willow. This work is focused on the removal of heavy metals (Pb, Cd and Zn from the water of the river Ibar using white willow. Roots of the willow are cultivated using the method of water cultures in an individual solution of heavy metals and river water sample. The preparation of the samples for analysis was performed by burning the herbal material and dissolving ashes in the appropriate acids. The concentrations of metals were determined by the stripping analysis. In the investigated heavy metal solutions the biomass increase is 25.6% in lead solution, 27.3% in cadmium and 30.7% in zinc solution. The increase of biomass in nutritional solution, without the heavy metals, is 32.4% and in river water sample 27.5%. The coefficient of bioaccumulation in solutions with heavy metals is 1.6% in lead solution, 1.9% in cadmium and 2.2% in zinc solution. Heavy metals accumulation is 18.74 μg of lead, 20.09 μg of cadmium and 22.89 μg of zinc. The coefficient of bioaccumulation of the water samples, that contained 44.83 μg/dm3 of lead, 29.21 μg/dm3 of cadmium and 434.00 μg/dm3 of zinc, during the period of 45 days, was 30.3% for lead, 53.4% for cadmium and 3.9% for zinc. The concentrations of accumulated metals

  11. SELECTIVE FORAGING ON WOODY SPECIES BY THE BEAVER CASTOR FIBER, AND ITS IMPACT ON A RIPARIAN WILLOW FOREST

    NARCIS (Netherlands)

    NOLET, BA; HOEKSTRA, A; OTTENHEIM, MM

    1994-01-01

    Beavers were re-introduced in the Biesbosch, The Netherlands, a wood dominated by willows Salix spp. Conservationists expected that herbivory by beavers would enhance succession to a mixed broad-leaved forest. Willows formed the staple food of the beavers, but they removed only 1.4% of the standing

  12. Above- and Belowground Development of a Fast-Growing Willow Planted in Acid-Generating Mine Technosol.

    Science.gov (United States)

    Guittonny-Larchevêque, M; Lortie, S

    2017-11-01

    Surface metal mining produces large volumes of waste rocks. If they contain sulfide minerals, these rocks can generate a flow of acidic water from the mining site, known as acid mine drainage (AMD), which increases trace metals availability for plant roots. Adequate root development is crucial to decreasing planting stress and improving phytoremediation with woody species. However, techniques to improve revegetation success rarely take into account root development. An experiment was conducted at a gold mine in Quebec, Canada, to evaluate the establishment ability over 3 yr of a fast-growing willow ( Sx64) planted in acid-generating waste rocks. The main objective was to study root development in the soil profile and trace element accumulation in leaves among substrates varying in thickness (0, 20, and 40 cm of soil) and composition (organic carbon [OC] and alkaline AMD treatment sludge). Trees directly planted in waste rocks survived well (69%) but had the lowest productivity (lowest growth in height and diameter, aerial biomass, total leaf area, and root-system size). By contrast, the treatment richer in OC showed the greatest aerial biomass and total leaf area the first year; the thicker treatment resulted in the greatest growth in height and diameter, aboveground biomass, and root-system size in both the first and third years. Willow root development was restricted to soil layers during the first year, but this restriction was overcome in the third year after planting. Willow accumulation factors in leaves were below one for all investigated trace metals except for zinc (Zn), cadmium (Cd), and strontium. For Cd and Zn, concentrations increased with time in willow foliage, decreasing the potential of this willow species use for phytostabilization, despite its ability to rapidly develop extensive root systems in the mine Technosol. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  13. Japan`s largest composition dam, aiming for harmony with nature. Chubetsu dam; Shizen tono chowa wo mezasu, Nippon ichi no fukugo dam. Chubetsu dam

    Energy Technology Data Exchange (ETDEWEB)

    Mizushima, T. [Hokkaido Development Bureau, Hokkaido Development Agency, Sapporo (Japan)

    1994-08-15

    This paper introduces Chubetsu Dam planned with a large-scale embankment having a river bed width of 600 m. Chubetsu Dam is being constructed with such objectives as flood control of Ishikari River, river flow rate maintenance, drinking water supply, irrigation water supply and power generation. The dam site is a gravel bed having a river bed width of 600 m and a maximum foundation rock thickness of 40 m, requiring evaluations as a dam foundation and discussions of water shielding methods. As a result of discussions at the Chubetsu Dam technical discussion committee, the dam type is decided to be a composition dam consisting of a gravity type concrete dam on the left river side and a central core type fill dam using a part of the gravel bed as the foundation on the right river side. A continuous underground wall system is planned to be used for shielding water in the gravel foundation. In discussing the anti-seismic properties, analyses for bank construction and water filling to derive stress and deformation conditions prior to an earthquake and a time-history response analysis to derive conditional changes during the earthquake are performed. According to the results thereof, evaluations are given on the safety by compounding the stress and the acceleration. In plans to improve the surrounding areas, an area will be provided upstream the reservoir where the water level is kept constant to serve as a bird sanctuary. 7 figs.

  14. Phytoextraction of heavy metals by willows growing in biosolids under field conditions.

    Science.gov (United States)

    Laidlaw, W S; Arndt, S K; Huynh, T T; Gregory, D; Baker, A J M

    2012-01-01

    Biosolids produced by sewage treatment facilities can exceed guideline thresholds for contaminant elements. Phytoextraction is one technique with the potential to reduce these elements allowing reuse of the biosolids as a soil amendment. In this field trial, cuttings of seven species/cultivars of Salix(willows) were planted directly into soil and into biosolids to identify their suitability for decontaminating biosolids. Trees were irrigated and harvested each year for three consecutive years. Harvested biomass was weighed and analyzed for the contaminant elements: As, Cd, Cu, Cr, Hg, Pb, Ni, and Zn. All Salix cultivars, except S. chilensis, growing in soils produced 10 to 20 t ha(-1) of biomass, whereas most Salix cultivars growing in biosolids produced significantly less biomass (metals from biosolids, driven by superior biomass increases and not high tissue concentrations. The willows were effectual in extracting the most soluble/exchangeable metals (Cd, 0.18; Ni, 0.40; and Zn, 11.66 kg ha(-1)), whereas Cr and Cu were extracted to a lesser degree (0.02 and 0.11 kg ha(-1)). Low bioavailable elements, As, Hg, and Pb, were not detectable in any of the aboveground biomass of the willows. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  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. Damming evidence : Canada and the World Commission on Dams

    Energy Technology Data Exchange (ETDEWEB)

    Vert, P.; Parkinson, B.

    2003-06-01

    Large hydroelectric projects have been met with strong resistance from affected communities, particularly indigenous groups who have been displaced from their flooded communities following the damming of a river. The World Commission on Dams (WCD) was formed in 1998 to review the effectiveness of large dams and develop internationally acceptable guidelines and standards for large dams or hydro energy projects. The Canadian government, through the Canadian International Development Agency, was one of many governments to fund the WCD. However, the authors argue that despite the financial support, the Canadian government was absent from any effort to follow-up on the recommendations of the WCD. The seven strategic priorities in the decision making process include: (1) gaining public acceptance, (2) comprehensive option assessment of water, energy, food and development needs, (3) addressing existing dams to improve the benefits that can be derived from them, (4) sustaining livelihoods, (5) recognizing the entitlements and sharing benefits, (6) ensuring compliance, and (7) sharing rivers for peace, development and security. This report offers a means to assess planned or existing dams and presents a set of guidelines for good practices linked to the seven strategic priorities. Ten case studies from around the world were presented, including the Three Gorges Dam in China. 154 refs., 3 figs., 3 appendices.

  17. Proceedings of the Canadian Dam Association's 2006 annual conference: dams: past, present and future

    International Nuclear Information System (INIS)

    2006-01-01

    This conference addressed particular technical challenges regarding the operation of dams with particular focus on best practices for improving dam management and safety. It featured 4 workshops and a technical program led by experts on dams and tailings facilities that addressed topics such as dam construction, design and rehabilitation; dam management in a hydrological uncertainty context; monitoring, instrumentation and maintenance; dam behaviour; dam safety, dam failure and practical approaches to emergency preparedness planning for dam owners; historical aspects and environmental issues and conflicting water use. Recent developments in dam construction were reviewed along with discharge and debris management, tailings dam issues, asset management, seismic issues, public safety, seepage monitoring, flow control, dam rehabilitation, concrete testing, hydrotechnical issues, risk assessment methodology, and dam safety guidelines for extreme flood analyses and their applications. All 80 presentations from this conference have been catalogued separately for inclusion in this database. refs., tabs., figs

  18. Proceedings of the 2010 Canadian Dam Association's public safety around dams workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Nearly 30 people have drowned in dam-related incidents over the last 10 years in Canada. The Canadian public is now calling for improved safety guidelines. Public interaction with dams is increasing as a result of interest in extreme sports and perceived rights of access. However, many members of the public are not aware of the dangers posed by dams. This workshop provided a forum to discuss proposals for a draft publication of the Canadian Dam Association (CDA) guidelines for public safety and security around dams. Issues related to current legislation and liability were discussed. Methods of increasing public awareness of the hazards posed by dams included increased signage in dam locations, the use of audible and visual alert systems, and the use of booms and buoys. The responsibilities of dam owners in ensuring the safety of dams were also discussed. The conference featured 5 presentations, of which 2 have been catalogued separately for inclusion in this database. tabs., figs.

  19. The Dams and Monitoring Systems and Case Study: Ataturk and Karakaya Dams

    Science.gov (United States)

    Kalkan, Y.; Bilgi, S.; Gülnerman, A. G.

    2017-12-01

    Dams are among the most important engineering structures used for flood controls, agricultural purposes as well as drinking and hydroelectric power. Especially after the Second World War, developments on the construction technology, increase the construction of larger capacity dams. There are more than 150.000 dams in the world and almost 1000 dams in Turkey, according to international criteria. Although dams provide benefits to humans, they possess structural risks too. To determine the performance of dams on structural safety, assessing the spatial data is very important. These are movement, water pressure, seepage, reservoir and tail-water elevations, local seismic activities, total pressure, stress and strain, internal concrete temperature, ambient temperature and precipitation. These physical data are measured and monitored by the instruments and equipment. Dams and their surroundings have to be monitored by using essential methods at periodic time intervals in order to determine the possible changes that may occur over the time. Monitoring programs typically consist of; surveillance or visual observation. These programs on dams provide information for evaluating the dam's performance related to the design intent and expected changes that could affect the safety performance of the dam. Additionally, these programs are used for investigating and evaluating the abnormal or degrading performance where any remedial action is necessary. Geodetic and non-geodetic methods are used for monitoring. Monitoring the performance of the dams is critical for producing and maintaining the safe dams. This study provides some general information on dams and their different monitoring systems by taking into account two different dams and their structural specifications with the required information. The case study in this paper depends on a comparison of the monitoring surveys on Atatürk Dam and Karakaya Dam, which are constructed on Firat River with two different structural

  20. Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy.

    Science.gov (United States)

    Zimmer, Dana; Kruse, Jens; Baum, Christel; Borca, Camelia; Laue, Michael; Hause, Gerd; Meissner, Ralph; Leinweber, Peter

    2011-09-01

    Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between As and Fe was explained by the different sorption/desorption properties of As(III) and As(V). The Cu and Zn intensities were not associated with the intensity of Fe in the plaque, which seems to be a willow-specific difference compared to other wetland plants. These results suggested that willows are especially suited to stabilize low-phytoextractable elements like Cu and As in their roots and rhizosphere. Thus, short rotation coppicing of willows may be a practical approach to mitigate the adverse effects of floodplain soil contamination. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. A comparison of the suitability of different willow varieties to treat on-site wastewater effluent in an Irish climate.

    Science.gov (United States)

    Curneen, S J; Gill, L W

    2014-01-15

    Short rotation coppiced willow trees can be used to treat on-site wastewater effluent with the advantage that, if planted in a sealed basin and sized correctly, they produce no effluent discharge. This paper has investigated the evapotranspiration rate of four different willow varieties while also monitoring the effects of three different effluent types on each variety. The willow varieties used are all cultivars of Salix viminalis. The effluents applied were primary (septic tank) effluent, secondary treated effluent and rain water (control). The results obtained showed that the addition of effluent had a positive effect on the evapotranspiration. The willows were also found to uptake a high proportion of the nitrogen and phosphorus from the primary and secondary treated effluents added during the first year. The effect of the different effluents on the evapotranspiration rate has been used to design ten full scale on-site treatment systems which are now being monitored. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Variation in copper and zinc tolerance and accumulation in 12 willow clones: implications for phytoextraction*

    Science.gov (United States)

    Yang, Wei-dong; Wang, Yu-yan; Zhao, Feng-liang; Ding, Zhe-li; Zhang, Xin-cheng; Zhu, Zhi-qiang; Yang, Xiao-e

    2014-01-01

    Willows (Salix spp.) have shown high potential for the phytoextraction of heavy metals. This study compares variations in copper (Cu) and zinc (Zn) tolerance and accumulation potential among 12 willow clones grown in a nutrient solution treated with 50 μmol/L of Cu or Zn, respectively. The results showed differences in the tolerance and accumulation of Cu and Zn with respect to different species/clones. The biomass variation among clones in response to Cu or Zn exposure ranged from the stimulation of growth to inhibition, and all of the clones tested showed higher tolerance to Cu than to Zn. The clones exhibited less variation in Cu accumulation but larger variation in Zn accumulation. Based on translocation factors, it was found that most of the Cu was retained in the roots and that Zn was more mobile than Cu for all clones. It is concluded that most willow clones are good accumulators of Zn and Cu. PMID:25183033

  3. Cadmium concentrations in tissues of willow ptarmigan (Lagopus lagopus) and rock ptarmigan (Lagopus muta) in Nunavik, Northern Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigue, Jean [Environment Canada, Service canadien de la faune, 1141 route de l' Eglise, Sainte-Foy, Quebec, G1V 4H5 (Canada)]. E-mail: jean.rodrigue@ec.gc.ca; Champoux, Louise [Environment Canada, Service canadien de la faune, 1141 route de l' Eglise, Sainte-Foy, Quebec, G1V 4H5 (Canada); Leclair, Daniel [Centre de recherche du Nunavik, Societe Makivik, C.P. 179, Kuujjuaq, Quebec, J0M 1C0 (Canada); Duchesne, Jean-Francois [Unite de recherche en sante publique du CHUQ, 945, avenue Wolfe, Sainte-Foy, Quebec, G1V 5B3 (Canada)

    2007-06-15

    Willow and rock ptarmigan were obtained from Northern Quebec. Willow ptarmigan were found to have mean cadmium concentrations of 179.7 {mu}g/g (dw) in the kidneys and 25.8 {mu}g/g (dw) in the liver; these levels were three times higher than those found in the rock ptarmigan. The cadmium levels in the ptarmigan were below the threshold above which adverse effects can be observed in birds. The difference between the two ptarmigan species in cadmium content is explained by the diet. A comparison of their diet showed that willow, which stores cadmium, is an important food resource for willow ptarmigan but not for rock ptarmigan. Because there is limited information available on the consumption of ptarmigan kidneys and liver by the Inuit, and the fact that this is a traditional way of life and provides nutritional benefits to the Inuit population, no consumption guidelines are proposed. - High levels of cadmium were found in ptarmigan in Northern Quebec. No consumption guidelines are proposed for the Inuit people.

  4. Cadmium concentrations in tissues of willow ptarmigan (Lagopus lagopus) and rock ptarmigan (Lagopus muta) in Nunavik, Northern Quebec

    International Nuclear Information System (INIS)

    Rodrigue, Jean; Champoux, Louise; Leclair, Daniel; Duchesne, Jean-Francois

    2007-01-01

    Willow and rock ptarmigan were obtained from Northern Quebec. Willow ptarmigan were found to have mean cadmium concentrations of 179.7 μg/g (dw) in the kidneys and 25.8 μg/g (dw) in the liver; these levels were three times higher than those found in the rock ptarmigan. The cadmium levels in the ptarmigan were below the threshold above which adverse effects can be observed in birds. The difference between the two ptarmigan species in cadmium content is explained by the diet. A comparison of their diet showed that willow, which stores cadmium, is an important food resource for willow ptarmigan but not for rock ptarmigan. Because there is limited information available on the consumption of ptarmigan kidneys and liver by the Inuit, and the fact that this is a traditional way of life and provides nutritional benefits to the Inuit population, no consumption guidelines are proposed. - High levels of cadmium were found in ptarmigan in Northern Quebec. No consumption guidelines are proposed for the Inuit people

  5. Island development impacts on the Nile River morphology

    Directory of Open Access Journals (Sweden)

    Nahla Sadek

    2013-03-01

    Full Text Available The greater Cairo area has many islands formed after the Aswan High Dam construction. Ministry of water resources and irrigation is interested in studying the development and evolution of these islands in order to reflect the esthetic aspects and improvement of the environment surrounding the islands. This study focuses on Shubra El-Khaima Island which is located upstream Delta Barrage in the back water curve region. The study aims to propose different alternatives for island development. GSTAR3.0 model is the most recent version of a series of numerical models for simulating flow of water and sediment transport and prediction of morphological changes in alluvial rivers. This model was used to simulate and examine different alternatives for Shubra island development on river morphology according to different discharges scenarios. The optimum alternative was proposed. Also, the future required precautions to mitigate the effects of this development on the stability of watercourse were suggested.

  6. Uptake, accumulation and metabolic response of ferricyanide in weeping willows.

    Science.gov (United States)

    Yu, Xiao-Zhang; Gu, Ji-Dong

    2009-01-01

    The remediation potential and metabolic responses of plants to ferricyanide were investigated using pre-rooted weeping willows (Salix babylonica L.) grown hydroponically in growth chambers and treated with potassium ferricyanide. Positive responses were observed for the plants exposed to cyanide recovered in plant biomass was constant in all treatments, indicating that transport is a major limiting step for the uptake of ferricyanide by plants. The majority of the ferricyanide taken up from the growth media was possibly assimilated during transport through plants. The velocity of the removal processes can be described by Michaelis-Menten kinetics, and the half-saturation constant (K(M)) and the maximum removal capacity (v(max)) were estimated to be 228.1 mg CN L(-1) and 36.43 mg CN kg(-1) d(-1), respectively, using non-linear regression methods. These results suggest that weeping willows can take up, transport and assimilate ferricyanide; and phytoremediation is an option for cleaning up the environmental sites contaminated with cyanide complexes.

  7. Research on Safety Factor of Dam Slope of High Embankment Dam under Seismic Condition

    Directory of Open Access Journals (Sweden)

    Li Bin

    2015-01-01

    Full Text Available With the constant development of construction technology of embankment dam, the constructed embankment dam becomes higher and higher, and the embankment dam with its height over 200m will always adopt the current design criteria of embankment dam only suitable for the construction of embankment dam lower than 200m in height. So the design criteria of high embankment dam shall be improved. We shall calculate the stability and safety factors of dam slope of high embankment dam under different dam height, slope ratio and different seismic intensity based on ratio of safety margin, and clarify the change rules of stability and safety factors of dam slope of high embankment dam with its height over 200m. We calculate the ratio of safety margin of traditional and reliable method by taking the stable, allowable and reliability index 4.2 of dam slope of high embankment dam with its height over 200m as the standard value, and conduct linear regression for both. As a result, the conditions, where 1.3 is considered as the stability and safety factors of dam slope of high embankment dam with its height over 200m under seismic condition and 4.2 as the allowable and reliability index, are under the same risk control level.

  8. With willows and poplars against the heavy metals

    International Nuclear Information System (INIS)

    Jaros, M.

    2002-01-01

    Special kinds of trees take out cadmium, lead and zinc from the soil, helping its rehabilitation in contaminated regions. A new method for soil rehabilitation (phytoremediation) based on plants is described. Special willows and poplars have the capability to extract as a sponge heavy metals from the soils and store them in their leaves. For example, they can uptake 700 times the amount of cadmium than the normal plants do. (nevyjel)

  9. Environmental life cycle assessment of producing willow, alfalfa and straw from spring barley as feedstocks for bioenergy or biorefinery systems

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Knudsen, Marie Trydeman; Djomo, Sylvestre Njakou

    2017-01-01

    The current study aimed at evaluating potential environmental impacts for the production of willow, alfalfa and straw from spring barley as feedstocks for bioenergy or biorefinery systems. A method of Life Cycle Assessment was used to evaluate based on the following impact categories: Global...... and land occupation. Environmental impacts for straw were economically allocated from the impacts obtained for spring barley. The results obtained per ton dry matter showed a lower carbon footprint for willow and alfalfa compared to straw. It was due to higher soil carbon sequestration and lower N2O...... emissions. Likewise, willow and alfalfa had lower EP than straw. Straw had lowest NRE use compared to other biomasses. PFWTox was lower in willow and alfalfa compared to straw. A critical negative effect on soil quality was found with the spring barley production and hence for straw. Based on the energy...

  10. Dams designed to fail

    Energy Technology Data Exchange (ETDEWEB)

    Penman, A. [Geotechnical Engineering Consultants, Harpenden (United Kingdom)

    2004-09-01

    New developments in geotechnical engineering have led to methods for designing and constructing safe embankment dams. Failed dams can be categorized as those designed to fail, and those that have failed unexpectedly. This presentation outlined 3 dam failures: the 61 m high Malpasset Dam in France in 1959 which killed 421; the 71 m high Baldwin Hills Dam in the United States in 1963 which killed 5; and, the Vajont Dam in Italy in 1963 which killed 2,600 people. Following these incidents, the International Commission for Large Dams (ICOLD) reviewed regulations on reservoir safety. The 3 dams were found to have inadequate spillways and their failures were due to faults in their design. Fuse plug spillways, which address this problem, are designed to fail if an existing spillway proves inadequate. They allow additional discharge to prevent overtopping of the embankment dam. This solution can only be used if there is an adjacent valley to take the additional discharge. Examples of fuse gates were presented along with their effect on dam safety. A research program is currently underway in Norway in which high embankment dams are being studied for overtopping failure and failure due to internal erosion. Internal erosion has been the main reason why dams have failed unexpectedly. To prevent failures, designers suggested the use of a clay blanket placed under the upstream shoulder. However, for dams with soft clay cores, these underblankets could provide a route for a slip surface and that could lead to failure of the upstream shoulder. It was concluded that a safe arrangement for embankment dams includes the use of tipping gates or overturning gates which always fail at a required flood water level. Many have been installed in old and new dams around the world. 14 refs., 19 figs.

  11. "The Wind in the Willows" and the Style of Romance

    Science.gov (United States)

    Gill, R. B.

    2012-01-01

    The style of Kenneth Grahame's "The Wind in the Willows" arises from an alternative vision and choice of values characteristic of romance. Romance seeks fulfillment beyond the consequences of everyday relationships and the constrictions of ordinary life. Causal relationships give way to lists of independent items, unmotivated outcomes, and…

  12. Potential benefits of commercial willow Short Rotation Coppice (SRC) for farm-scale plant and invertebrate communities in the agri-environment

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Rebecca L.; Hanley, Mick E.; Goulson, Dave; Clarke, Donna J.; Doncaster, C. Patrick; Taylor, Gail [University of Southampton, Faculty of Natural and Environmental Sciences, Life Sciences Building, Southampton, S017 1BJ (United Kingdom)

    2011-01-15

    The cultivation of bioenergy crops (BECs) represents a significant land-use change in agri-environments, but their deployment has raised important issues globally regarding possible impacts on biodiversity. Few studies however, have systematically examined the effect of commercial scale bioenergy plantations on biodiversity in agri-ecosystems. In this study we investigate how the abundance and diversity of two key components of farmland biodiversity (ground flora and winged invertebrates) varied between mature willow Short Rotation Coppice (SRC) and two alternative land-use options (arable crops and set-aside land). Although the abundance of winged invertebrates was similar across all land-uses, taxonomic composition varied markedly. Hymenoptera and large Hemiptera (>5 mm) were more abundant in willow SRC than in arable or set-aside. Similarly although plant species richness was greater in set-aside, our data show that willow SRC supports a different plant community to the other land-uses, being dominated by competitive perennial species such as Elytrigia repens and Urtica dioica. Our results suggest that under current management practices a mixed farming system incorporating willow SRC can benefit native farm-scale biodiversity. In particular the reduced disturbance in willow SRC allows the persistence of perennial plant species, potentially providing a stable refuge and food sources for invertebrates. In addition, increased Hymenoptera abundance in willow SRC could potentially have concomitant effects on ecosystem processes, as many members of this Order are important pollinators of crop plants or otherwise fulfil an important beneficial role as predators or parasites of crop pests. (author)

  13. Pathogenic and Ice-Nucleation Active (INA) Bacteria causing Dieback of Willows in Short Rotation Forestry

    Energy Technology Data Exchange (ETDEWEB)

    Nejad, Pajand

    2005-03-01

    To find out whether bacteria isolated from diseased plant parts can be the main causal agent for the dieback appearing in Salix energy forestry plantations in Sweden during the last few years, and if the joint effects of bacteria and frost injury are synergistic, extensive sampling of shoots from diseased Salix plants was performed. We performed several laboratory and greenhouse investigations and used evaluation techniques on the functions of the Ice-Nucleation Active (INA) bacteria. We carried out a comparison between spring and autumn bacterial communities isolated from within (endophytically) and surface (epiphytically) plant tissues of Salix viminalis. Seasonal variation of bacteria in willow clones with different levels of frost sensitivity and symptoms of bacterial damage was also investigated. We further focussed on possible effect of fertilisation and nutrient availability on the bacterial community in relation to plant dieback in Estonian willow plantations. The identification and detection of INA bacteria which cause damage in combination with frost to willow (Salix spp) plants in late fall, winter and spring was performed using BIOLOG MicroPlate, biochemical tests, selective INA primers and 16S rDNA analysis. To distinguish the character for differentiation between these bacteria morphologically and with respect to growing ability different culture media were used. We studied the temperature, at which ice nucleation occurred for individual bacteria, estimated the population of INA bacteria, effect of growth limiting factors, and evaluated the effect of chemical and physical agents for disruption and possible inhibition of INA among individual bacterial strains. The concentration of carbon, nitrogen and phosphorus on INA is discussed. We demonstrate that among the bacterial isolates recovered from the willow plantations, there were many that were capable of ice nucleation at temperatures between -2 and -10 deg C, many that were capable of inducing a

  14. The Willow Microbiome is Influenced by Soil Petroleum-Hydrocarbon Concentration with Plant Compartment-Specific Effects

    Directory of Open Access Journals (Sweden)

    Stacie Tardif

    2016-09-01

    Full Text Available The interaction between plants and microorganisms, which is the driving force behind the decontamination of petroleum hydrocarbon (PHC contamination in phytoremediation technology, is poorly understood. Here, we aimed at characterizing the variations between plant compartments in the microbiome of two willow cultivars growing in contaminated soils. A field experiment was set-up at a former petrochemical plant in Canada and, after two growing seasons, bulk soil, rhizosphere soil, roots and stems samples of two willow cultivars (Salix purpurea cv. FishCreek and Salix miyabeana cv. SX67 growing at three PHC contamination concentrations were taken. DNA was extracted and bacterial 16S rRNA gene and fungal internal transcribed spacer (ITS regions were amplified and sequenced using an Ion Torrent Personal Genome Machine. Following multivariate statistical analyses, the level of PHC-contamination appeared as the primary factor influencing the willow microbiome with compartment-specific effects, with significant differences between the responses of bacterial and fungal communities. Increasing PHC contamination levels resulted in shifts in the microbiome composition, favoring putative hydrocarbon degraders and microorganisms previously reported as associated with plant health. These shifts were less drastic in the rhizosphere, root and stem tissues as compared to bulk soil, probably because the willows provided a more controlled environment and thus protected microbial communities against increasing contamination levels. Insights from this study will help to devise optimal plant microbiomes for increasing the efficiency of phytoremediation technology.

  15. 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.

  16. Energy balance and evaporation of a short-rotation willow forest. Variation with season and stand development

    Energy Technology Data Exchange (ETDEWEB)

    Iritz, Z.

    1996-10-01

    Energy balance and evaporation of a short-rotation willow (Salix viminalis L.) forest was studied in relation to season and stand development. The developmental stage of the forest stand considerably influenced how the energy, received as net radiation, was partitioned between the connective fluxes and the storage components. The main part of the available energy was utilised for evaporation during most of the season. Only at the beginning of the season did the willow forest supply heat to the atmosphere. Later in the season, energy was taken from air and utilised for evaporation, which resulted in negative sensible heat fluxes. Soil heat storage was also a significant term in the energy balance and also strongly depended on canopy development. Changes in energy partitioning relative to leaf area indices indicated the existence of a threshold value for leaf area index of the developing canopy. The analysis suggested that the canopy of the willow forest could be considered as closed at a leaf area index of 2. It was further found that evaporation from well-irrigated willow forest occurred also during night-time, particularly in windy and dry weather conditions. The sources of nocturnal evaporation were both the canopy, i.e. indicating non-closed stomata, and the soil surface. Partitioning of the total evaporation into components was investigated using a physically-based model with a two-layer aboveground representation and a two-layer soil module. The model estimates evaporation with respect to developmental stage of the willow stand and also takes into account the interaction between the fluxes from the canopy and the soil surface. Good performance of the model indicated that, after further testing in drier conditions, it could be used as a tool for analysing the prerequisites for energy-forest establishment, and practical management of energy forest stands. 37 refs, 9 figs

  17. Evaluating safety of concrete gravity dam on weak rock: Scott Dam

    International Nuclear Information System (INIS)

    Goodman, R.E.; Ahlgren, C.S.

    2000-01-01

    Scott Dam is owned and operated by Pacific Gas and Electric Co. (PG and E) as part of the Potter Valley Project. Although it is an unimpressive concrete gravity dam [233 m (765 ft) long with maximum water surface 33.4 m (110 ft) above tail water], the dam has unusually complex and weak foundation rocks; thick condition caused design changes during construction, numerous subsequent special investigations, and several corrections and additions. A main stumbling block to clarification of the dam safety issue for Scott Dam has always been difficulty in characterizing the foundation material. This paper discusses an approach to this problem as well s how the safety of the dam was subsequently confirmed. Following a comprehensive program of research, investigations, and analysis from 1991 to 1997

  18. Genetic variation in the endangered Southwestern Willow Flycatcher

    Science.gov (United States)

    Busch, Joseph; Miller, Mark P.; Paxton, E.H.; Sogge, M.K.; Keim, Paul

    2000-01-01

    The Southwestern Willow Flycatcher (Empidonax traillii extimus) is an endangered Neotropical migrant that breeds in isolated remnants of dense riparian habitat in the southwestern United States. We estimated genetic variation at 20 breeding sites of the Southwestern Willow Flycatcher (290 individuals) using 38 amplified fragment length polymorphisms (AFLPs). Our results suggest that considerable genetic diversity exists within the subspecies and within local breeding sites. Statistical analyses of genetic variation revealed only slight, although significant, differentiation among breeding sites (Mantel's r = 0.0705, P UPGMA cluster analysis of the AFLP markers indicates that extensive gene flow has occurred among breeding sites. No one site stood out as being genetically unique or isolated. Therefore, the small level of genetic structure that we detected may not be biologically significant. Ongoing field studies are consistent with this conclusion. Of the banded birds that were resighted or recaptured in Arizona during the 1996 to 1998 breeding seasons, one-third moved between breeding sites and two-thirds were philopatric. Low differentiation may be the result of historically high rangewide diversity followed by recent geographic isolation of breeding sites, although observational data indicate that gene flow is a current phenomenon. Our data suggest that breeding groups of E. t. extimus act as a metapopulation.

  19. Woody lianas increase in dominance and maintain compositional integrity across an Amazonian dam-induced fragmented landscape.

    Directory of Open Access Journals (Sweden)

    Isabel L Jones

    Full Text Available Tropical forest fragmentation creates insular biological communities that undergo species loss and changes in community composition over time, due to area- and edge-effects. Woody lianas thrive in degraded and secondary forests, due to their competitive advantage over trees in these habitats. Lianas compete both directly and indirectly with trees, increasing tree mortality and turnover. Despite our growing understanding of liana-tree dynamics, we lack detailed knowledge of the assemblage-level responses of lianas themselves to fragmentation, particularly in evergreen tropical forests. We examine the responses of both sapling and mature liana communities to landscape-scale forest insularization induced by a mega hydroelectric dam in the Brazilian Amazon. Detailed field inventories were conducted on islands created during reservoir filling, and in nearby mainland continuous forest. We assess the relative importance of variables associated with habitat fragmentation such as area, isolation, surrounding forest cover, fire and wind disturbance, on liana community attributes including abundance, basal area, diversity, and composition. We also explore patterns of liana dominance relative to tree saplings and adults ≥10 cm diameter at breast height. We find that 1 liana community composition remains remarkably similar across mainland continuous forest and islands, regardless of extreme area- and edge- effects and the loss of vertebrate dispersers in the latter; and 2 lianas are increasing in dominance relative to trees in the sapling layer in the most degraded islands, with both the amount of forest cover surrounding islands and fire disturbance history predicting liana dominance. Our data suggest that liana communities persist intact in isolated forests, regardless of extreme area- and edge-effects; while in contrast, tree communities simultaneously show evidence of increased turnover and supressed recruitment. These processes may lead to lianas

  20. Woody lianas increase in dominance and maintain compositional integrity across an Amazonian dam-induced fragmented landscape.

    Science.gov (United States)

    Jones, Isabel L; Peres, Carlos A; Benchimol, Maíra; Bunnefeld, Lynsey; Dent, Daisy H

    2017-01-01

    Tropical forest fragmentation creates insular biological communities that undergo species loss and changes in community composition over time, due to area- and edge-effects. Woody lianas thrive in degraded and secondary forests, due to their competitive advantage over trees in these habitats. Lianas compete both directly and indirectly with trees, increasing tree mortality and turnover. Despite our growing understanding of liana-tree dynamics, we lack detailed knowledge of the assemblage-level responses of lianas themselves to fragmentation, particularly in evergreen tropical forests. We examine the responses of both sapling and mature liana communities to landscape-scale forest insularization induced by a mega hydroelectric dam in the Brazilian Amazon. Detailed field inventories were conducted on islands created during reservoir filling, and in nearby mainland continuous forest. We assess the relative importance of variables associated with habitat fragmentation such as area, isolation, surrounding forest cover, fire and wind disturbance, on liana community attributes including abundance, basal area, diversity, and composition. We also explore patterns of liana dominance relative to tree saplings and adults ≥10 cm diameter at breast height. We find that 1) liana community composition remains remarkably similar across mainland continuous forest and islands, regardless of extreme area- and edge- effects and the loss of vertebrate dispersers in the latter; and 2) lianas are increasing in dominance relative to trees in the sapling layer in the most degraded islands, with both the amount of forest cover surrounding islands and fire disturbance history predicting liana dominance. Our data suggest that liana communities persist intact in isolated forests, regardless of extreme area- and edge-effects; while in contrast, tree communities simultaneously show evidence of increased turnover and supressed recruitment. These processes may lead to lianas becoming a dominant

  1. Differential effects of glyphosate and aminomethylphosphonic acid (AMPA) on photosynthesis and chlorophyll metabolism in willow plants.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Maccario, Sophie; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-06-01

    We used a willow species (Salix miyabeana cultivar SX64) to examine the differential secondary-effects of glyphosate and aminomethylphosphonic acid (AMPA), the principal glyphosate by-product, on chlorophyll metabolism and photosynthesis. Willow plants were treated with different concentrations of glyphosate (equivalent to 0, 1.4, 2.1 and 2.8kgha(-1)) and AMPA (equivalent to 0, 0.28, 1.4 and 2.8kgha(-1)) and evaluations of pigment contents, chlorophyll fluorescence, and oxidative stress markers (hydrogen peroxide content and antioxidant enzyme activities) in leaves were performed after 12h of exposure. We observed that AMPA and glyphosate trigger different mechanisms leading to decreases in chlorophyll content and photosynthesis rates in willow plants. Both chemicals induced ROS accumulation in willow leaves although only glyphosate-induced oxidative damage through lipid peroxidation. By disturbing chlorophyll biosynthesis, AMPA induced decreases in chlorophyll contents, with consequent effects on photosynthesis. With glyphosate, ROS increases were higher than the ROS-sensitive threshold, provoking chlorophyll degradation (as seen by pheophytin accumulation) and invariable decreases in photosynthesis. Peroxide accumulation in both AMPA and glyphosate-treated plants was due to the inhibition of antioxidant enzyme activities. The different effects of glyphosate on chlorophyll contents and photosynthesis as described in the literature may be due to various glyphosate:AMPA ratios in those plants. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Dam removal: Listening in

    Science.gov (United States)

    Foley, M. M.; Bellmore, J. R.; O'Connor, J. E.; Duda, J. J.; East, A. E.; Grant, G. E.; Anderson, C. W.; Bountry, J. A.; Collins, M. J.; Connolly, P. J.; Craig, L. S.; Evans, J. E.; Greene, S. L.; Magilligan, F. J.; Magirl, C. S.; Major, J. J.; Pess, G. R.; Randle, T. J.; Shafroth, P. B.; Torgersen, C. E.; Tullos, D.; Wilcox, A. C.

    2017-07-01

    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 (< 5 years) and do not adequately represent the diversity of dam types, watershed conditions, and dam-removal methods in the U.S.

  3. Public safety around dams

    Energy Technology Data Exchange (ETDEWEB)

    Bourassa, H. [Centre d' expertise hydrique du Quebec, Quebec, PQ (Canada)

    2009-07-01

    Fourty public dams are managed on a real-time basis by the Centre d'expertise hydrique du Quebec (CEHQ). This presentation described the public dams owned by the CEHQ and discussed the public safety measures at the dams. The dams serve various purposes, including protection against floods; industrial or drinking water supply; resort or recreational activities; hydroelectric development; and wildlife conservation. Trigger events were also discussed, such as the complaint at Rapides-des-Cedres dam and deaths that occurred in 2004 when water from a dam was released without warning. Several photographs were presented to illustrate that people were unaware of the danger. Initiatives aimed at raising awareness and studying public safety issues were discussed. A pilot project was launched and a permanent committee was created to evaluate all aspects of public safety at the dams owned by CEHQ. The first tasks of the committee were to establish requirements for waterway safety barriers, both upstream and downstream, for all public dams; to establish requirements for safety signage for all public dams; and to develop criteria to decide on safety signage at each dam. figs.

  4. Public safety around dams

    Energy Technology Data Exchange (ETDEWEB)

    Bourassa, H [Centre d' expertise hydrique du Quebec, Quebec, PQ (Canada)

    2009-07-01

    Fourty public dams are managed on a real-time basis by the Centre d'expertise hydrique du Quebec (CEHQ). This presentation described the public dams owned by the CEHQ and discussed the public safety measures at the dams. The dams serve various purposes, including protection against floods; industrial or drinking water supply; resort or recreational activities; hydroelectric development; and wildlife conservation. Trigger events were also discussed, such as the complaint at Rapides-des-Cedres dam and deaths that occurred in 2004 when water from a dam was released without warning. Several photographs were presented to illustrate that people were unaware of the danger. Initiatives aimed at raising awareness and studying public safety issues were discussed. A pilot project was launched and a permanent committee was created to evaluate all aspects of public safety at the dams owned by CEHQ. The first tasks of the committee were to establish requirements for waterway safety barriers, both upstream and downstream, for all public dams; to establish requirements for safety signage for all public dams; and to develop criteria to decide on safety signage at each dam. figs.

  5. High yielding biomass genotypes of willow (Salix spp.) show differences in below ground biomass allocation

    International Nuclear Information System (INIS)

    Cunniff, Jennifer; Purdy, Sarah J.; Barraclough, Tim J.P.; Castle, March; Maddison, Anne L.; Jones, Laurence E.; Shield, Ian F.; Gregory, Andrew S.; Karp, Angela

    2015-01-01

    Willows (Salix spp.) grown as short rotation coppice (SRC) are viewed as a sustainable source of biomass with a positive greenhouse gas (GHG) balance due to their potential to fix and accumulate carbon (C) below ground. However, exploiting this potential has been limited by the paucity of data available on below ground biomass allocation and the extent to which it varies between genotypes. Furthermore, it is likely that allocation can be altered considerably by environment. To investigate the role of genotype and environment on allocation, four willow genotypes were grown at two replicated field sites in southeast England and west Wales, UK. Above and below ground biomass was intensively measured over two two-year rotations. Significant genotypic differences in biomass allocation were identified, with below ground allocation differing by up to 10% between genotypes. Importantly, the genotype with the highest below ground biomass also had the highest above ground yield. Furthermore, leaf area was found to be a good predictor of below ground biomass. Growth environment significantly impacted allocation; the willow genotypes grown in west Wales had up to 94% more biomass below ground by the end of the second rotation. A single investigation into fine roots showed the same pattern with double the volume of fine roots present. This greater below ground allocation may be attributed primarily to higher wind speeds, plus differences in humidity and soil characteristics. These results demonstrate that the capacity exists to breed plants with both high yields and high potential for C accumulation. - Highlights: • SRC willows are a source of biomass and act as carbon (C) sinks. • Biomass allocation was measured in 4 willow genotypes grown in two UK field sites. • The greatest yielding genotype had the greatest below ground biomass at both sites. • Below ground biomass allocation differed by up to 10% between genotypes and 94% between sites. • Environment e.g. wind

  6. Evaluating the impact of three incentive programs on the economics of cofiring willow biomass with coal in New York State

    International Nuclear Information System (INIS)

    Tharakan, P.J.; Volk, T.A.; Lindsey, C.A.; Abrahamson, L.P.; White, E.H.

    2005-01-01

    Plantations of fast-growing willow shrubs are being promoted as a source quality biomass feedstock for bioenergy and bioproducts in New York State (NY). In the near-term, cofiring of the feedstock--in combination with other woody biomass--with coal in existing utility power boilers is considered to be the most promising conversion method for energy generation. Despite the clear technological viability and associated environmental benefits, cofiring of willow has not been widely adopted. The relatively high production cost of the willow feedstock, which is over twice that of coal, is the primary reason for this lack of interest. Taxes that account for some of the social costs of using coal and/or incentives that appropriate value for some of the social benefits of using willow are essential for eliminating most or the entire current price differential. This paper presents an integrated analysis of the economics of power generation from cofiring willow biomass feedstock with coal, from the perspective of the grower, aggregator and the power plant. Emphasis is placed on analyzing the relative impact of a green premium price, a closed-loop biomass tax credit, and payments to growers under the proposed Conservation Reserve Program (CRP) harvesting exemption policy. The CRP payments reduced the delivered cost of willow by 36-35%, to $1.90 GJ -1 and $1.70 GJ -1 , under current and increased yield conditions, respectively. These prices are still high, relative to coal. Other incentives are required to ensure commercial viability. The required levels of green premium price (0.4-1.0 cents kWh -1 ) and biomass tax credit (0.75-2.4 cents kWh -1 ) vary depending on whether the incentives were being applied by themselves or in combination, and whether current yield or potential increased yields were being considered. In the near term, cofiring willow biomass and coal can be an economically viable option for power generation in NY if the expected overall beneficial effects

  7. 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

  8. Predictive models of biomass for poplar and willow. Short rotation coppice in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Brewer, A.C.; Morgan, G.W.; Poole, E.J.; Baldwin, M.E.; Tubby, I. (Biometrics, Surveys and Statistics Division, Forest Research, Farnham (United Kingdom))

    2007-07-01

    A series of forty-nine experimental trials on short rotation coppice (SRC) were conducted throughout the United Kingdom using a selection of varieties of poplar and willow with the aim of evaluating their performance for wood fuel production under a representative range of UK conditions. Observations on the crops and on a range of site and climatic conditions during the growth of the crops were taken over two three-year cutting cycles. These observations were used to develop a suite of empirical models for poplar and willow SRC growth and yield from which systems were constructed to provide a- priori predictions of biomass yield for any site in the UK with known characteristics (predictive yield models), and estimates of biomass yield from a standing crop (standing biomass models). The structure of the series of field trials and the consequent approach and methodology used in the construction of the suite of empirical models are described, and their use in predicting biomass yields of poplar and willow SRC is discussed. (orig.)

  9. Baseline element concentrations in soils and plants, Wattenmeer National Park, North and East Frisian Islands, Federal Republic of Germany

    Science.gov (United States)

    Severson, R.C.; Gough, L.P.; van den Boom, G.

    1992-01-01

    Baseline element concentrations are given for dune grass (Ammophilia arenaria), willow (Salix repens), moss (Hylocomium splendens) and associated surface soils. Baseline and variability data for pH, ash, Al, As, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Se, Sr, Th, Ti, V, Y, Yb, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration between five Frisian Islands are given for each of the sample media. In general, only a few elements in each media showed statistically significant differences between the islands sampled. The measured concentrations in all sample media exhibited ranges that cannot be attributed to anthropogenic additions of trace elements, with the possible exception of Hg and Pb in surface soils.Baseline element concentrations are given for dune grass (Ammophilia arenaria), willow (Salix repens), moss (Hylocomium splendens) and associated surface soils. Baseline and variability data for pH, ash, Al, As, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Se, Sr, Th, Ti, V, Y, Yb, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration between five Frisian Islands are given for each of the sample media. In general, only a few elements in each media showed statistically significant differences between the islands sampled. The measured concentrations in all sample media exhibited ranges that cannot be attributed to anthropogenic additions of trace elements, with the possible exception of Hg and Pb in surface soils.

  10. Initial spacing of poplars and willows grown as arable coppice

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, A.; Johns, C.

    1997-11-01

    Two clones of poplar and two clones of willow were grown at two sites, on a three year cutting cycle, at six different square spacings, between 0.8 metres and 1.5 metres. The two willow clones 'Bowles hybrid' and 'Dasyclados' were planted at both sites. The poplar clones Populus interamericana 'Beaupre' and Populus trichocarpa 'Columbia River'' were planted at Wishanger in Hampshire. The poplar clones Populus interamericana 'Boelare' and Populus trichocarpa 'Trichobel' were planted at Downham Market in Norfolk. The highest yield of 17.55 oven dry tonnes per hectare (odt/ha/annum) was obtained from 'Bowles hybrid', at the closest spacing, grown on a water meadow adjacent to the River Wey at Wishanger. The highest yield for all clones at both sites was achieved at the closest spacing (in this first rotation). There was a significant linear effect. One of the most interesting observations was that when comparing the gradient of the linear relationship, within species, the gradient was steeper for the higher yielding clone. This was particularly so for the willows. This would suggest that higher yielding clones are more tolerant of crowding, or, that upright Salix viminalis make better use of close space than the more spreading Salix dasyclados. The new Salix x Salix schwerinnii hybrids should therefore also be responsive to closer spacing. The same effect was observed for the poplars at Wishanger only, but the difference was not as dramatic. There was a suggestion from the highest yielding poplar plots that optimum yield may still be obtained at the currently recommended spacing of 1.0 metre x 1.0 metre. (author)

  11. Wastewater purification in a willow plantation. The case study at Aarike

    International Nuclear Information System (INIS)

    Kuusemets, V.; Mauring, T.

    1996-01-01

    In order to combine wastewater purification and biomass production for energy purposes, a willow plantation for wastewater treatment was established in 1995 in Aarike, Southern Estonia. Wastewater from a dwelling house (25 person equivalents, pe) is treated in a combined free-water filter system consisting of three separate basins, isolated with clay and having filter beds of gravel and sand mixture. The beds were planted with Salix viminalis. At the end of the first growing season, the purification efficiency of the newly established treatment system was 65% for BOD 7 , 43% for nitrogen and 11% for phosphorus removal. At the end of the establishment year, the above ground production of willow stems (bark and wood) and leaves was 1.3 and 0.3 t ha -1 , respectively. The figures are about three to five times higher than those recorded in previously established energy forest plantations of comparable ages in Estonia. 15 refs, 2 figs

  12. Teton Dam failure

    Energy Technology Data Exchange (ETDEWEB)

    Snorteland, N. [United States Dept. of the Interior, Washington, DC (United States). Bureau of Reclamation

    2009-07-01

    This case summary discussed an internal erosion failure that occurred at the embankment foundation of Teton Dam. The project was designed as a run-of-the-river power generation facility and to provide irrigation, flood protection, and power generation to the lower Teton region of southern Idaho. The dam site was located next to the eastern Snake River plain, a volcanic filled depression. The foundation's cutoff trench was excavated into the bedrock along the length of the dam. The dam was designed as a zoned earthfill with a height of 305 feet. A trench made of low plasticity windblown silt was designed to connect the embankment core to the rock foundation. Seeps were noted in 1976, and a leak was observed near the toe of the dam. A wet spot appeared on the downstream face of the dam at elevation 5200. A sinkhole then developed. The embankment crest collapsed, and the dam breached. Peak outflow was estimated at 1,000,000 cfs. The failure was attributed to a lack of communication between designers, a failure to understand geologic information about the region, and an insufficient review of designs and specifications by designers and field personnel. No monitoring instrumentation was installed in the embankment. Approximately 300 square miles were inundated, and 25,000 people were displaced. Eleven people were killed. A review group noted that the rock surface was not adequately sealed, and that the dam failed as a result of inadequate protection of the impervious core material from internal erosion. 42 figs.

  13. Sex- and habitat-specific responses of a high arctic willow, Salix arctica, to experimental climate change

    Energy Technology Data Exchange (ETDEWEB)

    Jones, M.H.; Macdonald, S.E. [Univ. of Alberta, Dept. of Renewable Resources, Edmonton, AB (Canada); Henry, G.H.R. [Univ. of British Columbia, Dept. of Geography, Vancouver, BC (Canada)

    1999-10-01

    Dioecious plant species and those occupying diverse habitats may present special analytical problems to researchers examining effects of climate change. Here we report the results from two complementary studies designed to determine the importance of sex and habitat on gas exchange and growth of male and female individuals of a dioecious, circumpolar willow, Salix arctica, in the Canadian High Arctic. In field studies, male and female willows from dry and wet habitats were subjected to passively enhanced summer temperature ({approx} to 1.3 deg C) using small open-top chambers over three years. Peak season gas exchange varied significantly by willow sex and habitat. Overall net assimilation was higher in the dry habitat than in the wet, and higher in females than in males. In the dry habitat, net assimilation of females was enhanced by experimental warming, but decreased in males. In the wet habitat, net assimilation of females was substantially depressed by experimental warming, while males showed an inconsistent response. Development and growth of male and female catkins were enhanced by elevated temperature more than leaf fascicles, but leaf fascicle development and growth varied more between the two habitats, particularly in males. In a controlled environment study, male and female willows from these same wet and dry habitats were grown in a 2x2 factorial experiment including 1 x or 2 x ambient [CO{sub 2}] and 5 or 12 deg. C. The sexes responded very differently to the experimental treatments, but we found no effect of original habitat. Net assimilation in males was affected by the interaction of temperature and CO{sub 2}, but in females by CO{sub 2} only. Our results demonstrate (a) significant intraspecific and intersexual differences in arctic willow physiology and growth, (b) that these differences are affected by environmental conditions expected to accompany global climate change, and (c) that sex- and habitat-specific responses should be explicitly

  14. How big of an effect do small dams have? Using geomorphological footprints to quantify spatial impact of low-head dams and identify patterns of across-dam variation

    Science.gov (United States)

    Fencl, Jane S.; Mather, Martha E.; Costigan, Katie H.; Daniels, Melinda D.

    2015-01-01

    Longitudinal connectivity is a fundamental characteristic of rivers that can be disrupted by natural and anthropogenic processes. Dams are significant disruptions to streams. Over 2,000,000 low-head dams (research and conservation is impaired by not knowing the magnitude of low-head dam impacts. Based on the geomorphic literature, we refined a methodology that allowed us to quantify the spatial extent of low-head dam impacts (herein dam footprint), assessed variation in dam footprints across low-head dams within a river network, and identified select aspects of the context of this variation. Wetted width, depth, and substrate size distributions upstream and downstream of six low-head dams within the Upper Neosho River, Kansas, United States of America were measured. Total dam footprints averaged 7.9 km (3.0–15.3 km) or 287 wetted widths (136–437 wetted widths). Estimates included both upstream (mean: 6.7 km or 243 wetted widths) and downstream footprints (mean: 1.2 km or 44 wetted widths). Altogether the six low-head dams impacted 47.3 km (about 17%) of the mainstem in the river network. Despite differences in age, size, location, and primary function, the sizes of geomorphic footprints of individual low-head dams in the Upper Neosho river network were relatively similar. The number of upstream dams and distance to upstream dams, but not dam height, affected the spatial extent of dam footprints. In summary, ubiquitous low-head dams individually and cumulatively altered lotic ecosystems. Both characteristics of individual dams and the context of neighboring dams affected low-head dam impacts within the river network. For these reasons, low-head dams require a different, more integrative, approach for research and management than the individualistic approach that has been applied to larger dams.

  15. Production of Probiotic Drink Using Pussy willow and Echium amoenum Extracts

    Directory of Open Access Journals (Sweden)

    Mahbobeh Eksiri

    2017-06-01

    Full Text Available Background and Objective: Nowadays, due to the lack of lactose and cholesterol, demand for consumption of non-dairy probiotic products is increasing. Probiotic drinks mixed with medicinal plant have great beneficial effect on human health. The main problems of non-dairy probiotic drinks are lack of nutrients for the growth of probiotics and bad taste of the product. The aim of this study was to produce a probiotic medicinal plant drink with favorable physicochemical, viability and sensory properties.Material and Methods: Probiotic drink prepared by Pussy willow and Echium amoenum extract (0.5 % w v-1, for each extract or together, Lactobacillus casei and Lactobacillus rhamnosus (108 CFU ml-1, individually and their combination. Glucose and whey powder (0.2% were used as a source of nutrition for the probiotics, and apple juice (20 and 30% was added to improve the taste of drink. The level of glucose was adjusted to reach the brix of 13 g100 g-1. Ascorbic acid (0.05% was used to improve micro-aerophilic conditions. The pH, acidity, glucose and viability of probiotic bacteria as well as the sensory properties of the prepared drink were investigated during 28 days at 4°C.Results and Conclusion: Based on the results, the treatment containing L. casei, Pussy willow, Echium amoenum and 30% apple juice due to the highest probiotic viability and the treatment containing Lactobacillus rhamnosus, Pussy willow, Echium amoenum and 30% apple juice because of higher total acceptance score, proper pH and acidity values were selected as the best treatments.Conflict of interest: The authors declare no conflict of interest.

  16. Mechanics of slide dams

    International Nuclear Information System (INIS)

    Young, G.A.

    1970-01-01

    Studies which promote the use of nuclear energy for peaceful projects in engineering are sponsored by the Atomic Energy Commission under the Plowshare program. Specific projects being considered include the construction of harbors, canals, and dams. Of these projects, perhaps the most difficult to accomplish will be the latter. This paper which is in two parts considers the problems which are associated with the construction of slide dams with nuclear explosives. It examines first the characteristics of conventional earth and rock-fill dams which are based upon proven techniques developed after many years of experience. The characteristics of natural landslide dams are also briefly considered to identify potential problems that must be overcome by slide dam construction techniques. Second, the mechanics of slide dams as determined from small-scale laboratory studies are presented. It is concluded that slide dams can be constructed and that small-scale field tests and additional laboratory studies are justified. (author)

  17. Mechanics of slide dams

    Energy Technology Data Exchange (ETDEWEB)

    Young, G A [Engineering, Agbabian-Jacobsen Associates, Los Angeles (United States)

    1970-05-15

    Studies which promote the use of nuclear energy for peaceful projects in engineering are sponsored by the Atomic Energy Commission under the Plowshare program. Specific projects being considered include the construction of harbors, canals, and dams. Of these projects, perhaps the most difficult to accomplish will be the latter. This paper which is in two parts considers the problems which are associated with the construction of slide dams with nuclear explosives. It examines first the characteristics of conventional earth and rock-fill dams which are based upon proven techniques developed after many years of experience. The characteristics of natural landslide dams are also briefly considered to identify potential problems that must be overcome by slide dam construction techniques. Second, the mechanics of slide dams as determined from small-scale laboratory studies are presented. It is concluded that slide dams can be constructed and that small-scale field tests and additional laboratory studies are justified. (author)

  18. Dam break analysis and flood inundation map of Krisak dam for emergency action plan

    Science.gov (United States)

    Juliastuti, Setyandito, Oki

    2017-11-01

    The Indonesian Regulation which refers to the ICOLD Regulation (International Committee on Large Dam required have the Emergency Action Plan (EAP) guidelines because of the dams have potential failure. In EAP guidelines there is a management of evacuation where the determination of the inundation map based on flood modeling. The purpose of the EAP is to minimize the risk of loss of life and property in downstream which caused by dam failure. This paper will describe about develop flood modeling and inundation map in Krisak dam using numerical methods through dam break analysis (DBA) using hydraulic model Zhong Xing HY-21. The approaches of dam failure simulation are overtopping and piping. Overtopping simulation based on quadrangular, triangular and trapezium fracture. Piping simulation based on cracks of orifice. Using results of DBA, hazard classification of Krisak dam is very high. The nearest village affected dam failure is Singodutan village (distance is 1.45 kilometer from dam) with inundation depth is 1.85 meter. This result can be used by stakeholders such as emergency responders and the community at risk in formulating evacuation procedure.

  19. Passage and survival probabilities of juvenile Chinook salmon at Cougar Dam, Oregon, 2012

    Science.gov (United States)

    Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Smith, Collin D.; Sprando, Jamie M.

    2014-01-01

    total of 92.2 percent of the treatment group passed through the RO during the November study and the RO was the only route open during the December study. The assumptions of the survival model were either met or adjusted for during each study. There was little evidence that tagger skill or premature failure of radio transmitters had an effect on survival estimates. There were statistically significant differences in travel times between treatment and control groups through several of the river reaches they had in common, but the differences were typically only a few hours, and the two groups likely experienced the same in-river conditions. There was direct evidence of bias due to detection of euthanized fish with live transmitters released as part of the study design. The bias was ameliorated by adjusting the survival estimates for the probability of detecting dead fish with live transmitters, which reduced the estimated survival probabilities by about 0.02. The data and models indicated that the treatment effect was not fully expressed until the study reach terminating with Marshall Island Park on the Willamette River, a distance of 105.8 kilometers downstream of Cougar Dam. This was the first reach in which the 95-percent confidence interval of the estimated reach-specific relative survival overlapped 1.0, indicating similar survival of treatment and control groups. The median travel time of the treatment group from release to Marshall Island Park was 1.64 days during the November study and 1.36 days during the December study. The survival probability of fish that passed into the RO was greater during the December study than during the November study. The relative survival probability of fish passing through the RO was 0.4594 (standard error [SE] 0.0543) during the November study and 0.7389 (SE 0.1160) during the December study. These estimates represent relative survival probabilities from release near Cougar Dam to the Marshall Island site. The estimated survival

  20. Spruce Lake Dam reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, G. [SGE Acres Ltd., Fredericton, NB (Canada); Barnard, J. [SGE Acres Ltd., St. John' s, NF (Canada); Vriezen, C. [City of Saint John, NF (Canada); Stephenson, M. [Jacques Whitford Environment Ltd., Fredericton, NB (Canada)

    2004-09-01

    Spruce Lake Dam was constructed in 1898 as part of the water supply system for Saint John, New Brunswick. The original dam was a 6 meter high, 140 meter long concrete gravity dam with an intake structure at its mid point and an overflow spillway at the left abutment. A rehabilitation project was launched in 2001 to bring the deteriorated dam into conformance with the dam safety guidelines of the Canadian Dam Association. The project criteria included minimal disruption to normal operation of water supply facilities and no negative effect on water quality. The project involved installation of a new low level outlet, removal of a gate house and water intake pipes, replacement of an access road culvert in the spillway channel, and raising the earth dam section by 1.8 meters to allow for increased water storage. The new raised section has an impervious core. The project also involved site and geotechnical investigations as well as hydrotechnical and environmental studies. This presentation described the final design of the remedial work and the environmental permitting procedures. Raising the operating level of the system proved successful as demonstrated by the fewer number of pumping days required after dam rehabilitation. The dam safety assessment under the Canadian Environmental Assessment Act began in April 2001, and the rehabilitation was completed by the end of 2002. 1 tab., 8 figs.

  1. The Study of Interactions between Active Compounds of Coffee and Willow (Salix sp. Bark Water Extract

    Directory of Open Access Journals (Sweden)

    Agata Durak

    2014-01-01

    Full Text Available Coffee and willow are known as valuable sources of biologically active phytochemicals such as chlorogenic acid, caffeine, and salicin. The aim of the study was to determine the interactions between the active compounds contained in water extracts from coffee and bark of willow (Salix purpurea and Salix myrsinifolia. Raw materials and their mixtures were characterized by multidirectional antioxidant activities; however, bioactive constituents interacted with each other. Synergism was observed for ability of inhibition of lipid peroxidation and reducing power, whereas compounds able to scavenge ABTS radical cation acted antagonistically. Additionally, phytochemicals from willow bark possessed hydrophilic character and thermostability which justifies their potential use as an ingredient in coffee beverages. Proposed mixtures may be used in the prophylaxis or treatment of some civilization diseases linked with oxidative stress. Most importantly, strong synergism observed for phytochemicals able to prevent lipids against oxidation may suggest protective effect for cell membrane phospholipids. Obtained results indicate that extracts from bark tested Salix genotypes as an ingredient in coffee beverages can provide health promoting benefits to the consumers; however, this issue requires further study.

  2. Uptake, removal, accumulation, and phytotoxicity of 4-chlorophenol in willow trees

    DEFF Research Database (Denmark)

    Ucisik, Ahmed Süheyl; Trapp, Stefan

    2008-01-01

    of implementing phytoremediation as a treatment method for 4-CP contamination was investigated. Willows were exposed to 4-CP levels ≤79.9 mg/L in hydroponic solution. The transpiration of the trees was used to determine toxic effects. Almost no inhibition of transpiration was detected at concentrations ≥15 mg...

  3. Natural islands and habitat islands as refuges of vegetation cover and wild bees. The case of the Lednica Landscape Park in western Poland

    Directory of Open Access Journals (Sweden)

    Banaszak Józef

    2016-03-01

    Full Text Available The study has contributed to the identification of the apifauna of central Wielkopolska. The study identified 161 bee species, accounting for 34.2% of the Polish bee fauna. The highest contribution (28.7% of the fauna comes from four species, namely Andrena haemorrhoa, A. helvola, Evylaeus calceatus and Osmia rufa, while Bombus terrestris and Evylaeus pauxillus are two subdominants. The assemblages of Apiformes in the study area are characterised by a significant contribution of spring-associated species, which is probably an effect of the presence of numerous willow thickets offering abundant host plants (mainly Salix sp. div.. Both the islands and the surroundings of the lake have a unique species composition, and there are differences in the proportions of the individual dominant species. The overall abundance of bees varies greatly, with mean seasonal density figures on Ostrów Lednicki Island being more than twice as high as that on the mainland grassland, with a distinct predominance of bumblebees. The exceptional richness of Apiformes, including bumblebees, on Ostrów Lednicki should be regarded as the basis for treating this island as a life refuge for bumblebees and including it and its environs in the list of sites of Community importance (SCI. A simultaneous study of the vegetation cover contributed significant data on the vascular plant flora and plant communities of the Lednica Landscape Park. For example, it was the first such investigation of Mewia Island. The study revealed the importance of marginal habitats (natural islands and habitat islands for the preservation of protected and endangered plant species and plant communities receding from an agricultural landscape.

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

    Science.gov (United States)

    Kalkan, Y.; Bilgi, S.

    2014-12-01

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

  5. Small dams need better management

    Science.gov (United States)

    Balcerak, Ernie

    2012-03-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  7. 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.

  8. Phytotoxicity of Sodium Fluoride and Uptake of Fluoride in Willow Trees

    DEFF Research Database (Denmark)

    Clausen, Lauge Peter Westergaard; Gosewinkel Karlson, Ulrich; Trapp, Stefan

    2015-01-01

    The willow tree (Salix viminalis) toxicity test and a cress seed germination test (Lepidium sativum) were used to determine uptake and phytotoxicity of NaF. Concentrations in hydroponic solutions were 0-1000 mg F/L and 0-400 mg F/L in the preliminary and definitive test. A third test was done...

  9. Conversion from cropland to short rotation coppice willow and poplar: Accumulation of soil organic carbon

    Science.gov (United States)

    Georgiadis, Petros; Stupak, Inge; Vesterdal, Lars; Raulund-Rasmussen, Karsten

    2015-04-01

    Increased demand for bioenergy has intensified the production of Short Rotation Coppice (SRC) willow and poplar in temperate zones. We used a combined chronosequence and paired plot approach to study the potential of SRC willow and poplar stands to increase the soil carbon stock compared to stocks of the previous arable land-use. The study focused on well-drained soils. We sampled soil from 30 SRC stands in Denmark and southern Sweden including soils from their adjacent arable fields. The 18 willow and 12 poplar stands formed a chronosequence ranging between 4 and 29 years after conversion. The soil was sampled both with soil cores taken by fixed depths of 0-5, 5-10, 10-15, 15-25, and 25-40 cm and by genetic horizons from soil pits to 1m depth. The aim of the study was to estimate the difference and the ratio between soil carbon contents of the SRC and annual crop land and analyze the results as a chronosequence to examine the effect of age after conversion on the difference. Covariates such as soil type, fertilization type and harvest frequency were also taken into account. Preliminary results suggest an overall increase in carbon stocks over time with average accumulation rates ranging from 0.25 to 0.4 Mg ha-1 yr-1 in willow and poplar stands. Poplar stands had higher rates of C gain, probably due to less frequent harvesting. The differences in carbon between the SRC and the paired cropland were initially negative but changed to positive over time, implying loss of carbon after conversion and a later gain in soil carbon with stand age. Pairwise differences ranged from -25 Mg C ha-1 to 37 Mg C ha-1 for the top 40 cm. The carbon stock ratio of the SRC stand to the arable land was estimated to minimize the effect of site-related factors. The results of this analysis suggested that the ratio increased significantly with age after conversion for the top 10 cm of the soil, both for poplar and willow. A slight increase with age was also noticed at the deeper depths, but

  10. Investigation of geophysical methods for assessing seepage and internal erosion in embankment dams : a study of through-dam seismic testing at WAC Bennett Dam

    Energy Technology Data Exchange (ETDEWEB)

    Gaffran, P.; Jeffries, M. [BC Hydro, Burnaby, BC (Canada)

    2005-07-15

    Crosshole tomography is used to establish the distribution of seismic velocity between drill holes. The through-dam mode takes advantage of the triangular cross-section of earth embankments, obviating the need for drill holes. Seismic energy, generated on one face of the dam, passes underneath the crest and is detected by sensors arrayed on the opposite face. The sinkholes discovered at WAC Bennett Dam in 1996 provided an opportunity to test the procedure. Using p-wave energy, two series of measurements were conducted, notably one immediately before remediation of one sinkhole, and a second one shortly after the sinkhole was repaired. The known defect was successfully imaged by the first round of measurements. This report presented the results of an investigation of the through-dam seismic method using propagation of seismic waves through a dam from upstream to downstream, or vice-versa. The purpose of the study was to determine if this procedure could characterize the distribution of seismic velocity within a dam in an accurate and cost effective manner. The report presented the methods of velocity testing such as crosshole and downhole, and tomography; and through-dam measurements. Background to the Bennett Dam studies was also provided, with particular reference to the Bennett Dam sinkholes; sinkhole investigations; working hypothesis for sinkhole development; sinkhole number one characterization; and sinkhole remediation. An analysis of compression wave testing at Bennett Dam and shear wave testing was then offered. Other topics that were discussed included field test procedures; methodologies for data processing; p-waves versus s-waves; applicability of the research; and costs of through-dam surveys. It was concluded that under the right circumstances, through-dam seismic testing was capable of detecting changed conditions in an embankment dam. 15 refs., 2 tabs., 41 figs., 1 appendix.

  11. Translocation of Cd and Mn from Bark to Leaves in Willows on Contaminated Sediments: Delayed Budburst Is Related to High Mn Concentrations

    Directory of Open Access Journals (Sweden)

    Bart Vandecasteele

    2015-04-01

    Full Text Available Changes in the hydrology of sediments in tidal marshes or landfills may affect the uptake of metals in the vegetation. Leaf and stem samples of Salix cinerea (grey sallow were collected during four consecutive growing seasons at six contaminated plots on a polluted dredged sediment landfill and one plot on an uncontaminated reference site. The first three contaminated plots were already emerged in the first half of the first growing season, while the other three were submerged in the first year, but became increasingly dry over the study period. Foliar and stem cutting concentrations for Cd, Zn and Mn increased on the latter three plots over the four years. Willow bark contained high concentrations of Cd, Zn and Mn. In two consecutive greenhouse experiments with willow cuttings from different origins (uncontaminated and contaminated sites and grown under different soil conditions (uncontaminated and contaminated, we observed an important translocation of Mn from bark to shoots. In a third experiment with willow cuttings collected on soils with a range of heavy metal concentrations and, thus, with a broad range of Cd (4–67 mg/kg dry matter, Zn (247–660 mg/kg dry matter and Mn (38–524 mg/kg dry matter concentrations in the bark, high Mn concentrations in the bark were found to affect the budburst of willow cuttings, while no association of delayed budburst with Cd and Zn concentrations in the bark was found. We conclude that wood and, especially, bark are not a sink for metals in living willows. The high Mn concentrations in the bark directly or indirectly caused delayed or restricted budburst of the willow cuttings.

  12. The level of invasion of the willow-poplar floodplain forests of Danube lowland

    International Nuclear Information System (INIS)

    Botkova, K.; Petrasova, K.

    2015-01-01

    Invasions of neophyte plant species are considered as one of the major threats to the diversity of natural ecosystems including floodplain forests. The aims of our study were to find out if there is a significant increase in the number and cover of neophyte species in the willow-poplar floodplain forests of Danube lowland over time. The level of invasion of the willow-poplar floodplain forests was evaluated from 1950 to the present time using Kruskal-Wallis non-parametric ANOVA. According to the analysis results, along the time gradient there is a significant increase in the number and cover of neophytes among analysed periods. This result is not caused by increasing biodiversity, because the number of native species significantly decreased. Therefor it is necessary to look for reasons of this situation in deteriorating condition of floodplain biotopes. (authors)

  13. Perspectives on dam safety in Canada

    International Nuclear Information System (INIS)

    Halliday, R.

    2004-01-01

    Canadian dam safety issues were reviewed from the perspective of a water resources engineer who is not a dam safety practitioner. Several external factors affecting dam safety were identified along with perceived problems in dam safety administration. The author claims that the main weakness in safety practices can be attributed to provincial oversights and lack of federal engagement. Some additions to the Canadian Dam Safety Guidelines were proposed to address these weaknesses. Canada has hundreds of large dams and high hazard dams whose failure would result in severe downstream consequences. The safety of dams built on boundary waters shared with the United States have gained particular attention from the International Joint Commission. This paper also examined safety criteria for concerns such as aging dams, sabotage and global climate change that may compromise the safety of a dam. 26 refs

  14. Potential effects of four Flaming Gorge Dam hydropower operational scenarios on riparian vegetation of the Green River, Utah and Colorado

    International Nuclear Information System (INIS)

    LaGory, K.E.; Van Lonkhuyzen, R.A.

    1995-06-01

    Four hydropower operational scenarios at Flaming Gorge Dam were evaluated to determine their potential effects on riparian vegetation along the Green River in Utah and Colorado. Data collected in June 1992 indicated that elevation above the river had the largest influence on plant distribution. A lower riparian zone occupied the area between the approximate elevations of 800 and 4,200-cfs flows--the area within the range of hydropower operational releases. The lower zone was dominated by wetland plants such as cattail, common spikerush, coyote willow, juncus, and carex. An upper riparian zone was above the elevation of historical maximum power plant releases from the dam (4,200 cfs), and it generally supported plants adapted to mesic, nonwetland conditions. Common species in the upper zone included box elder, rabbitbrush, grasses, golden aster, and scouring rush. Multispectral aerial videography of the Green River was collected in May and June 1992 to determine the relationship between flow and the areas of water and the riparian zone. From these relationships, it was estimated that the upper zone would decrease in extent by about 5% with year-round high fluctuation, seasonally adjusted high fluctuation, and seasonally adjusted moderate fluctuation, but it would increase by about 8% under seasonally adjusted steady flow. The lower zone would increase by about 13% for both year-round and seasonally adjusted high fluctuation scenarios but would decrease by about 40% and 74% for seasonally adjusted moderate fluctuation and steady flows, respectively. These changes are considered to be relatively minor and would leave pre-dam riparian vegetation unaffected. Occasional high releases above power plant capacity would be needed for long-term maintenance of this relict vegetation

  15. Clonal variation in survival and growth of hybrid poplar and willow in an in situ trial on soils heavily contaminated with petroleum hydrocarbons

    Science.gov (United States)

    Ronald S., Jr. Zalesny; Edmund O. Bauer; Richard B. Hall; Jill A. Zalesny; Joshua Kunzman; Chris J. Rog; Don E. Riemenschneider

    2005-01-01

    Species and hybrids between species belonging to the genera Populus (poplar) and Salix (willow) have been used successfully for phytoremediation of contaminated soils. Our objectives were to: 1) evaluate the potential for establishing genotypes of poplar and willow on soils heavily contaminated with petroleum hydrocarbons and 2)...

  16. 78 FR 53494 - Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams

    Science.gov (United States)

    2013-08-29

    ... Bar Dams AGENCY: Tennessee Valley Authority. ACTION: Issuance of Record of Decision. SUMMARY: This... the dam safety modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams. The notice of... Loudoun, Tellico, and Watts Bar Dams was published in the Federal Register on May 31, 2013. This...

  17. Climate impact and energy efficiency from electricity generation through anaerobic digestion or direct combustion of short rotation coppice willow

    International Nuclear Information System (INIS)

    Ericsson, Niclas; Nordberg, Åke; Sundberg, Cecilia; Ahlgren, Serina; Hansson, Per-Anders

    2014-01-01

    Highlights: • Using LCA, CHP from willow use in biogas was compared with direct combustion. • Direct combustion was ninefold more energy-efficient. • Biogas had a much greater cooling effect on global mean surface temperature. • The effects of soil carbon changes on temperature over time differed. • Biogas had long-term temperature effects, direct combustion short-term effects. - Abstract: Short rotation coppice willow is an energy crop used in Sweden to produce electricity and heat in combined heat and power plants. Recent laboratory-scale experiments have shown that SRC willow can also be used for biogas production in anaerobic digestion processes. Here, life cycle assessment is used to compare the climate impact and energy efficiency of electricity and heat generated by these measures. All energy inputs and greenhouse gas emissions, including soil organic carbon fluxes were included in the life cycle assessment. The climate impact was determined using time-dependent life cycle assessment methodology. Both systems showed a positive net energy balance, but the direct combustion system delivered ninefold more energy than the biogas system. Both systems had a cooling effect on the global mean surface temperature change. The cooling impact per hectare from the biogas system was ninefold higher due to the carbon returned to soil with the digestate. Compensating the lower energy production of the biogas system with external energy sources had a large impact on the result, effectively determining whether the biogas scenario had a net warming or cooling contribution to the global mean temperature change per kWh of electricity. In all cases, the contribution to global warming was lowered by the inclusion of willow in the energy system. The use of time-dependent climate impact methodology shows that extended use of short rotation coppice willow can contribute to counteract global warming

  18. Extracellular enzyme activity in a willow sewage treatment system.

    Science.gov (United States)

    Brzezinska, Maria Swiontek; Lalke-Porczyk, Elżbieta; Kalwasińska, Agnieszka

    2012-12-01

    This paper presents the results of studies on the activity of extra-cellular enzymes in soil-willow vegetation filter soil which is used in the post-treatment of household sewage in an onsite wastewater treatment system located in central Poland. Wastewater is discharged from the detached house by gravity into the onsite wastewater treatment system. It flows through a connecting pipe into a single-chamber septic tank and is directed by the connecting pipe to a control well to be further channelled in the soil-willow filter by means of a subsurface leaching system. Soil samples for the studies were collected from two depths of 5 cm and 1 m from three plots: close to the wastewater inflow, at mid-length of the plot and close to its terminal part. Soil samples were collected from May to October 2009. The activity of the extra-cellular enzymes was assayed by the fluorometric method using 4-methylumbelliferyl and 7-amido-4-methylcoumarin substrate. The ranking of potential activity of the assayed enzymes was the same at 5 cm and 1 m soil depths, i.e. esterase > phosphmomoesterase > leucine-aminopeptidase > β-glucosidase > α-glucosidase. The highest values of enzymatic activity were recorded in the surface layer of the soil at the wastewater inflow and decreased with increasing distance from that point.

  19. Late Quaternary vegetation and climate history of the central Bering land bridge from St. Michael Island, western Alaska

    Science.gov (United States)

    Ager, T.A.

    2003-01-01

    Pollen analysis of a sediment core from Zagoskin Lake on St. Michael Island, northeast Bering Sea, provides a history of vegetation and climate for the central Bering land bridge and adjacent western Alaska for the past ???30,000 14C yr B.P. During the late middle Wisconsin interstadial (???30,000-26,000 14C yr B.P.) vegetation was dominated by graminoid-herb tundra with willows (Salix) and minor dwarf birch (Betula nana) and Ericales. During the late Wisconsin glacial interval (26,000-15,000 14C yr B.P.) vegetation was graminoid-herb tundra with willows, but with fewer dwarf birch and Ericales, and more herb types associated with dry habitats and disturbed soils. Grasses (Poaceae) dominated during the peak of this glacial interval. Graminoid-herb tundra suggests that central Beringia had a cold, arid climate from ???30,000 to 15,000 14C yr B.P. Between 15,000 and 13,000 14C yr B.P., birch shrub-Ericales-sedge-moss tundra began to spread rapidly across the land bridge and Alaska. This major vegetation change suggests moister, warmer summer climates and deeper winter snows. A brief invasion of Populus (poplar, aspen) occurred ca. 11,000-9500 14C yr B.P., overlapping with the Younger Dryas interval of dry, cooler(?) climate. During the latest Wisconsin to middle Holocene the Bering land bridge was flooded by rising seas. Alder shrubs (Alnus crispa) colonized the St. Michael Island area ca. 8000 14C yr B.P. Boreal forests dominated by spruce (Picea) spread from interior Alaska into the eastern Norton Sound area in middle Holocene time, but have not spread as far west as St. Michael Island. ?? 2003 University of Washington. Published by Elsevier Inc. All rights reserved.

  20. Evaluating growth effects from an imidacloprid treatment in black willow and eastern cottonwood cuttings

    Science.gov (United States)

    Luciano de Sene Fernandes; Ray A. Souter; Theodor D. Leininger

    2015-01-01

    Black willow (Salix nigra Marsh.) and eastern cottonwood (Populus deltoides Bartram ex Marsh.), two species native in the Lower Mississippi Alluvial Valley, have importance in short rotation woody crop (SRWC) systems for biomass production (Ruark 2006).

  1. Vegetative reproduction capacities of floodplain willows--cutting response to competition and biomass loss.

    Science.gov (United States)

    Radtke, A; Mosner, E; Leyer, I

    2012-03-01

    While several studies on regeneration in Salicaceae have focused on seedling recruitment, little is known about factors controlling their vegetative reproduction. In two greenhouse experiments, we studied the response of floodplain willows (Salix fragilis, S. viminalis, S. triandra) to competition with Poa trivialis, and to shoot and root removal when planted as vegetative cuttings. In the first experiment, growth performance variables were analysed in relation to full competition, shoot competition, root competition and control, taking into account two different water levels. After 9 weeks, shoots were removed and the resprouting capacity of the bare cuttings was recorded. In the second experiment, the cutting performance of the three floodplain and an additional two fen willow species (S. cinerea, S. aurita) was compared when grown in three different soil compositions and with two different water levels. After 9 weeks, shoot and root biomass was removed and the bare cuttings were replanted to test their ability to resprout. Cutting performance and secondary resprouting were negatively affected by full and shoot competition while root competition had no or weak effects. The floodplain species performed better than the fen species in all soil types and water levels. Secondary resprouting capacity was also higher in the floodplain species, which showed an additional strong positive response to the previous waterlogging treatment. The results contribute to understanding of the vegetative regeneration ecology of floodplain willows, and suggest that the use of vegetative plantings in restoration plantings could be an effective strategy for recovering floodplain forests. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. 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

    Full Text Available Introduction: Cracking of earth dams is a one of the main threat causes of stability of embankment dams. In this research by modeling of the behavior of an embankment dam and employing conditions of the earthquake, the reasons of cracking were inspected using by modeling of earth dam behavior. Based on the literature, one of the main causes of dam failures is sliding and cracking of the dam structure during earthquake. Localized liquefaction of foundation soils was one of the causes of the observed post-earthquake distress within these dams. Material and Methods: In order to study the causes and the results of crack on earth dams, Mahmoodabad earthen dam with a height of 19 m, is located in Zanjan province, northwest of Iran, which suffered a longitudinal crack on the crest and slight sliding of the upstream slope due to 2001 Avaj earthquake was studied. This dam has faced earthquake two times with an interval of two years. During the first earthquake with the magnitude about 6.6 in Richter scale small longitudinal cracks had created on the crest. The developed cracks had been repaired by injecting the cement and then has been hidden by passing the time. After the second earthquake with the magnitude about 6.5 in Richter scale the hidden cracks had been appeared again and the slight movement of the upper slopes of dam reported. Based on the site investigation and documented information about dam, including maps and parameter data, the behavior of the dam has modeled by using Plaxis as a finite element model. In order to check the accuracy of the design of dam, the stability analysis has been conducted using by Xslope as a limit equilibrium model. The foundation conditions and the Geotechnical properties of the layer beneath the dam has been inspected by open excavation. Results and Discussion: Underground investigation about Geotechnical properties of dam foundation has showed that there is a thin sandy layer confined in alluvium material of the

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

    Science.gov (United States)

    Peng, M.; Zhang, L. M.

    2013-02-01

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

  4. Water relations and gas exchange in poplar and willow under water stress and elevated atmospheric CO2.

    Science.gov (United States)

    Johnson, Jon D; Tognetti, Roberto; Paris, Piero

    2002-05-01

    Predictions of shifts in rainfall patterns as atmospheric [CO2] increases could impact the growth of fast growing trees such as Populus spp. and Salix spp. and the interaction between elevated CO2 and water stress in these species is unknown. The objectives of this study were to characterize the responses to elevated CO2 and water stress in these two species, and to determine if elevated CO2 mitigated drought stress effects. Gas exchange, water potential components, whole plant transpiration and growth response to soil drying and recovery were assessed in hybrid poplar (clone 53-246) and willow (Salix sagitta) rooted cuttings growing in either ambient (350 &mgr;mol mol-1) or elevated (700 &mgr;mol mol-1) atmospheric CO2 concentration ([CO2]). Predawn water potential decreased with increasing water stress while midday water potentials remained unchanged (isohydric response). Turgor potentials at both predawn and midday increased in elevated [CO2], indicative of osmotic adjustment. Gas exchange was reduced by water stress while elevated [CO2] increased photosynthetic rates, reduced leaf conductance and nearly doubled instantaneous transpiration efficiency in both species. Dark respiration decreased in elevated [CO2] and water stress reduced Rd in the trees growing in ambient [CO2]. Willow had 56% lower whole plant hydraulic conductivity than poplar, and showed a 14% increase in elevated [CO2] while poplar was unresponsive. The physiological responses exhibited by poplar and willow to elevated [CO2] and water stress, singly, suggest that these species respond like other tree species. The interaction of [CO2] and water stress suggests that elevated [CO2] did mitigate the effects of water stress in willow, but not in poplar.

  5. COMPACTION STUDIES OF TORREFIED WILLOW

    Directory of Open Access Journals (Sweden)

    Michał Rejdak

    2017-01-01

    Full Text Available The article presents the results of studies of torrefied willow (Salix viminalis L. compaction. Densification tests were performed using a hydraulic press with a maximum pressure of 216 MPa. The effect of basic parameters of the briquetting process (pressure and temperature on mechanical parameters of manufactured briquettes were determined. On the basis of the research, it was found that the increase in pressure and temperature of the densification process increases the density and strength of pressed briquettes. The positive effect of temperature is particularly noticeable at lower pressing pressures (36 MPa – 72 MPa. In the case of a temperature of 300 °C, the increase in a pressure from 144 MPa to 216 MPa resulted in the decrease in the density and strength of the briquette. It was also found that the briquettes manufactured at this temperature are characterized by lower density and strength than the briquettes obtained at a temperature of 200 °C.

  6. Development of short-rotation willow coppice systems for environmental purposes in Sweden

    International Nuclear Information System (INIS)

    Mirck, Jaconette; Verwijst, Theo; Isebrands, J.G.; Ledin, Stig

    2005-01-01

    During the last three decades, driving forces behind the development of short-rotation willow coppice (SRWC) in Sweden have been changing from a primary focus on biomass production towards emphasis on environmental applications. In most cases, current commercial SRWC practice is geared towards a combination of biomass production for energy purposes and environmental goals. The latter goals range from decreasing the impact of specific contaminants in the environment to organic waste handling in a recycling system in urban and/or agricultural areas. Where biomass production and pollutant management overlap, the science of phytoremediation has its practical application. Through phytoremediation, waste products that previously have been a burden for society can be used as valuable resources to increase short-rotation willow biomass production. In this paper we will present the terminology and definitions of different types of phytoremediation. We also give an overview of five different cases of phytoremediation activities with a potential for large-scale implementation. Some of the types of activities are already commercially used in Sweden; others seem promising but still need further development. (Author)

  7. 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

  8. Southwestern willow flycatchers (Empidonax traillii extimus) in a grazed landscape: factors influencing brood parasitism

    Science.gov (United States)

    Katherine M. Brodhead; Scott H. Stoleson; Deborah M. Finch

    2007-01-01

    Brood parasitism by Brown-headed Cowbirds (Molothrus ater; hereafter "cowbirds") is an important factor contributing to the endangered status of the Southwestern Willow Flycatcher (Empidonax traillii extimus, hereafter "flycatcher"). We report on factors that influence brood parasitism on the flycatcher using...

  9. Dam safety operating guidelines

    International Nuclear Information System (INIS)

    Elsayed, E.; Leung, T.; Kirkham, A.; Lum, D.

    1990-01-01

    As part of Ontario Hydro's dam structure assessment program, the hydraulic design review of several river systems has revealed that many existing dam sites, under current operating procedures, would not have sufficient discharge capacity to pass the Inflow Design Flood (IDF) without compromising the integrity of the associated structures. Typical mitigative measures usually considered in dealing with these dam sites include structural alterations, emergency action plans and/or special operating procedures designed for extreme floods. A pilot study was carried out for the Madawaska River system in eastern Ontario, which has seven Ontario Hydro dam sites in series, to develop and evaluate the effectiveness of the Dam Safety Operating Guidelines (DSOG). The DSOG consist of two components: the flood routing schedules and the minimum discharge schedules, the former of which would apply in the case of severe spring flood conditions when the maximum observed snowpack water content and the forecast rainfall depth exceed threshold values. The flood routing schedules would identify to the operator the optimal timing and/or extent of utilizing the discharge facilities at each dam site to minimize the potential for dam failures cased by overtopping anywhere in the system. It was found that the DSOG reduced the number of structures overtopped during probable maximum flood from thirteen to four, while the number of structures that could fail would be reduced from seven to two. 8 refs., 4 figs., 3 tabs

  10. Dam risk reduction study for a number of large tailings dams in Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Verma, N. [AMEC Earth and Environmental Ltd., Mississauga, ON (Canada); Small, A. [AMEC Earth and Environmental Ltd., Fredericton, NB (Canada); Martin, T. [AMEC Earth and Environmental, Burnaby, BC (Canada); Cacciotti, D. [AMEC Earth and Environmental Ltd., Sudbury, ON (Canada); Ross, T. [Vale Inco Ltd., Sudbury, ON (Canada)

    2009-07-01

    This paper discussed a risk reduction study conducted for 10 large tailings dams located at a central tailings facility in Ontario. Located near large industrial and urban developments, the tailings dams were built using an upstream method of construction that did not involve beach compaction or the provision of under-drainage. The study provided a historical background for the dam and presented results from investigations and instrumentation data. The methods used to develop the dam configurations were discussed, and remedial measures and risk assessment measures used on the dams were reviewed. The aim of the study was to address key sources of risk, which include the presence of high pore pressures and hydraulic gradients; the potential for liquefaction; slope instability; and the potential for overtopping. A borehole investigation was conducted and piezocone probes were used to obtain continuous data and determine soil and groundwater conditions. The study identified that the lower portion of the dam slopes were of concern. Erosion gullies could lead to larger scale failures, and elevated pore pressures could lead to the risk of seepage breakouts. It was concluded that remedial measures are now being conducted to ensure slope stability. 6 refs., 1 tab., 6 figs.

  11. Fragmentation by Dams Threatens Diadromous Fauna in Upstream Protected Areas - the Case of the La Amistad World Heritage Site (Costa Rica and Panama)

    Science.gov (United States)

    McLarney, W.; Mafla Herrera, M.; Arias Moreno, A. M.; Snyder, M. N.

    2016-12-01

    Biological consequences of fragmenting rivers with dams are especially acute for migratory species, and even moreso for diadromes (animals obliged to travel between marine and fresh water environments in order to complete their life cycles). Diadromy is a worldwide phenomenon, occurring wherever fresh water rivers run to the sea. Worldwide, diadromous behavior has been described for > 300 species of fish in 37 families, as well as for all of the > 800 species of so-called "freshwater" shrimp in 4 families, plus a few crabs and snails. Diadromy is especially prevalent on islands and isthmuses, where rivers are necessarily short and development of primary freshwater fauna limited. One example is the Mesoamerican isthmus, extending from southern Mexico to the Panama/Colombia border. A 2006 study showed more than 300 high (> 15 m.) dams planned for this 8 country region. One example of the consequences emerges from Asociacion ANAI's biomonitoring work over 17 years in one part of Mesoamerica - the watersheds draining the Caribbean slope of the La Amistad World Heritage Site in Costa Rica and Panama. Our work has shown that over 80 % of fish and all of the shrimp in rivers above 100 m. altitude are diadromes. If all currently planned dams are built, we predict that 11 species of fish and shrimp will be extirpated from >90% of the World Heritage Site. Precedent exists in Puerto Rico, where damming has eliminated diadromous fish and all but a remnant of the shrimp from 25% of the island's watersheds. In La Amistad, the consequences, for biodiversity and fishery resources relied upon by neighboring indigenous ethnias are obvious. In Panama, protected area boundaries were drawn to avoid the issue of dams and reservoirs in national parks; our research shows the need for more comprehensive design criteria to prevent extirpations in protected areas.

  12. The Effects of Dams on Downstream Channel Characteristics in Pennsylvania and Maryland: Assessing the Potential Consequences of Dam Removal

    Science.gov (United States)

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

    2003-12-01

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

  13. Public safety around dams guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, T [Canadian Dam Association, Edmonton, AB (Canada)

    2010-07-01

    This presentation discussed Canadian and international initiatives for improving dam safety and described some of the drivers for the development of new Canadian Dam Association (CDA) public safety guidelines for dams. The CDA guidelines were divided into the following 3 principal sections: (1) managed system elements, (2) risk assessment and management, and (3) technical bulletins. Public and media responses to the drownings have called for improved safety guidelines. While the public remains unaware of the hazards of dams, public interaction with dams is increasing as a result of interest in extreme sports and perceived rights of access. Guidelines are needed for dam owners in order to provide due diligence. Various organizations in Canada are preparing technical and public safety dam guidelines. CDA guidelines have also been prepared for signage, booms and buoys, and audible and visual alerts bulletins. Working groups are also discussing recommended practices for spill procedures, spillways and the role of professional engineers in ensuring public safety. Methods of assessing risk were also reviewed. Managed system elements for risk assessment and public interactions were also discussed, and stepped control measures were presented. tabs., figs.

  14. Odelouca Dam Construction: Numerical Analysis

    OpenAIRE

    Brito, A.; Maranha, J. R.; Caldeira, L.

    2012-01-01

    Odelouca dam is an embankment dam, with 76 m height, recently constructed in the south of Portugal. It is zoned with a core consisting of colluvial and residual schist soil and with soil-rockfill mixtures making up the shells (weathered schist with a significant fraction of coarse sized particles). This paper presents a numerical analysis of Odelouca Dam`s construction. The material con-stants of the soil model used are determined from a comprehensive testing programme carried out in the C...

  15. Effect of a dam on epilithic algal communities of a mountain stream: before-after dam construction comparison

    Directory of Open Access Journals (Sweden)

    Luciana Cibils Martina

    2013-02-01

    Full Text Available In this study we evaluated the effect of a dam on epilithic algal communities by analyzing community response after dam construction and by comparing community composition, structure and biomass upstream and downstream of the dam. Samples of epilithic algae and environmental data were collected at each site during high and low water periods before and after dam construction in Achiras Stream (Córdoba, Argentina. Ordinations showed modifications in algal assemblages after dam construction and downstream of the dam. Ordinations also suggested a loss of seasonality at the downstream site since the assemblages were similar between hydrological periods after dam construction. Indicator species, obtained by the Indicator Value method, showed that, after dam construction, there could have been an increase in nutrient concentration and a release of plankton from the impoundment. Abundance, richness and diversity were altered after dam construction as assessed by ANOVAs derived from a modified BACI Design. Proportion of early-successional species was higher at the upstream site while late-successional species were dominant at the downstream site, as predicted. Lower fluctuations in discharge downstream of the dam may have helped succession advance, whereas at the upstream site, mainly during the high water period, floods could have caused sloughing of life forms from the outer layers of the biofilm, resetting the algal community to early successional stages. It may be concluded that the dam affected algal community and favored succession advance mainly by reducing current velocity and flow fluctuations.

  16. Effect of temperature on the uptake and metabolism of cyanide by weeping willows

    DEFF Research Database (Denmark)

    Yu, X.-Z.; Trapp, Stefan; Zhou, P.-H.

    2007-01-01

    Plants’ uptake and metabolism of cyanide in response to changes in temperature was investigated. Pre-rooted weeping willows (Salix babylonica L.) were exposed to hydroponic solution spiked with potassium cyanide for 2–3 d. Ten different temperatures were used, ranging from 11◦C to 32◦C. Cyanide...

  17. 78 FR 77397 - Flood Control Regulations, Marshall Ford Dam (Mansfield Dam and Lake Travis), Colorado River, Texas

    Science.gov (United States)

    2013-12-23

    ... Regulations, Marshall Ford Dam (Mansfield Dam and Lake Travis), Colorado River, Texas AGENCY: U.S. Army Corps... Marshall Ford Dam (Mansfield Dam and Lake Travis), Colorado River, Texas. In 1997, the Lower Colorado River... regulations to reflect changes in ownership and responsibilities of flood control management of Marshall Ford...

  18. 7 CFR 1724.55 - Dam safety.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Dam safety. 1724.55 Section 1724.55 Agriculture... § 1724.55 Dam safety. (a) The provisions of this section apply only to RUS financed electric system... for Dam Safety,”(Guidelines), as applicable. A dam, as more fully defined in the Guidelines, is...

  19. New guidelines for dam safety classification

    International Nuclear Information System (INIS)

    Dascal, O.

    1999-01-01

    Elements are outlined of recommended new guidelines for safety classification of dams. Arguments are provided for the view that dam classification systems should require more than one system as follows: (a) classification for selection of design criteria, operation procedures and emergency measures plans, based on potential consequences of a dam failure - the hazard classification of water retaining structures; (b) classification for establishment of surveillance activities and for safety evaluation of dams, based on the probability and consequences of failure - the risk classification of water retaining structures; and (c) classification for establishment of water management plans, for safety evaluation of the entire project, for preparation of emergency measures plans, for definition of the frequency and extent of maintenance operations, and for evaluation of changes and modifications required - the hazard classification of the project. The hazard classification of the dam considers, as consequence, mainly the loss of lives or persons in jeopardy and the property damages to third parties. Difficulties in determining the risk classification of the dam lie in the fact that no tool exists to evaluate the probability of the dam's failure. To overcome this, the probability of failure can be substituted for by a set of dam characteristics that express the failure potential of the dam and its foundation. The hazard classification of the entire project is based on the probable consequences of dam failure influencing: loss of life, persons in jeopardy, property and environmental damage. The classification scheme is illustrated for dam threatening events such as earthquakes and floods. 17 refs., 5 tabs

  20. War damages and reconstruction of Peruca dam

    International Nuclear Information System (INIS)

    Nonveiller, E.; Sever, Z.

    1999-01-01

    The paper describes the heavy damages caused by blasting in the Peruca rockfill dam in Croatia in January 1993. Complete collapse of the dam by overtopping was prevented through quick action of the dam owner by dumping clayey gravel on the lowest sections of the dam crest and opening the bottom outlet of the reservoir, thus efficiently lowering the water level. After the damages were sufficiently established and alternatives for restoration of the dam were evaluated, it was decided to construct a diaphragm wall through the damaged core in the central dam part as the impermeable dam element and to rebuild the central clay core at the dam abutments. Reconstruction works are described

  1. 33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.

    Science.gov (United States)

    2010-07-01

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

  2. Excavation of the Surikamigawa dam diversion tunnel. Surikamigawa dam karihaisui tunnel kantsu

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, T.; Konno, T. (Ministry of Construction, Tokyo (Japan))

    1994-04-01

    A bypass tunnel construction has been completed at the Surikamigawa dam (Japan). This paper describes the summary of the construction. The full-swing dam construction work is scheduled to begin in 1995. The soils distributed near the dam site consist of lapillus tuff containing andesite-based light stones and tuff-based conglomerates containing large gravels. Excavation of the dam diversion tunnel has used a blasting method, and the tunnel construction has adopted an automatic tunnel cross section marking system and a non-electric explosion method. This marking system is a system to irradiate a laser beam onto the facing to depict excavation lines that realizes labor saving and high-accuracy excavation. The error at the tunnel completion was found 20 mm. The non-electric explosion method ignites a coated explosive layer with an impact wave, which is electrostatically safe, and reduces blasting vibration. Electric detonators have also been used because of using ANFO explosives. The result obtained from measurements of inner space displacement necessary for the blasting process has indicated that the area near the dam site consists of stable mountains. 6 figs., 4 tabs.

  3. Three Sisters Dam modifications and performance

    Energy Technology Data Exchange (ETDEWEB)

    Courage, L.J.R. [Monenco AGRA Inc., Calgary, AB (Canada)

    1995-12-31

    Recent modifications and maintenance carried out at the Three Sisters Dam, in the Alberta Rockies south of the town of Canmore, were described. A detailed account was given of the dam`s geological setting, its abnormally high leakage through the foundation and its sinkhole activity. Results of studies aimed at finding the cause of leakage and sinkhole occurrences were reviewed. Modifications made to the dam since 1951 were detailed, as were modifications to handle probable maximum flood levels. Three approaches for estimating failure probabilities after identification of failure modes were described. The overall conclusion was that based on constant leakage, no settlement in the dam, penstocks, or the powerhouse since construction, the Three Sisters Dam was stable. 1 ref.

  4. Dams and Levees: Safety Risks

    Science.gov (United States)

    Carter, N. T.

    2017-12-01

    The nation's flood risk is increasing. The condition of U.S. dams and levees contributes to that risk. Dams and levee owners are responsible for the safety, maintenance, and rehabilitation of their facilities. Dams-Of the more than 90,000 dams in the United States, about 4% are federally owned and operated; 96% are owned by state and local governments, public utilities, or private companies. States regulate dams that are not federally owned. The number of high-hazard dams (i.e., dams whose failure would likely result in the loss of human life) has increased in the past decade. Roughly 1,780 state-regulated, high-hazard facilities with structural ratings of poor or unsatisfactory need rehabilitation. Levees-There are approximately 100,000 miles of levees in the nation; most levees are owned and maintained by municipalities and agricultural districts. Few states have levee safety programs. The U.S. Army Corps of Engineers (Corps) inspects 15,000 miles of levees, including levees that it owns and local levees participating in a federal program to assist with certain post-flood repairs. Information is limited on how regularly other levees are inspected. The consequence of a breach or failure is another aspect of risk. State and local governments have significant authority over land use and development, which can shape the social and economic impacts of a breach or failure; they also lead on emergency planning and related outreach. To date, federal dam and levee safety efforts have consisted primarily of (1) support for state dam safety standards and programs, (2) investments at federally owned dams and levees, and (3) since 2007, creation of a national levee database and enhanced efforts and procedures for Corps levee inspections and assessments. In Public Law 113-121, enacted in 2014, Congress (1) directed the Corps to develop voluntary guidelines for levee safety and an associated hazard potential classification system for levees, and (2) authorized support for the

  5. Phytotoxicity of fresh and weathered diesel and gasoline to willow and poplar trees

    DEFF Research Database (Denmark)

    Trapp, Stefan; Köhler, A.; Larsen, L.C.

    2001-01-01

    The toxicity of fresh and weathered gasoline and diesel fuel to willow and poplar trees was studied using a tree transpiration toxicity test. Soils were taken from an abandoned filling station. Concentrations in the samples were measured as the sum of hydrocarbons from C5 to C10 (gasoline) and C1...

  6. Health impacts of large dams

    International Nuclear Information System (INIS)

    Lerer, L.B.

    1999-01-01

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

  7. Seasonal variation in radiocaesium concentration in willow ptarmigan and rock ptarmigan in central Norway after the Chernobyl fallout

    International Nuclear Information System (INIS)

    Pedersen, H.C.; Nyboe, S.; Varskog, P.

    1998-01-01

    Radioactive caesium (20-60 kBq m -2 ) was deposited after the Chernobyl accident in the mountains of central Norway. Two sympatric ptarmigan species, willow ptarmigan Lagopus lagopus and rock ptarmigan L. mutus, inhabit this alpine ecosystem and are important game species. In 1987 and 1988, a study was carried out to try to identify factors affecting radioactive caesium concentration in these birds. Juvenile willow ptarmigan contained more radiocaesium than adults, but the two sexes did not differ in radiocaesium concentration. The radiocaesium concentration of food plants correlated with radiocaesium concentration of rock ptarmigan, and a seasonal variation in radiocaesium concentration of both ptarmigan species was seen. Rock ptarmigan contained more radiocaesium than willow ptarmigan during winter, but not in summer. This difference was related to differences in diet. The bioconcentration factor was 0·4-0·6. The aggregated transfer coefficient was 0·003-0·009 m 2 kg -1 for both species. In spite of the high deposition, the radiocaesium concentration in muscle rarely exceeded the limit recommended for human food consumption (600 Bq kg -1 ). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  8. Deformation performance of Waba Dam

    Energy Technology Data Exchange (ETDEWEB)

    Salloum, T.; Bhardwaj, V.; Hassan, P. [Ontario Power Generation, Niagara-on-the-Lake, ON (Canada); Cragg, C. [Cragg Consulting Services, Toronto, ON (Canada)

    2009-07-01

    This paper described the performance of the Waba Dam which is being monitored as part of Ontario Power Generation's Dam Safety Program. It described the deformations that have been observed in this 3600 ft long earthfill dam which lies on marine clay in eastern Ontario. An extensive instrumentation program, including foundation settlement gauges, surface monuments, slope inclinometers, load cells and piezometers has been in effect since the construction of the dam in 1975. Significant settlement has occurred at Waba Dam since its construction. Wide berms were provided upstream and downstream beyond the slopes of the main fill to ensure stability of the dyke on the soft clay foundation and the crest elevations were designed to allow for the expected settlement in the foundation which would be overstressed by the dam loading. Based on current settlements, future settlements are predicted based on Asaoka's method. Inclinometer measurements have shown a foundation lateral spreading of 12 in. The lateral versus vertical deformations were found to be comparable to well behaving embankments reported in the literature. These analyses indicate that Waba Dam is performing well and should continue to perform well into the future. 8 refs., 1 tab., 14 figs.

  9. 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.

  10. Positive impact of bio-stimulators on growth and physiological activity of willow in climate change conditions

    Science.gov (United States)

    Piotrowski, Krzysztof; Romanowska-Duda, Zdzisława

    2018-04-01

    The aim of this research was to evaluate the physiological activity and growth of willow (Salix viminalis L.) plants cultivated under the conditions of adverse temperature and soil moisture content, and to assess the effect of the foliar application of Biojodis (1.0%) and Asahi SL (0.03%) bio-stimulators, or a mixture of Microcistis aeruginosa MKR 0105 and Anabaena PCC 7120 cyanobacteria under such changing growth conditions. The obtained results showed different reactions to the applied constant or periodically changed temperature and soil moisture content. The plants which grew at periodically changed adverse temperature (from -5 to 40oC) or in scantily (20% m.c.) or excessively (60% m.c.) watered soils, grew slowly, in comparison with those growing at 20oC and in optimally moistened soil (30% m.c.). Foliar application of Biojodis and Asahi SL cyanobacteria increased the growth of willow at optimal and adverse temperature or in scantily and excessively moistened soil. The changes in plant growth were associated with the changes in electrolyte leakage, activity of acid or alkaline phosphatases, RNase, index of chlorophyll content in leaves and gas exchange. The above indicates that the foliar application of the studied cyanobacteria and bio-stimulators partly alleviates the harmful impact of adverse temperature and water stress on growth and physiological activity of willow plants

  11. Phytoremediation capacity of poplar (Populus spp. and willow (Salix spp. clonesin relation to photosynthesis

    Directory of Open Access Journals (Sweden)

    Pajević Slobodanka

    2009-01-01

    Full Text Available Good photosynthetic features and a favorable water regimes of woody plants improve their survival and remediation potential under unfavorable ecological conditions. Accordingly, we here present results of testing plant tolerance of Pb, Cd, Ni, and diesel fuel based on gas exchange parameters and WUE of four poplar and two willow clones grown in a greenhouse on soil culture. Photosynthesis and transpiration of plants grown on soils with individually applied heavy metals decreased significantly, but this was less obvious in the case of Cd treatment. A heavy metal mixture in the soil induced significant reduction in photosynthesis (by more than 50%. Diesel fuel as the only pollutant in soil caused very strong and significant inhibition of photosynthesis and transpiration of willow clones. The results indicate genotypic specificity of all investigated physiological parameters and mark poplar clones as very useful in phytoextraction technology for the bio-cleaning of chemically polluted soils.

  12. Total Dissolved Gas Monitoring in Chum Salmon Spawning Gravels Below Bonneville Dam

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Geist, David R.; Panther, Jennifer L.; Dawley, Earl

    2007-01-30

    At the request of the U.S. Army Corps of Engineers (Portland District), Pacific Northwest National Laboratory (PNNL) conducted research to determine whether total dissolved gas concentrations are elevated in chum salmon redds during spring spill operations at Bonneville Dam. The study involved monitoring the total dissolved gas levels at egg pocket depth and in the river at two chum salmon spawning locations downstream from Bonneville Dam. Dissolved atmospheric gas supersaturation generated by spill from Bonneville Dam may diminish survival of chum (Oncorhynchus keta) salmon when sac fry are still present in the gravel downstream from Bonneville Dam. However, no previous work has been conducted to determine whether total dissolved gas (TDG) levels are elevated during spring spill operations within incubation habitats. The guidance used by hydropower system managers to provide protection for pre-emergent chum salmon fry has been to limit TDG to 105% after allowing for depth compensation. A previous literature review completed in early 2006 shows that TDG levels as low as 103% have been documented to cause mortality in sac fry. Our study measured TDG in the incubation environment to evaluate whether these levels were exceeded during spring spill operations. Total dissolved gas levels were measured within chum salmon spawning areas near Ives Island and Multnomah Falls on the Columbia River. Water quality sensors screened at egg pocket depth and to the river were installed at both sites. At each location, we also measured dissolved oxygen, temperature, specific conductance, and water depth to assist with the interpretation of TDG results. Total dissolved gas was depth-compensated to determine when levels were high enough to potentially affect sac fry. This report provides detailed descriptions of the two study sites downstream of Bonneville Dam, as well as the equipment and procedures employed to monitor the TDG levels at the study sites. Results of the monitoring at

  13. Fragility Analysis of Concrete Gravity Dams

    Science.gov (United States)

    Tekie, Paulos B.; Ellingwood, Bruce R.

    2002-09-01

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

  14. The role of dams in development

    International Nuclear Information System (INIS)

    Cakmak, C.

    2001-01-01

    Although the amounts of water resources are enough for the entire world, the distribution of them in time and space shows uneven pattern. The water need is increasing with heavy industrial and agricultural requirements, while available water in the world remains as a fixed source. Economic growth, socio-cultural, and environmental developments are being realized following these changes. In order to achieve sustainable management of water resources, these changes have to be taken into consideration in water-related development projects. Demand for water is steadily increasing through out the world, even though the fresh water resources are limited and unevenly distributed, during the past three centuries, the amount of water withdrawn from fresh water resources has increased by a factor of 35, whereas world population by a factor 8. The engineering of dams, which provides regular water from reservoirs of dams to be used in case of demand pattern, is a vital part of the civilization. Dams have played a key rote in the development since the third millennium B C when the first great civilizations evolved on major rivers, such as Tigris-Euphrates, the Nile and the Indus. From these early times dams were built for flood control, water supply, irrigation and navigation. Dams also had been built to produce motive power and electricity since the industrial revolution. Development priorities changed, experience accumulated with the construction and operation of dams. Although the importance of water is well known in the human life and civilization around the world, still various groups argue that expected economic benefits are not being produced and that major environmental, economic and social costs are not being taken into account. By the end of 20th century, there were 45000 large dams in over 150 countries. According to the same classification there are 625 large dams in Turkey. All over the world, 50 % of the large dams were built mainly for irrigation. It is estimated

  15. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville Dam; 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Duff, Cameron; Brooks, Robert (Oregon Department of Fish and Wildlife, Columbia River Section, John Day, OR)

    2005-01-01

    In 2003 a total of 253 adult fall chinook and 113 chum were sampled for biological data in the Ives and Pierce islands area below Bonneville Dam. Vital statistics were developed from 221 fall chinook and 109 chum samples. The peak redd count for fall chinook was 190. The peak redd count for chum was 262. Peak spawning time for fall chinook was set at approximately 24 November. Peak spawning time for chum occurred approximately 24 November. There were estimated to be a total of 1,533 fall chinook spawning below Bonneville Dam in 2003. The study area's 2003 chum population was estimated to be 688 spawning fish. Temperature unit data suggests that below Bonneville Dam 2003 brood bright stock, fall chinook emergence began on January 6, 2004 and ended 28 April 2004, with peak emergence occurring 13 April. 2003 brood juvenile chum emergence below Bonneville Dam began 22 February and continued through 15 April 2004. Peak chum emergence took place 25 March. A total of 25,433 juvenile chinook and 4,864 juvenile chum were sampled between the dates of 20 January and 28 June 2004 below Bonneville Dam. Juvenile chum migrated from the study area in the 40-55 mm fork length range. Migration of chum occurred during the months of March, April and May. Sampling results suggest fall chinook migration from rearing areas took place during the month of June 2004 when juvenile fall chinook were in the 65 to 80 mm fork length size range. Adult and juvenile sampling below Bonneville Dam provided information to assist in determining the stock of fall chinook and chum spawning and rearing below Bonneville Dam. Based on observed spawning times, adult age and sex composition, juvenile emergence timing, juvenile migration timing and juvenile size at the time of migration, it appears that in 2003 all of the fall chinook using the area below Bonneville Dam were of a late-spawning, bright stock. Observed spawning times, adult age and sex composition, GSI and DNA analysis, juvenile emergence

  16. Matahina Dam : lessons learned from an earthquake-related internal erosion incident at the Matahina Dam, New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Gillon, M. [Damwatch Services Ltd., Wellington (New Zealand)

    2009-07-01

    This case history discussed internal erosion damage and crest subsidence caused by an earthquake at the Matahina Dam in New Zealand. The study showed that cracking and internal erosion was initiated during the 1967 reservoir filling operation. Located in an area of active volcanism and faulting, the dam is located on a river with extensive erosion through an ignimbrite flow. The dam's core is founded on compact Tertiary age sediments overlain by sand and gravel deposits beneath the shoulders of the dam. The earthquake caused a rupture along an unidentified fault trace 12 km from the dam. The horizontal base acceleration recorded at the dam was 3.25 m/s. Transverse cracking was observed at each abutment, and deformations were observed in the rockfill. An investigation program was conducted to determine the dam's integrity. Piezometer measurements showed widespread fluctuations. It was concluded that the lack of an effective filter was a significant design omission. 12 refs., 12 figs.

  17. Dam-breach analysis and flood-inundation mapping for selected dams in Oklahoma City, Oklahoma, and near Atoka, Oklahoma

    Science.gov (United States)

    Shivers, Molly J.; Smith, S. Jerrod; Grout, Trevor S.; Lewis, Jason M.

    2015-01-01

    Dams provide beneficial functions such as flood control, recreation, and storage of water supplies, but they also entail risk; dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or improper operation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning an emergency response if a dam breach occurs.

  18. Technical bulletin : structural considerations for dam safety

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This technical bulletin discussed issues related to the safety assessment of concrete water-retaining structures and timber dams. Structures reviewed in the paper included gravity dams; buttress dams; arch dams; spillway structures; intake structures; power plants; roller compacted concrete dams; and timber dams. A variety of issues related to the loss of cohesive bond and discontinuities in bedrock foundations were reviewed with reference to issues related to compressive strength, tensile strength, and shear strength. Static failure modes and failure mechanisms related to dam failures were also described. Visual indicators for potential failures include abutment and foundation movement, seepage, and structure movements. Loading combinations were discussed, and performance indicators for gravity dams were provided. Methods of analysis for considering load characteristics, structure types and geological conditions were also discussed. Modelling techniques for finite element analysis were also included. 16 refs., 3 tabs., 5 figs.

  19. Assessing Risks of Mine Tailing Dam Failures

    Science.gov (United States)

    Concha Larrauri, P.; Lall, U.

    2017-12-01

    The consequences of tailings dam failures can be catastrophic for communities and ecosystems in the vicinity of the dams. The failure of the Fundão tailings dam at the Samarco mine in 2015 killed 19 people with severe consequences for the environment. The financial and legal consequences of a tailings dam failure can also be significant for the mining companies. For the Fundão tailings dam, the company had to pay 6 billion dollars in fines and twenty-one executives were charged with qualified murder. There are tenths of thousands of active, inactive, and abandoned tailings dams in the world and there is a need to better understand the hazards posed by these structures to downstream populations and ecosystems. A challenge to assess the risks of tailings dams in a large scale is that many of them are not registered in publicly available databases and there is little information about their current physical state. Additionally, hazard classifications of tailings dams - common in many countries- tend to be subjective, include vague parameter definitions, and are not always updated over time. Here we present a simple methodology to assess and rank the exposure to tailings dams using ArcGIS that removes subjective interpretations. The method uses basic information such as current dam height, storage volume, topography, population, land use, and hydrological data. A hazard rating risk was developed to compare the potential extent of the damage across dams. This assessment provides a general overview of what in the vicinity of the tailings dams could be affected in case of a failure and a way to rank tailings dams that is directly linked to the exposure at any given time. One hundred tailings dams in Minas Gerais, Brazil were used for the test case. This ranking approach could inform the risk management strategy of the tailings dams within a company, and when disclosed, it could enable shareholders and the communities to make decisions on the risks they are taking.

  20. The socio-economics dynamics of Dam on Rural Communities: A case study of Oyan Dam, Nigeria

    Science.gov (United States)

    Ayeni, Amidu; Ojifo, Lawrence

    2018-06-01

    Dams construction and operations have many benefits, nevertheless, they have also led to lots of negative social, health and human impacts. It is based on this that this study assesses the potential and socio-economics dynamics of Oyan dam between 1980 and 2016. The data used for this study include water level and discharge records of the dam between 2007 and 2016, Landsat imageries of 1984 and 2016 and socio-economic datasets for the period. Analysis of the dam potentials (water supply, agriculture and hydropower) and socio-economic impacts of the dam were carried out using basic statistical tools, land use change anaysis and field survey using questionnaire, structured interview with major stakeholders and personal observation. The results revealed that the water level and storage of the Oyan dam had a relative reduction of about 2 % as well as non-stationarity pattern of water abstraction and production for the period. The landuse classes show all classes decreased in extent except the cultivated landuse that acrued an increased of 19.9 % between 1984 and 2016. Furthermore, commercial water supply varied significantly between 2010 and 2016 while irrigation scheme is grossly under-utilized from the inception in 1983 to 2016. Finally, the result of socio-economic impacts revealed that majority of the selected communities' members are actually not benefiting from the dam and their livelihoods are not from the dam.

  1. Sediment Transport Over Run-of-River Dams

    Science.gov (United States)

    O'Brien, M.; Magilligan, F. J.; Renshaw, C. E.

    2016-12-01

    Dams have numerous documented effects that can degrade river habitat downstream. One significant effect of large dams is their ability to trap sediment delivered from upstream. This trapping can alter sediment transport and grain size downstream - effects that often motivate dam removal decisions. However, recent indirect observations and modeling studies indicate that small, run-of-river (ROR) dams, which do not impede discharge, may actually leak sediment downstream. However, there are no direct measurements of sediment flux over ROR dams. This study investigates flow and sediment transport over four to six different New England ROR dams over a summer-fall field season. Sediment flux was measured using turbidity meters and tracer (RFID) cobbles. Sediment transport was also monitored through an undammed control site and through a river where two ROR dams were recently removed. These data were used to predict the conditions that contribute to sediment transport and trapping. Year 1 data show that tracer rocks of up to 61 mm were transported over a 3 m ROR dam in peak flows of 84% of bankfull stage. These tracer rocks were transported over and 10 m beyond the dam and continue to move downstream. During the same event, comparable suspended sediment fluxes of up to 81 g/s were recorded both upstream and downstream of the dam at near-synchronous timestamps. These results demonstrate the potential for sediment transport through dammed rivers, even in discharge events that do not exceed bankfull. This research elucidates the effects of ROR dams and the controls on sediment transport and trapping, contributions that may aid in dam management decisions.

  2. Hydraulics of embankment-dam breaching

    Science.gov (United States)

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

    2012-12-01

    Constructed or natural earthen dams can pose hazards to downstream communities. Experiments to date on earthen-dam breaching have focused on dam geometries relevant to engineering practice. We have begun experiments with dam geometries more like those of natural dams. Water was impounded behind dams constructed at the downstream end of the USGS debris-flow flume. Dams were made of compacted, well-sorted, moist beach sand (D50=0.21 mm), 3.5 m from toe to toe, but varying in height from 0.5 to 1 m; the lower the dam, the smaller the reservoir volume and the broader the initially flat crest. Breaching was started by cutting a slot 30-40 mm wide and deep in the dam crest after filling the reservoir. Water level and pore pressure within the dam were monitored. Experiments were also recorded by an array of still- and video cameras above the flume and a submerged video camera pointed at the upstream dam face. Photogrammetric software was used to create DEMs from stereo pairs, and particle-image velocimetry was used to compute the surface-velocity field from the motion of tracers scattered on the water surface. As noted by others, breaching involves formation and migration of a knickpoint (or several). Once the knickpoint reaches the upstream dam face, it takes on an arcuate form whose continued migration we determined by measuring the onset of motion of colored markers on the dam face. The arcuate feature, which can be considered the head of the "breach channel", is nearly coincident with the transition from subcritical to supercritical flow; that is, it acts as a weir that hydraulically controls reservoir emptying. Photogenic slope failures farther downstream, although the morphologically dominant process at work, play no role at all in hydraulic control aside from rare instances in which they extend upstream so far as to perturb the weir, where the flow cross section is nearly self-similar through time. The domain downstream of the critical-flow section does influence

  3. Dam that social networking: connecting South Africa's major dams to social media

    CSIR Research Space (South Africa)

    Butgereit, L

    2011-10-01

    Full Text Available where four major South African dams are connected to Twitter and Facebook (and other social media such as MXit and Google Chat) in a mechanism which would be easy to replicate for additional dams or rivers. Data is supplied by the South African...

  4. 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.

  5. Construction of anhydrite dams

    Energy Technology Data Exchange (ETDEWEB)

    Bortoluzzi, L; Francois, G

    1977-05-01

    To construct a ventilation dam, the road is closed with a fibreglass sheet onto which 3 or 4 cm of anhydrite paste is sprayed. The equipment necessary is described, and the cost is compared with that of an aggregate dam.

  6. Dams, Hydrology and Risk in Future River Management

    Science.gov (United States)

    Wegner, D. L.

    2017-12-01

    Across America there are over 80,000 large to medium dams and globally the number is in excess of 800,000. Currently there are over 1,400 dams and diversion structures being planned or under construction globally. In addition to these documented dams there are thousands of small dams populating watersheds. Governments, agencies, native tribes, private owners and regulators all have a common interest in safe dams. Often dam safety is characterized as reducing structural risk while providing for maximum operational flexibility. In the 1970's there were a number of large and small dam failures in the United States. These failures prompted the federal government to issue voluntary dam safety guidelines. These guidelines were based on historic information incorporated into a risk assessment process to analyze, evaluate and manage risk with the goal to improve the quality of and support of dam management and safety decisions. We conclude that historic and new risks need to be integrated into dam management to insure adequate safety and operational flexibility. A recent assessment of the future role of dams in the United States premises that future costs such as maintenance or removal beyond the economic design life have not been factored into the long-term operations or relicensing of dams. The converging risks associated with aging water storage infrastructure, multiple dams within watersheds and uncertainty in demands policy revisions and an updated strategic approach to dam safety. Decisions regarding the future of dams in the United States may, in turn, influence regional water planning and management. Leaders in Congress and in the states need to implement a comprehensive national water assessment and a formal analysis of the role dams play in our water future. A research and national policy agenda is proposed to assess future impacts and the design, operation, and management of watersheds and dams.

  7. Mitigating Dam Impacts Using Environmental Flow Releases

    Science.gov (United States)

    Richter, B. D.

    2017-12-01

    One of the most ecologically disruptive impacts of dams is their alteration of natural river flow variability. Opportunities exist 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. 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. This presentation will highlight 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 suggested strategies for dam re-operation are predicated on changes in the end-use of the water, such as reductions in urban or agricultural water use during droughts, a systemic perspective of entire water management systems will be required to attain the fullest possible

  8. Behind an ambitious megaproject in Asia: The history and implications of the Bakun hydroelectric dam in Borneo

    International Nuclear Information System (INIS)

    Sovacool, Benjamin K.; Bulan, L.C.

    2011-01-01

    Using a case-study, inductive, narrative approach, this article explores the history, drivers, benefits, and barriers to the Bakun Hydroelectric Project in East Malaysia. Situated on the island of Borneo, Bakun Dam is a 204 m high concrete face, rock filled dam on the Balui River in the Upper Rajang Basin in the rainforests of Sarawak. Bakun Dam and its affiliated infrastructure could be the single largest and most expensive energy project ever undertaken in Southeast Asia. Based on data collected through site visits, original field research in Sarawak, and more than 80 research interviews, the article begins by teasing out the complex history and drivers behind the Bakun project before identifying a set of potential social, political, and economic benefits the project could deliver. It then delves into six sets of barriers in the technical, economic, political, legal and regulatory, social, and environmental realms. We find that Bakun illustrates how centralized energy megaprojects, while ostensibly championed for reasons of economies of scale and the ability to bring about transformational change in the shortest period of time, often fail to address broader development goals such as fighting energy poverty and improving the livelihoods of the local communities they are supposed to serve. - Highlights: → Bakun Dam is concrete face, rock filled dam on the Balui River in the Upper Rajang Basin in the rainforests of Sarawak. → The project faces technical, economic, political, legal and regulatory, social, and environmental barriers. → We conclude the project will fail to fight energy poverty or improve the livelihoods of local populations.

  9. Behind an ambitious megaproject in Asia: The history and implications of the Bakun hydroelectric dam in Borneo

    Energy Technology Data Exchange (ETDEWEB)

    Sovacool, Benjamin K., E-mail: bsovacool@nus.edu.sg [Lee Kuan Yew School of Public Policy, National University of Singapore, Oei Tiong Ham Building, 469C Bukit Timah Road, Singapore 259772 (Singapore); Bulan, L.C. [Lee Kuan Yew School of Public Policy, National University of Singapore, Oei Tiong Ham Building, 469C Bukit Timah Road, Singapore 259772 (Singapore)

    2011-09-15

    Using a case-study, inductive, narrative approach, this article explores the history, drivers, benefits, and barriers to the Bakun Hydroelectric Project in East Malaysia. Situated on the island of Borneo, Bakun Dam is a 204 m high concrete face, rock filled dam on the Balui River in the Upper Rajang Basin in the rainforests of Sarawak. Bakun Dam and its affiliated infrastructure could be the single largest and most expensive energy project ever undertaken in Southeast Asia. Based on data collected through site visits, original field research in Sarawak, and more than 80 research interviews, the article begins by teasing out the complex history and drivers behind the Bakun project before identifying a set of potential social, political, and economic benefits the project could deliver. It then delves into six sets of barriers in the technical, economic, political, legal and regulatory, social, and environmental realms. We find that Bakun illustrates how centralized energy megaprojects, while ostensibly championed for reasons of economies of scale and the ability to bring about transformational change in the shortest period of time, often fail to address broader development goals such as fighting energy poverty and improving the livelihoods of the local communities they are supposed to serve. - Highlights: > Bakun Dam is concrete face, rock filled dam on the Balui River in the Upper Rajang Basin in the rainforests of Sarawak. > The project faces technical, economic, political, legal and regulatory, social, and environmental barriers. > We conclude the project will fail to fight energy poverty or improve the livelihoods of local populations.

  10. A genetic linkage map of willow (Salix viminalis) based on AFLP and microsatelite markers

    NARCIS (Netherlands)

    Hanley, S.; Barker, J.H.A.; Ooijen, van J.W.; Aldam, C.; Harris, S.L.; Ahman, I.; Larsson, S.; Karp, A.

    2002-01-01

    The genus Salix (willow) contains a number of species of great value as biomass crops. Efforts to breed varieties with improved biomass yields and resistances to pests and diseases are limited by the lack of knowledge on the genetic basis of the traits. We have used AFLP and microsatellite markers

  11. Simulation of Breach Outflow for Earthfill Dam

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  12. Restoring Environmental Flows by Modifying Dam Operations

    Directory of Open Access Journals (Sweden)

    Brian D. Richter

    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

  13. 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

  14. Brazil's Balbina Dam: Environment versus the legacy of the Pharaohs in Amazonia

    Science.gov (United States)

    Fearnside, Philip M.

    1989-07-01

    The Balbina Dam in Brazil's state of Amazonas floods 2360 km2 of tropical forest to generate an average of only 112.2 MW of electricity. The flat topography and small size of the drainage basin make output small. Vegetation has been left to decompose in the reservoir, resulting in acidic, anoxic water that will corrode the turbines. The shallow reservoir contains 1500 islands and innumerable stagnant bays where the water's residence time will be even longer than the average time of over one year. Balbina was built to supply electricity to Manaus, a city that has grown so much while the dam was under construction that other alternatives are already needed. Government subsidies explain the explosive growth, including Brazil's unified tariff for electricity. Alternative power sources for Manaus include transmission from more distant dams or from recently discovered oil and natural gas deposits. Among Balbina's impacts are loss of potential use of the forest and displacement of about one third of the surviving members of a much-persecuted Amerindian tribe: the Waimiri-Atroari. The dam was closed on 1 October 1987 and the first of five generators began operation in February 1989. The example of Balbina points to important ways that the decision-making process could be improved in Brazil and in the international funding agencies that have directly and indirectly contributed to the project. Environmental impact analyses must be completed prior to decisions on overall project implementation and must be free of influence from project proponents. The current environmental impact assessment system in Brazil, as in many other countries, has an undesirable influence on science policy, in addition to failing to address the underlying causes of environmentally destructive development processes and inability to halt “irreversible” projects like Balbina.

  15. Effects of seismic lines on the abundance of breeding birds in the Kendall Island Bird Sanctuary, Northwest Territories, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Ashenhurst, A.R.; Hannon, S.J. [Alberta Univ., Edmonton, AB (Canada). Dept. of Biological Sciences

    2008-06-15

    The effects of oil and gas exploration activities on bird abundance in the Arctic were investigated. The study examined the impacts of new and oil visible seismic lines within the Kendall Island Bird Sanctuary on the abundance of breeding passerines, Lapland longspur, common redpoll, American tree sparrow, and red-necked phalarope in upland tundra region and sedge-willow habitats. Results of the study showed that the effects on abundance with newer seismic lines were not statistically significant for most groups of birds. However, more birds were seen on reference transects than on seismic lines. The seismic lines had a significant impact on passerines grouped in upland tundra, as well as for sparrows in sedge and willows. Along older seismic lines, passerine abundance was lower than on reference transects in upland tundra. The study demonstrated that seismic lines created between 10 and 30 years ago had persistent vegetative changes that have reduced bird abundance. It was concluded that although the birds were not avoiding lines, some birds appeared to have increased the size of their territories in order to compensate for vegetative changes. 34 refs., 4 tabs.

  16. Seismic modelling of coal bed methane strata, Willow Creek, Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, S.E.; Mayer, R.; Lawton, D.C.; Langenberg, W. [Consortium for Research in Elastic Wave Exploration Seismology, Calgary, AB (Canada)

    2001-07-01

    The purpose is to determine the feasibility of applying high- resolution reflection seismic surveying to coalbed methane (CBM) exploration and development. Numerical reflection seismic methods are examined for measuring the mapping continuity and coherence of coal zones. Numerical modelling of a coal zone in Upper Cretaceous sediments near Willow Creek, Alberta indicates that seismic data that is predominantly of 100 Hz is required to map the coal zone and lateral facies variations within the deposit. For resolution of individual coal seams, a central frequency >150 Hz would be needed. 26 refs., 17 figs., 3 tabs.

  17. 33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...

    Science.gov (United States)

    2010-07-01

    ... River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). 100.1102 Section... MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.1102 Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam (Parker, Arizona). (a) General. Sponsors are...

  18. 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 environmental and socioeconomic impacts. Loss of forest to flooding is one, the Balbina and Tucuruí Dams being examples (each 3000 km2). If the Babaquara/Altamira Dam is built it will flood as much forest as both of these combined. Some planned dams imply loss of forest in protected areas, for example on the Tapajós River. Aquatic and riparian ecosystems are lost, including unique biodiversity. Endemic fish species in rapids on the Xingu and Tapajós Rivers are examples. Fish migrations are blocked, such as the commercially important "giant catfish" of the Madeira River. Dams emit greenhouse gases, including CO2 from the trees killed and CH4 from decay under anoxic conditions at the bottom of reservoirs. Emissions can exceed those from fossil-fuel generation, particularly over the 20-year period during which global emissions must be greatly reduced to meet 1.5-2°C limit agreed in Paris. Carbon credit for dams under the Climate Convention causes further net emission because the dams are not truly "additional." Anoxic environments in stratified reservoirs cause methylation of mercury present in Amazonian soils, which concentrates in fish, posing a health risk to human 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

  19. Behavior and dam passage of juvenile Chinook salmon at Cougar Reservoir and Dam, Oregon, March 2011 - February 2012

    Science.gov (United States)

    Beeman, John W.; Hansel, Hal C.; Hansen, Amy C.; Haner, Philip V.; Sprando, Jamie M.; Smith, Collin D.; Evans, Scott D.; Hatton, Tyson W.

    2013-01-01

    The movements and dam passage of juvenile Chinook salmon implanted with acoustic transmitters and passive integrated transponder tags were studied at Cougar Reservoir and Dam, near Springfield, Oregon. The purpose of the study was to provide information to aid with decisions about potential alternatives for improving downstream passage conditions for juvenile salmonids in this flood-control reservoir. In 2011, a total of 411 hatchery fish and 26 wild fish were tagged and released during a 3-month period in the spring, and another 356 hatchery fish and 117 wild fish were released during a 3-month period in the fall. A series of 16 autonomous hydrophones throughout the reservoir and 12 hydrophones in a collective system near the dam outlet were used to determine general movements and dam passage of the fish over the life of the acoustic transmitter, which was expected to be about 3 months. Movements within the reservoir were directional, and it was common for fish to migrate repeatedly from the head of the reservoir downstream to the dam outlet and back to the head of the reservoir. Most fish were detected near the temperature control tower at least once. The median time from release near the head of the reservoir to detection within about 100 meters of the dam outlet at the temperature control tower was between 5.7 and 10.8 days, depending on season and fish origin. Dam passage events occurred over a wider range of dates in the spring and summer than in the fall and winter, but dam passage numbers were greatest during the fall and winter. A total of 10.5 percent (43 of 411) of the hatchery fish and 15.4 percent (4 of 26) of the wild fish released in the spring are assumed to have passed the dam, whereas a total of 25.3 percent (90 of 356) of the hatchery fish and 16.9 percent (30 of 117) of the wild fish released in the fall are assumed to have passed the dam. A small number of fish passed the dam after their transmitters had stopped working and were detected at

  20. Microbial expression profiles in the rhizosphere of willows depend on soil contamination

    OpenAIRE

    Yergeau, Etienne; Sanschagrin, Sylvie; Maynard, Christine; St-Arnaud, Marc; Greer, Charles W

    2013-01-01

    The goal of phytoremediation is to use plants to immobilize, extract or degrade organic and inorganic pollutants. In the case of organic contaminants, plants essentially act indirectly through the stimulation of rhizosphere microorganisms. A detailed understanding of the effect plants have on the activities of rhizosphere microorganisms could help optimize phytoremediation systems and enhance their use. In this study, willows were planted in contaminated and non-contaminated soils in a greenh...

  1. Dams and Intergovernmental Transfers

    Science.gov (United States)

    Bao, X.

    2012-12-01

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

  2. GIS inundation mapping and dam breach analysis of Woolwich Dam using HEC-geoRAS

    Energy Technology Data Exchange (ETDEWEB)

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada); Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)

    2006-07-01

    A study was conducted to determine the extent of flood inundation given a hypothetical dam breach scenario of the Woolwich Dam located in the Grand River Watershed, 2.5 km north of the Town of Elmira, Ontario. The dam is operated by the Grand River Conservation Authority and was constructed to provide low-flow augmentation to Canagagigue Creek. Advances in the computational capabilities of numerical models along with the availability of fine resolution geospatial data has lead to significant advances in the evaluation of catastrophic consequences due to the ensuing flood waters when dams fail. The hydraulic models HEC-RAS and HEC-GeoRAS were used in this study along with GIS to produce high resolution spatial and temporal flood inundation mapping. Given the proximity to the Town of Elmira, the dam is classified as having a high hazard potential. The large size and high hazard potential of the dam suggests that the Inflow Design Flood (IDF) is the Probable Maximum Flood (PMF) event. The outlet structure of the spillway consists of 4 ogee-type concrete spillways equipped with radial gates. A low-level concrete pipe located within the spillway structure provides spillage for maintenance purposes. The full flow capacity of the spillway structure is 297 cubic metres per second at the full supply level of 364.8 metres. In addition to GIS flood inundation maps, this paper included the results of flood hydrographs, water surface profiles and peak flow data. It was concluded that techniques used in this analysis should be considered for use in the development of emergency management planning and dam safety assessments across Canada. 6 refs., 3 tabs., 4 figs.

  3. Porous Carbon with Willow-Leaf-Shaped Pores for High-Performance Supercapacitors.

    Science.gov (United States)

    Shi, Yanhong; Zhang, Linlin; Schon, Tyler B; Li, Huanhuan; Fan, Chaoying; Li, Xiaoying; Wang, Haifeng; Wu, Xinglong; Xie, Haiming; Sun, Haizhu; Seferos, Dwight S; Zhang, Jingping

    2017-12-13

    A novel kind of biomass-derived, high-oxygen-containing carbon material doped with nitrogen that has willow-leaf-shaped pores was synthesized. The obtained carbon material has an exotic hierarchical pore structure composed of bowl-shaped macropores, willow-leaf-shaped pores, and an abundance of micropores. This unique hierarchical porous structure provides an effective combination of high current densities and high capacitance because of a pseudocapacitive component that is afforded by the introduction of nitrogen and oxygen dopants. Our synthetic optimization allows further improvements in the performance of this hierarchical porous carbon (HPC) material by providing a high degree of control over the graphitization degree, specific surface area, and pore volume. As a result, a large specific surface area (1093 m 2 g -1 ) and pore volume (0.8379 cm 3 g -1 ) are obtained for HPC-650, which affords fast ion transport because of its short ion-diffusion pathways. HPC-650 exhibits a high specific capacitance of 312 F g -1 at 1 A g -1 , retaining 76.5% of its capacitance at 20 A g -1 . Moreover, it delivers an energy density of 50.2 W h kg -1 at a power density of 1.19 kW kg -1 , which is sufficient to power a yellow-light-emitting diode and operate a commercial scientific calculator.

  4. 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.

  5. Assessing survival of Mid-Columbia River released juvenile salmonids at McNary Dam, Washington, 2008-09

    Science.gov (United States)

    Evans, Scott D.; Walker, Christopher E.; Brewer, Scott J.; Adams, Noah S.

    2010-01-01

    Few studies have evaluated survival of juvenile salmon over long river reaches in the Columbia River and information regarding the survival of sockeye salmon at lower Columbia River dams is lacking. To address these information gaps, the U.S. Geological Survey was contracted by the U.S. Army Corps of Engineers to evaluate the possibility of using tagged fish released in the Mid-Columbia River to assess passage and survival at and downstream of McNary Dam. Using the acoustic telemetry systems already in place for a passage and survival study at McNary Dam, fish released from the tailraces of Wells, Rocky Reach, Rock Island, Wanapum, and Priest Rapids Dams were detected at McNary Dam and at the subsequent downstream arrays. These data were used to generate route-specific survival probabilities using single-release models from fish released in the Mid-Columbia River. We document trends in passage and survival probabilities at McNary Dam for yearling Chinook and sockeye salmon and juvenile steelhead released during studies in the Mid-Columbia River. Trends in the survival and passage of these juvenile salmonid species are presented and discussed. However, comparisons made across years and between study groups are not possible because of differences in the source of the test fish, the type of acoustic tags used, the absence of the use of passive integrated transponder tags in some of the release groups, differences in tagging and release protocols, annual differences in dam operations and configurations, differences in how the survival models were constructed (that is, number of routes that could be estimated given the number of fish detected), and the number and length of reaches included in the analysis (downstream reach length and arrays). Despite these differences, the data we present offer a unique opportunity to examine the migration behavior and survival of a group of fish that otherwise would not be studied. This is particularly true for sockeye salmon because

  6. The World Commission on Dams + 10: Revisiting the Large Dam Controversy

    Directory of Open Access Journals (Sweden)

    Deborah Moore

    2010-06-01

    Full Text Available The World Commission on Dams (WCD was an experiment in multi-stakeholder dialogue and global governance concerned with a subject area – large dams – that was fraught with conflict and controversy. The WCD Report, Dams and Development: A New Framework for Decision-Making, was published in 2000 and accompanied by hopes that broad-based agreements would be forged on how to better manage water and energy development. Ten years later, this special issue of Water Alternatives revisits the WCD and its impacts, exploring the question: Is the WCD still relevant? The editorial team and the Guest Editors of this special issue of Water Alternatives have selected a range of 20 papers, 6 viewpoints, and 4 book reviews that help to illustrate the evolution in the dams debate. The goal of this special issue is to examine the influence and the impacts of the WCD on the dam enterprise, in general, and on the policies and practices of key stakeholders and institutions, and on the development outcomes for affected communities and environments, in particular. In this introduction, the Guest Editors provide an overview of the special issue, exploring the new drivers of dam development that have emerged during the last decade, including climate change and new financiers of dams, and describing the themes emerging from this diverse set of papers and viewpoints. This special issue demonstrates the need for a renewed multi-stakeholder dialogue at multiple levels. This would not be a redo of the WCD, but rather a rekindling and redesigning of processes and forums where mutual understanding, information-sharing, and norm-setting can occur. One of the most promising developments of the last decade is the further demonstration, in case studies described here, that true partnership amongst key stakeholders can produce transformative resource-sharing agreements, showing that many of the WCD recommendations around negotiated decision making are working in practice. We hope

  7. Rainwater Management Model Development for Agriculture in the Savu Island Semi-Arid Region

    Directory of Open Access Journals (Sweden)

    Susilawati C.L.

    2012-01-01

    Full Text Available Savu Island is a semiarid region with few rainfalls. The meager annual rainfall of about 1,000-1,500 mm that lasts for three to five months tends to cause draught. To cope with this situation, the Author tries to develop a rainwater management model located in Daieko village. This model constitutes an infrastructure that consists of check dam series which are constructed by simulating a computerized model of decision supporting system called “Rainwater Management for Agriculture Decision Support System (RMA-DSS model” in the research location of Daieko village. Employing a simulated RMA-DSS model; the locations for check-dam series, and dug-wells can be determined, the size of potential irrigable lands can be determined based on water balance analysis of water samples taken from simulated check dams and inundated lands. Through this model the sufficiency of water supply for agricultural purposes and the land size for cultivation area can be predicted with a high degree of certainty.

  8. Research progress on dam-break floods

    KAUST Repository

    Wu, Jiansong; Bao, Kai; Zhang, Hui

    2011-01-01

    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.

  9. 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.

  10. Tenaga Nasional Berhad dam safety and surveillance program

    International Nuclear Information System (INIS)

    Jansen Luis; Zulkhairi Abd Talib

    2006-01-01

    This paper discusses the current practice of dam surveillance, which includes dam monitoring which is a process of visual inspections, measuring, processing, compiling and analyzing dam instrumentation data to determine the performance of a dam. The prime objective of the dam surveillance system is to ensure that any occurrence and development of safety deficiencies and problems are quickly detected, identified, analyzed and the required remedial actions are determined and consequently carried out in due time. In brief, the section is responsible to ensure that the dam monitoring and surveillance works are implemented as per scheduled and in accordance with the requirement and guidelines prepared by the dam designers and in accordance with international commission on large dams, ICOLD. The paper also illustrates and recommends an alternative approach for dam surveillance program using risk management approach, which is currently being actively adopted by some countries like USA, Canada, Australia and etc, towards improving the dam safety management and the decision making process. The approach provides a wider area of opportunity, improvements and benefits particular in the evaluation and modifications to the dam performance and safety. The process provides an effective and efficient tool for the decision makers and engineers through a comprehensive evaluation and a good understanding of the hazards, risks and consequences in relation to dam safety investigations. (Author)

  11. National Program for Inspection of Non-Federal Dams. Babson Reservoir Dam (MA 00187), Massachusetts-Rhode Island Coastal Basin, Gloucester, Massachusetts. Phase I Inspection Report.

    Science.gov (United States)

    1978-11-01

    DIVISION, CORPS OF ENGINEERSWALTHAM, MASS 02154 NTIS GRA&n F NOVEMBER 1978 DTIC TAB Ŕ Justiftcati n r r D stributijon/ Availabilit -" os Dist jSpecial...flashboards removed and can pass the PMF outflow of 1530 cfs (750 csm) with the water level 0.6 ft.Ui below the top of the concrete core wall. Within... water treatment plant and responsible for the day-to-day operation of the dam. He represented the owner during this investigation. His address and

  12. Quantifying the Behavioral Response of Spawning Chum Salmon to Elevated Discharges from Bonneville Dam, Columbia River : Annual Report 2005-2006.

    Energy Technology Data Exchange (ETDEWEB)

    Tiffan, Kenneth F.; Haskell, Craig A.; Kock, Tobias J.

    2008-12-01

    In unimpounded rivers, Pacific salmon (Oncorhynchus spp.) typically spawn under relatively stable stream flows, with exceptions occurring during periodic precipitation events. In contrast, hydroelectric development has often resulted in an artificial hydrograph characterized by rapid changes in discharge and tailwater elevation that occur on a daily, or even an hourly basis, due to power generation (Cushman 1985; Moog 1993). Consequently, populations of Pacific salmon that are known to spawn in main-stem habitats below hydroelectric dams face the risks of changing habitat suitability, potential redd dewatering, and uncertain spawning success (Hamilton and Buell 1976; Chapman et al. 1986; Dauble et al. 1999; Garland et al. 2003; Connor and Pflug 2004; McMichael et al. 2005). Although the direct effects of a variable hydrograph, such as redd dewatering are apparent, specific effects on spawning behavior remain largely unexplored. Chum salmon (O. keta) that spawn below Bonneville Dam on the Columbia River are particularly vulnerable to the effects of water level fluctuations. Although chum salmon generally spawn in smaller tributaries (Johnson et al. 1997), many fish spawn in main-stem habitats below Bonneville Dam near Ives Island (Tomaro et al. 2007; Figure 1). The primary spawning area near Ives Island is shallow and sensitive to changes in water level caused by hydroelectric power generation at Bonneville Dam. In the past, fluctuating water levels have dewatered redds and changed the amount of available spawning habitat (Garland et al. 2003). To minimize these effects, fishery managers attempt to maintain a stable tailwater elevation at Bonneville Dam of 3.5 m (above mean sea level) during spawning, which ensures adequate water is provided to the primary chum salmon spawning area below the mouth of Hamilton Creek (Figure 1). Given the uncertainty of winter precipitation and water supply, this strategy has been effective at restricting spawning to a specific

  13. WinDAM C earthen embankment internal erosion analysis software

    Science.gov (United States)

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

  14. Proceedings of the Canadian Dam Association's 2005 annual conference : 100 years of dam experience : balancing tradition and innovation. CD-ROM ed.

    International Nuclear Information System (INIS)

    2004-09-01

    This conference provided a forum to promote discussion on improving the management and safety of dams. It featured 8 technical sessions as well as workshops to discuss dam safety guidelines and guidelines for extreme flood analyses and their applications. It also featured workshops on instrumentation and performance monitoring of dams; tailing dam closures and reclamation; and, practical approaches to emergency preparedness for dam owners. The discussions provided details on large hydropower development projects, their innovations in environmental impact assessment, mitigation, and monitoring. The conference included a technical component led by experts on dams and tailings facilities. Recent developments in dam construction were reviewed along with discharge and debris management, tailings dam issues, asset management, seismic issues, public safety, seepage monitoring, flow control, dam rehabilitation, concrete testing, hydrotechnical issues, risk assessment methodology, and safety guidelines. All 24 presentations at this conference have been catalogued separately for inclusion in this database

  15. Sinkhole remediation at Swinging Bridge Dam

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A. [Devine Tarbell and Associates, Portland, ME (United States)

    2009-07-01

    This case history summary described a piping-related sinkhole that occurred after a flood at the Swinging Bridge Dam. The earth-filled embankment dam was constructed using a hydraulic fill technique. A foundation drilling and grouting program was constructed in areas of the dam founded on jointed sandstone and shale. The storage volumes of the reservoir is 32,000 acre-feet. A sinkhole 25 to 300 feet in diameter was observed on May 5, 2005 along the edge of the dam crest. The sinkhole extended to within 10 feet of the reservoir and was separated by a shallow berm of soil and driftwood. Cracking of the crest extended across an area of 180 feet. Operations staff notified the appropriate agencies, implemented a monitoring program, and mobilized construction equipment and sands for use as emergency sinkhole filler. An increase in tailrace turbidity was observed. Historical records for the dam showed significant cracking during the initial filling of the reservoir. Failure modes included increased pore pressures and seepages resulting in the piping of soil along the outside of the dam conduit. Emergency repairs included chemical grouting and weld repairs in the penstocks. A Federal Emergency Management Agency (FEMA) is currently addressing safety issues associated with conduits through dams. 4 refs., 11 figs.

  16. Paleoseismology of the Nephi Segment of the Wasatch Fault Zone, Juab County, Utah - Preliminary Results From Two Large Exploratory Trenches at Willow Creek

    Science.gov (United States)

    Machette, Michael N.; Crone, Anthony J.; Personius, Stephen F.; Mahan, Shannon; Dart, Richard L.; Lidke, David J.; Olig, Susan S.

    2007-01-01

    In 2004, we identified a small parcel of U.S. Forest Service land at the mouth of Willow Creek (about 5 km west of Mona, Utah) that was suitable for trenching. At the Willow Creek site, which is near the middle of the southern strand of the Nephi segment, the WFZ has vertically displaced alluvial-fan deposits >6-7 m, forming large, steep, multiple-event scarps. In May 2005, we dug two 4- to 5-m-deep backhoe trenches at the Willow Creek site, identified three colluvial wedges in each trench, and collected samples of charcoal and A-horizon organic material for AMS (acceleration mass spectrometry) radiocarbon dating, and sampled fine-grained eolian and colluvial sediment for luminescence dating. The trenches yielded a stratigraphic assemblage composed of moderately coarse-grained fluvial and debris-flow deposits and discrete colluvial wedges associated with three faulting events (P1, P2, and P3). About one-half of the net vertical displacement is accommodated by monoclinal tilting of fan deposits on the hanging-wall block, possibly related to massive ductile landslide deposits that are present beneath the Willow Creek fan. The timing of the three surface-faulting events is bracketed by radiocarbon dates and results in a much different fault chronology and higher slip rates than previously considered for this segment of the Wasatch fault zone.

  17. Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees

    DEFF Research Database (Denmark)

    Nielsen, Mette Algreen; Trapp, Stefan; Rein, Arno

    2014-01-01

    The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from...

  18. A habitat overlap analysis derived from Maxent for Tamarisk and the South-western Willow Flycatcher

    Science.gov (United States)

    Patricia York; Paul Evangelista; Sunil Kumar; James Graham; Curtis Flather; Thomas Stohlgren

    2011-01-01

    Biologic control of the introduced and invasive, woody plant tamarisk (Tamarix spp, saltcedar) in south-western states is controversial because it affects habitat of the federally endangered South-western Willow Flycatcher (Empidonax traillii extimus). These songbirds sometimes nest in tamarisk where floodplain-level invasion replaces native habitats. Biologic control...

  19. Dynamic tests at the Outardes 3 dam

    International Nuclear Information System (INIS)

    Proulx, J.; Paultre, P.; Duron, Z.; Tai Mai Phat; Im, O.

    1992-01-01

    At the Outardes 3 gravity dam, part of the Manicouagan-Outardes hydroelectric complex in northeastern Quebec, forced vibration tests were carried out using an eccentric mass shaker attached to the dam crest at three different locations. Accelerations were measured along the crest and in the inspection galleries, and hydrodynamic pressures were measured along the upstream dam face and at various locations in the reservoir. The tests were designed to analyze the effects of gravity dam-reservoir interactions and to generate a data base for calibrating finite element models used in studying the dynamic behavior of gravity dams. Experimental results are presented in order to demonstrate the quality of the data obtained and the effectiveness of the experimental procedures. Modes of vibration were observed which corresponded to those obtained by finite element analysis. It is shown that techniques recently developed for dynamic tests on large dams can be successfully used on gravity dams. 3 refs., 6 figs

  20. Modeling the capacity of riverscapes to support beaver dams

    Science.gov (United States)

    Macfarlane, William W.; Wheaton, Joseph M.; Bouwes, Nicolaas; Jensen, Martha L.; Gilbert, Jordan T.; Hough-Snee, Nate; Shivik, John A.

    2017-01-01

    The construction of beaver dams facilitates a suite of hydrologic, hydraulic, geomorphic, and ecological feedbacks that increase stream complexity and channel-floodplain connectivity that benefit aquatic and terrestrial biota. Depending on where beaver build dams within a drainage network, they impact lateral and longitudinal connectivity by introducing roughness elements that fundamentally change the timing, delivery, and storage of water, sediment, nutrients, and organic matter. While the local effects of beaver dams on streams are well understood, broader coverage network models that predict where beaver dams can be built and highlight their impacts on connectivity across diverse drainage networks are lacking. Here we present a capacity model to assess the limits of riverscapes to support dam-building activities by beaver across physiographically diverse landscapes. We estimated dam capacity with freely and nationally-available inputs to evaluate seven lines of evidence: (1) reliable water source, (2) riparian vegetation conducive to foraging and dam building, (3) vegetation within 100 m of edge of stream to support expansion of dam complexes and maintain large colonies, (4) likelihood that channel-spanning dams could be built during low flows, (5) the likelihood that a beaver dam is likely to withstand typical floods, (6) a suitable stream gradient that is neither too low to limit dam density nor too high to preclude the building or persistence of dams, and (7) a suitable river that is not too large to restrict dam building or persistence. Fuzzy inference systems were used to combine these controlling factors in a framework that explicitly also accounts for model uncertainty. The model was run for 40,561 km of streams in Utah, USA, and portions of surrounding states, predicting an overall network capacity of 356,294 dams at an average capacity of 8.8 dams/km. We validated model performance using 2852 observed dams across 1947 km of streams. The model showed

  1. The neutral species of the weak base trimethoprim is more toxic to willow trees (Salix viminalis) than the cation

    DEFF Research Database (Denmark)

    Mikes, O.; Trapp, Stefan

    2011-01-01

    The acute toxicity of the veterinary antibiotic trimethoprim (TMP) to willow trees was tested at three different pH levels in hydroponic solutions with TMP concentrations of 1, 10, 100 or 1000 mg/L. The pH variation was achieved by using ammonium (pH 4.3, low) or nitrate (pH 6.4, medium) as nitro......The acute toxicity of the veterinary antibiotic trimethoprim (TMP) to willow trees was tested at three different pH levels in hydroponic solutions with TMP concentrations of 1, 10, 100 or 1000 mg/L. The pH variation was achieved by using ammonium (pH 4.3, low) or nitrate (pH 6.4, medium...

  2. National dam inventory provides data for analysis

    International Nuclear Information System (INIS)

    Spragens, L.

    1992-01-01

    The Association of State Dam Safety Officials completed a dam inventory this fall. Information on approximately 90,000 state-regulated dams in the US collected during the four-year inventory is being used to build a database managed by the Federal Emergency Management Agency. In addition to ASDSO's work, the federal government conducted an inventory of federal dams. This data will be added to the state information to form one national database. The database will feature 35 data fields for each entry, including the name of the dam, its size, the name of the nearest downstream community, maximum discharge and storage volume, the date of the last inspection, and details about the emergency action plan. The program is an update of the nation's first dam inventory, required by the Dam Safety Act of 1972. The US Army Corps of Engineers completed the original inventory in 1981. The Water Resources Development Act of 1986 authorized appropriations of $2.5 million for the Corps to update the inventory. FEMA and the Corps entered into an agreement for FEMA to undertake the task for the Corps and to coordinate work on both the federal and state inventories. ASDSO compiles existing information on state-regulated dams into a common format for the database, added missing information, and established a process for continually updating data. ASDSO plans to analyze the information collected for the database. It will look at statistics for the number of dams regulated, communities that could be affected, and the number of high-hazard dams. FEMA is preparing reports for Congress on the project. The reports, which are expected to be ready by May 1993, will include information on the methodology used and facts about regulated dams under state jurisdiction

  3. Impacts of paper sludge and manure on soil and biomass production of willow

    International Nuclear Information System (INIS)

    Quaye, Amos K.; Volk, Timothy A.; Hafner, Sasha; Leopold, Donald J.; Schirmer, Charles

    2011-01-01

    Land application of organic wastes to short rotation woody crops (SRWC) can reduce the environmental impacts associated with waste disposal and enhance the productivity of biomass production systems. Understanding the potential impacts of organic amendments however, requires the examination of changes in soil characteristics and plant productivity. This study was conducted to evaluate the effect of paper sludge and dairy manure on biomass production of shrub willow (Salix dasyclados SV1) and to determine the impacts of these amendments on soil chemical properties. Treatments included urea, dairy manure and paper sludge separately and in combination, and a control. These materials were applied in the summer of 2005 to two fields of SV1 at different stages of growth: An old field with one year old shoots on a 10 year old root system and a young field which was beginning regrowth after being coppiced at the end of its first growing season. Foliar nutrient concentrations and soil chemical properties were analyzed at the end of the second growing season after treatment application to determine plant response to the fertilization regimes and to determine the effects of fertilization on soil characteristics. Fertilization did not increase biomass production in either field. However, application of the N-poor paper sludge did not reduce yield either. In general, fertilization did not influence soil or foliar chemistry, although there were some exceptions. The lack of response observed in this study is probably related to the nutrient status of the site or losses of applied nutrients. -- Highlights: → The fertilization treatments did not have any significant effect biomass production. → Application of paper sludge did not reduce willow biomass yield in both fields. → Foliar N concentration of willow crops in this study is in the range considered for optimal growth. → The limited response of foliar nutrients to fertilization indicates that the site was not limited by

  4. 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.

  5. Qu'Appelle River Dam, dam break analysis using advanced GIS tools for rapid modelling and inundation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Bonin, D. [Hatch Energy, Winnipeg, MB (Canada); Campbell, C. [Saskatchewan Watershed Authority, Moose Jaw, SK (Canada); Groeneveld, J. [Hatch Energy, Calgary, AB (Canada)

    2008-07-01

    The South Saskatchewan River Project (SSRP) comprises a multi-purpose reservoir that provides water for conservation and irrigation, flood control, power generation, recreation, and municipal and industrial water supply. In addition to the 64 m high Gardiner Dam, the 27 m high Qu'Appelle River Dam and the 22 km long Lake Diefenbaker Reservoir, the SSRP also includes ancillary works. The Qu'Appelle River valley extends for 458 km before connecting to the Assiniboine River. The valley is incised up to 90 m in depth and is a popular cottaging and recreational area with several major communities located in the flood plain. In the event of a breach of the Qu'Appelle Dam, the discharge will increase from a normal maximum discharge of under 60 m{sup 3} per second to over 50,000 m{sup 3} per second. The Saskatchewan Watershed Authority (SWA) is responsible for ensuring safe development of the Province's water resources, without affecting reservoir or lake operations, and preventing damage from flooding, erosion or land slides. It is in the process of developing Hazard Assessments and emergency preparedness plans for each of their dams in accordance with the Canadian Dam Safety Guidelines. Studies using GIS technology and the hydrodynamic routing model HEC-RAS have been completed to evaluate the potential inundation that may result in the event of failure of the Qu'Appelle River Dam. These studies involved the development of a breach parameter model using a breach data set revised to better reflect the Qu'Appelle River Dam; the development of a dam break model for the Qu'Appelle River Dam and downstream river and flood plain; and, the use of this model to simulate two potential dam failure scenarios for the Qu'Appelle River Dam, notably failure during passage of the PMF and failure during fair weather conditions. Inundation maps have been prepared for the downstream Qu'Appelle River valley for each of the above events. 3 refs., 4

  6. Assessment of the Influence of the Hydrological Regime of the Volga River on the Dynamics of Flooding on Sarpinsky Island

    Directory of Open Access Journals (Sweden)

    A.S. Rulev

    2017-03-01

    Full Text Available The seasonal dynamics of flooding on Sarpinsky Island, which is included in the city of Volgograd, following the damming by the Volga HPP has been considered. The following research problems have been set: firstly, to establish seasonal patterns of flooding in the island territory; secondly, to find out if there is a flooding threat to social infrastructure facilities. The flooded area of the island has been assessed by Landsat multispectral images with a spatial resolution of 30 m. Only images with the survey date corresponding to the peak of high waters (with the difference of not more than 7–10 days have been analyzed. The flooding areas of the island have been calculated for the date when flooding peaked (April–May during the period from 1985 to 2016. The phases of spring flooding determined by the island landscape and the water discharge from the Volga HPP have been revealed. The curve of the area of flooding reaches maximum values after the water discharge is up to 11–12 km3, which depends on the initial filling of floodplain reservoirs (landscape depressions in depth without any increase in the area of flooding. The average shift between the peaks of water discharge and the area of flooding is 10–15 days and reflects gradual filling of floodplain reservoirs on Sarpinsky Island after the beginning of water discharge from the Volga HPP. It has been found that there is no threat to infrastructure facilities on Sarpinsky Island under the current volumes of water discharge during the flooding period. The obtained results are important for urban planning on the island, as well as for management of the regimes of water passage through the dam of the Volga HPP.

  7. Dam Design can Impede Adaptive Management of Environmental Flows: A Case Study from the Opuha Dam, New Zealand

    Science.gov (United States)

    Lessard, JoAnna; Murray Hicks, D.; 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 m3 s-1 only three times; two of these floods exceeded the pre-dam mean annual flood of 203 m3 s-1 (compared to 19 times >100 m3 s-1 and 6 times >203 m3 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.

  8. The interplay of activists and dam developers : the case of Myanmar’s mega-dams

    NARCIS (Netherlands)

    Kirchherr, Julian|info:eu-repo/dai/nl/411261487; 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

  9. Concentrations of Chemical Elements in Willow Biomass Depend on Clone, Site and Management in the Field

    DEFF Research Database (Denmark)

    Liu, Na; Jørgensen, Uffe; Lærke, Poul Erik

    2016-01-01

    Eight willow (Salix) clones (Inger, Klara, Linnea, Resolution, Stina, Terra Nova, Tora, Tordis) were planted on two soil types in Denmark. The biomass quality was evaluated after 3 years of growth by measuring differences in concentrations of 14 elements associated with ash behavior during combus...

  10. Factors influencing hysteresis characteristics of concrete dam deformation

    Directory of Open Access Journals (Sweden)

    Jia-he Zhang

    2017-04-01

    Full Text Available Thermal deformation of a concrete dam changes periodically, and its variation lags behind the air temperature variation. The lag, known as the hysteresis time, is generally attributed to the low velocity of heat conduction in concrete, but this explanation is not entirely sufficient. In this paper, analytical solutions of displacement hysteresis time for a cantilever beam and an arch ring are derived. The influence of different factors on the displacement hysteresis time was examined. A finite element model was used to verify the reliability of the theoretical analytical solutions. The following conclusions are reached: (1 the hysteresis time of the mean temperature is longer than that of the linearly distributed temperature difference; (2 the dam type has a large impact on the displacement hysteresis time, and the hysteresis time of the horizontal displacement of an arch dam is longer than that of a gravity dam; (3 the reservoir water temperature variation lags behind of the air temperature variation, which intensifies the differences in the horizontal displacement hysteresis time between the gravity dam and the arch dam; (4 with a decrease in elevation, the horizontal displacement hysteresis time of a gravity dam tends to increase, whereas the horizontal displacement hysteresis time of an arch dam is likely to increase initially, and then decrease; and (5 along the width of the dam, the horizontal displacement hysteresis time of a gravity dam decreases as a whole, while the horizontal displacement hysteresis time of an arch dam is shorter near the center and longer near dam surfaces.

  11. 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.)

  12. A phytotoxicity test using transpiration of willows

    DEFF Research Database (Denmark)

    Trapp, Stefan; Zambrano, Kim Cecilia; Kusk, Kresten Ole

    2000-01-01

    is expressed as % decrease after 48 and 72 h or longer compared to the initial transpiration, divided by the transpiration of control plants. More toxicity parameters are growth and water use efficiency of the plants. The sensitivity of the test was evaluated with 3,5-dichlorophenol. EC50 values between 5......A short-term acute toxicity assay for willow trees growing in contaminated solution or in polluted soil was developed and tested. The test apparatus consists of an Erlenmeyer flask with a prerooted tree cutting growing in it. Growth and reduction of transpiration are used to determine toxicity....... Transpiration is closely related to photosynthesis and growth, but is easier and faster to measure and can be measured without disturbance of the test system. Plants are grown for 24 h in uncontaminated nutrient solution before the toxicant is added to determine the initial transpiration. The loss of weight...

  13. Ethyl lactate-EDTA composite system enhances the remediation of the cadmium-contaminated soil by Autochthonous Willow (Salix x aureo-pendula CL 'J1011') in the lower reaches of the Yangtze River

    International Nuclear Information System (INIS)

    Li Jiahua; Sun Yuanyuan; Yin Ying; Ji Rong; Wu Jichun; Wang Xiaorong; Guo Hongyan

    2010-01-01

    In order to explore a practical approach to the remediation of the cadmium (Cd)-contaminated soil in the lower reaches of the Yangtze River, we evaluated the effects of a local willow (Salix x aureo-pendula CL 'J1011') of absorbing, accumulating, and translocating Cd; and assessed the potential of chelator ethylenediaminetetraacetic acid (EDTA) in combination with ethyl lactate for enhancing the efficiency of the willow in removing Cd in two water-culture growth chamber trials and a field one. The willow showed a high tolerance to Cd in growth chamber trial 1 where the Cd concentration in the medium reached up to 25 mg L -1 medium, and the bioaccumulation factors (BAFs) of the shoots for Cd rose from 3.8 to 7.4 as the Cd concentration in the medium was elevated from 5 to 25 mg L -1 medium. In growth chamber trial 2, the average Cd removal rates in two treatments with EDTA and ethyl lactate (molar ratios of EDTA to ethyl lactate = 68/39 and 53.5/53.5, respectively) reached 0.71 mg d -1 pot -1 for the duration of Day 5-8 and 0.59 mg d -1 pot -1 for that of Day 8-11, which were 5- and 4-fold of their counterparts in the control, respectively. In the field trial, for the remediational duration of 45 days, three treatments-willow alone, willow combined with EDTA, and willow combined with EDTA and ethyl lactate-led to decreases in the Cd concentration in soil by 5%, 20%, and 29%, respectively; increases in that in the leaves by 14.6%, 56.7%, and 146.5%, respectively; and increases in that in the stems by 15.6%, 41.2%, and 87.4%, respectively, compared to their counterparts on Day 0. These results indicate that EDTA combined with ethyl lactate significantly enhanced the efficiency of willow in removing Cd from the soil. Therefore, a phytoextration system consisting of the autochthonous willow, EDTA, and ethyl lactate has high potential for the remediation of the Cd-polluted soil in the lower reaches of the Yangtze River.

  14. Ethyl lactate-EDTA composite system enhances the remediation of the cadmium-contaminated soil by autochthonous willow (Salix x aureo-pendula CL 'J1011') in the lower reaches of the Yangtze River.

    Science.gov (United States)

    Li, Jiahua; Sun, Yuanyuan; Yin, Ying; Ji, Rong; Wu, Jichun; Wang, Xiaorong; Guo, Hongyan

    2010-09-15

    In order to explore a practical approach to the remediation of the cadmium (Cd)-contaminated soil in the lower reaches of the Yangtze River, we evaluated the effects of a local willow (Salix x aureo-pendula CL 'J1011') of absorbing, accumulating, and translocating Cd; and assessed the potential of chelator ethylenediaminetetraacetic acid (EDTA) in combination with ethyl lactate for enhancing the efficiency of the willow in removing Cd in two water-culture growth chamber trials and a field one. The willow showed a high tolerance to Cd in growth chamber trial 1 where the Cd concentration in the medium reached up to 25 mg L(-1) medium, and the bioaccumulation factors (BAFs) of the shoots for Cd rose from 3.8 to 7.4 as the Cd concentration in the medium was elevated from 5 to 25 mg L(-1) medium. In growth chamber trial 2, the average Cd removal rates in two treatments with EDTA and ethyl lactate (molar ratios of EDTA to ethyl lactate=68/39 and 53.5/53.5, respectively) reached 0.71 mg d(-1) pot(-1) for the duration of Day 5-8 and 0.59 mg d(-1) pot(-1) for that of Day 8-11, which were 5- and 4-fold of their counterparts in the control, respectively. In the field trial, for the remediational duration of 45 days, three treatments-willow alone, willow combined with EDTA, and willow combined with EDTA and ethyl lactate-led to decreases in the Cd concentration in soil by 5%, 20%, and 29%, respectively; increases in that in the leaves by 14.6%, 56.7%, and 146.5%, respectively; and increases in that in the stems by 15.6%, 41.2%, and 87.4%, respectively, compared to their counterparts on Day 0. These results indicate that EDTA combined with ethyl lactate significantly enhanced the efficiency of willow in removing Cd from the soil. Therefore, a phytoextration system consisting of the autochthonous willow, EDTA, and ethyl lactate has high potential for the remediation of the Cd-polluted soil in the lower reaches of the Yangtze River. Copyright 2010 Elsevier B.V. All rights

  15. Integrated long-term responses of an arctic-alpine willow and associated ectomycorrhizal fungi to an altered environment

    DEFF Research Database (Denmark)

    Clemmensen, Karina Engelbrecht; Michelsen, Anders

    2006-01-01

    We evaluated ectomycorrhizal (ECM) colonization and morphotype community composition together with growth response and biomass distribution in the arctic-alpine, prostrate willow Salix herbacea L. x Salix polaris Wahlenb. after 11 seasons of shading, warming, and fertilization at a fellfield...

  16. Dam safety management in Victoria (Australia)

    International Nuclear Information System (INIS)

    Adem, J.

    1996-01-01

    The Victoria state government's decision to make dam owners accountable for safety and upkeep of their dams was reported. To give effect to this decision a series of guidelines have been developed which outline the required activities and skills to ensure that dams are properly managed within a framework of 'light-handed' regulation. The guidelines are also intended to ensure that dam management becomes an integral part of the business decision making process, not just a set of prescribed technical procedures. Details of the direction being taken and the proposed controls to ensure compliance with national and international standards were described. 4 refs., 2 figs

  17. Large Dam Effects on Flow Regime and Hydraulic Parameters of river (Case study: Karkheh River, Downstream of Reservoir Dam

    Directory of Open Access Journals (Sweden)

    Farhang Azarang

    2017-06-01

    Full Text Available Introduction: The critical role of the rivers in supplying water for various needs of life has led to engineering identification of the hydraulic regime and flow condition of the rivers. Hydraulic structures such dams have inevitable effects on their downstream that should be well investigated. The reservoir dams are the most important hydraulic structures which are the cause of great changes in river flow conditions. Materials and Methods: In this research, an accurate assessment was performed to study the flow regime of Karkheh river at downstream of Karkheh Reservoir Dam as the largest dam in Middle East. Karkheh River is the third waterful river of Iran after Karun and Dez and the third longest river after the Karun and Sefidrud. The Karkheh Dam is a large reservoir dam built in Iran on the Karkheh River in 2000. The Karkheh Reservoir Dam is on the Karkheh River in the Northwestern Khouzestan Province, the closest city being Andimeshk to the east. The part of Karkheh River, which was studied in this research is located at downstream of Karkheh Reservoir Dam. This interval is approximately 94 km, which is located between PayePol and Abdolkhan hydrometric stations. In this research, 138 cross sections were used along Karkheh River. Distance of cross sections from each other was 680m in average. The efficient model of HEC-RAS has been utilized to simulate the Karkheh flow conditions before and after the reservoir dam construction using of hydrometric stations data included annually and monthly mean discharges, instantaneous maximum discharges, water surface profiles and etc. Three defined discharges had been chosen to simulate the Karkheh River flow; maximum defined discharge, mean defined discharge and minimum defined discharge. For each of these discharges values, HEC-RAS model was implemented as a steady flow of the Karkheh River at river reach of study. Water surface profiles of flow, hydraulic parameters and other results of flow regime in

  18. 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.

  19. Measuring and managing safety at Wahleach Dam

    International Nuclear Information System (INIS)

    Salmon, G. M.; Cattanach, J. D.; Hartford, D. N. D.

    1996-01-01

    Safety improvements recently implemented at the Wahleach Dam were described as one of the first instances in international dam safety practice where risk concepts have been used in conjunction with acceptable risk criteria to evaluate safety of a dam relative to required level of safety. Erosion was identified as the greatest threat to the safety of the dam. In addressing the deficiencies B.C. Hydro formulated a process which advocates a balanced level of safety,i.e. the probability of failure multiplied by the consequences of failure, integrated over a range of initiators. If the risk posed by the dam is lower than a 'tolerable' risk, the dam is considered to be safe enough. In the case of the Wahleach Dam, the inflow design flood (IDF) was selected to be about one half of the probable maximum flow (PMF), hence it was more likely than not that the spillway could pass floods up to and including the PMF. By accepting the determined level of risk, expenditures of several million dollars for design and construction of dam safety improvements were made redundant. Another byproduct of this new concept of risk assessment was the establishment of improved life safety protection by means of an early warning system for severe floods through the downstream community and emergency authorities. 3 refs., 5 tabs

  20. Development of an applied black willow tree improvement program for biomass production in the south

    Science.gov (United States)

    Randall J. Rousseau; Emile S. Gardiner; Theodor D. Leininger

    2012-01-01

    The development of rapidly growing biomass woody crops is imperative as the United States strives to meet renewable energy goals. The Department of Energy has indicated that biomass is a prime source for renewable energy for the southern United States. Black Willow (Salix nigra Marsh.) is a potential bioenergy/biofuels crop for dedicated short-...

  1. Large dams and alluvial rivers in the Anthropocene: The impacts of the Garrison and Oahe Dams on the Upper Missouri River

    Science.gov (United States)

    Skalak, Katherine; Benthem, Adam J.; Schenk, Edward R.; Hupp, Cliff R.; Galloway, Joel M.; Nustad, Rochelle A.; Wiche, Gregg J.

    2013-01-01

    The Missouri River has had a long history of anthropogenic modification with considerable impacts on river and riparian ecology, form, and function. During the 20th century, several large dam-building efforts in the basin served the needs for irrigation, flood control, navigation, and the generation of hydroelectric power. The managed flow provided a range of uses, including recreation, fisheries, and habitat. Fifteen dams impound the main stem of the river, with hundreds more on tributaries. Though the effects of dams and reservoirs are well-documented, their impacts have been studied individually, with relatively little attention paid to their interaction along a river corridor. We examine the morphological and sedimentological changes in the Upper Missouri River between the Garrison Dam in ND (operational in 1953) and Oahe Dam in SD (operational in 1959). Through historical aerial photography, stream gage data, and cross sectional surveys, we demonstrate that the influence of the upstream dam is still a major control of river dynamics when the backwater effects of the downstream reservoir begin. In the “Anthropocene”, dams are ubiquitous on large rivers and often occur in series, similar to the Garrison Dam Segment. We propose a conceptual model of how interacting dams might affect river geomorphology, resulting in distinct and recognizable morphologic sequences that we term “Inter-Dam sequence” characteristic of major rivers in the US.

  2. Cd and Zn concentrations in small mammals and willow leaves on disposal facilities for dredged material

    NARCIS (Netherlands)

    Mertens, J.; Luyssaert, S.; Verbeeren, S.; Vervaeke, P; Lust, N

    2001-01-01

    Disposal sites for dredged material are often polluted with heavy metals. The uptake of Cd and Zn by small mammals and willow trees was assessed on three sites with a different pollution degree. Detailed soil sampling showed a huge variation in soil characteristics within the sites, typical for

  3. Annual variations in the solar energy conversion efficiency in a willow coppice stand

    International Nuclear Information System (INIS)

    Noronha-Sannervik, A.; Kowalik, P.

    2003-01-01

    Productivity of an experimental willow coppice forest located at Uppsala, Sweden, was monitored between 1985 and 1994. The 2.7 ha stand was planted in 1984 with a density of 20 000 cuttings per ha and was harvested three times. During the monitored period, the annual stem wood production and the cumulated values of total solar radiation during the growing season, were measured. The conversion of incoming solar radiation into stem biomass was evaluated and the results show that the solar energy conversion efficiency (ECE), for the first and fourth year of the cutting cycle, is, on average, 64% of the ECE for the second and third year of the cutting cycle. It is discussed that the low ECE of 1-year-old shoots is related to a delay in leaf canopy development at the beginning of the growing season and lack of weed control after harvest. For the 4-years-old shoots, the low ECE, is believed to be related to the increased shoot and stool mortality caused by the self-thinning process ongoing in the willow stand. It is recommended that the harvesting interval should be based on the specific development of the stand and more attention should be paid to weed control, especially in the first growing season after harvest

  4. Stability of earth dam with a vertical core

    Directory of Open Access Journals (Sweden)

    Orekhov Vyacheslav Valentinovich

    2016-01-01

    Full Text Available Earth dam with impervious element in the form of asphaltic concrete core is currently the most promising type of earth dams (due to simple construction technology and universal service properties of asphaltic concrete and is widely used in the world. However, experience in the construction and operation of high dams (above 160 m is not available, and their work is scarcely explored. In this regard, the paper discusses the results of computational prediction of the stress-strain state and stability of a high earth dam (256 m high with the core. The authors considered asphaltic concrete containing 7 % of bitumen as the material of the core. Gravel was considered as the material of resistant prisms. Design characteristics of the rolled asphaltic concrete and gravel were obtained from the processing of the results of triaxial tests. The calculations were performed using finite element method in elastoplastic formulation and basing on the phased construction of the dam and reservoir filling. The research shows, that the work of embankment dam with vertical core during filling of the reservoir is characterized by horizontal displacement of the lower resistant prism in the tailrace and the formation of a hard wedge prism descending along the core in the upper resistant prism. The key issue of the safety assessment is to determine the safety factor of the overall stability of the dam, for calculation of which the destruction of the earth dam is necessary, which can be done by reducing the strength properties of the dam materials. As a results of the calculations, the destruction of the dam occurs with a decrease in the strength characteristics of the materials of the dam by 2.5 times. The dam stability depends on the stability of the lower resistant prism. The destruction of its slope occurs on the classical circular-cylindrical surface. The presence of a potential collapse surface in the upper resistant prism (on the edges of the descending wedge does

  5. The changing hydrology of a dammed Amazon

    Science.gov (United States)

    Timpe, Kelsie; Kaplan, David

    2017-01-01

    Developing countries around the world are expanding hydropower to meet growing energy demand. In the Brazilian Amazon, >200 dams are planned over the next 30 years, and questions about the impacts of current and future hydropower in this globally important watershed remain unanswered. In this context, we applied a hydrologic indicator method to quantify how existing Amazon dams have altered the natural flow regime and to identify predictors of alteration. The type and magnitude of hydrologic alteration varied widely by dam, but the largest changes were to critical characteristics of the flood pulse. Impacts were largest for low-elevation, large-reservoir dams; however, small dams had enormous impacts relative to electricity production. Finally, the “cumulative” effect of multiple dams was significant but only for some aspects of the flow regime. This analysis is a first step toward the development of environmental flows plans and policies relevant to the Amazon and other megadiverse river basins. PMID:29109972

  6. Isotope technique in JPS dam surveillance: its potential

    International Nuclear Information System (INIS)

    Sabri Hassan

    2006-01-01

    Controlling seepage is one of the most important requirements for safe dams. Any leakage at an earth embankment may be potentially dangerous since rapid internal erosion may quickly enlarge an initially minor defect. Thus dam owners need to have thorough surveillance programs that can forewarn of impending problems from seepage or other factors influencing the safety of dams. In carrying out dam surveillance works, all possible efforts should be considered and foreseeing the potential of isotope technique, JPS (Department of Irrigation and Drainage, Malaysia) and MINT (Malaysian Institute for Nuclear Technology Research) participated actively in the UNDP/RCA/IAEA program under RAS/8/093 project sponsored by the International Atomic Energy Agency (IAEA). Through these activities, it was noted that the technique demonstrated very promising potentials such as in assisting dam site selections, site investigations, watershed studies, dam and reservoir design, leakage investigations and sediments related issues, the two latter ones being relatively critical during the operational life of the dam. Establishment of baseline isotopic characteristics (or fingerprint), hydrochemistry, electrical conductivity and temperature profiles is underway for all JPS dams to be later utilized in diagnosing seepage related issues it is suggested that application of this technique be extended to other dam owners nationwide. (Author)

  7. 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...

  8. 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

  9. The use of short rotation willows and poplars for the recycling of saline waste waters

    Science.gov (United States)

    Jaconette Mirck; Ronald S. Jr. Zalesny; Ioannis Dimitriou; Jill A. Zalesny; Timothy A. Volk; Warren E. Mabee

    2009-01-01

    The production of high-salinity waste waters by landfills and other waste sites causes environmental concerns. This waste water often contains high concentrations of sodium and chloride, which may end up in local ground and surface waters. Vegetation filter systems comprised of willows and poplars can be used for the recycling of saline waste water. These vegetation...

  10. Dry matter losses and quality changes during short rotation coppice willow storage in chip or rod form.

    Science.gov (United States)

    Whittaker, Carly; Yates, Nicola E; Powers, Stephen J; Misselbrook, Tom; Shield, Ian

    2018-05-01

    This study compares dry matter losses and quality changes during the storage of SRC willow as chips and as rods. A wood chip stack consisting of approximately 74 tonnes of fresh biomass, or 31 tonnes dry matter (DM) was built after harvesting in the spring. Three weeks later, four smaller stacks of rods with an average weight of 0.8 tonnes, or 0.4 tonnes DM were built. During the course of the experiment temperature recorders placed in the stacks found that the wood chip pile reached 60 °C within 10 days of construction, but the piles of rods remained mostly at ambient temperatures. Dry matter losses were calculated by using pre-weighed independent samples within the stacks and by weighing the whole stack before and after storage. After 6 months the wood chip stack showed a DM loss of between 19.8 and 22.6%, and mean losses of 23.1% were measured from the 17 independent samples. In comparison, the rod stacks showed an average stack DM loss of between 0 and 9%, and between 1.4% and 10.6% loss from the independent samples. Analysis of the stored material suggests that storing willow in small piles of rods produces a higher quality fuel in terms of lower moisture and ash content; however, it has a higher fine content compared to storage in chip form. Therefore, according to the two storage methods tested here, there may be a compromise between maximising the net dry matter yield from SRC willow and the final fine content of the fuel.

  11. Screening of willow species for resistance to heavy metals: comparison of performance in a hydroponics system and field trials.

    Science.gov (United States)

    Watson, C; Pulford, I D; Riddell-Black, D

    2003-01-01

    The aim of this study was to ascertain whether metal resistance in willow (Salix) clones grown in a hydroponics screening test correlated with data from the same clones grown independently in a field trial. If so, results from a short-term, glasshouse-based system could be extrapolated to the field, allowing rapid identification of willows suitable for planting in metal-contaminated substrates without necessitating longterm field trials. Principal Components Analysis was used to show groups of clones and to assess the relative importance of the parameters measured in both the hydroponics system and the field; including plant response factors such as increase in stem height, as well as metal concentrations in plant tissues. The clones tested fell into two distinct groups. Salix viminalis clones and the basket willow Black Maul (S. triandra) were less resistant to elevated concentrations of heavy metals than a group of hardier clones, including S. burjatica 'Germany,' S.x dasyclados, S. candida and S. spaethii. The more resistant clones produced more biomass in the glasshouse and field, and had higher metal concentrations in the wood. The less resistant clones had greater concentrations of Cu and Ni in the bark, and produced less biomass in the glasshouse and field. Significant relationships were found between the response of the same clones grown the in short-term glasshouse hydroponics system and in the field.

  12. Environmental impacts of small dams on agriculture and ground water development: a case study of Khan pur Dam, Pakistan

    International Nuclear Information System (INIS)

    Ejaz, N.; Shahmim, M.A.; Elahi, A.; Khan, N.M.

    2012-01-01

    The water scarcity issues are increasing through out the world. Pakistan is also facing water crises and its water demands are increasing every day. During this research it is investigated that small dams are playing an important role for the sustainability of groundwater and agriculture. The main objective of this study was to assess the environmental impacts of small dam on agricultural and ground water. Proper planning and management of small dams may improve the sustainable agriculture in Pakistan. It is also concluded that small dams are significantly contributing towards economy, environment, local climate, recreational activities and crop production. Small dams can also be utilized for the production of electricity at local level. On the other hand, water management issues can be resolved by the involvement of local farmer's associations. Water losses through seepage, unlined channels and old irrigation methods are most critical in developing world. Considering the overall positive environmental impacts, construction of small dams must be promoted. (author)

  13. Large dams and risk management

    International Nuclear Information System (INIS)

    Cazelais, N.

    2003-01-01

    In July 1996, Quebec's Saguenay region was subjected to intensive rainfall which caused severe floods and uncontrolled release of several reservoirs, resulting in extensive damage to dam structures and reservoirs. The probability of occurrence for that disaster was 1:10,000. Following the disaster, the Quebec government established a dam management body entitled the Commission scientifique et technique sur la gestion des barrages, which pointed out several safety shortcomings of existing dams. Many were either very old or had undergone significant function change without being subsequently re-evaluated. A report by the Commission stated that damage following the floods could have been limited if the design and operating standards of the dams had been more stringent. A Dam Safety Act was adopted by the Quebec National Assembly on May 30, 2000 following recommendations to retain safer structures. The Act demands regular reporting of operating procedures. Seismic activity was noted as being a topic that requires in-depth examination since Quebec's St. Lawrence Valley, particularly the Charlevoix region, is one of Canada's largest seismic zones. The other is on the west coast in British Columbia. Earthquakes in Quebec are less intense than the ones in British Columbia, but they have higher frequency content which exerts a quasi-resonance wave effect which impacts roads, bridges, buildings and hydroelectric generating facilities. Hydro-Quebec is a public utility which owns 563 retaining structures, of which 228 are ranked as large dams that measure more than 15 metres high, 400 metres long and with a reservoir capacity of more than 1 million cubic metres of water. Hydro-Quebec addresses hydrological, seismic, technological and human risks through a dam safety procedure that includes structured plans for choosing best alternatives through staged exercises. Hazard levels are minimized through the adoption of emergency, prevention and alleviation measures. The utility

  14. 78 FR 62627 - Sam Rayburn Dam Rate

    Science.gov (United States)

    2013-10-22

    ..., Wholesale Rates for Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative, Inc. (Contract No... Schedule SRD-08, Wholesale Rates for Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative... ADMINISTRATION RATE SCHEDULE SRD-13 \\1\\ WHOLESALE RATES FOR HYDRO POWER AND ENERGY SOLD TO SAM RAYBURN DAM...

  15. Evaluatie Dam tot Damloop 2014

    NARCIS (Netherlands)

    Deutekom-Baart de la Faille, Marije

    In het weekend van 20 en 21 september 2014 vond de 30ste editie van de Dam tot Damloop plaats. Onderzoekers van de Hogeschool van Amsterdam en Hogeschool Inholland hebben bij de Dam tot Damloop een evaluatieonderzoek uitgevoerd met als doel het vinden van aanknopingspunten voor het structureel

  16. Willow and poplar for bioenergy on former cropland

    DEFF Research Database (Denmark)

    Georgiadis, Petros

    and water demands of the trees. The water requirements of SRWCs are generally high, and high evapotranspiration rates in both SRC willow and SRF poplar decreased deep percolation, which along with low N concentrations led to low N leaching. Excessive N leaching was only observed when SRC was fertilized......Climate change is one of the 21st century’s greatest challenges and calls for immediate action through the implementation of mitigation strategies. A shift from fossil fuel to renewable energy is a key factor for reducing greenhouse gas emissions to the atmosphere, with bioenergy being...... the predominant sector of renewables in the current European and global energy markets. Dedicated energy crops, such as short rotation woody crops (SRWC), are promising bioenergy feedstock in southern Scandinavia due to their high yields. Such cropping systems have high demands for land, water, and nutrients...

  17. The Total Risk Analysis of Large Dams under Flood Hazards

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2018-02-01

    Full Text Available Dams and reservoirs are useful systems in water conservancy projects; however, they also pose a high-risk potential for large downstream areas. Flood, as the driving force of dam overtopping, is the main cause of dam failure. Dam floods and their risks are of interest to researchers and managers. In hydraulic engineering, there is a growing tendency to evaluate dam flood risk based on statistical and probabilistic methods that are unsuitable for the situations with rare historical data or low flood probability, so a more reasonable dam flood risk analysis method with fewer application restrictions is needed. Therefore, different from previous studies, this study develops a flood risk analysis method for large dams based on the concept of total risk factor (TRF used initially in dam seismic risk analysis. The proposed method is not affected by the adequacy of historical data or the low probability of flood and is capable of analyzing the dam structure influence, the flood vulnerability of the dam site, and downstream risk as well as estimating the TRF of each dam and assigning corresponding risk classes to each dam. Application to large dams in the Dadu River Basin, Southwestern China, demonstrates that the proposed method provides quick risk estimation and comparison, which can help local management officials perform more detailed dam safety evaluations for useful risk management information.

  18. Analysis the dynamic response of earth dam in free vibration and forced by introducing the effect of the interaction dam foundation

    Directory of Open Access Journals (Sweden)

    Malika Boumaiza

    2018-01-01

    Full Text Available The present study concerns the analysis of the dynamic response of earth dam, in free and forced vibration (under the effect of earthquake using the finite element method. The analysis is carried out at the end of dam construction without filling. The behavior of the dam materials and the foundation is linear elastic. In free vibration, to better understand the effect of the dam foundation interaction, we will take into account different site conditions and see their influence on the free vibration characteristics of the dam. In forced vibration, to study the seismic response of the dam, the system is subjected to the acceleration of the Boumerdes earthquake of May 21, 2003 recorded at the station n ° 2 of the dam of Kaddara in the base, with a parametric study taking into account the influence of the main parameters such as the mechanical properties of the soil: rigidity, density.

  19. Ice interactions at a dam face

    Energy Technology Data Exchange (ETDEWEB)

    Morse, B.; Morse, J.; Beaulieu, P.; Pratt, Y. [Laval Univ., Quebec City, PQ (Canada). Dept. of Civil Engineering; Stander, E. [State Univ. of New York, Cobleskill College, Cobleskill, NY (United States). Dept. of Natural Sciences; Cote, A.; Tarras, A.; Noel, P. [Hydro-Quebec, Varennes, PQ (Canada). IREQ

    2009-07-01

    This paper reported on a joint research project between Laval University and Hydro-Quebec to study ice forces on dams in an effort to harmonize design criteria and develop mitigation strategies. This paper introduced the project and explored some of the preliminary results of the 2007-2008 field season. Ice displacement, ice stresses and ice forces on the LaGabelle dam were measured at several locations. The paper identified and discussed the complex relationships between data sets and discussed the spatial-temporal variability of the ice forces and its impact on design criteria. The project objective was to develop design criteria for ice forces on dams and to provide a scientific basis for interpreting and harmonizing existing recommended criteria. The methodology and site description were presented. It was concluded that the ice processes in a reservoir near a dam face subject to water fluctuations are quite complex. Therefore, in order to know the real average pressure on the dam, a significant amount of panels are required, having important implications for determining safe design values. 9 refs., 10 figs.

  20. Thermal effects of dams in the Willamette River basin, Oregon

    Science.gov (United States)

    Rounds, Stewart A.

    2010-01-01

    Methods were developed to assess the effects of dams on streamflow and water temperature in the Willamette River and its major tributaries. These methods were used to estimate the flows and temperatures that would occur at 14 dam sites in the absence of upstream dams, and river models were applied to simulate downstream flows and temperatures under a no-dams scenario. The dams selected for this study include 13 dams built and operated by the U.S. Army Corps of Engineers (USACE) as part of the Willamette Project, and 1 dam on the Clackamas River owned and operated by Portland General Electric (PGE). Streamflows in the absence of upstream dams for 2001-02 were estimated for USACE sites on the basis of measured releases, changes in reservoir storage, a correction for evaporative losses, and an accounting of flow effects from upstream dams. For the PGE dam, no-project streamflows were derived from a previous modeling effort that was part of a dam-relicensing process. Without-dam streamflows were characterized by higher peak flows in winter and spring and much lower flows in late summer, as compared to with-dam measured flows. Without-dam water temperatures were estimated from measured temperatures upstream of the reservoirs (the USACE sites) or derived from no-project model results (the PGE site). When using upstream data to estimate without-dam temperatures at dam sites, a typical downstream warming rate based on historical data and downstream river models was applied over the distance from the measurement point to the dam site, but only for conditions when the temperature data indicated that warming might be expected. Regressions with measured temperatures from nearby or similar sites were used to extend the without-dam temperature estimates to the entire 2001-02 time period. Without-dam temperature estimates were characterized by a more natural seasonal pattern, with a maximum in July or August, in contrast to the measured patterns at many of the tall dam sites

  1. Beaver assisted river valley formation

    Science.gov (United States)

    Westbrook, Cherie J.; Cooper, D.J.; Baker, B.W.

    2011-01-01

    We examined how beaver dams affect key ecosystem processes, including pattern and process of sediment deposition, the composition and spatial pattern of vegetation, and nutrient loading and processing. We provide new evidence for the formation of heterogeneous beaver meadows on riverine system floodplains and terraces where dynamic flows are capable of breaching in-channel beaver dams. Our data show a 1.7-m high beaver dam triggered overbank flooding that drowned vegetation in areas deeply flooded, deposited nutrient-rich sediment in a spatially heterogeneous pattern on the floodplain and terrace, and scoured soils in other areas. The site quickly de-watered following the dam breach by high stream flows, protecting the deposited sediment from future re-mobilization by overbank floods. Bare sediment either exposed by scouring or deposited by the beaver flood was quickly colonized by a spatially heterogeneous plant community, forming a beaver meadow. Many willow and some aspen seedlings established in the more heavily disturbed areas, suggesting the site may succeed to a willow carr plant community suitable for future beaver re-occupation. We expand existing theory beyond the beaver pond to include terraces within valleys. This more fully explains how beavers can help drive the formation of alluvial valleys and their complex vegetation patterns as was first postulated by Ruedemann and Schoonmaker in 1938. ?? 2010 John Wiley & Sons, Ltd.

  2. The Political Ecology of Chinese Large Dams in Cambodia: Implications, Challenges and Lessons Learnt from the Kamchay Dam

    Directory of Open Access Journals (Sweden)

    Giuseppina Siciliano

    2016-09-01

    Full Text Available Given the opportunities offered by foreign investment in energy infrastructure mostly by Chinese firms, the Government of Cambodia is giving high priority to developing hydropower resources for reducing energy poverty and powering economic growth. Using a “Political ecology of the Asian drivers” framework, this paper assesses China’s involvement in the development of large dams’ in Cambodia and its impacts on the access of natural resources such as water and energy by dam builders, local communities and the government. This analysis is based on 61 interviews and 10 focus group discussions with affected communities, institutional actors, Chinese dam builders and financiers in relation to the first large Chinese dam built in Cambodia: the Kamchay dam. Based on the results of the analysis this paper makes recommendations on how to improve the planning, implementation and governance of future large dams in Cambodia.

  3. Ethyl lactate-EDTA composite system enhances the remediation of the cadmium-contaminated soil by Autochthonous Willow (Salix x aureo-pendula CL 'J1011') in the lower reaches of the Yangtze River

    Energy Technology Data Exchange (ETDEWEB)

    Li Jiahua [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Sun Yuanyuan [State Key Laboratory of Pollution Control and Resource Reuse, Department of Hydrosciences, Nanjing University, Nanjing 210093 (China); Yin Ying; Ji Rong [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wu Jichun [State Key Laboratory of Pollution Control and Resource Reuse, Department of Hydrosciences, Nanjing University, Nanjing 210093 (China); Wang Xiaorong [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Guo Hongyan, E-mail: hyguo@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

    2010-09-15

    In order to explore a practical approach to the remediation of the cadmium (Cd)-contaminated soil in the lower reaches of the Yangtze River, we evaluated the effects of a local willow (Salix x aureo-pendula CL 'J1011') of absorbing, accumulating, and translocating Cd; and assessed the potential of chelator ethylenediaminetetraacetic acid (EDTA) in combination with ethyl lactate for enhancing the efficiency of the willow in removing Cd in two water-culture growth chamber trials and a field one. The willow showed a high tolerance to Cd in growth chamber trial 1 where the Cd concentration in the medium reached up to 25 mg L{sup -1} medium, and the bioaccumulation factors (BAFs) of the shoots for Cd rose from 3.8 to 7.4 as the Cd concentration in the medium was elevated from 5 to 25 mg L{sup -1} medium. In growth chamber trial 2, the average Cd removal rates in two treatments with EDTA and ethyl lactate (molar ratios of EDTA to ethyl lactate = 68/39 and 53.5/53.5, respectively) reached 0.71 mg d{sup -1}pot{sup -1} for the duration of Day 5-8 and 0.59 mg d{sup -1}pot{sup -1} for that of Day 8-11, which were 5- and 4-fold of their counterparts in the control, respectively. In the field trial, for the remediational duration of 45 days, three treatments-willow alone, willow combined with EDTA, and willow combined with EDTA and ethyl lactate-led to decreases in the Cd concentration in soil by 5%, 20%, and 29%, respectively; increases in that in the leaves by 14.6%, 56.7%, and 146.5%, respectively; and increases in that in the stems by 15.6%, 41.2%, and 87.4%, respectively, compared to their counterparts on Day 0. These results indicate that EDTA combined with ethyl lactate significantly enhanced the efficiency of willow in removing Cd from the soil. Therefore, a phytoextration system consisting of the autochthonous willow, EDTA, and ethyl lactate has high potential for the remediation of the Cd-polluted soil in the lower reaches of the Yangtze River.

  4. 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...

  5. 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.

  6. Expectations of immortality: dam safety management into the next millennium

    International Nuclear Information System (INIS)

    Palmer, M.D.

    1999-01-01

    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. Sampling procedure in a willow plantation for estimation of moisture content

    DEFF Research Database (Denmark)

    Nielsen, Henrik Kofoed; Lærke, Poul Erik; Liu, Na

    2015-01-01

    Heating value and fuel quality of wood is closely connected to moisture content. In this work the variation of moisture content (MC) of short rotation coppice (SRC) willow shoots is described for five clones during one harvesting season. Subsequently an appropriate sampling procedure minimising...... labour costs and sampling uncertainty is proposed, where the MC of a single stem section with the length of 10–50 cm corresponds to the mean shoot moisture content (MSMC) with a bias of maximum 11 g kg−1. This bias can be reduced by selecting the stem section according to the particular clone...

  8. Langbjorn dam : adaptation for safe discharge of extreme floods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J. [Vattenfall Research and Development, Alvkarleby (Sweden); Ericsson, H.; Gustafsson, A. [SWECO, Stockholm (Sweden); Stenmark, M. [Vattenfall Power Consultant, Ludvika (Sweden); Mikaelsson, J. [Vattenfall Nordic Generation, Bispgarden (Sweden)

    2007-07-01

    The Langbjorn hydropower scheme, composed of an embankment dam with an impervious core of compacted moraine, a spillway section and a powerhouse, is located on the Angermanalven River in north Sweden. The scheme was commissioned in 1959 and is owned by Vattenfall. As part of its dam safety program, Vattenfall plans to adapt and refurbish many of its dams to the updated design-flood and dam-safety guidelines. Langbjorn is classified as a high hazard dam, as its updated design flood is 30 per cent higher than the existing spillway capacity. Safety evaluations were conducted for the Langbjorn dam, and, as required by the higher safety standard, there was a need to rebuild the dam, so that the design flood could be safely released without causing failure of the dam. This paper provided information on the Langbjorn hydropower scheme and discussed the planned rebuilding measures. For example, the design flood was accommodated by allowing a temporary raise of the water level by 1.3 metres above the legal retention reservoir level, which required heightening and reinforcement of the dam. Specifically, the paper discussed measures to increase the discharge capacity; handling and control of floating debris; improvement and heightening of impervious core in left and right connecting dam and abutment; measures to increase the stability of the left steep riverbank; and measures to increase stability of the spillway monoliths and the left guide wall. In addition, the paper discussed measures to ensure stability of the downstream stretch of the river bank and increase instrumentation. The paper also presented the results of hydraulic investigations to investigate the risk of erosion downstream of the dam. It was concluded that the dam could discharge the design flood and that the stability of the dam was improved and judged to be satisfactory during all foreseeable conditions. 2 refs., 8 figs.

  9. The mathematics of dam safety

    Energy Technology Data Exchange (ETDEWEB)

    Widmann, R. [Osterreichische Gesellschaft fuer Geomechanik, Salzburg (Austria)

    1997-05-01

    The safety of a dam is determined by its design, construction and supervision during operation. High arch dam failures have dropped dramatically since the early part of this century. An essential part of the success story relates to improved measurement techniques that can detect earlier unexpected behaviour that may lead to failure. (UK)

  10. Automatic dam concrete placing system; Dam concrete dasetsu sagyo no jidoka system

    Energy Technology Data Exchange (ETDEWEB)

    Yoneda, Y; Hori, Y; Nakayama, T; Yoshihara, K; Hironaka, T [Okumura Corp., Osaka (Japan)

    1994-11-15

    An automatic concrete placing system was developed for concrete dam construction. This system consists of the following five subsystems: a wireless data transmission system, an automatic dam concrete mixing system, a consistency determination system, an automatic dam concrete loading and transporting system, and a remote concrete bucket opening and closing system. The system includes the following features: mixing amount by mixing ratio and mixing intervals can be instructed from a concrete placing site by using a wireless handy terminal; concrete is mixed automatically in a batcher plant; a transfer car is started, and concrete is charged into a bucket automatically; the mixed concrete is determined of its properties automatically; labor cost can be reduced, the work efficiency improved, and the safety enhanced; and the system introduction has resulted in unattended operation from the aggregate draw-out to a bunker line, manpower saving of five persons, and reduction in cycle time by 10%. 11 figs., 2 tabs.

  11. Dam safety investigations of the concrete structures of Hugh Keenleyside dam

    International Nuclear Information System (INIS)

    Hanna, A.W.; Nunn, J.O.H.; Cornish, L.; Northcott, P.

    1993-01-01

    The Hugh Keenleyside dam is located on the Columbia River in southeastern British Columbia, and impounds Arrow Lakes Reservoir which has a live storage of 8.8 km 3 and drains an area of 36,000 km 2 . It consists of a number of concrete structures, with a total length of 360 m and a maximum height of 58 m, and an earthfill embankment which spans across the original river channel. The 450 m long zoned earthfill dam is founded on pervious alluvium over 150 m deep. It has a sloping impervious core constructed from glacial till which extends 670 m upstream of the dam. This impervious blanket extends over the full width of the reservoir and is connected to the upstream face of the concrete structures. The results of a dam safety study, which was carried out due to the presence of high uplift pressures at some parts of the foundation, and stability concerns, are presented. The investigation concluded that the high uplift pressures were due to a localized defect in the upstream blanket and did not indicate any general deterioration of the blanket. Techniques that were found to be of particular use in the study for defining the source and nature of the foundation defects were: temperature surveys of flows from piezometers, cells and drains; air injection tests; and pressure response testing of cells, piezometers and drains to establish foundation interconnections. The concrete structures met the stability criteria for all load cases considered except for the navigation lock and the low level outlets. 3 refs., 6 figs

  12. The effects of first-year shoot cut back on willow biomass production during the first and second cutting cycle; Effekter av skottnedklippning efter etableringsaaret paa produktionen under foersta och andra omdrevet i salixodlingar

    Energy Technology Data Exchange (ETDEWEB)

    Verwijst, Theo; Nordh, Nils-Erik

    2010-05-15

    During the early phase of commercialisation of willow short rotation forestry in Sweden it was considered to be important to cut down the shoots after the establishment year, and this practice still is maintained today. Several reasons then were put forward for cutting down. The primary goal was to stimulate sprouting of more shoots, thereby obtaining a rapidly closing stand which could compete with weeds. Another reason was that it would enable weed control during the second year. In some of the older clones, which exhibited bow-shaped shoots, cutting down was supposed to lead to more straight growing shoots which rendered less biomass loss at harvest. In the meantime, the practice of cutting down has been abandoned in Denmark, and there are reasons to scrutinise the effects of cutting down on available biomass production figures from Swedish field trials. The main goal with this project was to try to quantify the effects of cutting down on the biomass productivity of willow during the first and later cutting cycles. Thus far, efforts in this research topic have not led to a scientifically documented quantification on the effects, and therefore a scientific basis for hands-on recommendations to willow growers is lacking. The purpose of our work consequently was to generate practical recommendations with regard to the management measure of cutting down, and the audience targeted consisted of willow growers (farmers, land-owners and entrepreneurs) who are deciding about and perform the actual management of willow stands to obtain higher yields. This information also is of large relevance for all extension workers in willow growing. Data have been collected from a field trial which was planted in Flosta, Enkoeping, in 2005. As this was the only experiment on cutting down which ran during the project period, we searched the archives which contained material from another experiment which ran from 1992 to 1996 in Ultuna, Uppsala, and from which some date were collected

  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. On the response of large dams to incoherent seismic excitation

    International Nuclear Information System (INIS)

    Ramadan, O.; Novak, M.

    1993-01-01

    An intensive parametric study was conducted to investigate the response of concrete gravity dams to horizontal, spatially variable seismic ground motions. Both segmented dams consisting of separate blocks, or monoliths, and continuous monolithic dams are considered. The study includes the effects of various parameters on system natural frequencies, vibration modes, modal displacement ratios, as well as dam displacements and internal stresses due to spatially variable ground motions. The dam analytical model, and dam response to incoherent ground motions are described. The results show that the dam vibrates almost as a rigid body under the fully correlated waves, but bends and twists significantly under the spatially correlated motions. Dam-foundation interaction magnifies the low frequency components of the dam response, more so for a full reservoir, but decreases the high frequency components. For long dams, the effects of spatially incoherent ground motions are qualitatively different and can be much greater than those due to surface travelling waves. 3 refs., 3 figs

  15. the effect of age of dam on weaning mass for ftve dam breed types

    African Journals Online (AJOL)

    SUMMARY: The effect of age of dam on adjusted 210 day calf weaning mass was estimated by the Least Squares method for 5 dam types on 2 farms. ... the later maturing breeds would have a low level of productivity because these cows would be eliminated in their potentially prime .... time at 28 (2A) or 3l (28) months old.

  16. Microbial expression profiles in the rhizosphere of willows depend on soil contamination

    Science.gov (United States)

    Yergeau, Etienne; Sanschagrin, Sylvie; Maynard, Christine; St-Arnaud, Marc; Greer, Charles W

    2014-01-01

    The goal of phytoremediation is to use plants to immobilize, extract or degrade organic and inorganic pollutants. In the case of organic contaminants, plants essentially act indirectly through the stimulation of rhizosphere microorganisms. A detailed understanding of the effect plants have on the activities of rhizosphere microorganisms could help optimize phytoremediation systems and enhance their use. In this study, willows were planted in contaminated and non-contaminated soils in a greenhouse, and the active microbial communities and the expression of functional genes in the rhizosphere and bulk soil were compared. Ion Torrent sequencing of 16S rRNA and Illumina sequencing of mRNA were performed. Genes related to carbon and amino-acid uptake and utilization were upregulated in the willow rhizosphere, providing indirect evidence of the compositional content of the root exudates. Related to this increased nutrient input, several microbial taxa showed a significant increase in activity in the rhizosphere. The extent of the rhizosphere stimulation varied markedly with soil contamination levels. The combined selective pressure of contaminants and rhizosphere resulted in higher expression of genes related to competition (antibiotic resistance and biofilm formation) in the contaminated rhizosphere. Genes related to hydrocarbon degradation were generally more expressed in contaminated soils, but the exact complement of genes induced was different for bulk and rhizosphere soils. Together, these results provide an unprecedented view of microbial gene expression in the plant rhizosphere during phytoremediation. PMID:24067257

  17. Proceeding of the public safety around dams conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The Canadian Dam Association hosted the Public Safety Around Dams workshop in which presentations were given in the morning to describe the different measures and methods implemented by the Ontario Ministry of Natural Resources, Ontario Power Generation and others to improve safety around dams. In the afternoon, the participants toured the Auburn and Lakefield dams and facilities to view the infrastructures and equipment. A roundtable discussion concluded the day. Following this workshop, a Public Safety Around Dams group was created on the social network site, LinkedIn. This conference featured 6 presentations, 3 of which have been catalogued separately for inclusion in this database.

  18. Enzymatic Saccharification of Shrub Willow Genotypes with Differing Biomass Composition for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Michelle J. Serapiglia

    2013-03-01

    Full Text Available In the conversion of woody biomass feedstocks into liquid fuel ethanol, the pretreatment process is the most critical and costly step. Variations in biomass composition based on genetic differences or environmental effects have a significant impact on the degree of accessibility accomplished by pretreatment and subsequent sugar release by enzymatic hydrolysis. To evaluate this, biomass from 10 genetically diverse, genotypes of shrub willow (Salix spp. was pretreated with a hot-water process at two levels of severity, hydrolyzed using a combination of two commercial enzyme cocktails, and the release of hexose and pentose monomers was quantified by HPLC. Among the genotypes selected for analysis, cellulose content ranged from 39 to 45% (w/w and lignin content ranged from 20 to 23% (w/w at harvest. Differences in the effectiveness of the pretreatment process were observed among the various willow genotypes. Correlations were identified between total sugar release and % cellulose and % lignin content. There was a significant effect of pretreatment severity on polysaccharide accessibility, but the response to pretreatments was different among the genotypes. At the high severity pretreatment ‘SV1’ was the least recalcitrant with sugar release representing as much as 60% of total biomass. These results suggest that structural, as well as chemical characteristics of the biomass may influence pretreatment and hydrolytic efficiency.

  19. Geodetic deformation monitoring at Pendidikan Diponegoro Dam

    Science.gov (United States)

    Yuwono, Bambang Darmo; Awaluddin, Moehammad; Yusuf, M. A.; Fadillah, Rizki

    2017-07-01

    Deformation monitoring is one indicator to assess the feasibility of Dam. In order to get the correct result of the deformation, it is necessary to determine appropriate deformation monitoring network and the observation data should be analyse and evaluated carefully. Measurement and analysis of deformation requires relatively accurate data and the precision is high enough, one of the observation method that used is GPS (Global Positioning System). The research was conducted at Pendidikan Undip Dams is Dam which is located in Tembang. Diponegoro Dam was built in 2013 and a volume of 50.86 m3 of water, inundation normal width of up to 13,500 m2. The main purpose of these building is not only for drainage but also for education and micro hydro power plant etc. The main goal of this reasearch was to monitor and analyze the deformation at Pendidikan Undip Dam and to determaine whether GPS measurement could meet accuracy requirement for dam deformation measurements. Measurements were made 2 times over 2 years, 2015 and 2016 using dual frequency GPS receivers with static methods and processed by Scientific Software GAMIT 10.6

  20. Fiber length and pulping characteristics of switchgrass, alfalfa stems, hybrid poplar and willow biomasses.

    Science.gov (United States)

    Ai, Jun; Tschirner, Ulrike

    2010-01-01

    Switchgrass (Panicum virgatum), alfalfa stems (Medicago sativa), second year growth hybrid poplar (Populus) and willow (Salix spp.) were examined to determine fiber characteristics, pulping behavior and paper properties. Alfalfa stems and switchgrass both showed length weighted average fiber length (LWW) of 0.78 mm, a very narrow fiber length distribution and high fines content. Willow and hybrid poplar have lower fines content but a very low average fiber length (0.42 and 0.48 mm LWW). In addition, the four biomass species showed distinctly different chemical compositions. Switchgrass was defibered successfully using Soda and Soda Anthraquinone (AQ) pulping and demonstrated good paper properties. Both fast-growing wood species pulped well using the Kraft process, and showed acceptable tensile strength, but low tear strength. Alfalfa stems reacted very poorly to Soda and Soda AQ pulping but responded well to Kraft and Kraft AQ. Pulps with tensile and tear strength considerably higher than those found for commercial aspen pulps were observed for alfalfa. All four biomass species examined demonstrated low pulp yield. The highest yields were obtained with poplar and switchgrass (around 43%). Considering the short fibers and low yields, all four biomass types will likely only be used in paper manufacturing if they offer considerable economic advantage over traditional pulp wood.

  1. Investigating leaks in dams and reservoirs

    International Nuclear Information System (INIS)

    2003-01-01

    Millions of people throughout the world depend on dams and reservoirs for electricity, water and flood protection. Dams require significant investment to build and maintain, and yet their usefulness and integrity are constantly threatened by leakage and sedimentation. Isotope hydrology techniques, combined with conventional analytical methods, are a cost-effective tool to reduce such threats. The International Atomic Energy Agency is promoting their use to protect these investments and improve management, particularly by supporting specialized teams of scientists and engineers to investigate dam leakage in African countries on request. (IAEA)

  2. A study on the effect of a broken large sabo dam on the sediment transportation in channel - an example of Baling-sabo-dam

    Science.gov (United States)

    Tseng, W. H.; Shieh, C. L.; Lee, S. P.; Tsang, Y. C.

    2009-04-01

    To retard the sediment transportation and its effect on the reservoir, large sabo dams are built in the main channel of the reservoir watershed in Taiwan. Therefore, these large sabo dams affect upstream, downstream, and the reservoir significantly if the dam breaks. There was about 450 mm of rain fell in the reservoir watershed during typhoon Wipha that struck Taiwan on 17-19, September, 2007. This heavy rainfall caused the Baling-sabo-dam broken about 60 m of the upper Dahan Creek in the Shimen Reservoir watershed. The dam, built in 1977, is 38 m in height, 80 m in width, and is designed to reserve sediment materials about 10 million m3. The upper river bed was diminished maximum to 20 m in a month; the deposited and affected areas are unable to estimate and still required to be observed. The main purpose of this paper is to analyze the topographic characteristic of the channel after the dam broke according to the topographic and surveyed data before and after the dam broke. The longitudinal profile and the cross section data show the effects to the channel after the dam break and the channel is able to classify in several sections. A simple comparison of the sediment discharge estimated from the hydrologic data with the topographic survey data is also analyzed. Keywords:dam break, sabo dam, sediment discharge

  3. Combustion quality of poplar and willow clones grown as SRC at four sites in Brandenburg, Germany

    DEFF Research Database (Denmark)

    Liu, Na; Ugilt Larsen, Søren; Jørgensen, Uffe

    2017-01-01

    The fuel quality was assessed for nine poplar clones (AF2, Androscoggin, Max1, Max3, Max4, Monviso, Muhle-Larsen, NE42, Weser6) and one willow clone (Inger) grown as short rotation coppice (SRC) on four sites in the Brandenburg area in Germany. Fuel quality was analysed in 3-year old shoots in te...

  4. The Grand Ethiopian Renaissance Dam and Ethiopia's Succession ...

    African Journals Online (AJOL)

    Tadesse Kassa Woldetsadik

    2013-06-01

    Jun 1, 2013 ... Dam concessions engendered detrimental impacts on Ethiopia's riparian rights ... control works on the Aswan High and the Roseires dams. Disturbed by the ... hegemonic control that would inevitably ensue from construction of the Dam ...... Projects Implementation Division AAAID, Sudan, p.1. 39 Ibid.

  5. Dam failure analysis/calibration using NWS models on dam failure in Alton, New Hampshire

    International Nuclear Information System (INIS)

    Capone, E.J.

    1998-01-01

    The State of New Hampshire Water Resources Board, the United States Geological Service, and private concerns have compiled data on the cause of a catastrophic failure of the Bergeron Dam in Alton, New Hampshire in March of 1996. Data collected related to the cause of the breach, the breach parameters, the soil characteristics of the failed section, and the limits of downstream flooding. Dam break modeling software was used to calibrate and verify the simulated flood-wave caused by the Bergeron Dam breach. Several scenarios were modeled, using different degrees of detail concerning the topography/channel-geometry of the affected areas. A sensitivity analysis of the important output parameters was completed. The relative importance of model parameters on the results was assessed against the background of observed historical events

  6. STABILITAS CHECK DAM DI ARBORETUM DESA SUMBER BRANTAS

    Directory of Open Access Journals (Sweden)

    Endang Purwati

    2012-09-01

    Full Text Available Abstract: The stability of check-dam in arboretum of Sumber Brantas village. Sumber Brantas water sources area is arboretum territory which has to be maintained as conservation either for technical or vegetation (plants cover by sustainable development. Arboretum territory is made as asylum in irrigation system district of Brantas River. This research discusses technical conservation activity to build the check dam in conserving the area. Check dam is built dimensionally by using HEC-RAS Program to get safe and stable dimension for rolling, shifting and piping of Sf > 1.5, and based on hydrologic analysis to get maximum flood discharge of 48.01 m3second-1. Hydraulic analysis is used to get water level profile and pressure for the dam body. Stability of the structure will be controlled by construction load (weight of check dam and its fully sediment storage condition. The result of this research shows that the safe and stable dimension for check dam are as follows: 28 meter of width; 3 meter of main height; 1.5 meter of sub-height; 10 meter of stilling basin length (Main Dam–Sub Dam.

  7. Jackson Mills and Mine Falls Dams, Nashua, New Hampshire. Reconnaissance Report, Hydroelectric Feasibility. Volume 1, Jackson Mills Dam.

    Science.gov (United States)

    1979-12-01

    Catalpa Solidago sp. Goldenrod Aster novae - angliae New England Aster Acer saccharum Sugar Maple Ulmus rubra Slippery elm Solanum hi rum Common...red pine, and hemlock are the common softwood species, and the common hardwood species include red maple, silver maple, white oak, willow, slippery ... elm and birch. In 1972, between 70 and 7S percent of the total area of the watershed consisted of forests and primarily wooded land. (Reference 3

  8. The blind men meet the elephant at the dam: Alternative spatial and taxonomic components reveal different insights about how low-head dams impact fish biodiversity

    Science.gov (United States)

    Fencl, Jane S.; Mather, Martha E.; Smith, Joseph M.; Hitchman, Sean M.

    2017-01-01

    Dams are ubiquitous environmental impacts that threaten aquatic ecosystems. The ability to compare across research studies is essential to conserve the native biodiversity that is impacted by the millions of low‐head dams that currently fragment streams and rivers. Here, we identify a previously unaddressed obstacle that impedes this generalization. Specifically, divergent spatial and taxonomic approaches that result from different conceptualizations of the dam‐biodiversity problem can produce conflicting science‐based conclusions about the same dam impact. In this research, using the same dammed and undammed sites, we evaluated the scientific generality of different conceptualizations of the dam‐biodiversity problem. We compared two different but commonly used spatial approaches—(1) above dam–below dam vs. (2) undammed–dammed comparisons—and 11 different, commonly used taxonomic approaches (three assemblage summaries, eight guilds). Sites above the dam structure had less diverse fish assemblages than sites below dams, whereas sites below the dam structure were similar to undammed sites. Thus, spatial approach 1 detected a large dam effect and spatial approach 2 detected a small dam effect. Similarly, some taxonomic responses (species richness, diversity, abundance, and number of guilds) detected large dam effects; other responses detected small (riffle specialist guild) or no dam effects (pool generalists). In summary, our results showed that how the problem was framed altered scientific conclusions and created different dam realities. The metaphor of how individual blind men disagree about the structure of an elephant, based on examinations of different body parts, reinforces the need for a coordinated, holistic perspective on dam research. Although no single approach is adequate for all problems, identifying the form, consequences of, and relationships among different research conceptualizations will set the stage for future syntheses of dam

  9. Coupling legacy geomorphic surface facies to riparian vegetation: Assessing red cedar invasion along the Missouri River downstream of Gavins Point dam, South Dakota

    Science.gov (United States)

    Greene, Samantha L.; Knox, James C.

    2014-01-01

    Floods increase fluvial complexity by eroding established surfaces and creating new alluvial surfaces. As dams regulate channel flow, fluvial complexity often decreases and the hydro-eco-geomorphology of the riparian habitat changes. Along the Missouri River, flow regulation resulted in channel incision of 1-3 m within the study area and disconnected the pre-dam floodplain from the channel. Evidence of fluvial complexity along the pre-dam Missouri River floodplain can be observed through the diverse depositional environments represented by areas of varying soil texture. This study evaluates the role of flow regulation and depositional environment along the Missouri River in the riparian invasion of red cedar downstream of Gavins Point dam, the final dam on the Missouri River. We determine whether invasion began before or after flow regulation, determine patterns of invasion using Bayesian t-tests, and construct a Bayesian multivariate linear model of invaded surfaces. We surveyed 59 plots from 14 riparian cottonwood stands for tree age, plot composition, plot stem density, and soil texture. Red cedars existed along the floodplain prior to regulation, but at a much lower density than today. We found 2 out of 565 red cedars established prior to regulation. Our interpretation of depositional environments shows that the coarser, sandy soils reflect higher energy depositional pre-dam surfaces that were geomorphically active islands and point bars prior to flow regulation and channel incision. The finer, clayey soils represent lower energy depositional pre-dam surfaces, such as swales or oxbow depressions. When determining patterns of invasion for use in a predictive statistical model, we found that red cedar primarily establishes on the higher energy depositional pre-dam surfaces. In addition, as cottonwood age and density decrease, red cedar density tends to increase. Our findings indicate that flow regulation caused hydrogeomorphic changes within the study area that

  10. Seismic response of uplifting concrete gravity dams

    International Nuclear Information System (INIS)

    Leger, P.; Sauve, G.; Bhattacharjee, S.

    1992-01-01

    The foundation interaction effects on the seismic response of dam-foundation systems have generally been studied using the linear elastic finite element models. In reality, the foundation can not develop effective tensile stresses to a significant degree along the interface. A two-dimensional finite element model, in which nonlinear gap elements are used at the dam-foundation interface to determine the uplift response of concrete gravity dams subjected to seismic loads, is presented. Time domain analyses were performed for a wide range of modelling assumptions such as dam height, interface uplift pressure, interface mesh density, and earthquake input motions, that were systematically varied to find their influence on the seismic response. The nonlinear interface behavior generally reduces the seismic response of dam-foundation systems acting as a seismic isolation mechanism, and may increase the safety against sliding by reducing the base shear transmitted to the foundation. 4 refs., 5 figs., 6 tabs

  11. Distribution and abundance of Least Bell’s Vireos (Vireo bellii pusillus) and Southwestern Willow Flycatchers (Empidonax traillii extimus) on the Middle San Luis Rey River, San Diego County, southern California—2017 data summary

    Science.gov (United States)

    Allen, Lisa D.; Howell, Scarlett L.; Kus, Barbara E.

    2018-04-20

    We surveyed for Least Bell’s Vireos (LBVI) (Vireo bellii pusillus) and Southwestern Willow Flycatchers (SWFL) (Empidonax traillii extimus) along the San Luis Rey River, between College Boulevard in Oceanside and Interstate 15 in Fallbrook, California (middle San Luis Rey River), in 2017. Surveys were conducted from April 13 to July 11 (LBVI) and from May 16 to July 28 (SWFL). We found 146 LBVI territories, at least 107 of which were occupied by pairs. Five additional transient LBVIs were detected. LBVIs used five different habitat types in the survey area: mixed willow, willow-cottonwood, willow-sycamore, riparian scrub, and upland scrub. Forty-four percent of the LBVIs occurred in habitat characterized as mixed willow and 89 percent of the LBVI territories occurred in areas with greater than 50 percent native plant cover. Of 16 banded LBVIs detected in the survey area, 8 had been given full color-band combinations prior to 2017. Four other LBVIs with single (natal) federal bands were recaptured and banded in 2017. Three LBVIs with single dark blue federal bands indicating that they were banded as nestlings on the lower San Luis Rey River and one LBVI with a single gold federal band indicating that it was banded as a nestling on Marine Corps Base Camp Pendleton (MCBCP) could not be recaptured for identification. One banded LBVI emigrated from the middle San Luis Rey River to the lower San Luis Rey River in 2017.One resident SWFL territory and one transient Willow Flycatcher of unknown subspecies (WIFL) were observed in the survey area in 2017. The resident SWFL territory, which was comprised of mixed willow habitat (5–50 percent native plant cover), was occupied by a single male from May 22 to June 21, 2017. No evidence of pairing or nesting activity was observed. The SWFL male was banded with a full color-combination indicating that he was originally banded as a nestling on the middle San Luis Rey River in 2014 and successfully bred in the survey area in 2016

  12. Seismic performance assessment of latyan concrete buttress dam ...

    African Journals Online (AJOL)

    In order to design earthquake resistant dams and evaluate the safety of existing dams that will be exposed to future earthquakes, it is essential to have accurate and reliable analysis procedures to predict the stresses and deformations in dams subjected to earthquake ground motion. For a damwater- foundation system, the ...

  13. Walden North Dam overtopping : emergency response and rehabilitation

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, S. [FortisBC Inc., South Slocan, BC (Canada); McCreanor, J. [Acres International Ltd., Calgary, AB (Canada); Cronin, D.L.R.; Daw, D. [Acres International Ltd., Vancouver, BC (Canada)

    2004-09-01

    This paper described the events that led to the overtopping of the Walden North Dam during a heavy rainfall in June 2002, resulting in a breach around an abutment wall. The dam is part of a run-of-river hydro development on Cayoosh Creek near Lillooet, British Columbia. The Walden North Dam was a low, 46 meter wide concrete dam with a single radial gate. The dam overtopping was attributed to failure of the radial gate hoist. Prior to this event, the dam had been classified by the British Columbia Dam Safety Authorities as a high and then a low consequence category of failure. As facility managers, Aquila Networks Canada Ltd. established an immediate action plan to stabilize the situation and resume normal power production by applying the following priorities: (1) ensure safety of workers and the public, (2) limit further damage to the dam and other facilities, (3) ensure environmental protection, and (4) continue to operate the generation units. Local authorities were informed to evacuate a downstream campsite and environmental agencies were contacted along with safety regulators. Repairs included demolition of the damaged portion of the structure and construction a new two-bay gate/stoplog spillway and bridge. Construction was completed by September 2003 according to the requirements of the Department of Fisheries and Oceans for minimum flow, accurate control of fish flows and environmental monitoring of the stream area. 10 figs.

  14. Synthesis of carbon nanospheres using fallen willow leaves and adsorption of Rhodamine B and heavy metals by them.

    Science.gov (United States)

    Qu, Jiao; Zhang, Qian; Xia, Yunsheng; Cong, Qiao; Luo, Chunqiu

    2015-01-01

    This paper focuses on the synthesis of carbon nanospheres (CNSs) using fallen willow leaves as a low-cost precursor. The scanning electron microscopy (SEM) image and transmission electron microscopy (TEM) image demonstrated that the structure of synthesized CNSs was spherical, with a diameter of 100 nm. The crystal structure and chemical information were characterized by Raman spectrum and energy-dispersive spectrum (EDS), respectively. BET results showed that the CNSs had a larger specific surface area of 294.32 m(2) g(-1), which makes it a potentially superior adsorbent. Rh-B and heavy metal ions such as Cu(2+), Zn(2+), and Cr(6+) were used as targets to investigate the adsorption capacity of the CNSs. The effects of adsorption parameters such as adsorption equilibrium time, dose of CNSs, adsorption kinetics, and effect factors were also studied. These findings not only established a cost-effective method of synthesizing CNSs using fallen willow leaves but also broadened the potential application range of these CNSs.

  15. On the irrigation requirements of cottonwood (Populus fremontii and Populus deltoides var. wislizenii) and willow (Salix gooddingii) grown in a desert environment

    Science.gov (United States)

    Hartwell, S.; Morino, K.; Nagler, P.L.; Glenn, E.P.

    2010-01-01

    Native tree plots have been established in river irrigation districts in the western U.S. to provide habitat for threatened and endangered birds. Information is needed on the effective irrigation requirements of the target species. Cottonwood (Populus spp.) and willow (Salix gooddingii) trees were grown for seven years in an outdoor plot in a desert environment in Tucson, Arizona. Plants were allowed to achieve a nearly complete canopy cover over the first four years, then were subjected to three daily summer irrigation schedules of 6.20??mm??d-1; 8.26??mm??d-1 and 15.7??mm??d-1. The lowest irrigation rate was sufficient to maintain growth and high leaf area index for cottonwoods over three years, while willows suffered considerable die-back on this rate in years six and seven. These irrigation rates were applied April 15-September 15, but only 0.88??mm??d-1 was applied during the dormant period of the year. Expressed as a fraction of reference crop evapotranspiration (ETo), recommended annual water applications plus precipitation (and including some deep drainage) were 0.83 ETo for cottonwood and 1.01 ETo for willow. Current practices tend to over-irrigate restoration plots, and this study can provide guidelines for more efficient water use. ?? 2010 Elsevier Ltd.

  16. Developing an integrated dam safety program

    International Nuclear Information System (INIS)

    Nielsen, N. M.; Lampa, J.

    1996-01-01

    An effort has been made to demonstrate that dam safety is an integral part of asset management which, when properly done, ensures that all objectives relating to safety and compliance, profitability, stakeholders' expectations and customer satisfaction, are achieved. The means to achieving this integration of the dam safety program and the level of effort required for each core function have been identified using the risk management approach to pinpoint vulnerabilities, and subsequently to focus priorities. The process is considered appropriate for any combination of numbers, sizes and uses of dams, and is designed to prevent exposure to unacceptable risks. 5 refs., 1 tab

  17. Thermal monitoring of leakage through Karkheh embankment dam, Iran

    Energy Technology Data Exchange (ETDEWEB)

    Mirghasemi, A.A.; Bagheri, S.M. [Tehran Univ., Tehran (Iran, Islamic Republic of). Dept. of Civil Engineering; Heidarzadeh, M. [Tehran Univ., Tehran (Iran, Islamic Republic of). Dept. of Civil Engineering]|[Mahab Ghodss Consulting Engineers, Tehran (Iran, Islamic Republic of)

    2007-07-01

    A newly developed and simple method for monitoring seepage in embankment dams was presented. The method of temperature measurement is based on the fact that a change in permeability results in a change in seepage flow, thereby causing a temperature change that can be readily measured in the dam body and foundation. In this study, water leaking through the Karkheh embankment dam was thermally analyzed to determine a pattern and amount of water seepage. With nearly 33 million cubic metres of fill, the Karkheh earth and rock-fill dam is the largest dam in Iran. Construction was completed in 2000. The thermal processes in the embankment were studied due to the dam's complex thermo-hydraulic behaviour. Thermal data was collected and analyzed during construction and operation of the dam. This paper presented the temperature variations for the different dam zones, including core, upstream shell, downstream shell, upstream filter, downstream filter and the plastic concrete cut-off wall. It was determined that the clay core works very well as an impermeable curtain. It was also shown that temperature variations of the Karkheh reservoir water is seasonal, and decrease as water depth increases. The reservoir water temperature remains constant beyond depths of 60 metres. The thermal behaviour of the core is not similar to that of the reservoir, indicating a very low value of seepage through the core. The pattern of temperature variations in the upstream shell in the left abutment is harmonic, while in the right abutment it is not harmonic. A harmonic pattern of temperature variation exists in some aquifers of the dam foundation, indicating high seepage through these aquifers. The Karkheh dam cut-off wall performs satisfactorily. It was determined that one dimensional equations for estimating seepage cannot be applied for the Karkheh dam. 17 refs., 11 figs.

  18. Grouting Applications in Cindere Dam

    Directory of Open Access Journals (Sweden)

    Devrim ALKAYA

    2011-01-01

    Full Text Available Grouting is one of the most popular method to control the water leakage in fill dam constructions. With this regard this method is widely used in all the world. Geological and geotechnical properties of rock are important parameters affect the design of grouting. In this study, geotechnical properties of Cindere Dam's base rock and the grouting prosedure have been investigated with grouting pressure.

  19. Effect of Nearshore Islands on Tsunami Inundation in Shadow Zones

    Science.gov (United States)

    Goertz, J.; Kaihatu, J. M.; Kalligeris, N.; Lynett, P. J.; Synolakis, C.

    2017-12-01

    Field surveys performed in the wake of the 2010 Mentawai tsunami event have described the belief of local residents that offshore islands serve as possible tsunami sheltering mechanisms, reducing the corresponding inundation on beaches behind the islands, despite the fact that deduced inundation from debris lines show this to be in fact untrue (Hill et al. 2012). Recent numerical model studies (Stefanakis et al. 2014) have shown that inundation levels on beaches behind conical islands are indeed higher than they are on open coastlines. While work has been done on tsunami amplification on the lee side of islands (Briggs et al. 1995), no work has been done concerning tsunami inundation on beach areas behind the islands. A series of experiments to address this were conducted in the Directional Wave Basin (DWB) at the O.H. Hinsdale Wave Research Laboratory at Oregon State University in summer 2016. A series of four sheet metal islands (two with a full conical section, two truncated at the water line) were placed at varying distances from the toe of a 1/10 sloping beach. Incident wave conditions consisting of solitary waves and full-stroke "dam break" waves were run over the islands. Free surface elevations, velocities, and beach runup were measured, with the intent of determining relationships between the wave condition, the island geometry and distance from the beach, and the tsunami characteristics. A series of runup measurements from a particular set of experiments can be seen in Figure 1. Based on these preliminary analyses, it was determined that: A) inundation was always amplified behind the island relative to areas outside this shadow zone; and B) inundation was generally highest with the island closest to the beach, except in the case where the tsunami wave broke prior to reaching the island. In this latter scenario, the inundation behind the island increased with island distance from the beach. The development of relationships between the inundation levels

  20. El Alzado de la Vivienda en Willow Road Ernö Goldfinger

    Directory of Open Access Journals (Sweden)

    Ignacio Román Santiago

    2015-05-01

    Full Text Available ResumenEl artículo propone aproximarse a la vivienda que el arquitecto húngaro Ernö Goldfinger construyó para sí mismo en 1939 en el barrio de Hampstead (Londres. El complejo y singular ejercicio en el que Goldfinger apoya gran parte de sus teorías se manifiesta en esta propuesta para Willow Road y se desvela especialmente en su fachada. Para el arquitecto es fundamental estudiar la experiencia humana del espacio arquitectónico relacionada con la envolvente del edificio y, en este sentido, sulegado teórico se expresa en los textos que escribió para la revista Architectural Review entre los años 1941 y 1942: The Sensation of Space, Urbanism and Spatial Order y Elements of Enclosed Space.Analizar este alzado enigmático provoca algunos interrogantes que son, en sí mismos, un auténtico manifi esto a favor de una arquitectura libre de toda adscripción estilística. Goldfinger actúa aquí en una mesa de laboratorio donde pone a prueba sus reflexiones sobre el orden espacial, la composición, la escala, el carácter y la construcción.De esta forma la propuesta para Willow Road no puede explicarse exclusivamente en términos funcionales ni mecanicistas, sino que precisa una visión fenomenológica y al mismo tiempo mirarlo con amplitud para empezar a descubrir sus claves. Este hogar, que puede entenderse como vivienda burguesa y también representa un ejercicio moderno, ofrece la oportunidad de desvelar un modo de hacer, muy particular, en el que algunos arquitectos desarraigados y liberados del imperante tradicionalismo inglés y de cualquier dogmatismo, dejan a un lado el itinerario que cabría esperar en aquel momento y 'contaminan' la arquitectura moderna inglesa, para producir un panorama de influencias difícil de reconocer en cualquier otra localización. La huella de esta modernidad revisada, de espíritu inequívocamente moderno pero filtrado desde una actitud clásica, influye en la siguiente generación de arquitectos ingleses

  1. Sinkhole investigated at B.C. Hydro's Bennett Dam

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    The cause of a sinkhole which appeared in a roadway crossing an earth filled dam in B. C., was discussed. The hole measured 6 ft. across and 20 ft. deep, and occurred in B.C. Hydro's W.A.C. Bennett Dam which measures 600 ft. high, 2,600 ft. wide at the base and 35 ft. wide at the crest. The cause of the sinkhole is not known, but it is believed that a weakness in the dam may have found its way to the surface via a pipe connected to a bedrock settlement gauge buried within the dam. Sonar and ground penetrating radar were used to examine the area. The hole has been filled with gravel and monitoring continues. Experts do not anticipate immediate risk of dam failure. 1 fig

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

    Science.gov (United States)

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

    2015-01-01

    Landslides into valley bottoms can affect longitudinal profiles of rivers, thereby influencing landscape evolution through base-level changes. Large landslides can hinder river incision by temporarily damming rivers, but catastrophic failure of landslide dams may generate large floods that could promote incision. Dam stability therefore strongly modulates the effects of landslide dams and might be expected to vary among geologic settings. Here, we investigate the morphometry, stability, and effects on adjacent channel profiles of 17 former and current landslide dams in eastern Oregon. Data on landslide dam dimensions, former impoundment size, and longitudinal profile form were obtained from digital elevation data constrained by field observations and aerial imagery; while evidence for catastrophic dam breaching was assessed in the field. The dry, primarily extensional terrain of low-gradient volcanic tablelands and basins contrasts with the tectonically active, mountainous landscapes more commonly associated with large landslides. All but one of the eastern Oregon landslide dams are ancient (likely of order 103 to 104 years old), and all but one has been breached. The portions of the Oregon landslide dams blocking channels are small relative to the area of their source landslide complexes (0.4–33.6 km2). The multipronged landslides in eastern Oregon produce marginally smaller volume dams but affect much larger channels and impound more water than do landslide dams in mountainous settings. As a result, at least 14 of the 17 (82%) large landslide dams in our study area appear to have failed cataclysmically, producing large downstream floods now marked by boulder outwash, compared to a 40–70% failure rate for landslide dams in steep mountain environments. Morphometric indices of landslide dam stability calibrated in other environments were applied to the Oregon dams. Threshold values of the Blockage and Dimensionless Blockage Indices calibrated to worldwide

  3. 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

  4. Evaluation of spectral light management on growth of container-grown willow oak, nuttall oak and summer red maple

    Science.gov (United States)

    Plant response to blue, red, gray or black shade cloth was evaluated with willow oak (Quercus phellos L.), Nuttall oak (Quercus nuttallii Palmer, Nuttall) and Summer Red maple (Acer rubrum L. ‘Summer Red’) liners. Light transmitted through the colored shade cloth had no influence on germination of ...

  5. Physical Hydraulic Model of Side-Channel Spillway of Lambuk DAM, Bali

    Science.gov (United States)

    Harifa, A. C.; Sholichin, M.; Othman, F. B.

    2013-12-01

    The spillway is among the most important structures of a dam project. A spillway is designed to prevent overtopping of a dam at a place that is not designed for overtopping. Side-channel spillways are commonly used to release water flow from a reservoir in places where the sides are steep and have a considerable height above the dam. Experimental results were collected with a hydraulic model of the side-channel spillway for releasing the peak overflow of Lambuk Dam. This dam is, located on the Lambuk River, which is a tributary of the Yeh Hoo River ~ 34.6 km north of Denpasar on the island of Bali. The bituminous geomembrane faced dam is 24 m in height, with a 35-m wide spillway. The length of the side channel is 35 m long, with 58 m of transition channel, 67.37 m of chuteway channel and 22.71 m of stilling basin. The capacity of the spillway is 231.91 m3/s and the outlet works capacity is 165.28 m3/s. The reservoir is designed for irrigation and water supply. The purpose of this study was to optimize the designed of the structure and to ensure its safe operation. In hydraulic model may help the decision-makers to visualize the flow field before selecting a ';suitable' design. The hydraulic model study was performed to ensure passage of the maximum discharge at maximum reservoir capacity; to study the spillway approach conditions, water surface profiles, and flow patterns in the chuteway; and to reveal potential demerits of the proposed hydraulic design of various structures and explore solutions. The model was constructed at 1 : 40 scale, Reservoir topography was modeled using concrete, the river bed using sand and some gravel, the river berm using concrete, and the spillway and channel using Plexiglas. Water was measured using Rectangular contracted weir. Design floods (with return period in year) were Q2 = 111.40 m3/s, Q5 = 136.84 m3/s, Q10 = 159.32 m3/s, Q25 = 174.61 m3/s, Q50 = 185.13 m3/s, Q100 = 198.08 m3/s, Q200 = 210.55 m3/s, Q1000 = 231.91 m3/s and the

  6. Willow Creek Wildlife Mitigation Project. Final environmental assessment

    International Nuclear Information System (INIS)

    1995-04-01

    Today's notice announces BPA's proposal to fund land acquisition or acquisition of a conservation easement and a wildlife management plan to protect and enhance wildlife habitat at the Willow Creek Natural Area in Eugene, Oregon. This action would provide partial mitigation for wildlife and wildlife habitat lost by the development of Federal hydroelectric projects in the Willamette River Basin. The project is consistent with BPA's obligations under provisions of the Pacific Northwest Electric Power Planning and Conservation Act of 1980 as outlined by the Northwest Power Planning Council's 1994 Columbia River Basin Fish and Wildlife Program. BPA has prepared an environmental assessment (DOE/EA-1023) evaluating the proposed project. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement (EIS) is not required and BPA is issuing this FONSI

  7. Quality Testing of Short Rotation Coppice Willow Cuttings

    Directory of Open Access Journals (Sweden)

    Katrin Heinsoo

    2018-06-01

    Full Text Available The production and feasibility of Short Rotation Coppice depend on cutting early performance. The shoot and root biomass production of Salix cuttings in hydroponic conditions was studied. The amount of sprouted biomass after four weeks of growth depended on cutting the diameter, but the original position of the cutting along the rod or number of visible buds was not in correlation with biomass produced. Application of mineral fertilizer or soil originating from the willow plantation did not increase the total production. On the contrary, the addition of soil tended to decrease biomass production and we assumed this was a result of a shortage of light. Under the influence of fertilization, plants allocated greater biomass to roots. Comparison of different clones revealed that those with S. dasyclados genes tended to allocate less biomass to roots and the poorest-performing clone in our experiment, also had the lowest wood production in the plantation. The number of visible buds on the cutting was also clone-specific.

  8. 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.

  9. Dynamic analyzing procedures adopted for concrete-faced rockfill dams in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Tosun, H. [Dam Safety Association, Ankara (Turkey); Tosun, K. [TVT Hydrotech Bureau, Ankara (Turkey)

    2008-07-01

    A concrete faced rockfill dam (CFRD) has some advantages compared to other embankment types. The advantages include minimal settlement problems through the use of compacted rockfill; increased overall stability of the dam since the water pressure acts on the upstream face; and pore water pressure does not develop in the rockfill zone if it is well designed and constructed. It is thought that well-compacted CFRD has a high resistance to earthquake loading, as based on several factors including acceptable past performance of similar dams. While numerical solutions performed for this type of dams indicate that it is as safe as other embankment dams, their behavior is still questionable when they are subjected to severe seismic loading. This paper outlined the key principals of the dynamic analyzing method adopted for CFRDs in Turkey and summarized the practice of CFRDs with heights ranging from 54 to 135 metres throughout the country. Two-dimensional finite element models were executed to estimate displacements on the crest under the different loadings of earthquake. Dams that were discussed included the Kurtun Dam, the Torul Dam, the Atasu Dam, the Dim Dam, the Gordes Dam, and the Marmaris Dam. The paper also discussed the limitation about permanent settlement provided in the national dam specification and introduced the results obtained from a case study of the Pamukluk Dam located in southern Turkey. Geology and geotechnics as well as the embankment details and materials were discussed. The case study also summarized the selection of seismic parameters and dynamic analyses. 35 refs., 1 tab., 8 figs.

  10. Hydrogeophysical investigations at Hidden Dam, Raymond, California

    Science.gov (United States)

    Minsley, Burke J.; Burton, Bethany L.; Ikard, Scott; Powers, Michael H.

    2011-01-01

    Self-potential and direct current resistivity surveys are carried out at the Hidden Dam site in Raymond, California to assess present-day seepage patterns and better understand the hydrogeologic mechanisms that likely influence seepage. Numerical modeling is utilized in conjunction with the geophysical measurements to predict variably-saturated flow through typical two-dimensional dam cross-sections as a function of reservoir elevation. Several different flow scenarios are investigated based on the known hydrogeology, as well as information about typical subsurface structures gained from the resistivity survey. The flow models are also used to simulate the bulk electrical resistivity in the subsurface under varying saturation conditions, as well as the self-potential response using petrophysical relationships and electrokinetic coupling equations.The self-potential survey consists of 512 measurements on the downstream area of the dam, and corroborates known seepage areas on the northwest side of the dam. Two direct-current resistivity profiles, each approximately 2,500 ft (762 m) long, indicate a broad sediment channel under the northwest side of the dam, which may be a significant seepage pathway through the foundation. A focusing of seepage in low-topography areas downstream of the dam is confirmed from the numerical flow simulations, which is also consistent with past observations. Little evidence of seepage is identified from the self-potential data on the southeast side of the dam, also consistent with historical records, though one possible area of focused seepage is identified near the outlet works. Integration of the geophysical surveys, numerical modeling, and observation well data provides a framework for better understanding seepage at the site through a combined hydrogeophysical approach.

  11. Seepage problem in Papan dam and the treatment

    Energy Technology Data Exchange (ETDEWEB)

    Sharghi, A. [JTMA Co., Tehran (Iran, Islamic Republic of); Palassi, M. [Tehran Univ. (Iran, Islamic Republic of). Dept. of Civil Engineering

    2003-07-01

    The Papan dam in the Krygyz Republic is 97 metres high. It is located in the Osh Oblast, within a narrow and steep sided gorge on the Ak-Bura River, approximately 20 kilometres south of the City of Osh. The impoundment of the dam revealed large inflows of water to the downstream dam through the upper half of the dam and through the joints in the right abutment. A number of options were considered before a treatment method was selected. The causes of the leakage were poor grouting, and joints and fissures in the abutment. The remedial process involved the use of a plastic concrete cutoff wall extended from the crest of the dam to a depth of approximately 70 metres, in addition to the use of a grouting curtain in the right abutment. 2 figs.

  12. Design and Construction of Dams, Reservoirs, and Balancing Lakes

    International Nuclear Information System (INIS)

    Lemperiere, F.

    2003-01-01

    The general data presented in sections two and three gives an idea of the extreme diversity of the millions of very large or very small dams worldwide. Dam design and construction methods for the most usual types of large dams are presented and justified in section four. The possibility and usefulness of building as many dams in the 21. century as have been built in the 20. is analyzed in section six. (author)

  13. Estimates o the risks associated with dam failure

    Energy Technology Data Exchange (ETDEWEB)

    Ayyaswamy, P.; Hauss, B.; Hseih, T.; Moscati, A.; Hicks, T.E.; Okrent, D.

    1974-03-01

    The probabilities and potential consequences of dam failure in California, primarily due to large earthquakes, was estimated, taking as examples eleven dams having a relatively large population downstream. Mortalities in the event of dam failure range from 11,000 to 260,000, while damage to property may be as high as $720 million. It was assumed that an intensity IX or X earthquake (on the Modified Mercalli Scale) would be sufficient to completely fail earthen dams. Predictions of dam failure were based on the recurrence times of such earthquakes. For the dams studied, the recurrence intervals for an intensity IX earthquake varied between 20 and 800 years; for an intensity X between 50 and 30,000 years. For the Lake Chabot and San Pablo dams (respectively 20, 30 years recurrent earthquake times for a intensity X) the associated consequences are: 34,000 (Lake Chabot) and 30,000 (San Pablo) people killed; damage $140 million and $77 million. Evaculation was found to ameliorate the consequences slightly in most cases because of the short time available. Calculations are based on demography, and assume 10 foot floodwaters will drown all in their path and destroy all one-unit homes in the flood area. Damage estimates reflect losses incurred by structural damage to buildings and do not include loss of income. Hence the economic impact is probably understated.

  14. Dam spills and fishes

    International Nuclear Information System (INIS)

    1996-01-01

    This short paper reports the main topics discussed during the two days of the annual colloquium of the Hydro-ecology Committee of EdF. The first day was devoted to the presentation of the joint works carried out by EdF, the Paul-Sabatier University (Toulouse), the Provence St-Charles University (Marseille), the ENSAT (Toulouse) and the CEMAGREF (Lyon and Aix-en-Provence) about the environmental impact of dam spills on the aquatic flora and fauna downstream. A synthesis and recommendations were presented for the selection and characterization of future sites. The second day was devoted to the hydro-ecology study of the dam reservoir of Petit-Saut (French Guyana): water reoxygenation, quality evolution, organic matter, plankton, invertebrates and fishes. The 134 French dams concerned by water spills have been classified according to the frequency of spills, the variations of flow rates created, and their impacts on fishing, walking, irrigation, industry, drinking water, navigation, bathing. Particular studies on different sites have demonstrated the complexity of the phenomena involved concerning the impact on the ecosystems and the water quality. (J.S.)

  15. Grouting of karstic arch dam foundation

    Energy Technology Data Exchange (ETDEWEB)

    Young, J.; Rigbey, S. [Acres International, Niagara Falls, ON (Canada)

    2002-07-01

    A 200 m high arch dam and a 2000 MW underground power house complex is under development in the Middle East. The project is located in a highly seismic area in rugged, mountainous terrain. The arch dam is constructed on good quality limestone and dolomitic limestone rock mass, but it contains several zones of disturbed or sheared rock. The basement rock is slightly karstic with hydraulic conductivities in the order of 100 Lugeons. In order to get a satisfactory foundation surface for the dam, it will be necessary to excavate extensively and backfill with concrete. Because of the presence of many clay infilled cavities and fractures, geotechnicians are considering the installation of a multiple row grout curtain to a depth of 150 m below the dam foundation to ensure adequate seepage and uplift parameters when the reservoir is impounded. Initial grouting water pressure test results suggested that the grouting and drainage curtain should be extended to the left abutment beyond the current design. However, when horizontal slide models of the dam abutment were developed using the finite element program SEEPW, it was shown that there is no benefit to extending the length of grout curtains unless they are tied to an area of much lower hydraulic conductivity much deeper in the abutment. 1 tab., 5 figs.

  16. Predictions of total deformations in Jebba main dam by finite ...

    African Journals Online (AJOL)

    This paper examined the deformations of the Jebba Main Dam, Jebba Nigeria using the finite element method. The study also evaluated the predicted deformations and compared them with the actual deformations in the dam to identify possible causes of the observed longitudinal crack at the dam crest. The Jebba dam is a ...

  17. Biomass yield and fuel characteristics of short-rotation coppice (willow, poplar, empress tree)

    Energy Technology Data Exchange (ETDEWEB)

    Maier, J.; Vetter, R. [Institute for Land Management Compatible to Environmental Requirements, Muellheim (Germany)

    2004-07-01

    In two pedo-climatic different regions in the state of Baden-Wuerttemberg three shortrotation coppices willow, poplar and empress tree were tested with regard to their biomass productivity on arable land and to their properties for energetic use. Between 8 and 13 tons of dry matter per hectare and year could be produced under extensive cultivation conditions, over 15 tons with irrigation. Due to their composition, it can be assumed that their use as solid fuel in a biomass combustor is just as unproblematic as with forest timber. (orig.)

  18. Earthquake induced liquefaction analysis of Tendaho earth-fill dam ...

    African Journals Online (AJOL)

    fill dam, which is part of Tendaho Dam and Irrigation Project; the largest irrigation project in Ethiopia to date. The dam is located in the most seismic part of Ethiopia and was originally designed to be founded on potentially liquefiable alluvium ...

  19. 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...

  20. Ririe Dam Release Test Assessment

    Science.gov (United States)

    2013-06-01

    Notes HEC - RAS Location Station (ft) Observation Notes 1420 Ririe Dam Ririe Dam 119,880 Gates opened and initial release started. 1455 115th St...16°F air temperature. Table A2. Observations made on 11 February 2013. Time Location Notes HEC - RAS Location Station (ft) Observation Notes...ERDC/CRREL TR-13-10 52 Time Location Notes HEC - RAS Location Station (ft) Observation Notes Travel Time* (sec) Vel.** (fps) 1224 5th

  1. Grouting design for slope stability of kedung uling earthfill dam

    Directory of Open Access Journals (Sweden)

    Najib

    2018-01-01

    Full Text Available Kedung Uling earthfill dam locates at Wonogiri Regency, Central Java, Indonesia. The dam encountered sliding and settlement at the embankment wall. To minimize sliding and settlement and to optimize the dam, both field investigation and laboratory tests have been proceeded for slope stability analysis and remedial embankment wall. Soil and rock investigation around the dam, which is followed by 10 core drillings, have been conducted. Laboratory tests such as direct shear and index properties have also been carried on. The results were further used for dam slope stability model using slide 6.0 and were used to analyzed factor of safety (FS of Kedunguling dam. 10 conditions of dam were simulated and strengthening body of dam with grouting was designed. The results showed two conditions, which are condition of maximum water level with and without earthquake at downstream, were unsatisfy Indonesia National Standard (SNI for building and infrastructure. These conditions can be managed by using grouting for increasing stabilization of embankment wall. By setting up grouting, factor of safety increases and meet the SNI standard requirement.

  2. Non uniform nature of recorded ground accelerations at dam foundation interface

    Energy Technology Data Exchange (ETDEWEB)

    Ghaemian, Mohsen; Gilani, Morteza Sohrabi [Sharif University of Technology, Tehran, (Iran, Islamic Republic of); Noorzad, Ali [Power and Water University of Technology, Tehran, (Iran, Islamic Republic of)

    2010-07-01

    The Karun III is a double curved concrete arch dam located in Iran which was used to investigate earthquake motions and dam responses. This paper presented the study of the Karun III dam foundation interface. Using an array of 15 accelerometers, two major events that occurred on 2007.11.20 and 2007.11.21 were recorded during dam operation with a PGA at crest of 0.312 g and 0.109.g respectively. A finite element model of Karun III dam was performed. The response of the Karun III dam during the 2007 earthquake was investigated using the NSAD-DRI program. It was found that the motion of the dam foundation interface is non-uniform. There is a time shift and amplification at the abutment compared to those at the base of the dam. The results showed that the spatially varying earthquake assumption is in good agreement with the recorded displacement of the dam.

  3. Results from software based empirical models of and standing biomass for poplar and willow grown as short rotation coppice

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, M.E.; Morgan, G.W.; Brewer, A.C. (Forest Research Biometrics, Surveys and Statistics Division, Forest Research, Wrecclesham (United Kingdom))

    2007-07-01

    Statistical analysis was used to create a model for estimating the quantity of biomass produced by crops of poplar and willow grown as short rotation coppice. This model was converted into a software system as described here. The software is currently available for scientific demonstration. (orig.)

  4. Verifying Pressure of Water on Dams, a Case Study

    Directory of Open Access Journals (Sweden)

    Temel Bayrak

    2008-09-01

    Full Text Available Sensing and monitoring deformation pattern of dams is often one of the most effective ways to understand their safety status. The main objective of the present study is to find the extent to which rising reservoir level affects the mechanism of deformation of the Yamula dam under certain changes in the reservoir level conditions during the first filling period. A new dynamic deformation analysis technique was developed to analyze four geodetic monitoring records consisting of vertical and horizontal displacements of nine object points established on the dam and six reference points surrounding it, to see whether the rising reservoir level is responsible for the vertical and horizontal deformations during the first filling period. The largest displacements were determined in the middle points of the dam construction. There is an apparent linear relationship between the dam subsidence and the reservoir level. The dynamic deformation model was developed to model this situation. The model infers a causative relationship between the reservoir level and the dam deformations. The analysis of the results determines the degree of the correlation between the change in the reservoir level and the observed structural deformation of the dam.

  5. Detection of water leaks in the dam Joumine and study of sedimentation in the dam Ghezela by nuclear method

    International Nuclear Information System (INIS)

    Sari Souha

    2013-01-01

    The objective of this study is to determinate the paths of leaks observed in the dam Joumine and to identify the origin of salinity in the drain D2. In addition, the evaluation of the sedimentation measurement of suspended elements in the dam Ghezela is our second objective. The Joumine dam located in the North-east of Tunisia (governorate of Bizerte), was built in 1983 has an upstream watershed area of 418 km 2 . The reservoir capacity is 130 Mm 3 . This dam observed a water leakage from its implementation at the two drains D1 and D2 with a emerging flow rate reached a value close to 500 l/s, about 16 pour cent of its capacity. The injection of an insulating material in Karsts networks reduces the leakage rate to a value of 120 l / s in 1993 and 88 l / s in 2013, but this decrease was accompanied by an increase in salinity level in D2. The results from a multidisciplinary approach showed that the leakage path from the left bank of the reservoir where the leak was first detected, heading both D1 and D2 drains and the salinity in drain D2 due to the dissolution of the gypsum layer downstream of the dam and the contribution of brackish water from the left bank. The Ghezela dam located in the same area, was built in 1984 has an upstream watershed area of 48 km 2 . This dam has been an increase in sedimentation of 0.3 million m3 in 1994 to 1.7 million m 3 in 2010. In this study, the suspended elements were measured with a nuclear probe composed by a radioactive source of americium 241 and a NaI detector trained by a boat at different depth in the reservoir.

  6. Pearl Harbor: lessons for the dam safety community

    Energy Technology Data Exchange (ETDEWEB)

    Martin, T.E. [AMEC Earth and Environmental Ltd., Burnaby, BC (Canada)

    2001-10-01

    Every good dam safety program must be based on surveillance and emergency response planning. The same principles apply to the gathering of information for military intelligence and the planning of defence tactics. Lessons learned from failure have spurred the advancement of dam engineering. Dam safety experts can benefit from the inadequacies encountered by the military community, with the most famous occurring on December 7, 1941 in Pearl Harbor. Both intelligence gathering and contingency response planning failed miserably. The data was not properly disseminated, interpreted, analysed. The proper response to the situation was not initiated. Human error and failure to communicate are the two main reasons that explain the debacle. The inquiries into the tragedy at Pearl Harbor provided valuable lessons, related to individual and organizational failures, which the authors shared in this presentation. The relevance to dam safety was made. All Federal Bureau of Investigation (FBI) agents must read the lessons drawn from Pearl Harbor, as they have responsibility for dam safety. 4 refs.

  7. Towards a dams safety management system for Angola

    OpenAIRE

    Camilo, V.; Silva, A.; Costa, R.; Barateiro, J.; Portela, E. A.; Fonseca, J.

    2015-01-01

    Dams have contributed to the human development and have brought many benefits, such as delivering hydropower, irrigating agricultural fields, supplying drinking water, or just for navigational and recreational purposes. Nevertheless, dams are critical structures that raise multiple concerns and risks associated with the ecological, social and economic impact. Angola has a rich and complex network of water basins and dams that serves different strategic purposes as defined in it...

  8. Remote Sensing of Deformation of a High Concrete-Faced Rockfill Dam Using InSAR: A Study of the Shuibuya Dam, China

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    2016-03-01

    Full Text Available Settlement is one of the most important deformation characteristics of high concrete faced rockfill dams (CFRDs, >100 m. High CFRDs safety would pose a great threat to the security of people’s lives and property downstream if this kind of deformation were not to be measured correctly, as traditional monitoring approaches have limitations in terms of durability, coverage, and efficiency. It has become urgent to develop new monitoring techniques to complement or replace traditional monitoring approaches for monitoring the safety and operation status of high CFRDs. This study examines the Shuibuya Dam (up to 233.5 m in height in China, which is currently the highest CFRD in the world. We used space-borne Interferometric Synthetic Aperture Radar (InSAR time series to monitor the surface deformation of the Shuibuya Dam. Twenty-one ALOS PALSAR images that span the period from 28 February 2007 to 11 March 2011 were used to map the spatial and temporal deformation of the dam. A high correlation of 0.93 between the InSAR and the in-situ monitoring results confirmed the reliability of the InSAR method; the deformation history derived from InSAR is also consistent with the in-situ settlement monitoring system. In addition, the InSAR results allow continuous investigation of dam deformation over a wide area that includes the entire dam surface as well as the surrounding area, offering a clear picture continuously of the dam deformation.

  9. 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

  10. National Program for Inspection of Non-Federal Dams. Miller Pond Dam (CT 00154), Thames River Basin, Waterford, Connecticut. Phase I Inspection Report.

    Science.gov (United States)

    1980-08-01

    Road and adjacent to the Brook are likely to be impacted by dam failure. Because a breach of Miller Pond Dam would cause severe economic loss and the...TO THE ASSUMED SPILL CREST ELEVATION 3 WATER %. WACE ELEATCRS. SHOREI I NE AND 7AI NGTER COGRATIONS ARE APPROXIMATE, AS OBTAINED Dl"F I -t DAM INSECTION

  11. Seismic Analysis of Concrete Dam by Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Rozaina Ismail

    2017-01-01

    Full Text Available This paper reports a brief study on linear seismic analysis of Sg. Kinta Concrete Dam. The analysis was conducted in order to determine the performance and behaviour of the dam under seismic excitation. The dam was modelled as two-dimensional and developed based on the design drawing that is obtained from Angkasa Consulting Services Sdn. Bhd. The seismic analysis of the dam is conducted using finite element analysis software package LUSAS 14.3 and the dam has been analyse as a plain stress problem with a linear consideration. A set of historic data, with E1 Centro earthquake acceleration of about 0.50g is used as an earthquake excitation. The natural frequency and mode shape up to fifth mode of the dam has been obtained from the analysis to show the differences of the stress and deformation between each mode. The maximum horizontal and vertical stress of Sg. Kinta dam was found and the distribution of them was discussed in form of contours. The deformation of the dam were also been discussed by comparing the maximum displacement for each mode shaped.

  12. Alteration of stream temperature by natural and artificial beaver dams.

    Science.gov (United States)

    Weber, Nicholas; Bouwes, Nicolaas; Pollock, Michael M; Volk, Carol; Wheaton, Joseph M; Wathen, Gus; Wirtz, Jacob; Jordan, Chris E

    2017-01-01

    Beaver are an integral component of hydrologic, geomorphic, and biotic processes within North American stream systems, and their propensity to build dams alters stream and riparian structure and function to the benefit of many aquatic and terrestrial species. Recognizing this, beaver relocation efforts and/or application of structures designed to mimic the function of beaver dams are increasingly being utilized as effective and cost-efficient stream and riparian restoration approaches. Despite these verities, the notion that beaver dams negatively impact stream habitat remains common, specifically the assumption that beaver dams increase stream temperatures during summer to the detriment of sensitive biota such as salmonids. In this study, we tracked beaver dam distributions and monitored water temperature throughout 34 km of stream for an eight-year period between 2007 and 2014. During this time the number of natural beaver dams within the study area increased by an order of magnitude, and an additional 4 km of stream were subject to a restoration manipulation that included installing a high-density of Beaver Dam Analog (BDA) structures designed to mimic the function of natural beaver dams. Our observations reveal several mechanisms by which beaver dam development may influence stream temperature regimes; including longitudinal buffering of diel summer temperature extrema at the reach scale due to increased surface water storage, and creation of cool-water channel scale temperature refugia through enhanced groundwater-surface water connectivity. Our results suggest that creation of natural and/or artificial beaver dams could be used to mitigate the impact of human induced thermal degradation that may threaten sensitive species.

  13. National Program for Inspection of Non-Federal Dams. Tihonet Pond Number 2 Dam (MA 00030), Massachusetts Coastal Basin, Wareham, Massachusetts. Phase I Inspection Report.

    Science.gov (United States)

    1981-07-01

    drainage area above the dam is 8.1 square miles. The watershed is characterized by irregular topography: cranberry bogs, small ponds and depressions ...and recreational purposes. Water from this pond is used in the U irrigation of cranberry bogs downstream. The maximum storage capacity of the dam is...295-1000 g. PURPOSE OF DAM The dam impounds Tihonet Pond which is a storage reservoir 4_- 4 4: . * used principally for irrigating cranberry bogs which

  14. National Program for Inspection of Non-Federal Dams. Paper Mill Pond Dam (CT 00621), Connecticut River Basin, Vernon, Connecticut. Phase I Inspection Report.

    Science.gov (United States)

    1981-03-01

    HYDROLOGIC AND HYDRAULIC COMPUTATIONS E INFORMATION AS CONTAINED IN THE NATIONAL INVENTORY OF DAMS ,v ’walL.it, AM I OVERVIEV \\ PHOTO Iv 390 L-( ibb~ ~5~4 N...AS-A144 539 NATIONAL PROGRAM FOR INSPEGTION 0F NON-FEDERAL DAMS / PAPER MIL POND DAM (.(U CORPS OF ENGINEERS WALTHAM A S MA NEW ENGLANA DIV MAR...CATALOG NUMBER CT 00621A 4 TITLE (amdSubtile) S. TYPE OF REPORT & PERIOD’COVERED Paper Mill Pond Dam INSPECTION REPORT NATIONAL PROGRAM FOR INSPECTION

  15. Hydraulic fracture considerations in oil sand overburden dams

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R.; Madden, B.; Danku, M. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2008-07-01

    This paper discussed hydraulic fracture potential in the dry-filled temporary dams used in the oil sands industry. Hydraulic fractures can occur when reservoir fluid pressures are greater than the minimum stresses in a dam. Stress and strain conditions are influenced by pore pressures, levels of compaction in adjacent fills as well as by underlying pit floor and abutment conditions. Propagation pressure and crack initiation pressures must also be considered in order to provide improved hydraulic fracture protection to dams. Hydraulic fractures typically result in piping failures. Three cases of hydraulic fracture at oil sands operations in Alberta were presented. The study showed that hydraulic fracture failure modes must be considered in dam designs, particularly when thin compacted lift of dry fill are used to replace wetted clay cores. The risk of hydraulic fractures can be reduced by eliminating in situ bedrock irregularities and abutments. Overpressure heights, abutment sloping, and the sloping of fills above abutments, as well as the dam's width and base conditions must also be considered in relation to potential hydraulic fractures. It was concluded that upstream sand beaches and internal filters can help to prevent hydraulic fractures in dams in compacted control zones. 5 refs., 16 figs.

  16. Characterization of landslide dams in the San Juan province (Argentina)

    Science.gov (United States)

    Penna, Ivanna; Longchamp, Celine; Derron, Marc-Henri; Jaboyedoff, Michel

    2013-04-01

    River blockages caused by landslide deposition are common phenomena in active mountain chains, influencing erosion-sedimentation patterns and acting as primary and secondary hazards. Regional scale analyses regarding their spatial distribution and morphometry allow establishing boundary conditions for their occurrence and stability, and determine differences among regions with different landscape and climatic conditions. Owing to the combination of endogenous and exogenous factors, landslide dams are frequent phenomena in the Andes. In the Argentinean NW and the Patagonian Andes, previous studies showed that stability of landslide dams determined by morphometric parameters generally matched satisfactorily with dam behavior, with some exceptions in which climatic component played an important role in dam longevity. Aiming to expand the knowledge of landslide dams in the Argentinean Andes, in this work we analyzed the stability of rock avalanche dams in the Pampeam flat slab subduction zone. In the study area, mountain dynamics creates suitable conditions for the occurrence of 34 rock avalanches with volumes up to 0.3 km3. They developed in deeply carved valleys (Cordillera) and Inter-thrust valleys (Precordillera). 22 impoundments of rivers resulted from channelized rock avalanches with long runouts (4-10 km) that blocked tributaries rivers, but most of them by rock avalanches that filled the valley bottom, with run up in the opposite slope and limited movement parallel to the valley axis. Most of the dams breached in unknown times, except for the last event that occurred on November 12th 2005. The quantification of morphometric parameters and contributing areas indicates the existence of dams with dimensionless blockage index above 2.75 (stable domain) and below 3.08 (instable domain). The Los Erizos dam in our study area and the Barrancas dam in the Patagonian Andes show that besides morphometric parameters, climatic conditions are decisive. Stable landslide dams

  17. 3. Rethinking Borders in Empire and Nation at the Foot of the Willow Palisade

    OpenAIRE

    E.Bulag, Uradyn

    2015-01-01

    Prologue: stony wars at the foot of the willow palisade Every year, on the fifth day of the fifth lunar month, i.e. the traditional Duanwu Festival (also known as Dragon Boat Festival or Double Fifth Festival), people in Wangsiyingzi and the neighbouring village Sifangtai, just about one and half kilometres to the south, would climb atop a small mountain that lies between the two villages. Instead of racing dragon-headed boats as is the practice in south China, where the tradition first start...

  18. Engineers find climbing techniques work well for dam inspections

    Energy Technology Data Exchange (ETDEWEB)

    O`Shea, M.; Graves, A. [Bureau of Reclamation, Denver, CO (United States)

    1996-10-01

    Climbing techniques adopted by the Bureau of Reclamation to inspect previously inaccessible or difficult to reach features at dams are described. Following the failure of the steel radial-arm gate at Folsom Dam, engineers mounted an effort to reach and inspect the dam`s seven other spillway gates. This close-up examination was performed to: (1) determine the condition of these gates; and (2) gather clues about the failure of the one gate. The access techniques described involved mountaineering techniques, as opposed to high scaling techniques, performed with dynamic and static nylon kermantle ropes.

  19. Responses of riparian reptile communities to damming and urbanization

    Science.gov (United States)

    Hunt, Stephanie D.; Guzy, Jacquelyn C.; Price, Steven J.; Halstead, Brian J.; Eskew, Evan A.; Dorcas, Michael E.

    2013-01-01

    Various anthropogenic pressures, including habitat loss, threaten reptile populations worldwide. Riparian zones are critical habitat for many reptile species, but these habitats are also frequently modified by anthropogenic activities. Our study investigated the effects of two riparian habitat modifications-damming and urbanization-on overall and species-specific reptile occupancy patterns. We used time-constrained search techniques to compile encounter histories for 28 reptile species at 21 different sites along the Broad and Pacolet Rivers of South Carolina. Using a hierarchical Bayesian analysis, we modeled reptile occupancy responses to a site's distance upstream from dam, distance downstream from dam, and percent urban land use. The mean occupancy response by the reptile community indicated that reptile occupancy and species richness were maximized when sites were farther upstream from dams. Species-specific occupancy estimates showed a similar trend of lower occupancy immediately upstream from dams. Although the mean occupancy response of the reptile community was positively related to distance downstream from dams, the occupancy response to distance downstream varied among species. Percent urban land use had little effect on the occupancy response of the reptile community or individual species. Our results indicate that the conditions of impoundments and subsequent degradation of the riparian zones upstream from dams may not provide suitable habitat for a number of reptile species.

  20. Sinkhole investigated at B.C. Hydro`s Bennett Dam

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-07-01

    The cause of a sinkhole which appeared in a roadway crossing an earth filled dam in B. C., was discussed. The hole measured 6 ft. across and 20 ft. deep, and occurred in B.C. Hydro`s W.A.C. Bennett Dam which measures 600 ft. high, 2,600 ft. wide at the base and 35 ft. wide at the crest. The cause of the sinkhole is not known, but it is believed that a weakness in the dam may have found its way to the surface via a pipe connected to a bedrock settlement gauge buried within the dam. Sonar and ground penetrating radar were used to examine the area. The hole has been filled with gravel and monitoring continues. Experts do not anticipate immediate risk of dam failure. 1 fig.

  1. Analytical Solution and Application for One-Dimensional Consolidation of Tailings Dam

    Directory of Open Access Journals (Sweden)

    Hai-ming Liu

    2018-01-01

    Full Text Available The pore water pressure of tailings dam has a very great influence on the stability of tailings dam. Based on the assumption of one-dimensional consolidation and small strain, the partial differential equation of pore water pressure is deduced. The obtained differential equation can be simplified based on the parameters which are constants. According to the characteristics of the tailings dam, the pore water pressure of the tailings dam can be divided into the slope dam segment, dry beach segment, and artificial lake segment. The pore water pressure is obtained through solving the partial differential equation by separation variable method. On this basis, the dissipation and accumulation of pore water pressure of the upstream tailings dam are analyzed. The example of typical tailings is introduced to elaborate the applicability of the analytic solution. What is more, the application of pore water pressure in tailings dam is discussed. The research results have important scientific and engineering application value for the stability of tailings dam.

  2. 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.

  3. DETERMINATION OF FLAVONOIDS OF WILLOW TRIANDRA (SALIX TRIANDRA L., GROWING IN THE NORTH CAUCASUS

    Directory of Open Access Journals (Sweden)

    E. G. Sannikova

    2016-01-01

    Full Text Available Plants of willow genus are rich in various flavonoids. In 60-e years of the XX century the works of V. A. Kompantsev showed that leaves of willow triandra, growing in the North Caucasus, contain up to 5% of rutin. The method, which required long sample preparation (extraction of the raw material with TLC, chromatographic layer extraction with methanol, removal of the solvent, dissolution in ethanol, optical density measurements was used. Currently available and simple methods for the determination of rutin in plant material are described. Given that leaves of Salix triandra contain significant amounts of rutin and can be a potential raw material for the creation of medicines on their basis, it is essential to determine the amount of flavonoids in the leaves of Salix triandra and its branches.The purpose of this study is determination of the amount of flavonoids in the willow triandra, growing in the North Caucasus, depending on the place and time of collection.Methods. TLC and the method of differential spectrophotometry were used to study chemical reactions. Results. The presence of flavonoids in various vegetative plant organs was established using qualitative reactions (cyanidin test; boric-citric reaction; the reaction with solution of lead acetate and solution of ammonia. Rutin and quercetin flavonoids in the presence of standard samples were identified using TLC. the method of differential spectrophotometry, based on the reaction of flavonoids with aluminum chloride was used for the quantitative determination of the amount of flavonoids. It is shown that the greatest quantity of flavonoids amount accumulated in the leaves (up to 3.76%, its value in branches is slightly smaller (up to 3.26%. The branches without leaves have almost 10 times less flavonoids. It was established experimentally that the accumulation of flavonoids in raw material of Salix triandra is dependent on the place and time of

  4. National Dam Safety Program. Lakeview Estates Dam (MO 11004), Mississippi - Kaskaskia - St. Louis Basin, Warren County, Missouri. Phase I Inspection Report.

    Science.gov (United States)

    1979-09-01

    ificatiozh Distributon/ Availabilit oe LAKEVIEW ESTATES DAM WARREN COUNTY, MISSOURI MISSOURI INVENTORY NO. 11004 PHASE I INSPECTION REPORT NATIONAL DAM SAFETY...and *impounds less than 1,000 acre-feet of water . Our inspection and evaluation indicates that the spill- way of Lakeview Estates Dam does not meet...not be measured because of high reservoir level, scalloping near the crest and a berm just under the water surface. Limestone riprap in sizes from sand

  5. Seismic Fortification Analysis of the Guoduo Gravity Dam in Tibet, China

    Directory of Open Access Journals (Sweden)

    Peng Lin

    2015-01-01

    Full Text Available The primary aim of this research was to analyze the seismic performance of the Guoduo gravity dam. A nonlinear FEM method was implemented to study the deformation, stress, and overall stability of dam under both static and dynamic loading conditions, including both normal and overloading conditions. A dam seismic failure risk control method is proposed based on the cracking mechanism induced by the dynamic load to ensure dam safety and stability. Numerical simulation revealed that (1 under normal static and dynamic loading the symmetry of the displacement distributions is good, showing that the dam abutments and riverbed foundation have good overall stiffness. The stress distribution is a safe one for operation under both normal water loading and seismic loading. (2 Attention should be paid to the reinforcement design of outlets of the diversion dam monoliths, and enhance the capability of sustaining that tensile stress of dam monoliths. (3 The shape of the dam profile has a significant effect on the dynamic response of the dam. (4 By employing the “overload safety factor method,” the overall seismic fortification is as follows: K1=1.5, K2= 2~3, and K3= 3~4.

  6. In the Land of the Dammed: Assessing Governance in Resettlement of Ghana’s Bui Dam Project

    Directory of Open Access Journals (Sweden)

    Kwabena Asiama

    2017-11-01

    Full Text Available Resettlement resulting from dam construction has raised several concerns due to the negative aftermath impacts. In Ghana, the construction of three hydroelectric dams resulted in large-scale resettlements. Given the little experience that Ghana has in resettlements, it is necessary for a robust monitoring structure for resettlements. However, this was not available in the last resettlement undertaken for the Bui Dam Project. This paper aims at developing an assessment framework for monitoring resettlement activities on customary lands from a good governance perspective. Based on four good governance principles, transparency, public participation and inclusiveness, equity and rule of law and accountability, a good governance assessment framework is built and applied to the Bui Dam Project using a case study approach. Data were collected through interviews and focus group discussion with the key actors of the resettlement project. It was first found that the planning stage of the resettlement came out with a robust plan that was to prevent the impoverishment of the affected persons. However, in the implementation of the resettlement, not all good governance principles were adhered to. In conclusion, it was found that by deconstructing the resettlement process with a good governance framework, the problematic areas of the resettlement can be effectively differentiated between the planning and implementation phases.

  7. 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...

  8. National Inventory of Dams Coastal California Extract 2010

    Data.gov (United States)

    California Natural Resource Agency — 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...

  9. Willow Creek Wildlife Mitigation Project. Final Environmental Assessment.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    Today`s notice announces BPA`s proposal to fund land acquisition or acquisition of a conservation easement and a wildlife management plan to protect and enhance wildlife habitat at the Willow Creek Natural Area in Eugene, Oregon. This action would provide partial mitigation for wildlife and wildlife habitat lost by the development of Federal hydroelectric projects in the Willamette River Basin. The project is consistent with BPA`s obligations under provisions of the Pacific Northwest Electric Power Planning and Conservation Act of 1980 as outlined by the Northwest Power Planning Council`s 1994 Columbia River Basin Fish and Wildlife Program. BPA has prepared an environmental assessment (DOE/EA-1023) evaluating the proposed project. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement (EIS) is not required and BPA is issuing this FONSI.

  10. The environmental impact of large dams

    International Nuclear Information System (INIS)

    Razvan, E.

    1992-01-01

    The campaigns of conservationist groups against dams are generally based on rather emotional issues. This paper puts the situation in a more rational perspective, by analysing the various claims which tend to be put forward concerning the impacts of large dams, examining the validity of the arguments, looking at ways in which any adverse effects can be mitigated, and presenting the complexity of the problems. (author)

  11. Discussion on the Safety Factors of Slopes Recommended for Small Dams

    Directory of Open Access Journals (Sweden)

    Jan Vrubel

    2017-01-01

    Full Text Available The design and assessment of the slope stability of small embankment dams is usually not carried out using slope stability calculations but rather by the comparison of proposed or existing dam slopes with those recommended by technical standards or guidelines. Practical experience shows that in many cases the slopes of small dams are steeper than those recommended. However, most of such steeper slopes at existing dams do not exhibit any visible signs of instability, defects or sliding. For the dam owner and also for dam stability engineers, the safety of the slope, expressed e.g. via a factor of safety, is crucial. The aim of this study is to evaluate the safety margin provided by recommended slopes. The factor of safety was evaluated for several dam shape and layout variants via the shear strength reduction method using PLAXIS software. The study covers various dam geometries, dam core and shoulder positions and parameter values of utilised soils. Three load cases were considered: one with a steady state seepage condition and two with different reservoir water level drawdown velocities – standard and critical. As numerous older small dams lack a drainage system, variants with and without a toe drain were assessed. Calculated factors of safety were compared with required values specified by national standards and guidelines.

  12. Investigation of Solid Energy Potential of Wood and Bark Obtained from Four Clones of a 2-Year Old Goat Willow

    International Nuclear Information System (INIS)

    Han, Sim-Hee; Shin, Soo-Jeong

    2014-01-01

    To investigate the solid raw material characteristics of willow (Salix caprea) bark and woody core, this study analyzed overall chemical composition, monosaccharide composition, ash content, and main ash composition of both tree components. Significant differences were observed between the two in terms of chemical composition, carbohydrate composition, ash content, and major inorganics. The ash content in bark was 3.8–4.7%, compared with 0.6–1.1% in the woody core. Polysaccharide content in the woody core was 62.8–70.6% but was as low as 44.1–47.6% in the bark. The main hemicelluloses consisting of monosaccharides were xylose in the case of the woody core, and xylose, galactose, and arabinose in the case of bark. Woody core biomass of willow provides superior solid fuel raw material, as compared with bark biomass, with higher heating values, less ash content, and less slagging-causing material.

  13. Investigation of Solid Energy Potential of Wood and Bark Obtained from Four Clones of a 2-Year Old Goat Willow

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sim-Hee [Department of Forest Genetic Resources, Korea Forest Research Institute, Suwon (Korea, Republic of); Shin, Soo-Jeong, E-mail: soojshin@cbnu.ac.kr [Department of Wood and Paper Science, Chungbuk National University, Cheongju (Korea, Republic of)

    2014-01-31

    To investigate the solid raw material characteristics of willow (Salix caprea) bark and woody core, this study analyzed overall chemical composition, monosaccharide composition, ash content, and main ash composition of both tree components. Significant differences were observed between the two in terms of chemical composition, carbohydrate composition, ash content, and major inorganics. The ash content in bark was 3.8–4.7%, compared with 0.6–1.1% in the woody core. Polysaccharide content in the woody core was 62.8–70.6% but was as low as 44.1–47.6% in the bark. The main hemicelluloses consisting of monosaccharides were xylose in the case of the woody core, and xylose, galactose, and arabinose in the case of bark. Woody core biomass of willow provides superior solid fuel raw material, as compared with bark biomass, with higher heating values, less ash content, and less slagging-causing material.

  14. 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

  15. Some aspects in the legal regulation of the dams

    International Nuclear Information System (INIS)

    Tancev, Ljubomir

    1996-01-01

    In order to ensure high quality and low cost design and building of dams and appurtenant structures, as well as safe exploitation, it is obvious to have appropriate legislation. Keeping in mind that the dams are unique structures, for the design stage the legislation should be less strong. For the next phases - building, maintenance and exploitation - detail and rigorous legislation is recommended. It is emphasised that the engineers should have more freedom designing the dams, but they should be obvious to apply the most recent achievement in the field of the dam design and construction. For illustration, some aspects of three important questions are discussed - 1) the choice of maximum flood discharge, 2) the application of new materials and construction methods and 3) the application of modern methods for static and dynamic analysis of dams. (Author)

  16. Analytical Solution and Application for One-Dimensional Consolidation of Tailings Dam

    OpenAIRE

    Liu, Hai-ming; Nan, Gan; Guo, Wei; Yang, Chun-he; Zhang, Chao

    2018-01-01

    The pore water pressure of tailings dam has a very great influence on the stability of tailings dam. Based on the assumption of one-dimensional consolidation and small strain, the partial differential equation of pore water pressure is deduced. The obtained differential equation can be simplified based on the parameters which are constants. According to the characteristics of the tailings dam, the pore water pressure of the tailings dam can be divided into the slope dam segment, dry beach seg...

  17. 33 CFR 117.705 - Beaver Dam Creek.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Beaver Dam Creek. 117.705 Section 117.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.705 Beaver Dam Creek. The draw of the...

  18. Dams. Bulletin of the technical service of electric power and big dams; Barrages. Bulletin du service technique de l`energie electrique et des grands barrages

    Energy Technology Data Exchange (ETDEWEB)

    Davard, J.

    1997-12-31

    The Dams bulletin reports on technical news concerning big French dams in operation. This issue comprises 5 papers. Two of them are examples of granting problems which led to the dismantling of the dams of Kernansquillec (Cotes d`Armor, France) and Maisons-Rouges (Indre-et-Loire, France) for economical and environmental reasons. The 3 other papers concern the life of French dams (technical control reports of the French dams in operation), the activities of the control service (annual inspections, preparation of draining operations, renewing of granting), and some general information (organisation of competent authorities, colloquium reports, hydro-power production during the first quarter of 1997). (J.S.)

  19. Fosfortab fra det dyrkede areal til Stevning Dam, Hindemaj og Haderslev Dam

    DEFF Research Database (Denmark)

    Andersen, Hans Estrup; Heckrath, Goswin; Thodsen, Hans

    Størrelsen af dyrkningsbidraget til søerne i Haderslev Dam-systemet er vurderet med to forskellige metoder til at udgøre ca. 42 % af den samlede tilførsel. En risikokortlægning med det nye, danske P-indeks viser, at i alt 15 % af det dyrkede areal er i højrisiko mht. fosfortab. P-indeks-kortlægni......Størrelsen af dyrkningsbidraget til søerne i Haderslev Dam-systemet er vurderet med to forskellige metoder til at udgøre ca. 42 % af den samlede tilførsel. En risikokortlægning med det nye, danske P-indeks viser, at i alt 15 % af det dyrkede areal er i højrisiko mht. fosfortab. P...

  20. The silviculture, nutrition and economics of short rotation willow coppice in the uplands of mid-Wales

    Energy Technology Data Exchange (ETDEWEB)

    Heaton, R J; Randerson, P F; Slater, F M

    2000-07-01

    The potential of short rotation coppice as a biomass crop on land over 250m (the uplands) of mid Wales was studied. The results found in this study indicate that growing short rotation coppice willow in the uplands is a viable proposition with regard to establishment success and yields. In the event of a secure wood chip market in Wales, returns to the grower would be comparable to those from sheep production. (author)

  1. Dam-break studies for mine tailings impoundments

    International Nuclear Information System (INIS)

    Jeyapalan, J.K.

    1982-01-01

    This paper describes simple procedures for performing dam-break analyses. Tailings from dam failures usually liquefy and flow for substantial distances as a viscous fluid. The prediction of the possible extent of flow slide movement is illustrated using two case histories. Topics considered include the flow behavior of liquefied talings, dimensionsless numbers for mine tailings and associated flow regimes, laminar flow, and turbulent flow. The potential inundation regions downstream of mine tailings dams are assessed. It is concluded that instances of flow slides of mine waste embankments indicate that the failure of these structures has considerable potential for damage to life and property in many cases

  2. Permeability analysis of Asbuton material used as core layers of water resistance in the body of dam

    Science.gov (United States)

    Rahim, H.; Tjaronge, M. W.; Thaha, A.; Djamaluddin, R.

    2017-11-01

    In order to increase consumption of the local materials and national products, large reserves of Asbuton material about 662.960 million tons in the Buton Islands became an alternative as a waterproof core layer in the body of dam. The Asbuton material was used in this research is Lawele Granular Asphalt (LGA). This study was an experimental study conducted in the laboratory by conducting density testing (content weight) and permeability on Asbuton material. Testing of the Asbuton material used Falling Head method to find out the permeability value of Asbuton material. The data of test result to be analyzed are the relation between compaction energy and density value also relation between density value and permeability value of Asbuton material. The result shows that increases the number of blow apply to the Asbuton material at each layer will increase the density of the Asbuton material. The density value of Asbuton material that satisfies the requirements for use as an impermeable core layer in the dam body is 1.53 grams/cm3. The increase the density value (the weight of the contents) of the Asbuton material will reduce its permeability value of the Asbuton material.

  3. Dams and river dolphins: Can they co-exist?

    International Nuclear Information System (INIS)

    Reeves, R.R.; Leatherwood, S.

    1994-01-01

    Dam construction is one of many ways that humans have modified river-dolphin habitats. It is suggested that physiographic and hydrologic complexity plays an important role in making rivers suitable for dolphins. If this hypothesis is true, then it can be assumed that dams and other artificial obstructions degrade dolphin habitat insofar as they reduce such complexity. This paper identifies some of the impacts that dams, barrages, and dikes might have on dolphins. Research is needed at project sites, both before and after construction, to document impacts. Specially designed ''swimways'' may allow upstream and downstream passage by dolphins and thus mitigate at least one of the adverse effects of dam projects, namely population fragmentation, but such measures aimed at benefiting single species are no substitute for protecting ecosystems. 30 refs

  4. Short-rotation cultivation of fast-growing willows and plantations of Betula pendula, Roth on Hirvineva, a mire formerly used for peat production, in Liminka, Finland. Nopeakasvuisten pajujen (Salix spp. ) lyhytkiertoviljelystae ja rauduskoivun (Betula pendula) viljelystae turvetuotannosta poistuneella suolla, limingan Hirvinevalla

    Energy Technology Data Exchange (ETDEWEB)

    Lumme, I.; Kiukaanniemi, E.

    1987-01-01

    This report is concerned with afforestation experiments using fast-growing willows (Salix spp.) and silver birch (Betula pendula, Roth) conducted by the Northern Finland Research Institute of the University of Oulu at the site of a mire formerly used for peat production, Hirvineva in the commune of Liminka (62 deg C 45{sup '} N, 23 deg C 30{sup '} E). Experiments were carried out at the early stages of willow cultivation into the use of chemical fertilizers and peat ash, the liming requirement of the soil and the effects of tilling of the soil on growth. Since 1985 efforts have been concentrated on developing new willow clones. Research was also begun into the mycorhiza which develop when willows are cultivated on peat soils. The experiments with Betula pendula were devoted to examining the effects of plantation density and fertilization with peat ash on four-year old saplings.

  5. Dynamic probability evaluation of safety levels of earth-rockfill dams using Bayesian approach

    Directory of Open Access Journals (Sweden)

    Zi-wu Fan

    2009-06-01

    Full Text Available In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural characteristics of dams, it is quite difficult to predict the time-varying factors affecting their safety levels. It is not feasible to employ dynamic reliability indices to evaluate the actual safety levels of dams. Based on the relevant regulations for dam safety classification in China, a dynamic probability description of dam safety levels was developed. Using the Bayesian approach and effective information mining, as well as real-time information, this study achieved more rational evaluation and prediction of dam safety levels. With the Bayesian expression of discrete stochastic variables, the a priori probabilities of the dam safety levels determined by experts were combined with the likelihood probability of the real-time check information, and the probability information for the evaluation of dam safety levels was renewed. The probability index was then applied to dam rehabilitation decision-making. This method helps reduce the difficulty and uncertainty of the evaluation of dam safety levels and complies with the current safe decision-making regulations for dams in China. It also enhances the application of current risk analysis methods for dam safety levels.

  6. Vegetation and flora of short-rotation willow stands from a conservation viewpoint

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, L.

    1986-01-01

    The energy forests were studied using random 0.5 x 0.5 m quadrats in which cover for field- and bottom-layer species was recorded in a percentage scale. The data were analysed using various multivariate methods. The vegetation and flora of twelve coppices in southern Sweden were investigated. Also the succession during the establishment phase on a meadow on the west coast and on a peat bog in the east-central part of the country was studied. Moreover, the impact on fen vegetation downstream of an energy forest on a peat bog was investigated. The flora and vegetation of energy forests is dominated by common ruderal species like Cirsium arvense, Galeopsis tetrahit and Urtica dioica. Uncommon species from woodland and fen habitats are only occasionally found. The field layer of energy forests shows a clear seasonality with maximal cover in July. The species number and the composition of vegetation vary greatly between the coppices and is largely determined by the management system. Intense cultivation including fertilization and the use of herbicides depletes the flora. Long rotation times decrease both species diversity and the field-layer cover. Uncommon species are mostly found in old coppices, which also often have a rich spring flora. A change in flora and vegetation occurs when an energy forest is established. The change is great and the time needed for stabilization of the energy forest flora is long when the original flora is dissimilar to the coppice flora. Willow coppices can increase habitat diversity in regions dominated by coniferous forests or in large-scale agricultural areas. Structural heterogeneity of a stand promotes diversity of the flora. Such heterogeneity can be created if a stand is composed of a variety of willow clones, if it is harvested at intervals, contains gaps, open ditches and is surrounded by edge zones of various types.

  7. Evidence of deepwater spawning of fall chinook salmon (Oncorhynchus tshawytscha): spawning near Ives and Pierce Island of the Columbia River, 1999; ANNUAL

    International Nuclear Information System (INIS)

    Mueller, Robert P.; Dauble, Dennis D.

    2000-01-01

    Fall chinook salmon Oncorhynchus tshawytscha, thought to originate from Bonneville Hatchery, were first noted to be spawning downstream of Bonneville Dam by Washington Department of Fisheries and Wildlife (WDFW) biologists in 1993 (Hymer 1997). Known spawning areas include gravel beds on the Washington side of the river near Hamilton Creek and Ives island. Limited spawning ground surveys were conducted in the area around Ives and Pierce Islands during 1994-1997 and based on these surveys it was believed that fall chinook salmon successfully spawned in this area. The size of this population from 1994 to 1996 was estimated at 1,800 to 5,200 fish (Hymer 1997). Recently, chum salmon were also documented spawning downstream of Bonneville Dam. Chum salmon O. kisutch were listed as threatened under the Endangered Species Act (ESA) in March, 1999. There are several ongoing investigations to define the physical habitat characteristics associated with fall chinook and chum salmon spawning areas downstream of Bonneville Dam. A major concern is to determine what flows (i.e. surface elevations) are necessary to ensure their long-term survival. Our objective was to locate deepwater spawning locations in the main Columbia River channel and to collect additional data on physical habitat parameters at the site. This objective is consistent with the high priority that the Northwest Power Planning Council's Independent Advisory Board and the salmon managers have placed on determining the importance of mainstem habitats to the production of salmon in the Columbia River Basin

  8. Mechanism Research of Arch Dam Abutment Forces during Overload

    Directory of Open Access Journals (Sweden)

    Yu Xia

    2015-01-01

    Full Text Available This paper presents research on the abutment forces of a double-curvature arch dam during overload based on numerical calculation results obtained through finite element method by Ansys. Results show that, with an increase in elevation, the abutment forces and bending moment of the arch dam increase first and then decrease from the bottom to the top of the dam. Abutment forces and bending moment reach their maximum at the middle or middle-down portion of the dam. The distributions of abutment forces and moment do not change during overload. The magnitude of each arch layer’s forces and moment increases linearly during overload. This result indicates that each arch layer transmits bearing loads to the rocks of the left and right banks steadily. This research explains the operating mechanism of an arch dam under normal and overload conditions. It provides a simple method to calculate the distribution of forces Fx and Fy and a new method to calculate the overload factor of an arch dam through the estimation of arch layers based on the redistribution characteristic of arch abutment forces.

  9. Determining The Water Quality of Maruf Dam (Boyabat–Sinop

    Directory of Open Access Journals (Sweden)

    Ekrem MUTLU

    2017-06-01

    Full Text Available In this study, the preliminary findings obtained from 3 sampling points, which represent the whole, on Maruf Irrigation Dam, which is located in Boyabat district of Sinop province, for 12 months between September 2015 and August 2016 were examined. The parameters monitored are temperature, dissolved oxygen, pH, electrical conductivity, total hardness, total alkalinity, chemical oxygen demand, biological oxygen demand, and dissolved anions and cations (sodium, potassium, calcium, magnesium, ammonium, nitrate, phosphate, chloride, sulfate, and sulfite. Because of its low dissolved ionic matter content, Maruf Dam was characterized as an alkali dam with mid-hard water and low electrical conductivity. In terms of parameters A and B of Surface Water Quality Management Regulation, the dam is considered “high-quality” and “unpolluted”. Besides the irrigation purposes, for which the barrage was constructed, the dam can also be used for aquaculture, animal breeding, and farming needs.

  10. Water resources of the Prairie Island Indian Reservation, Minnesota, 1994-97

    Science.gov (United States)

    Cowdery, Timothy K.

    1999-01-01

    This evaluation of the water resources on the Prairie Island Indian Reservation includes data collected from 8 surface-water sites and 22 wells during 1994–97 and historical data. The Mississippi River and the lakes and wetlands connected to it are separated from the Vermillion River and the lakes and wetlands connected to it by the surficial aquifer on Prairie Island and by Lock and Dam Number 3. These surface-water groups form hydrologic boundaries of the surficial aquifer. The aquifer is 130–200 feet thick, extends to bedrock (the Franconia Formation, which is also an aquifer), and is composed primarily of sand and gravel, but also contains thin, isolated lenses of finer-grained material. Flow in the surficial aquifer is normally from the Mississippi River to the Vermillion River (southwest). During spring snowmelt or heavy rains, a ground-water mound forms in the center of the study area and causes radial ground-water flow toward the surrounding surface waters.

  11. MNR's role in public safety around dams

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, Jennifer [Ministry of Natural Resources, Peterborough, ON (Canada)

    2011-07-01

    The Ministry of Natural Resources (MNR) is the largest dam owner in Ontario with around 400 dams located all across the province. MNR works to exercise stewardship of Ontario's water resources in a context of public safety, employee safety and environmental awarenes. This presentation shows the different measures MNR implemented to reduce risks. Warning signs, safety booms, barrel buoys and pedestrian fencing have been installed around dams to alert the public to possible dangers. In addition, MNR employees receive training in how to inspect dams for safety concerns, how to identify problems which could result in hazards to the public and how to work safely.

  12. Detection of Water Leaks in Beni-Haroun Dam (Algeria)

    International Nuclear Information System (INIS)

    Hocini, N.; Mami, M.

    2011-01-01

    The main objective of this work was to detect water leakage origin combining conventional, tracing and isotope techniques. The investigation was performed by a research team from the 'Algiers Nuclear Research Centre' in collaboration with engineers from the 'National Agency for Dams'. The chemical and isotopic results have shown no influence of dam water on the water sampled at the piezometers and drains that are present in the close neighbourhood of the dam. However, the water flowing at drain D15 has exhibited the nearest quality to that dam. Dye tracing has shown a water circulation through complex pathways for the left bank. (author)

  13. 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....

  14. User's Guide: Arch Dam Stress Analysis System (ADSAS)

    National Research Council Canada - National Science Library

    1997-01-01

    .... ADSAS assumes linear elastic behavior for the entire dam, i.e. the dam is assumed to support the computed tensile stresses within the concrete mass and across the monolith joints without cracking or opening the joints...

  15. Dams. Bulletin of the Technical Service of Electric Power and Big Dams; Barrages. Bulletin du Service Technique de l`Energie Electrique et des Grands Barrages

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    Four papers were selected in this issue of the bulletin of the Technical Service of Electric Power and Big Dams. The first one concerns the `Catastrophe Medicine` congress which took place in Amiens (France) in December 5 to 7 1996 and during which the analysis of experience feedbacks and lessons gained after dam accidents and organisation of emergency plans was discussed. The second one is a report of the conclusions of the decennial and annual inspections of French dams. The third paper describes the reinforcement of the Lavaud-Gelade dam embankment and the last paper reports on the Control Services activities concerning the French dams in operation for the forth quarter of the year 1996. (J.S.)

  16. Risk Perception Analysis Related To Existing Dams In Italy

    Science.gov (United States)

    Solimene, Pellegrino

    2013-04-01

    In the first part of this work, the progress of Italian National Rules about dams design, construction and operation are presented to highlight the strong connection existing between the promulgation of new decrees, as a consequence of a dam accidents, and the necessity to prevent further loss of lives and goods downstream. Following the Gleno Dam failure (1923), a special Ministerial Committee wrote out the first Regulations and made the proposal to establish, within the High Council of Public Works, a special department that become soon the "Dam Service", with the tasks of control and supervision about construction and operation phases of the dams and their reservoirs. A different definition of tasks and the structure of Dam Service were provided in accordance with law n° 183/1989, which transferred all the technical services to the Office of the Prime Minister; the aim was to join the Dam Office with the Department for National Technical Services, with the objective of increasing the knowledge of the territory and promoting the study on flood propagation downstream in case of operations on bottom outlet or hypothetical dam-break. In fact, population living downstream is not ready to accept any amount of risk because has not a good knowledge of the efforts of experts involved in dam safety, both from the operators and from the safety Authority. So it's important to optimize all the activities usually performed in a dam safety program and improve the emergency planning as a response to people's primary needs and feeling about safety from Civil Protection Authority. In the second part of the work, a definition of risk is provided as the relationship existing between probability of occurrence and loss, setting out the range within to plan for prevention (risk mitigation), thanks to the qualitative assessment of the minimum safety level that is suited to assign funds to plan for Civil Protection (loss mitigation). The basic meaning of the reliability of a zoned

  17. Dam safety review using non-destructive methods for reinforced concrete structure

    Energy Technology Data Exchange (ETDEWEB)

    Philibert, Alain; Saint-Pierre, Francois; Turcotte, Bernard [Le Groupe S.M. International Inc., Sherbrooke, (Canada)

    2010-07-01

    Dams built at the beginning of the twentieth century include concrete structures that were put in under rehabilitation works. In some cases, the details of the structures are not well documented. In other cases, concrete damage can be hidden under new layers of undamaged material. This requires that the dam safety review in a real investigation gather the information necessary for carrying out the hydraulic and stability studies required by the Dam Safety Act. This paper presented the process of dam safety review using non-destructive methods for reinforced concrete structures. Two reinforced concrete dams built in the 1900's, the Eustic dam on the Coaticook River and the Frontenac dam on the Magog River near Sherbrooke, were evaluated by S.M. International using non-destructive methods such as sonic and ground penetrating radar methods. The studies allowed mapping of concrete damage and provided geometric information on some non visible structure elements that were part of previous reinforcement operations.

  18. How to manage the cumulative flood safety of catchment dams ...

    African Journals Online (AJOL)

    Dam safety is a significant issue being taken seriously worldwide. However, in Australia, although much attention is being devoted to the medium- to large-scale dams, minimal attention is being paid to the serious potential problems associated with smaller dams, particularly the potential cumulative safety threats they pose ...

  19. Priority ranking for maintenance activities on embankment dams

    International Nuclear Information System (INIS)

    Chouinard, L.E.; Andersen, G.R.; Robichaud, J.G.; Blanchette, G.; Gervais, R.

    1998-01-01

    Operators of dams in Canada and the U.S. are steadily shifting from construction of new facilities to the maintenance and repairs of existing ones. This paper emphasized the importance of prioritizing maintenance activities on embankment dams whose maintenance needs vary from structure to structure. Two parallel procedures were developed, one for monitoring devices and the other for defense groups. Both procedures are intended to be used together to rate the condition of the embankment dams. The term 'defense groups' is used to refer to the collection of physical components on dams to prevent adverse conditions from occurring that would result in an uncontrolled release of the reservoir. The priority rankings and condition indices developed by means of this procedure reflects the judgment of a panel of engineers and geologists who implement them. They are not to be interpreted as an index of dam safety. While the process is sufficiently well developed to warrant wide-spread distribution, it is considered to be still in the developmental stage. Therefore, it should be used in conjunction with other parallel processes evaluating structural, mechanical and electrical features of the structure under consideration. 6 refs., 7 tabs

  20. Cleveland Dam East Abutment : seepage control project

    Energy Technology Data Exchange (ETDEWEB)

    Huber, F.; Siu, D. [Greater Vancouver Regional District, Burnaby, BC (Canada); Ahlfield, S.; Singh, N. [Klohn Crippen Consultants Ltd., Vancouver, BC (Canada)

    2004-09-01

    North Vancouver's 91 meter high Cleveland Dam was built in the 1950s in a deep bedrock canyon to provide a reservoir for potable water to 18 municipalities. Flow in the concrete gravity dam is controlled by a gated spillway, 2 mid-level outlets and intakes and 2 low-level outlets. This paper describes the seepage control measures that were taken at the time of construction as well as the additional measures that were taken post construction to control piezometric levels, seepage and piping and slope instability in the East Abutment. At the time of construction, a till blanket was used to cover the upstream reservoir slope for 200 meters upstream of the dam. A single line grout curtain was used through the overburden from ground surface to bedrock for a distance of 166 meters from the dam to the East Abutment. Since construction, the safety of the dam has been compromised through changes in piezometric pressure, seepage and soil loss. Klohn Crippen Consultants designed a unique seepage control measure to address the instability risk. The project involved excavating 300,000 cubic meters of soil to form a stable slope and construction bench. A vertical wall was constructed to block seepage. The existing seepage control blanket was also extended by 260 meters. The social, environmental and technical issues that were encountered during the rehabilitation project are also discussed. The blanket extension construction has met design requirements and the abutment materials that are most susceptible to internal erosion have been covered by non-erodible blanket materials such as plastic and roller-compacted concrete (RCC). The project was completed on schedule and within budget and has greatly improved the long-term stability of the dam and public safety. 2 refs., 8 figs.

  1. Descriptive characteristics of the large Italian dams

    International Nuclear Information System (INIS)

    Dello Vicario, E.; Petaccia, A.; Savanella, V.

    1999-01-01

    In the present note the characteristics of the Italian dams are examined, underlining, in a statistical view, story, geographical location, types and use of the most important works. Such a review can be useful for a more detailed analysis, both for the dams characterization and for further studies relevant to water resources utilization [it

  2. Primary Productivity of the Cengklik Dam Boyolali

    Directory of Open Access Journals (Sweden)

    WIRYANTO

    2002-01-01

    Full Text Available Primary productivity dynamic of the water ecosystem was conducted faster in the last decades. This study was intended to find out the primary productivity of Cengklik dam Boyolali, Central Java to explain the ecosystem dynamic and to lead the maintenance of dam. This study used quantitative methods in completely randomized group design (CRD, and the data was analized by Analysis of Variance (ANAVA. Samples were taken horizontally in four sampling point, respectively in the riparian zone, around of the floating net (“karamba”, in the center of dam water and around of the ex-paddy fields. There were taken vertically in three-depth point in each of the sampling point, respectively 0.5 meter, 1.5 meter, and 2.5 meter. The results showed that the gross primary productivity of the dam was 11.122.500-22.545.600 mgC/m3/days, and the primary productivity differences in each of the point sampling caused by light intensity, nutrient supply, and abundance of the chlorophyll organisms.

  3. Management of agro-pastoral dams in Benin: stakeholders, institutions and rehabilitation research

    NARCIS (Netherlands)

    Kpéra, G.N.; Aarts, N.; Saïdou, A.; Tossou, R.C.; Eilers, C.H.A.M.; Mensah, G.A.; Sinsin, B.A.; Kossou, D.K.; van der Zijpp, A.J.

    2012-01-01

    Agro-pastoral dams are waterholes constructed to provide water for livestock and for agricultural development. In Benin, agro-pastoral dams are managed by dam management committees. This study seeks to (1) characterize the stakeholders involved in agro-pastoral dam use and management, (2) identify

  4. Fragmentation of Andes-to-Amazon connectivity by hydropower dams.

    Science.gov (United States)

    Anderson, Elizabeth P; Jenkins, Clinton N; Heilpern, Sebastian; Maldonado-Ocampo, Javier A; Carvajal-Vallejos, Fernando M; Encalada, Andrea C; Rivadeneira, Juan Francisco; Hidalgo, Max; Cañas, Carlos M; Ortega, Hernan; Salcedo, Norma; Maldonado, Mabel; Tedesco, Pablo A

    2018-01-01

    Andes-to-Amazon river connectivity controls numerous natural and human systems in the greater Amazon. However, it is being rapidly altered by a wave of new hydropower development, the impacts of which have been previously underestimated. We document 142 dams existing or under construction and 160 proposed dams for rivers draining the Andean headwaters of the Amazon. Existing dams have fragmented the tributary networks of six of eight major Andean Amazon river basins. Proposed dams could result in significant losses in river connectivity in river mainstems of five of eight major systems-the Napo, Marañón, Ucayali, Beni, and Mamoré. With a newly reported 671 freshwater fish species inhabiting the Andean headwaters of the Amazon (>500 m), dams threaten previously unrecognized biodiversity, particularly among endemic and migratory species. Because Andean rivers contribute most of the sediment in the mainstem Amazon, losses in river connectivity translate to drastic alteration of river channel and floodplain geomorphology and associated ecosystem services.

  5. SCENARIO OF AN ACCIDENT OF SOIL DAMS IN CASE OF WATER SPILL OVER A DAM CREST BY USING FAULT TREE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Kuznetsov Dmitriy Viktorovich

    2016-04-01

    Full Text Available The scenario of a hydrodynamic accident of water flow over a crest of a soil dam is considered by the method of fault tree analysis, for which the basic reasons and controlled diagnostic indicators of an accident have been defined. Logical operators “AND”/”OR” were used for creation of a sequence of logically connected events, leading to an undesired event in the scenario of accident. The scenario of the accident was plotted in case of three basic reasons - an excessive settling of a dam crest, an excess flood, an inoperable spillway, taking into account the sequence of the events’ development and with observance of the necessary conditions leading to an accident. “Technical” reasons were observed in the present scenario, force majeure events were not considered. The provided scenario of the accident consists of two branches of events’ development: the left one that depends on an upstream level, and the right one that depends on settling of a dam crest. In each of the considered events an accident “the water spill over a crest of a soil dam” is possible only in case of execution of two different conditions at the same time, i.e. in case of an appropriate upstream level and the appropriate mark of a crest of a soil dam. The conditions of the accident are defined by diagnostic indices - the upstream level and settling of a dam crest, which at the same time are safety criteria of the hydraulic structure for soil dams. They allow defining the technical condition of the construction. Four possible technical conditions are suggested for the definition of technical statuses - normative, operable, limited operable, abnormal. Criteria of safety are the boundaries of the state: for loading and impact - it is the upstream level, for geometrical compliance of the construction - it is a dam crest mark.

  6. Hydroponic screening for metal resistance and accumulation of cadmium and zinc in twenty clones of willows and poplars

    International Nuclear Information System (INIS)

    Santos Utmazian, Maria Noel dos; Wieshammer, Gerlinde; Vega, Rosa; Wenzel, Walter W.

    2007-01-01

    We screened 20 different clones of willow and poplar species in hydroponic experiments for their metal resistance and accumulation properties. Plants were exposed for 4 weeks either to single additions of (μM) 4.45 Cd or 76.5 Zn, or a metal cocktail containing the same amounts of Cd and Zn along with 7.87 Cu and 24.1 Pb. Plant biomass, metal tolerance and metal accumulation pattern in roots and leaves varied greatly between clones. The leaf:root ratio of metal concentrations was clearly underestimated compared to soil experiments. The largest metal concentrations in leaves were detected in Salix dasyclados (315 mg Cd kg -1 d.m.) and a Salix smithiana clone (3180 mg Zn kg -1 d.m.) but these species showed low metal tolerance. In spite of smaller Cd and Zn concentrations, the metal-tolerant clones Salix matsudana, Salix fragilis-1, and Salix purpurea-1 hold promise for phytoextraction as they produced large biomass and metal contents in leaves. - Hydroponically grown willows and poplar clones accumulate up to (mg kg -1 d.w.) 315 Cd and 3180 Zn in leaves

  7. Hydroponic screening for metal resistance and accumulation of cadmium and zinc in twenty clones of willows and poplars

    Energy Technology Data Exchange (ETDEWEB)

    Santos Utmazian, Maria Noel dos [Department of Forest- and Soil Sciences, University of Natural Resources and Applied Life Sciences, Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna (Austria); Wieshammer, Gerlinde [Department of Forest- and Soil Sciences, University of Natural Resources and Applied Life Sciences, Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna (Austria); Vega, Rosa [Department of Forest- and Soil Sciences, University of Natural Resources and Applied Life Sciences, Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna (Austria); Wenzel, Walter W. [Department of Forest- and Soil Sciences, University of Natural Resources and Applied Life Sciences, Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna (Austria)]. E-mail: walter.wenzel@boku.ac.at

    2007-07-15

    We screened 20 different clones of willow and poplar species in hydroponic experiments for their metal resistance and accumulation properties. Plants were exposed for 4 weeks either to single additions of ({mu}M) 4.45 Cd or 76.5 Zn, or a metal cocktail containing the same amounts of Cd and Zn along with 7.87 Cu and 24.1 Pb. Plant biomass, metal tolerance and metal accumulation pattern in roots and leaves varied greatly between clones. The leaf:root ratio of metal concentrations was clearly underestimated compared to soil experiments. The largest metal concentrations in leaves were detected in Salix dasyclados (315 mg Cd kg{sup -1} d.m.) and a Salix smithiana clone (3180 mg Zn kg{sup -1} d.m.) but these species showed low metal tolerance. In spite of smaller Cd and Zn concentrations, the metal-tolerant clones Salix matsudana, Salix fragilis-1, and Salix purpurea-1 hold promise for phytoextraction as they produced large biomass and metal contents in leaves. - Hydroponically grown willows and poplar clones accumulate up to (mg kg{sup -1} d.w.) 315 Cd and 3180 Zn in leaves.

  8. National Dam Safety Program. Clove Lake Dam (NJ 00259) Delaware River Basin, Shimers Brook, Sussex County, New Jersey. Phase I Inspection Report.

    Science.gov (United States)

    1981-08-01

    it be reclassified as low hazard. The spillway will pass the 100-year flood and is considered adequate. e. Ownership. The dam is owned by Clubhouse ...Associates. For information, contact Mr. Gerald Roby, Clubhouse Associates, RD 4, Box 108, Montague, New Jersey 07827. f. Purpose. The Clove Lake Dam...into what appears to be a man-made lake downstream of Clove Lake Dam about 0.5 mile. Although no homes are presently constructed around this downstream

  9. Incremental Dynamic Analysis of Koyna Dam under Repeated Ground Motions

    Science.gov (United States)

    Zainab Nik Azizan, Nik; Majid, Taksiah A.; Nazri, Fadzli Mohamed; Maity, Damodar; Abdullah, Junaidah

    2018-03-01

    This paper discovers the incremental dynamic analysis (IDA) of concrete gravity dam under single and repeated earthquake loadings to identify the limit state of the dam. Seven ground motions with horizontal and vertical direction as seismic input considered in the nonlinear dynamic analysis based on the real repeated earthquake in the worldwide. All the ground motions convert to respond spectrum and scaled according to the developed elastic respond spectrum in order to match the characteristic of the ground motion to the soil type. The scaled was depends on the fundamental period, T1 of the dam. The Koyna dam has been selected as a case study for the purpose of the analysis by assuming that no sliding and rigid foundation, has been estimated. IDA curves for Koyna dam developed for single and repeated ground motions and the performance level of the dam identifies. The IDA curve of repeated ground motion shown stiffer rather than single ground motion. The ultimate state displacement for a single event is 45.59mm and decreased to 39.33mm under repeated events which are decreased about 14%. This showed that the performance level of the dam based on seismic loadings depend on ground motion pattern.

  10. Large eruption-triggered ocean-island landslide at Tenerife

    DEFF Research Database (Denmark)

    Harris, P; Branney, M; Storey, Michael

    2011-01-01

    An extensive debris-avalanche deposit has been discovered on Cañadas volcano, Tenerife (Canary Islands). The onshore component of the 733 ± 3 ka Abona landslide deposit exposes classic block facies and mixed facies across 90 km2. Three lines of evidence together show that the avalanche was trigge......An extensive debris-avalanche deposit has been discovered on Cañadas volcano, Tenerife (Canary Islands). The onshore component of the 733 ± 3 ka Abona landslide deposit exposes classic block facies and mixed facies across 90 km2. Three lines of evidence together show that the avalanche...... was triggered by an ignimbrite-forming explosive eruption: (1) the deposit is enclosed by phonolitic ignimbrites and is draped by a Plinian fallout layer, all within a single eruption unit; (2) it contains prismatic-jointed pumice blocks that were hot during landslide emplacement, indicated by chilled rims...... and breadcrust surfaces; (3) these blocks yield the same 40Ar/39Ar date as the associated ignimbrite and fall deposit. Landslide hummocks dammed surface water, forming ephemeral lakes perched on the volcano flank. Phonolite dome growth destabilized the southeast sector of a mid-Pleistocene Cañadas caldera wall...

  11. The effect of water availability on stand-level productivity, transpiration, water use efficiency and radiation use efficiency of field-grown willow clones

    DEFF Research Database (Denmark)

    Linderson, Maj-Lena; Iritz, Z.; Lindroth, A.

    2007-01-01

    The effect of water availability on stand-level productivity, transpiration, water use efficiency (WUE) and radiation use efficiency (RUE) is evaluated for different willow clones at stand level. The measurements were made during the growing season 2000 in a 3-year-old plantation in Scania......, southernmost Sweden. Six willow clones were included in the study: L78183, SW Rapp, SW Jorunn, SW Jorr, SW Tora and SW Loden. All clones were exposed to two water treatments: rain-fed, non-irrigated treatment and reduced water availability by reduced soil water recharge. Field measurements of stem sap...... low compared to other results. Generally, all clones, except for Jorunn, seem to be better off concerning biomass production, WUE and RUE than the reference clone. Jorr, Jorunn and Loden also seem to be able to cope with the reduced water availability with increase in the water use efficiency. Tora...

  12. COMPREHENSIVE ANALYSIS ON SEEPAGE AND STRUCTURAL STABILITY OF EARTH-ROCK DAM: A CASE STUDY OF XIQUANYAN DAM IN CHINA

    Directory of Open Access Journals (Sweden)

    Qingqing GUO

    2016-07-01

    Full Text Available Earth-rock dam is commonly used in the high-dam engineering around the world. It has been widely accepted that the analysis on structural and seepage stability plays a very important role, and it is necessary to take into account while designing the earth-rock dam. In performing the analysis of structural and seepage stability, many remarkable methods are available at current stage. However, there are still some important issues remaining unsolved, including: (1 Finite element methods (FEMs is a means of solutions to analysis seepage process, but it is often a difficult task to determine the so-called seepage coefficient, because the common-used water injection test is limited in the practical work due to the high cost and complex procedure. (2 It has long been discussed that the key parameters for structural stability analysis show a significant spatial and temporal variations. It may be partly explained by the inhomogeneous dam-filling during construction work and the developing seepage process. The consequence is that one constant value of the parameter cannot represent the above variations. In this context, we solve the above issues and introduce the solution with a practical earth-rock dam project. For determining the seepage coefficient, the data from the piezo metric tube is used to calculate the potential value, based on which the seepage coefficient can be back-analysed. Then the seepage field, as well as the seepage stability are numerically analysed using the FEM-based SEEP/W program. As to the structural safety, we take into account the spatial and temporal variations of the key parameters, and incorporate the Monte-Carlo simulation method into the commonly used M-P method to calculate the frequency distribution of the obtained structural safety factor. In this way, the structural and seepage safety can be well analysed. This study is also beneficial to provide a mature method and a theoretical insight into the earth-rock dam design

  13. FULCRUM - A dam safety management and alert system

    Energy Technology Data Exchange (ETDEWEB)

    Butt, Cameron; Greenaway, Graham [Knight Piesold Ltd., Vancouver, (Canada)

    2010-07-01

    Efficient management of instrumentation, monitoring and inspection data are the keys to safe performance and dam structure stability. This paper presented a data management system, FULCRUM, developed for dam safety management. FULCRUM is a secure web-based data management system which simplifies the process of data collection, processing and analysis of the information. The system was designed to organize and coordinate dam safety management requirements. Geotechnical instrumentation such as piezometers or inclinometers and operating data can be added to the database. Data from routine surveillance and engineering inspection can also be incorporated into the database. The system provides users with immediate access to historical and recent data. The integration of a GIS system allows for rapid assessment of the project site. Customisable alerting protocols can be set to identify and respond quickly to significant changes in operating conditions and potential impacts on dam safety.

  14. The behaviour of a large dam at severe frost

    Directory of Open Access Journals (Sweden)

    M. C. SPADEA

    1972-06-01

    Full Text Available Synthesizing the problem, the action of the thrusts in the
    behaviour of t h e dam of Pieve di Cadore, makes itself conspicuous expecially
    during three periods of the year:
    1. - About the end of June, the air temperature, 011 t h e average, overcomes
    the water one in the watershed upstream the dam: the bending of
    t h e dam upstream increases from the bottom to the top.
    2. - About the end of October, the thermal conditions change; the
    mean air temperature grows lower than the mean water temperature; the
    dam begins her bending dowstream.
    3. - When the air temperature is distinctly below 0 °C, the action of
    t h e t h r u s t s grows more complexe; t h e rocky waterlogged system downstream
    of t h e dam, while cooling, swells and pushes t h e bottom of t h e dam upstream;
    at t h e higher quote, on the contrary, the t h r u s t downstream continues.
    When the strenght limit of the medium is surpassed, arises a contrast
    between the rocky system and the concrete structure: this contrast can origin
    a t e very small fractures, revealed from seismic station installed into the
    central ashlar (XIV a t 660 metres height of t h e dam, under t h e form of microshocks
    which energy is of about 10I0-10U erg.

  15. The potential for dams to impact lowland meandering river floodplain geomorphology.

    Science.gov (United States)

    Marren, Philip M; Grove, James R; Webb, J Angus; Stewardson, Michael J

    2014-01-01

    The majority of the world's floodplains are dammed. Although some implications of dams for riverine ecology and for river channel morphology are well understood, there is less research on the impacts of dams on floodplain geomorphology. We review studies from dammed and undammed rivers and include influences on vertical and lateral accretion, meander migration and cutoff formation, avulsion, and interactions with floodplain vegetation. The results are synthesized into a conceptual model of the effects of dams on the major geomorphic influences on floodplain development. This model is used to assess the likely consequences of eight dam and flow regulation scenarios for floodplain geomorphology. Sediment starvation downstream of dams has perhaps the greatest potential to impact on floodplain development. Such effects will persist further downstream where tributary sediment inputs are relatively low and there is minimal buffering by alluvial sediment stores. We can identify several ways in which floodplains might potentially be affected by dams, with varying degrees of confidence, including a distinction between passive impacts (floodplain disconnection) and active impacts (changes in geomorphological processes and functioning). These active processes are likely to have more serious implications for floodplain function and emphasize both the need for future research and the need for an "environmental sediment regime" to operate alongside environmental flows.

  16. The Potential for Dams to Impact Lowland Meandering River Floodplain Geomorphology

    Directory of Open Access Journals (Sweden)

    Philip M. Marren

    2014-01-01

    Full Text Available The majority of the world's floodplains are dammed. Although some implications of dams for riverine ecology and for river channel morphology are well understood, there is less research on the impacts of dams on floodplain geomorphology. We review studies from dammed and undammed rivers and include influences on vertical and lateral accretion, meander migration and cutoff formation, avulsion, and interactions with floodplain vegetation. The results are synthesized into a conceptual model of the effects of dams on the major geomorphic influences on floodplain development. This model is used to assess the likely consequences of eight dam and flow regulation scenarios for floodplain geomorphology. Sediment starvation downstream of dams has perhaps the greatest potential to impact on floodplain development. Such effects will persist further downstream where tributary sediment inputs are relatively low and there is minimal buffering by alluvial sediment stores. We can identify several ways in which floodplains might potentially be affected by dams, with varying degrees of confidence, including a distinction between passive impacts (floodplain disconnection and active impacts (changes in geomorphological processes and functioning. These active processes are likely to have more serious implications for floodplain function and emphasize both the need for future research and the need for an “environmental sediment regime” to operate alongside environmental flows.

  17. National Dam Safety Program. Potake Lake Dam (Inventory Number N.Y. 970), Passaic River Basin, Lower Hudson River Area, Rockland County, New York. Phase I Inspection Report,

    Science.gov (United States)

    1981-08-14

    facilitate thedischarge of storm flows. 2. The animal burrows, depressions , and tire ruts onthe crest of the dam should be filled, compacted and seeded. 3...storm flows. 2. The animal burrows, depressions , and tire ruts on the crest of the dam should be filled, compacted, and seeded...defined by the Recommended Guidelines for Safety Inspection of Dams (Reference 13, Appendix D). d. Hazard Classifications - Cranberry Lake Dam is one mile

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

    Science.gov (United States)

    Torres-Sierra, Heriberto; Gómez-Fragoso, Julieta

    2015-01-01

    The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, completed a hydrologic and hydraulic study to assess the potential hazard to human life and property associated with the hypothetical failure of the Lago de Matrullas Dam, located within the headwaters of the Río Grande de Manatí. The hydrologic study yielded outflow hydrographs and peak discharges for Lago de Matrullas and other subbasins in the Río Grande de Manatí hydrographic basin for three extreme rainfall events: (1) a 6-hour probable maximum precipitation (PMP) event, (2) a 24-hour PMP event, and (3) a 100-year-recurrence, 24-hour rainfall event. The hydraulic study simulated the hypothetical dam failure of Lago de Matrullas using hypothetical flood hydrographs generated from the hydrologic study and selected dam breach parameters. The flood wave resulting from the failure was downstream-routed through the lower reaches of the Río Matrullas, the Río Toro Negro, and the Río Grande de Manatí for determination of water-surface profiles developed from the event-based hydrologic scenarios and “sunny day” (no precipitation) conditions. The Hydrologic Modeling System (HEC–HMS) and the River Analysis System (HEC–RAS) computer programs, developed by the Hydrologic Engineering Center (HEC) of the U.S. Army Corps of Engineers, were used for the hydrologic and hydraulic modeling, respectively. The flow routing in the hydraulic analyses was performed using the unsteady-state flow module available in the HEC–RAS model.

  19. Impact of dam-building on marine life

    Science.gov (United States)

    Pandian, T. J.

    1980-03-01

    Dam-building across naturally flowing rivers tends to decrease discharge of surplus water into the sea, reduce nutrient concentration in estuaries and coastal waters, and diminish plankton blooms as well as fish landings. Depletion of nutrients and organic matter along with reduced mud and silt deposition affect benthic life on the continental shelf. Reduced mud and silt deposition leads to coastal retreat. Dams, especially those constructed for hydro-electric purposes, hinder migration of fishes and decapods. Discharge from dams can create barriers at high or low flows, cause delays, disrupt normal behavioural routine and change the travel speed of migratory animals. Where all spawners of a given population are frequently kept away from the breeding site, the population faces extinction.

  20. DESIGN OF SLIT DAMS FOR CONTROLLING STONY DEBRIS FLOWS

    Institute of Scientific and Technical Information of China (English)

    Hui-Pang LIEN

    2003-01-01

    A new method to a slit dam for controlling the stony debris flow has been derived based on the mass conservation law of the stony debris flow passing through a slit dam and the laboratory experiment results.This new method is then combined with three primary efficiency expressions: the dimensionless sediment outflow ratio,the sediment concentration ratio,and the sediment storage rate to develop a simple module,with which the height and the spacing of the posts,as well as the total spacing of slit dam are determined.Furthermore,these expressions can also be applied to check those slit dams that have already been constructed with their effectiveness against various magnitudes of the debris flow. The comparison between these expressions and laboratory data is in reasonable agreement.

  1. Putting Roman Dams in Context: a Virtual Approach

    Science.gov (United States)

    Decker, M. J.; Du Vernay, J. P.; Mcleod, J. B.

    2017-08-01

    Water resources and management have become a critical global issue. During the half-millennium of its existence, the Roman Empire developed numerous strategies to cope with water management, from large-scale urban aqueduct systems, to industrial-scale water mills designed to cope with feeding growing city populations. Roman engineers encountered, adopted, and adapted indigenous hydraulic systems, and left lasting imprints on the landscape of the Mediterranean and temperate Western Europe by employing a range of water technologies. A recent academic study has enabled the identification of remains of and references to seventy-two dams from the Roman era, constructed in Spain between the 1st and 4th century AD. Such unique heritage, without comparisons in the Mediterranean makes Spain an emblematic case study for the analysis of Roman hydraulic engineering and water management policies. Fifty dams have been located and detailed. The twenty-two outstanding, although identified on the ground, have not been able to be acceptably characterized, due in some cases to their being ruins in a highly degraded state, others due to their being masked by repairs and reconstructions subsequent to the Roman era. A good example of such neglected dams is the buttress dam of Consuegra , in Toledo province (Castilla-La Mancha). Dating to the 3rd - 4th century AD, the Dam of Consuegra, on the basin of the Guadiana, with its over 600 metres length and 4,80 metres height, is a remarkable case of Roman engineering mastery. It had a retaining wall upstream, numerous buttresses and perhaps an embankment downstream, of which no remains are left. The application of 3D digital imaging technique to create a high quality virtual model of such monuments has proved to be successful especially for the study of the technological aspects related its construction. The case study of the Roman dam of Muel (Zaragoza) has shown, in fact, as best practices in digital archaeology can provide an original and

  2. Importance of the 2014 Colorado River Delta pulse flow for migratory songbirds: Insights from foraging behavior

    Science.gov (United States)

    Darrah, Abigail J.; Greeney, Harold F.; van Riper, Charles

    2017-01-01

    The Lower Colorado River provides critical riparian areas in an otherwise arid region and is an important stopover site for migrating landbirds. In order to reverse ongoing habitat degradation due to drought and human-altered hydrology, a pulse flow was released from Morelos Dam in spring of 2014, which brought surface flow to dry stretches of the Colorado River in Mexico. To assess the potential effects of habitat modification resulting from the pulse flow, we used foraging behavior of spring migrants from past and current studies to assess the relative importance of different riparian habitats. We observed foraging birds in 2000 and 2014 at five riparian sites along the Lower Colorado River in Mexico to quantify prey attack rates, prey attack maneuvers, vegetation use patterns, and degree of preference for fully leafed-out or flowering plants. Prey attack rate was highest in mesquite (Prosopis spp.) in 2000 and in willow (Salix gooddingii) in 2014; correspondingly, migrants predominantly used mesquite in 2000 and willow in 2014 and showed a preference for willows in flower or fruit in 2014. Wilson’s warbler (Cardellina pusilla) used relatively more low-energy foraging maneuvers in willow than in tamarisk (Tamarix spp.) or mesquite. Those patterns in foraging behavior suggest native riparian vegetation, and especially willow, are important resources for spring migrants along the lower Colorado River. Willow is a relatively short-lived tree dependent on spring floods for dispersal and establishment and thus spring migrants are likely to benefit from controlled pulse flows.

  3. 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.

  4. Calculating earth dam seepage using HYDRUS software applications

    Directory of Open Access Journals (Sweden)

    Jakub Nieć

    2017-06-01

    Full Text Available This paper presents simulations of water seepage within and under the embankment dam of Lake Kowalskie reservoir. The aim of the study was to compare seepage calculation results obtained using analytical and numerical methods. In April 1985, after the first filling of the reservoir to normal storage levels, water leaks was observed at the base of the escarpment, on the air side of the dam. In order to control seepage flow, drainage was performed and additional piezometers installed. To explain the causes of increased pressure in the aquifer under the dam in May 1985 a simplified calculation of filtration was performed. Now, on the basis of archived data from the Department of Hydraulic and Sanitary Engineering using 3D HYDRUS STANDARD software, the conditions of seepage under the dam have been recreated and re-calculated. Piezometric pressure was investigated in three variants of drainage, including drainage before and after modernization.

  5. Safety management of the Karapiro dam, New Zealand

    International Nuclear Information System (INIS)

    Everitt, S.C.

    1995-01-01

    The dam safety program for 36 hydraulic structures in New Zealand were presented, with special emphasis on the application of this program to the Karapiro dam. The management of the hazard presented by the dam was detailed, and the proposed solutions for its remediation were presented. Dynamic analysis was employed using an elastic 3-D finite element model, using actual earthquake time history records as an input, scaled to the required Maximum Credibility Earthquake (MCE). The results confirmed that the arch section of the Karapiro dam was satisfactory, as was the spillway block, provided that drainage was preserved, however, the left abutment and thrust block were considered unstable. Four options were proposed for strengthening the abutment: (1) lowering the groundwater, (2) installation of stresses anchors, (3) mass concrete buttressing upstream and/or downstream, and (4) installation of reinforced concrete shear keys. However, prior to undertaking any remediation work, rock mass properties and groundwater conditions should be re-investigated. 1 ref., 7 figs

  6. Physical Modeling of Landslide Generated Tsunamis and the 50th Anniversary of the Vajont Dam Disaster

    Science.gov (United States)

    McFall, Brian C.; Mohammed, Fahad; Fritz, Hermann M.

    2013-04-01

    The Vajont river is an affluent of the Piave River located in the Dolomite Alps of the Veneto Region, about 100km north of Venice. A 265.5 m high double curved arch dam was built across a V-shaped gorge creating a reservoir with a maximum storage capacity of 0.169 km3. A maximum water depth of 250 m was reached by early September 1963 during the third filling attempt of the reservoir, but as creeping on the southern flank increased the third reservoir draw down was initiated. By October 9, 1963 the water depth was lowered to 240m as the southern flank of Vajont reservoir catastrophically collapsed on a length of more than 2km. Collapse occurred during reservoir drawdown in a final attempt to reduce flank creeping and the reservoir was only about two-thirds full. The partially submerged rockslide with a volume of 0.24 km3 penetrated into the reservoir at velocities up to 30 m/s. The wave runup in direct prolongation of slide axis reached the lowest houses of Casso 270m above reservoir level before impact corresponding to 245m above dam crest (Müller, 1964). The rockslide deposit came within 50m of the left abutment and towers up to 140m above the dam crest. The lateral spreading of the surge overtopped the dam crest by more than 100m. The thin arch dam withstood the overtopping and sustained no damage to the structural shell and the abutments. The flood wave dropped more than 500m down the Vajont gorge and into the Piave Valley causing utter destruction to the villages of Longarone, Pirago, Villanova, Rivalta and Fae. More than 2000 persons perished. The Vajont disaster highlights an extreme landslide tsunami event in the narrowly confined water body of a reservoir. Landslide tsunami hazards exist even in areas not exposed to tectonic tsunamis. Source and runup scenarios based on real world events are physically modeled in the three dimensional NEES tsunami wave basin (TWB) at Oregon State University (OSU). A novel pneumatic landslide tsunami generator (LTG) was

  7. Mapping the social impacts of small dams: The case of Thailand's Ing River basin.

    Science.gov (United States)

    Fung, Zali; Pomun, Teerapong; Charles, Katrina J; Kirchherr, Julian

    2018-05-24

    The social impacts of large dams have been studied extensively. However, small dams' social impacts have been largely neglected by the academic community. Our paper addresses this gap. We examine the social impacts of multiple small dams in one upstream and one downstream village in Thailand's Ing River basin. Our research is based on semi-structured interviews with beneficiaries, government and NGOs. We argue that small dams' social impacts are multi-faceted and unequal. The dams were perceived to reduce fish abundance and provide flood mitigation benefits. Furthermore, the dams enabled increased access to irrigation water for upstream farmers, who re-appropriated water via the dams at the expense of those downstream. The small dams thus engendered water allocation conflicts. Many scholars, practitioners and environmentalists argue that small dams are a benign alternative to large dams. However, the results of our research mandate caution regarding this claim.

  8. Feasibility of groundwater recharge dam projects in arid environments

    Science.gov (United States)

    Jaafar, H. H.

    2014-05-01

    A new method for determining feasibility and prioritizing investments for agricultural and domestic recharge dams in arid regions is developed and presented. The method is based on identifying the factors affecting the decision making process and evaluating these factors, followed by determining the indices in a GIS-aided environment. Evaluated parameters include results from field surveys and site visits, land cover and soils data, precipitation data, runoff data and modeling, number of beneficiaries, domestic irrigation demand, reservoir objectives, demography, reservoirs yield and reliability, dam structures, construction costs, and operation and maintenance costs. Results of a case study on more than eighty proposed dams indicate that assessment of reliability, annualized cost/demand satisfied and yield is crucial prior to investment decision making in arid areas. Irrigation demand is the major influencing parameter on yield and reliability of recharge dams, even when only 3 months of the demand were included. Reliability of the proposed reservoirs as related to their standardized size and net inflow was found to increase with increasing yield. High priority dams were less than 4% of the total, and less priority dams amounted to 23%, with the remaining found to be not feasible. The results of this methodology and its application has proved effective in guiding stakeholders for defining most favorable sites for preliminary and detailed design studies and commissioning.

  9. Evaluating the Invasion of Red Cedar (Juniperus viriginiana) Downstream of Gavins Point Dam, Missouri National Recreational River

    Science.gov (United States)

    Greene, S.; Knox, J. C.

    2013-12-01

    Gavins Point Dam, the final dam on the main-stem Missouri River, alters downstream river form and function. Throughout a 59-mile downstream reach, the dam reduces overbank flooding and lowers the water surface by 1-3 meters. Under the dam-created hydro-geomorphic conditions, native cottonwood trees are unable to regenerate. The limited regeneration of native riparian cottonwoods, the lowered water surface, and the reduced overbank flooding creates a terrace environment within the riparian habitat. Consequently, red cedars, a native upland tree, are invading this new terrace-like riparian environment. To this end, we apply Bayesian statistical models to investigate patterns of red cedar riparian invasion and assess ecosystem function patterns along this flow-regulated reach. We set up plots within cottonwood stands along a 59-km reach downstream of Gavins Point Dam. Within each plot, we collected soil samples, litter samples, stem densities of trees, and collected cores of the largest cottonwood and largest red cedar in each plot. To assess influences of red cedar on soil indicators of ecosystem function and general patterns of ecosystem function within the study area, we measured organic carbon, nitrogen, pH, electrical conductivity, and hydrophobicity. To determine drivers and patterns of invasion and ecosystem function we conducted Bayesian linear regressions and means comparison tests. Red cedars existed along the floodplain prior to regulation. However, according to our tree age data and stem density data red cedars existed at a lower population than today. We found that 2 out of 565 red cedars established before the dam was completed. Also, we found no significant difference in soil properties between soils with established red cedar and soils with established cottonwood. By studying soil texture data, and interpreting fluvial geomorphic surfaces in the field and via aerial photography, we found soil texture generally reflects the type of fluvial surface

  10. [The role of the floodplain gradient in structuring of testate amoebae communities in the Ilych River].

    Science.gov (United States)

    Mazeĭ, Iu A; Malysheva, E A; Lapteva, E M; Komarov, A A; Taskaeva, A A

    2012-01-01

    Forty-two testate amoebae taxa were identified in alluvial soils of floodplain islands in the Ilych River. Among the pedo- and eurybionts, there were aquatic rhizopods. Along the floodplain transect (willow --> meadow --> deciduous forest --> coniferous forest), the testate amoebae community changed directly. There are spatially homogeneous (low beta-diversity) testacean communities but species rich on the local level (high alpha-diversity) within forests. Within willows and meadows, communities are characterized by low alpha-diversity and high heterogeneity that leads to high gamma-diversity.

  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. Strategies of Successful Anti-Dam Movements: Evidence from Myanmar and Thailand

    NARCIS (Netherlands)

    Kirchherr, J.W.|info:eu-repo/dai/nl/411261487

    2018-01-01

    Scholars are rarely able to examine anti-dam movements that result in project suspensions or cancellations since these cases are rare empirically. Yet, they are central to understanding how anti-dam movements can succeed. This paper analyzes the movements against Myanmar’s Myitsone Dam and

  13. Evaluating temporal changes in hydraulic conductivities near karst-terrain dams: Dokan Dam (Kurdistan-Iraq)

    Science.gov (United States)

    Dafny, Elad; Tawfeeq, Kochar Jamal; Ghabraie, Kazem

    2015-10-01

    Dam sites provide an outstanding opportunity to explore dynamic changes in the groundwater flow regime because of the high hydraulic gradient rapidly induced in their surroundings. This paper investigates the temporal changes of the hydraulic conductivities of the rocks and engineered structures via a thorough analysis of hydrological data collected at the Dokam Dam, Iraq, and a numerical model that simulates the Darcian component of the seepage. Analysis of the data indicates increased seepage with time and suggests that the hydraulic conductivity of the rocks increased as the conductivity of the grout curtain decreased. Conductivity changes on the order of 10-8 m/s, in a 20-yr period were quantified using the numerical analysis. It is postulated that the changes in hydraulic properties in the vicinity of Dokan Dam are due to suspension of fine materials, interbedded in small fissures in the rocks, and re-settlement of these materials along the curtain. Consequently, the importance of the grout curtain to minimize the downstream seepage, not only as a result of the conductivity contrast with the rocks, but also as a barrier to suspended clay sediments, is demonstrated. The numerical analysis also helped us to estimate the proportion of the disconnected karstic conduit flow to the overall flow.

  14. Endocrine-disruptor molecular responses, occurrence of intersex and gonado-histopathological changes in tilapia species from a tropical freshwater dam (Awba Dam) in Ibadan, Nigeria

    International Nuclear Information System (INIS)

    Adeogun, Aina O.; Onibonoje, Kolawole; Ibor, Oju R.; Omiwole, Roseline A.; Chukwuka, Azubuike V.; Ugwumba, Alex O.; Ugwumba, Adiaha A.A.; Arukwe, Augustine

    2016-01-01

    Highlights: • Occurrence and severity of intersex in Nigerian aquatic environment. • Estrogenic and reproductive developmental effects of effluents from a University community. • Biomarker of endocrine disruption in fish from a developing country. • Relationship between estrogenic responses and sediment contaminants burden in a dam used for University domestic water supply and for fisheries. • Possible health consequences of environmental contamination - Abstract: In the present study, the occurrence of endocrine disruptive responses in Tilapia species from Awba Dam has been investigated, and compared to a reference site (Modete Dam). The Awba Dam is a recipient of effluents from University of Ibadan (Nigeria) and several other anthropogenic sources. A total of 132 Tilapia species (Sarotherodon malenotheron (n = 57 and 32, males and females, respectively) and Tilapia guineensis (n = 23 and 20, males and females, respectively)) were collected from June to September 2014. At the reference site, samples of adult male and female S. melanotheron (48 males and 47 females) and T. guineensis (84 males and 27 females) were collected. Gonads were morphologically and histologically examined and gonadosomatic index (GSI) was calculated. Hepatic mRNA transcriptions of vitellogenin (Vtg) and zona radiata protein (Zrp) genes were analyzed using validated RT-qPCR. Significant increase in Vtg and Zrp transcripts were observed in male tilapias from Awba Dam, compared to males from the reference site. In addition, male tilapias from Awba Dam produced significantly higher Vtg and Zrp mRNA, compared to females in June and July. However, at the natural peak spawning period in August and September, females produced, significantly higher Vtg and Zrp mRNA, compared to males. Fish gonads revealed varying incidence of intersex with a striking presence of two (2) pairs of testes and a pair of ovary in S. melanotheron from Awba Dam. The entire fish population examined at Awba Dam

  15. Endocrine-disruptor molecular responses, occurrence of intersex and gonado-histopathological changes in tilapia species from a tropical freshwater dam (Awba Dam) in Ibadan, Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Adeogun, Aina O.; Onibonoje, Kolawole; Ibor, Oju R.; Omiwole, Roseline A.; Chukwuka, Azubuike V.; Ugwumba, Alex O.; Ugwumba, Adiaha A.A. [Department of Zoology, University of Ibadan, Ibadan (Nigeria); Arukwe, Augustine, E-mail: arukwe@bio.ntnu.no [Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)

    2016-05-15

    Highlights: • Occurrence and severity of intersex in Nigerian aquatic environment. • Estrogenic and reproductive developmental effects of effluents from a University community. • Biomarker of endocrine disruption in fish from a developing country. • Relationship between estrogenic responses and sediment contaminants burden in a dam used for University domestic water supply and for fisheries. • Possible health consequences of environmental contamination - Abstract: In the present study, the occurrence of endocrine disruptive responses in Tilapia species from Awba Dam has been investigated, and compared to a reference site (Modete Dam). The Awba Dam is a recipient of effluents from University of Ibadan (Nigeria) and several other anthropogenic sources. A total of 132 Tilapia species (Sarotherodon malenotheron (n = 57 and 32, males and females, respectively) and Tilapia guineensis (n = 23 and 20, males and females, respectively)) were collected from June to September 2014. At the reference site, samples of adult male and female S. melanotheron (48 males and 47 females) and T. guineensis (84 males and 27 females) were collected. Gonads were morphologically and histologically examined and gonadosomatic index (GSI) was calculated. Hepatic mRNA transcriptions of vitellogenin (Vtg) and zona radiata protein (Zrp) genes were analyzed using validated RT-qPCR. Significant increase in Vtg and Zrp transcripts were observed in male tilapias from Awba Dam, compared to males from the reference site. In addition, male tilapias from Awba Dam produced significantly higher Vtg and Zrp mRNA, compared to females in June and July. However, at the natural peak spawning period in August and September, females produced, significantly higher Vtg and Zrp mRNA, compared to males. Fish gonads revealed varying incidence of intersex with a striking presence of two (2) pairs of testes and a pair of ovary in S. melanotheron from Awba Dam. The entire fish population examined at Awba Dam

  16. Application of the Periodic Average System Model in Dam Deformation Analysis

    Directory of Open Access Journals (Sweden)

    Yueqian Shen

    2015-01-01

    Full Text Available Dams are among the most important hydraulic engineering facilities used for water supply, flood control, and hydroelectric power. Monitoring of dams is crucial since deformation might have occurred. How to obtain the deformation information and then judge the safe conditions is the key and difficult problem in dam deformation monitoring field. This paper proposes the periodic average system model and creates the concept of “settlement activity” based on the dam deformation issue. Long-term deformation monitoring data is carried out in a pumped-storage power station, this model combined with settlement activity is used to make the single point deformation analysis, and then the whole settlement activity profile is drawn by clustering analysis. Considering the cumulative settlement value of every point, the dam deformation trend is analyzed in an intuitive effect way. The analysis mode of combined single point with multipoints is realized. The results show that the key deformation information of the dam can be easily grasped by the application of the periodic average system model combined with the distribution diagram of settlement activity. And, above all, the ideas of this research provide an effective method for dam deformation analysis.

  17. Optimization design of foundation excavation for Xiluodu super-high arch dam in China

    Directory of Open Access Journals (Sweden)

    Qixiang Fan

    2015-04-01

    Full Text Available With better understanding of the quality and physico-mechanical properties of rocks of dam foundation, and the physico-mechanical properties and structure design of arch dam in association with the foundation excavation of Xiluodu arch dam, the excavation optimization design was proposed for the foundation surface on the basis of feasibility study. Common analysis and numerical analysis results demonstrated the feasibility of using the weakly weathered rocks III1 and III2 as the foundation surface of super-high arch dam. In view of changes in the geological conditions at the dam foundation along the riverbed direction, the design of extending foundation surface excavation area and using consolidating grouting and optimizing structure of dam bottom was introduced, allowing for harmonization of the arch dam and foundation. Three-dimensional (3D geomechanics model test and finite element analysis results indicated that the dam body and foundation have good overload stability and high bearing capacity. The monitoring data showed that the behaviors of dam and foundation correspond with the designed patterns in the construction period and the initial operation period.

  18. A progressive methodology for seismic safety evaluation of gravity dams

    International Nuclear Information System (INIS)

    Ghrib, F.; Leger, P.; Tinawi, R.; Lupien, R.; Veilleux, M.

    1995-01-01

    A progressive methodology for the seismic safety evaluation of existing concrete gravity dams was described. The methodology was based on five structural analysis levels with increasing complexity to represent inertia forces, dam-foundation and dam-interaction mechanisms, as well as concrete cracking. The five levels were (1) preliminary screening, (2) pseudo-static method, (3) pseudo-dynamic method, (4) linear time history analysis, and (5) non-linear history analysis. The first four levels of analysis were applied for the seismic safety evaluation of Paugan gravity dam (Quebec). Results showed that internal forces from pseudo-dynamic, response spectra and transient finite element analyses could be used to interpret the dynamic stability of dams from familiar strength-based criteria. However, as soon as the base was cracked, the seismically induced forces were modified, and level IV analyses proved more suitable to handle rationally these complexities. 8 refs., 7 figs., 1 tab

  19. Dam-Break Flood Analysis Upper Hurricane Reservoir, Hartford, Vermont

    National Research Council Canada - National Science Library

    Acone, Scott

    1995-01-01

    .... Various dam break flood conditions were modeled and inundation maps developed. Based on this analysis the dam is rated a Class 2 or significant hazard category in terms of its potential to cause downstream damage...

  20. Review Article: Numerical analysis of the seismic behaviour of earth dam

    Directory of Open Access Journals (Sweden)

    Y. Parish

    2009-03-01

    Full Text Available The present study concerns analysis of the seismic response of earth dams. The behaviour of both the shell and core of the dam is described using the simple and popular non associated Mohr-Coulomb criterion. The use of this constitutive model is justified by the difficulty to obtain constitutive parameters for more advanced constitutive relations including isotropic and kinematic hardening. Analyses with real earthquake records show that the seismic loading induces plasticity in a large part of the shell and in the lower part of the core. Analysis shows that plasticity should be considered in the analysis of the seismic response of the dam, because it leads to a decrease in the natural frequencies of the dam together to energy dissipation, which could significantly affect the seismic response of the dam. Plastic analysis constitutes also a good tool for the verification of the stability of the dam under seismic loading.

  1. Potential Risk Analysis of Tailings Dam under Preloading Condition and Its Countermeasures

    Directory of Open Access Journals (Sweden)

    Shuren Wang

    2015-01-01

    Full Text Available It is very important for mine production safety to ensure the stability of the tailings dam. Taking a flatland tailings pond as the background, a threedimensional computational model was built based on a tailings dam under mullock heap preloading condition. Considering the current operating water level conditions, a liquid-solid coupling analysis of the model was conducted.The deformation characteristics of the tailings dam were revealed during successive preloading at the front of the dam. The safety factor and the potential slide face of the tailings dam were calculated under different conditions using the strength reduction method. The results show that the tailings dam in its current condition is basically stable, but if the mullock heap continues to be heightened, the tailings dam will become unstable. Therefore, in order to limit the height of the mullock heap, establishing a monitor and early warning mechanism are put forward to ensure mine production safety.

  2. Seismic rehabilitation and analysis of Chaohe earth dam

    Science.gov (United States)

    Fu, Lei; Zeng, Xiangwu

    2005-12-01

    Stability of earth dams during earthquakes has been a major concern for geotechnical engineers in seismic active regions. Liquefaction induced slope failure occurred at the upstream slope of a major earth dam in the suburb of Beijing, China, during the 1976 Tangshan Earthquake. The gravelly soil with loose initial condition liquefied under relatively small ground vibration. In recent years, a major seismic rehabilitation project was carried out on a similar earth dam nearby using dumped quarry stone. Seismic stability analysis was carried out using model test, finite element simulation, and pseudo-static slope stability program after taking into account the influence of excess pore pressure.

  3. 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...

  4. Endocrine-disruptor molecular responses, occurrence of intersex and gonado-histopathological changes in tilapia species from a tropical freshwater dam (Awba Dam) in Ibadan, Nigeria.

    Science.gov (United States)

    Adeogun, Aina O; Onibonoje, Kolawole; Ibor, Oju R; Omiwole, Roseline A; Chukwuka, Azubuike V; Ugwumba, Alex O; Ugwumba, Adiaha A A; Arukwe, Augustine

    2016-05-01

    In the present study, the occurrence of endocrine disruptive responses in Tilapia species from Awba Dam has been investigated, and compared to a reference site (Modete Dam). The Awba Dam is a recipient of effluents from University of Ibadan (Nigeria) and several other anthropogenic sources. A total of 132 Tilapia species (Sarotherodon malenotheron (n=57 and 32, males and females, respectively) and Tilapia guineensis (n=23 and 20, males and females, respectively)) were collected from June to September 2014. At the reference site, samples of adult male and female S. melanotheron (48 males and 47 females) and T. guineensis (84 males and 27 females) were collected. Gonads were morphologically and histologically examined and gonadosomatic index (GSI) was calculated. Hepatic mRNA transcriptions of vitellogenin (Vtg) and zona radiata protein (Zrp) genes were analyzed using validated RT-qPCR. Significant increase in Vtg and Zrp transcripts were observed in male tilapias from Awba Dam, compared to males from the reference site. In addition, male tilapias from Awba Dam produced significantly higher Vtg and Zrp mRNA, compared to females in June and July. However, at the natural peak spawning period in August and September, females produced, significantly higher Vtg and Zrp mRNA, compared to males. Fish gonads revealed varying incidence of intersex with a striking presence of two (2) pairs of testes and a pair of ovary in S. melanotheron from Awba Dam. The entire fish population examined at Awba Dam showed a high prevalence of intersex (34.8%), involving phenotypic males and females of both species. Analysis of sediment contaminant levels revealed that As, Cd, Pb, Hg and Ni (heavy metals), monobutyltin cation, 4-iso-nonyphenol and PCB congeners (138, 153 and 180) were significantly higher in Awba Dam, compared to the reference site. Principal component analysis (PCA) showed that fish variables were positively correlated with sediment contaminant burden at Awba Dam, indicating

  5. 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.

  6. PRODUCTIVITY COMPARISON BETWEEN BOER AND KACANG GOAT DAM

    Directory of Open Access Journals (Sweden)

    S. Elieser

    2014-10-01

    Full Text Available A study to evaluate the productivity of Boer and Kacang goats dam was carried out for 2 years atResearch Institute for Goat Production, Sungei Putih-North Sumatera. The materials used were goatsowned by the institute. The parameters observed were total birth and weaning weights of kid, litter size,parity of dam, pre-weaning mortality and kidding interval. The rate of reproduction and productivity ofthe dam were estimated using Amir and Knipscheer methods and were statistically analyzed usingGeneral Linear Model. The results showed that the total birth and weaning weight of Boer goats werehigher (P<0.05 than that of Kacang goats, while litter size of Boer goats were higher (P<0.05 than thatof Kacang goats. The pre-weaning mortality of Boer goat 15.1 ± 6.02% was lower than that ofKacang. The kidding interval of Boer goats was higher (P<0.05 than that of Kacang. Parity of dam hadsignificant effect on all production traits (P<0.05 except for pre-weaning mortality. Dam reproductionrate of Boer (1.81 was higher than that of Kacang (1.78, while productivity of Boer goat (37.12kg/head/year was higher than that of Kacang (18.12. It can be concluded that the reproductivity ofBoer and Kacang goats were similar, however the productivity of Boer goat had better than Kacang.

  7. Dams. Bulletin of the Technical Service of Electric Power and Big Dams; Barrages. Bulletin du Service Technique de l`Energie Electrique et des Grands Barrages

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    Three papers were selected in this issue of the bulletin of the Technical Service of Electric Power and Big Dams. The first one concerns the experience feedback gained from the accident of the Drac river near Grenoble (France) due to a spillover at the Notre-Dame-de-Commiers` dam and which led to the death of 6 children and their teacher. The second one is a report of the conclusions of decennial and annual safety inspections of French dams, while the third one is a report of the Control Services activities for the third quarter of the year 1996 concerning the French dams in operation. (J.S.)

  8. The influence of electrical charge and indolebutyric acid on rooting of willow cuttings

    Directory of Open Access Journals (Sweden)

    R. Domański

    2015-06-01

    Full Text Available Willow cuttings were treated by direct electrical current (DEC, with a negative or a positive electrode inserted inside them, and with the other being outside. Both directions of DEC flow between electrodes stimulated rooting as actively as growth stimulators. The mung bean or oat coleoptile straight growth test showed that the cuttings released some growth promoters into the surrounding water. However, the simultaneous release of some undetected rooting inhibitors was not excluded. The experiment, shows the possibility of changing the chemical regulatory mechanisms of tissues by the use of weak, direct electrical current which causes, the migration of particular substance{s into or from a definite tissue or organ.

  9. Linking Three Gorges Dam and downstream hydrological regimes along the Yangtze River, China

    NARCIS (Netherlands)

    Mei, X.; Dai, Z.; Van Gelder, P.H.A.J.M.; Gao, J.

    2015-01-01

    The magnitude of anthropogenic influence, especially dam regulation, on hydrological system is of scientific and practical value for large river management. As the largest dam in the world by far, Three Gorges Dam (TGD) is expected to be a strong evidence on dam impacts on downstream hydrological

  10. Freshwater mussel survey for the Columbia Dam removal, Paulins Kill, New Jersey

    Science.gov (United States)

    Galbraith, Heather S.; Blakeslee, Carrie J.; Cole, Jeffrey C.; Silldorff, Erik L.

    2018-06-04

    Semi-quantitative mussel surveys, conducted by the U.S. Geological Survey and the Delaware Riverkeeper Network in cooperation with The Nature Conservancy, were completed in the vicinity of the Columbia Dam, on the Paulins Kill, New Jersey, in August 2017 in order to document the mussel species composition and relative abundance prior to removal of the dam. Surveys were conducted from the Brugler Road Bridge downriver approximately 2,000 meters (m) to the Columbia Dam and downriver from the dam about 300 m to 75 m upriver from the confluence of the Paulins Kill with the Delaware River. Sixteen sections (average length=175 m) were surveyed by personnel snorkeling or SCUBA diving; 13 sections were upriver from the dam, and 3 were downriver from the dam. Mussels, as they were encountered by surveyors, were removed from the sediment, immediately identified to species, and replaced in their original collection locations. Habitat data were collected for each surveyed section. Upriver and downriver from the dam, river margins with dense vegetation were examined for mussels by personnel using snorkels in transects (approximately 25 meters) perpendicular to river flow every 50 m on both sides of the river. Only two species were found upriver from the dam, and those were present in relatively low numbers. Catch per unit effort is reported here within parentheses as the average across upriver sections in number of mussels per person hour of survey time: 42 Elliptio complanata (2.6) and 1 Pyganodon cataracta (0.1) were found upriver from the dam. No mussels were found in the dense vegetation either upriver or downriver of the dam by surveyors using snorkels. Significantly higher species richness and mussel catch per unit effort were found downriver from the dam than upriver, including 106 E. complanta (32.5), 27 Utterbackiana implicata (8.2), 1 Alasmidonta undulata (0.4), 2 Lampsilis cariosa (0.5), 6 Lampsilis radiata (2.1), 4 P. cataracta (1.1), and 1 Strophitus undulatus (0

  11. Variability of Ecosystem State in Rivers Containing Natural Dams: A Chemical Analysis

    Science.gov (United States)

    Reynolds, Z. A.

    2015-12-01

    Flooding, and the resulting economic damage to roads and property, is associated with natural dams such as beaver dams or log jams. For this reason, humans often remove natural dams; however, river reaches with natural dams provide very different ecosystem services in comparison with free-flowing river reaches. Therefore, the goal of this project is to assess the differences in ecosystem state between these different river reach types in the northeastern United States. We focused on differences in basic chemistry (e.g., dissolved oxygen, pH, temperature, and organic carbon) to assess the impact of natural dams on river ecosystem state. Study sites include rivers in the White Mountains and southeastern New Hampshire at locations with beaver dams, beaver ponds, beaver meadows, log jams, and free-flowing reaches. Dissolved oxygen, ORP, pH, temperature, and conductivity were measured in the field with a YSI Professional Plus meter. Water samples were collected for subsequent laboratory analysis of total organic carbon with a Shimadzu TOC-L. Preliminary results show that the chemistry of river water varies with feature type. Most significantly, dissolved oxygen concentrations are highest in free-flowing reaches and lowest in beaver ponds. Although beaver ponds are often associated with lower pH, due the increased concentration of organic acids, some beaver ponds can increase pH when compared to free-flowing reaches on the same river. Early results also show that water chemistry returns quickly to the chemistry typical of the free-flowing river reaches after being altered by a natural dam. Overall, natural dams create a river system that has more heterogeneity, and therefore has opportunities to provide more ecosystem functions, than a purely free-flowing river; this can increase the number of supported instream and riparian species. By increasing the understanding of how natural dams affect the chemistry of river water, river engineers can improve their decisions on how

  12. 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...

  13. Geoelectrical Methods and Monitoring for Dam Safety Assessment, Republic of Korea

    Science.gov (United States)

    Lim, S. K.; Oldenburg, D.; Kang, S.; Song, S. H.

    2016-12-01

    Geoelectrical methods and monitoring to detect the seepage and internal erosion are essential for the safety assessment of earth dams. This work aims to develop improved methodologies to analyze the observed data and to monitor changes in seepage flow using direct current (DC) and self-potential (SP) methods. The seasonal variation of water level at dams causes a change in seepage and water saturation and hence alters the resistivity of the dam material. DC data are sensitive to water saturation and hence changes in saturation can be obtained by repeatedly measuring DC data. However, a more diagnostic parameter for safety assessment is fluid flow, and resistivity is only weakly coupled to that. Fortunately SP signals are directly related to fluid flow, and thus an SP survey has the potential to characterize fluid flow through the earth matrix. In Korea, the safety assessment of earth fill dams has been dealt by Korea Rural Community Corporation (KRC). Most of the dams are relatively old ( >50 years), hence assessing deterioration and corresponding seepage of those dams are crucial. In order to evaluate the engineering geological properties of the soil at earth dams in Korea, two boreholes in each dam were drilled to a bedrock depth that exceeds the height of the dam. A large set of field tests, including standard penetration tests (SPT) and in-situ permeability tests, were carried out along the boreholes. However, seepage paths in the dam is complex hence those limited measurements at a few points is not sufficient to delineate the zone of preferential seepage flow. For this, KRC developed permanent DC monitoring systems at a number of agricultural dams in Korea. The data were automatically collected every 6 hours. During the monitoring, the measurements of the water level at two boreholes were gathered at the same time. In this presentation we select an agricultural dam and delineate an anomalous leakage zone by inverting and interpreting time-lapse DC resistivity

  14. Evaluating the Mosul Dam's Instability after Resumption of Maintenance

    Science.gov (United States)

    Al-husseinawi, Y.; Li, Z.; Clarke, P. J.; Edwards, S.

    2017-12-01

    There is serious concern about the safety of Mosul dam in the north of Iraq. Millions of people in the downstream area are exposed to risk of catastrophic collapse of this dam due to its soluble foundation. Recent study (Milillo et al., 2016, Scientific Report/10.1038/srep37408) reported that the dam deformation has accelerated since August 2014, when grouting operations were interrupted due to the conflict in the region. In this study, we investigate the health of Mosul dam since Jun 2016 using three independent datasets: Sentinel-1A/B SAR images, levelling, and GPS measurement. The latter are based on three epochs of terrestrial observation for levelling and GPS data: March 2016, December 2016 and July 2017. During this period, maintenance operations are being recovered to keep the dam stable. The monitoring network, on which the levelling and GPS observations are based, consists of eighty-seven pillars distributed on the dam surface. The results from InSAR and leveling data show that the dam crest is settling by 9 mm/yr. In contrast to previous studies, our results show a deceleration in the settlement. This may be due to the maintenance operations performed in the last few months. InSAR time series analysis was performed using the in-house tool TM-SBAS. When using the small baseline Sentinel-1 constellation, all possibilities of image choice are taken into consideration and the SRTM DEM accuracy is sufficient to generate the differential interferograms. Data from both Sentinel-1A and -1B images are used, and these results can be compared with multi-platform (Envisat, Sentinel-1, Cosmo-SkyMed, and TerraSar-X) data collected during the period between March 2003 and September 2016.

  15. 5. decennial inspection of Tignes dam. Draining of the higher french dam; 5. inspection decennale du barrage de Tignes. Vidange du plus haut barrage de France

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This document deals with the 5. decennial inspection of the Tignes dam. The Tignes dam has been drained to allow EDF and the public authorities to verify the dam wall, of 180 m high, in order to validate the next decade. The four steps of the drainage are described as the maintenance policy of such building. (A.L.B.)

  16. Expansion at Olympic Dam

    International Nuclear Information System (INIS)

    Lewis, C.

    1997-01-01

    The Olympic Dam orebody is the 6th largest copper and the single largest uranium orebody in the world. Mine production commenced in June 1988, at an annual production rate of around 45,000 tonnes of copper and 1,000 tonnes of uranium. Western Mining Corporation announced in 1996 a proposed $1.25 billion expansion of the Olympic Dam operation to raise the annual production capacity of the mine to 200,000 tonnes of copper, approximately 3,700 tonnes of uranium, 75,000 ounces of gold and 950,000 ounces of silver by 2001. Further optimisation work has identified a faster track expansion route, with an increase in the capital cost to $1.487 billion but improved investment outcome, a new target completion date of end 1999, and a new uranium output of 4,600 tonnes per annum from that date

  17. WAC Bennett Dam - the characterization of a crest sinkhole

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, R.A.; Gaffran, P.C. [British Columbia Hydro, Burnaby, BC (Canada); Watts, B.D. [Klohn-Crippen Consultants Ltd., Richmond, BC (Canada); Sobkowicz, J.C. [Thurber Engineering Ltd., Vancouver, BC (Canada); Kupper, A.G. [AGRA Earth and Environmental, Edmonton, AB (Canada)

    1998-11-01

    In June, 1996, a small hole was discovered in the asphaltic concrete road on the crest of the 183 m high WAC Bennett Dam on the Peace River in northeastern British Columbia. Examination of the hole resulted in a sinkhole on the dam crest. The sinkhole was 2.5 m in diameter and 7 m deep. Speculation was that the cavity was likely associated in some way with a buried survey benchmark tube. An investigation was immediately planned and executed to characterize the sinkhole, to determine the extent of damage and the safety status of this very large dam. British Columbia`s Dam Safety Regulator made the decision to lower the reservoir level. During the reservoir drawdown, various surface geophysical techniques were used to investigate the condition of the dam beyond the sinkholes. Intrusive investigations of the sinkhole were also planned. This involved trial drilling and downhole geophysical surveys in intact portions of the core at locations far from the sinkhole. The objectives and criteria developed for the investigation program are summarized. Scope of key activities at the sinkhole and important lessons learned during the investigation are also described. 9 refs., 15 figs.

  18. Phytoremediation of Metal Contaminated Soil Using Willow: Exploiting Plant-Associated Bacteria to Improve Biomass Production and Metal Uptake.

    Science.gov (United States)

    Janssen, Jolien; Weyens, Nele; Croes, Sarah; Beckers, Bram; Meiresonne, Linda; Van Peteghem, Pierre; Carleer, Robert; Vangronsveld, Jaco

    2015-01-01

    Short rotation coppice (SRC) of willow and poplar is proposed for economic valorization and concurrently as remediation strategy for metal contaminated land in northeast-Belgium. However, metal phytoextraction appears insufficient to effectuate rapid reduction of soil metal contents. To increase both biomass production and metal accumulation of SRC, two strategies are proposed: (i) in situ selection of the best performing clones and (ii) bioaugmentation of these clones with beneficial plant-associated bacteria. Based on field data, two experimental willow clones, a Salix viminalis and a Salix alba x alba clone, were selected. Compared to the best performing commercial clones, considerable increases in stem metal extraction were achieved (up to 74% for Cd and 91% for Zn). From the selected clones, plant-associated bacteria were isolated and identified. All strains were subsequently screened for their plant growth-promoting and metal uptake enhancing traits. Five strains were selected for a greenhouse inoculation experiment with the selected clones planted in Cd-Zn-Pb contaminated soil. Extraction potential tended to increase after inoculation of S. viminalis plants with a Rahnella sp. strain due to a significantly increased twig biomass. However, although bacterial strains showing beneficial traits in vitro were used for inoculation, increments in extraction potential were not always observed.

  19. Characteristics of transplacental lead transfer in rat dams and fetuses

    International Nuclear Information System (INIS)

    Kopfler, F.C.; Miller, R.G.; Kowal, N.E.; Kelty, K.C.; Doerger, J.U.; Mills, T.

    1987-01-01

    This study was designed to quantitate the dose resulting from lead exposure during the critical periods of brain development during gestation by determining: (1) if blood lead concentration in rat dams is affected by pregnancy status or duration of lead exposure, (2) if lead concentration in fetuses is associated with the duration of dam exposure, (3) the rates of lead absorption and elimination in pregnant and nonpregnant dams; and (4) the effect that prebreeding exposure on lead kinetics in the dam and upon fetus blood lead concentrations. The results of experiments in which the dams' drinking water contained 50 mg/L lead indicate blood lead levels (after normalizing by water consumption on a body weight basis) of pregnant rats are significantly higher than blood lead levels of non-pregnant rats. Statistical differences in blood lead levels were observed by day 15 of gestation and continue through day 20 of gestation. These blood lead differences are not due to lead treatment prior to breeding as seen when comparing Figure 1 and Figure 2. The blood lead levels of the fetuses at day 20 of gestation were 50-60% higher than that of the corresponding dams. The results from the latter two phases were ambiguous, due to large variability in individual animal absorption and elimination rates. However, the following observations can be made. Preexposure to lead does not affect the percent of lead transferred from the dams' blood to the fetuses. The rate of elimination of lead from the dams' blood does not appear to be affected by prebreeding exposure to lead or by the status of pregnancy. The fraction of the 203 Pb dose transferred to the fetus increases dramatically toward the end of gestation. The data suggest that lead absorption from the gut of pregnant rats is higher than that for nonpregnant rats

  20. Influence of check dams on debris-flow run-out intensity

    Directory of Open Access Journals (Sweden)

    A. Remaître

    2008-12-01

    Full Text Available Debris flows are very dangerous phenomena claiming thousands of lives and millions of Euros each year over the world. Disaster mitigation includes non-structural (hazard mapping, insurance policies, active structural (drainage systems and passive structural (check dams, stilling basins countermeasures. Since over twenty years, many efforts are devoted by the scientific and engineering communities to the design of proper devices able to capture the debris-flow volume and/or break down the energy. If considerable theoretical and numerical work has been performed on the size, the shape and structure of check dams, allowing the definition of general design criteria, it is worth noting that less research has focused on the optimal location of these dams along the debris-flow pathway.

    In this paper, a methodological framework is proposed to evaluate the influence of the number and the location of the check dams on the reduction of the debris-flow intensity (in term of flow thickness, flow velocity and volume. A debris-flow model is used to simulate the run-out of the debris flow. The model uses the Janbu force diagram to resolve the force equilibrium equations; a bingham fluid rheology is introduced and represents the resistance term. The model has been calibrated on two muddy debris-flow events that occurred in 1996 and 2003 at the Faucon watershed (South French Alps.

    Influence of the check dams on the debris-flow intensity is quantified taking into account several check dams configurations (number and location as input geometrical parameters. Results indicate that debris-flow intensity is decreasing with the distance between the source area and the first check dams. The study demonstrates that a small number of check dams located near the source area may decrease substantially the debris-flow intensity on the alluvial fans.

  1. Intergarted geophysical investigations by GPR and ERT on the largest rock fill dam in Europe: Monte Cotugno dam (Southern Italy)

    Science.gov (United States)

    Loperte, A.; Bavusi, M.; Cerverizzo, G.; Lapenna, V.; Soldovieri, F.

    2012-04-01

    This work is concerned with the first results of a survey based on the integration of geophysical techniques for the inspection of the Monte Cotugno dam, the largest rock fill dam in Europe. The Monte Cotugno dam, managed by National Irrigation Development and Agrarian Transformation in Puglia, Basilicata and Irpinia is located on the Sinni river (Basilicata District, South Italy) and represents the nodal point in the whole hydraulic system on the Ionic side of Italy; in fact, the dam allows harnessing of the Sinni river water for agricultural, industrial, drinking and domestic purposes. The dam is of the zoned type and consists of a central core in sandy silt and of gravelly-sandy shoulders; its water tightness is ensured by a bituminous conglomerate facing on the upstream side, welded at the bottom to the foundation sealing system. The latter is about 1,900m long and consist of a massive concrete cut-off wall based on the marly-clay formation, 300m long on the right and 600 m long on the left side. On the valley bottom it is made up of a reinforced concrete cut-off wall that is inserted in the marly-clay formation and is surmounted by an inspection and percolation water collection tunnel. The watertight face consists of a bottom levelling layer 7-8 cm thick in semi open-graded bituminous concrete, a 5 cm separation layer in dense-graded bituminous concrete, a drainage layer in very open-graded concrete varying in thickness from 10 to 16 cm from the top of the dam down, two 4-cm top layers in dense-graded bituminous concrete with stepped joints, a finishing sealing coat containing 1.5 kg/cm2 of asphalt. The shallowest part of this layering is started to show incipient small detachments due to thermal solicitations; these detachments represent a possible way for water infiltration in the dam. In this framework, it was decided to perform the identification, characterization and evaluation of the potential loss of water through small cracks in the bituminous concrete

  2. Investigation of seepage under the Wenxiakou dam using radiotracer

    International Nuclear Information System (INIS)

    Li Zhangsu

    1988-01-01

    This paper describes the result of seepage observation on the dam foundation of Wenxiakou Reservoir using radioactive NaI (I-131) as a tracer. The main feature of the observing technique is to ascertain the seepages between the dam foundation and the clay core wall and around the abutment by measuring vertical flow. The results obtained from the observation have provided some important information for planning the engineering project of anti-seepage and reinforcement of the dam foundation and its right abutment. (author). 2 refs, 4 figs, 1 tab

  3. Skyscraper dams in Yunnan : China's new electricity generator should step in

    Energy Technology Data Exchange (ETDEWEB)

    Ryder, G.

    2006-05-12

    The construction of a series of high-head hydroelectric power dams in China's earthquake-prone Yunnan province has raised concerns in China's scientific and environmental communities. The series of skyscraper-high dams are being built to meet Beijing's power production targets without the benefit of market discipline or effective regulatory oversight. Dam building is central to Beijing's plan for tripling the country's hydropower production by 2020. To meet that target, the State Council granted exclusive development rights to Hydrolancang, the Yunnan Huadian Nu River Hydropower Development Company and the Three Gorges Corporation. The Hydrolancang company is building 2 of the world's tallest and most controversial hydro dams on the Lancang River. When completed in 2012, Xiaowan will be the world's tallest arch dam at 292 metres high. Another dam, the 254 metre high Nuozhadu dam is expected to start generating power in 2017. In addition, there are plans for 13 other high dams along the Nu River, one of only 2 major rivers in China that remains free-flowing. This document expressed that China's new electricity regulator should initiate a full-cost review of state dam-building in the earthquake-prone province. It was argued that as state-owned power companies, the dam builders are not market-driven and are shielded from many of the financial risks and environmental liabilities associated with large dams. The author argued that China's electricity regulator should examine the dam builders' projects costs and profits and review the economic implications of the hydro policy for China's power consumers. It was also suggested that the country's modernization goals for the power industry should be reviewed. The immediate concerns are ecological damage and the frequency with which Yunnan province is hit by earthquakes, rock falls and landslides. Experts caution that the extra weight of the high dams and reservoirs

  4. The Influence of Dams on Malaria Transmission in Sub-Saharan Africa.

    Science.gov (United States)

    Kibret, Solomon; Wilson, G Glenn; Ryder, Darren; Tekie, Habte; Petros, Beyene

    2017-06-01

    The construction of dams in sub-Saharan Africa is pivotal for food security and alleviating poverty in the region. However, the unintended adverse public health implications of extending the spatial distribution of water infrastructure are poorly documented and may minimize the intended benefits of securing water supplies. This paper reviews existing studies on the influence of dams on the spatial distribution of malaria parasites and vectors in sub-Saharan Africa. Common themes emerging from the literature were that dams intensified malaria transmission in semi-arid and highland areas with unstable malaria transmission but had little or no impact in areas with perennial transmission. Differences in the impacts of dams resulted from the types and characteristics of malaria vectors and their breeding habitats in different settings of sub-Saharan Africa. A higher abundance of a less anthropophilic Anopheles arabiensis than a highly efficient vector A. gambiae explains why dams did not increase malaria in stable areas. In unstable areas where transmission is limited by availability of water bodies for vector breeding, dams generally increase malaria by providing breeding habitats for prominent malaria vector species. Integrated vector control measures that include reservoir management, coupled with conventional malaria control strategies, could optimize a reduction of the risk of malaria transmission around dams in the region.

  5. Meta-transcriptomics indicates biotic cross-tolerance in willow trees cultivated on petroleum hydrocarbon contaminated soil.

    Science.gov (United States)

    Gonzalez, Emmanuel; Brereton, Nicholas J B; Marleau, Julie; Guidi Nissim, Werther; Labrecque, Michel; Pitre, Frederic E; Joly, Simon

    2015-10-12

    High concentrations of petroleum hydrocarbon (PHC) pollution can be hazardous to human health and leave soils incapable of supporting agricultural crops. A cheap solution, which can help restore biodiversity and bring land back to productivity, is cultivation of high biomass yielding willow trees. However, the genetic mechanisms which allow these fast-growing trees to tolerate PHCs are as yet unclear. Salix purpurea 'Fish Creek' trees were pot-grown in soil from a former petroleum refinery, either lacking or enriched with C10-C50 PHCs. De novo assembled transcriptomes were compared between tree organs and impartially annotated without a priori constraint to any organism. Over 45% of differentially expressed genes originated from foreign organisms, the majority from the two-spotted spidermite, Tetranychus urticae. Over 99% of T. urticae transcripts were differentially expressed with greater abundance in non-contaminated trees. Plant transcripts involved in the polypropanoid pathway, including phenylalanine ammonia-lyase (PAL), had greater expression in contaminated trees whereas most resistance genes showed higher expression in non-contaminated trees. The impartial approach to annotation of the de novo transcriptomes, allowing for the possibility for multiple species identification, was essential for interpretation of the crop's response treatment. The meta-transcriptomic pattern of expression suggests a cross-tolerance mechanism whereby abiotic stress resistance systems provide improved biotic resistance. These findings highlight a valuable but complex biotic and abiotic stress response to real-world, multidimensional contamination which could, in part, help explain why crops such as willow can produce uniquely high biomass yields on challenging marginal land.

  6. Preliminary Risk Assessment of the Southwestern Willow Flycatcher (Empidonax traillii extimus) at the Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Gallegos, A.F.; Gonzales, G.J.; Bennett, K.D.; Mullen, M.A.; Foxx, T.S.

    1998-10-01

    The southwestern willow flycatcher (Empidonax traillii extimus) is the fourth threatened or endangered species to undergo a preliminary assessment for estimating potential risk from environmental contaminants at the Los Alamos National Laboratory. The assessments are being conducted as part of a three-year project to develop a habitat management plan for threatened and endangered species and species of concern at the Laboratory. For the preliminary assessment, estimated doses were compared against toxicity reference values to generate hazard indices (HIs). This assessment included a measure of cumulative effects from multiple contaminants (radionuclides, metals, and organic chemicals) to 100 simulated nest sites located within flycatcher potential habitat. Sources of contaminant values were 10,000-ft{sup 2} grid cells within an Ecological Exposure Unit (EEU). This EEU was estimated around the potential habitat and was based on the maximum home range for the fly catcher identified in the scientific literature. The tools used included a custom FORTRAN program, ECORSK5, and a geographic information system. Food consumption and soil ingestion contaminant pathways were addressed in the assessment. Using a four-category risk evaluation, HI results indicate no appreciable impact is expected to the southwestern willow flycatcher. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, flycatcher habitat, facility siting, and/or facility operations in order to maintain low levels of risk from contaminants.

  7. Structural and productive-developmental characteristics of white willow plantations of different density on humogley in Donji Srem

    Directory of Open Access Journals (Sweden)

    Andrašev Siniša

    2012-01-01

    Full Text Available The study was conducted in two plantations of white willow (Salix alba L. in Donji Srem on the humogley soil type (hydromorphic black soil, which belongs to a narrow-leaved ash forest with remote sedge (Carici remotae - Fraxinetum angustifoliae Jov. et Tom., 1979. The plantations are located in the same depression. The SP (sample plot-1 plantation is 21 years old with a 6×6 m planting spacing, and the SP-2 plantation is 27 years old with a 3×3m planting spacing. Elements of stem growth in the SP-1 plantation showed that with the white willow planting spacing of 6×6 m and a planned 25-year production cycle it is possible to obtain about 250 m3•ha-1 of timber volume, with an 80% net share of technical wood and a 20 % share of pulp wood. The plantation in SP-2 is at the age, which is well above the optimum age in terms of rational management, and the total volume at the age of 27 years is about 300 m3•ha-1, with a 53.7% net share of technical wood and a 46.3% share of pulpwood. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu: praćenje uticaja, adaptacija i ublažavanje

  8. Preliminary Risk Assessment of the Southwestern Willow Flycatcher (Empidonax traillii extimus) at the Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Gallegos, A.F.; Gonzales, G.J.; Bennett, K.D.; Mullen, M.A.; Foxx, T.S.

    1998-01-01

    The southwestern willow flycatcher (Empidonax traillii extimus) is the fourth threatened or endangered species to undergo a preliminary assessment for estimating potential risk from environmental contaminants at the Los Alamos National Laboratory. The assessments are being conducted as part of a three-year project to develop a habitat management plan for threatened and endangered species and species of concern at the Laboratory. For the preliminary assessment, estimated doses were compared against toxicity reference values to generate hazard indices (HIs). This assessment included a measure of cumulative effects from multiple contaminants (radionuclides, metals, and organic chemicals) to 100 simulated nest sites located within flycatcher potential habitat. Sources of contaminant values were 10,000-ft 2 grid cells within an Ecological Exposure Unit (EEU). This EEU was estimated around the potential habitat and was based on the maximum home range for the fly catcher identified in the scientific literature. The tools used included a custom FORTRAN program, ECORSK5, and a geographic information system. Food consumption and soil ingestion contaminant pathways were addressed in the assessment. Using a four-category risk evaluation, HI results indicate no appreciable impact is expected to the southwestern willow flycatcher. Information on risk by specific geographical location was generated, which can be used to manage contaminated areas, flycatcher habitat, facility siting, and/or facility operations in order to maintain low levels of risk from contaminants

  9. Surveillance of medium-size dams; Surveillance des barrages de taille moyenne

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    French hydro-power buildings belong to the government and are retroceded by the licence holder when the granting delay comes to an end. Experience has shown that less care is given by licence holders to the maintenance of medium-size dams that to big dams. For this reason, the French Ministry of Industry decided to harmonize and standardize the surveillance practices of medium-size dams. A circular was signed on May 23, 1997 which concerns the 10 to 20 m height dams with water reservoir volumes lower than the H{sup 2} x V{sup 0.5} criterion which is an evaluation of the potential risk of the dam. The surveillance modalities concern: the construction, the licence holder file, the first filling up, the operation, and the periodical safety inspections. (J.S.)

  10. Climate change and the causes of dam failures in Australia

    International Nuclear Information System (INIS)

    Lewis, B.

    2007-01-01

    As a result of poor dam construction methods in Australia and significant droughts occurring over the past 60 years, there is a danger that mistakes made during previous droughts will be repeated. Dams were often built in soils of very low moisture content to ensure a properly compacted bank. As a result of these poor construction methods, the drought years have produced an unusually high number of dam failures. This paper discussed the causes of dam failures such as dispersive clays and defects in associated structures. The discussion on dispersive clays included cracking, piping, tunneling, and slides. Dispersive clays occur in soils whose clay minerals separate into single grains when placed in contact with water and are associated with high soil erodability and their distribution often coincides with the occurrence of erosion gullying, rilling and piping. Dispersive clays in a dam embankment can result in the leaching out of material from the embankment with consequent erosion and failure. Defects in associated structures that were discussed included spillway blockage and outlet pipe blockage. It was concluded that dam failures are seldom due to one particular cause but rather due to one weakness triggering another. It was concluded that failures are difficult and expensive to remedy. 9 refs., 4 figs

  11. Rock Mass Behavior Under Hydropower Embankment Dams: A Two-Dimensional Numerical Study

    Science.gov (United States)

    Bondarchuk, A.; Ask, M. V. S.; Dahlström, L.-O.; Nordlund, E.

    2012-09-01

    Sweden has more than 190 large hydropower dams, of which about 50 are pure embankment dams and over 100 are concrete/embankment dams. This paper presents results from conceptual analyses of the response of typical Swedish rock mass to the construction of a hydropower embankment dam and its first stages of operation. The aim is to identify locations and magnitudes of displacements that are occurring in the rock foundation and grout curtain after construction of the dam, the first filling of its water reservoir, and after one seasonal variation of the water table. Coupled hydro-mechanical analysis was conducted using the two-dimensional distinct element program UDEC. Series of the simulations have been performed and the results show that the first filling of the reservoir and variation of water table induce largest magnitudes of displacement, with the greatest values obtained from the two models with high differential horizontal stresses and smallest spacing of sub-vertical fractures. These results may help identifying the condition of the dam foundation and contribute to the development of proper maintenance measures, which guarantee the safety and functionality of the dam. Additionally, newly developed dams may use these results for the estimation of the possible response of the rock foundation to the construction.

  12. National Dam Inspection Program. Bentleyville Dam (NDI ID Number PA- 1096, DER ID Number 63-49), Ohio River Basin, Tributary North Branch Pigeon Creek, Washington County, Pennsylvania. Phase I Inspection Report

    Science.gov (United States)

    1981-06-01

    controlled manner.V The Bentleyville Dam is a significant hazard-small size dam. TK2 recommended spillway design flood (SDF) for a dam of this size and...the dam was completed in 1938. 9. Evaluation. No major deficiencies were observed during the inspection which were considered as having an immediate

  13. Will river erosion below the Three Gorges Dam stop in the middle Yangtze?

    Science.gov (United States)

    Lai, X.; Yin, D.; Finlayson, B. L.; Wei, T.; Li, M.; Yuan, W.; Yang, S.; Dai, Z.; Gao, S.; Chen, Z.

    2017-11-01

    The environmental impact of the Three Gorges Dam has been a subject of vigorous academic, political and social debate since its inception. This includes the key issue of post-dam river channel erosion, which was predicted by the feasibility study to extend to the river mouth. In this paper we examine the geomorphic response of the channel of the middle Yangtze for 660 km downstream of the dam. Using data on channel characteristics, bed material and sediment transport, we show that in the decade following the dam closure, pre-dam seasonal erosion has been replaced by year-round erosion, a pattern most marked at the upstream end of the study area. The sediment carrying capacity of the river channel has been largely reduced below the da