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Ivins, Daniel. "Welsh dams and reservoirs." Dams and Reservoirs 28, no. 3 (September 2018): 89–90. http://dx.doi.org/10.1680/jdare.2018.28.3.89.
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Chander, Ramesh. "Can dams and reservoirs cause earthquakes?" Resonance 4, no. 11 (November 1999): 4–13. http://dx.doi.org/10.1007/bf02837323.
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Agostinho, AA, FM Pelicice, and LC Gomes. "Dams and the fish fauna of the Neotropical region: impacts and management related to diversity and fisheries." Brazilian Journal of Biology 68, no. 4 suppl (November 2008): 1119–32. http://dx.doi.org/10.1590/s1519-69842008000500019.
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Reservoirs have been built in almost all of the hydrographic basins of Brazil. Their purposes include water supply for cities, irrigation and mainly, generation of electricity. There are more than 700 large dams and associated reservoirs in the large rivers of the country. These reservoirs favor local and regional economic development, but they also bring serious and irreversible alterations in the natural hydrologic regime of rivers, affecting habitat quality and the dynamics of the biota. In the impounded area, the main impact is the change from lotic to lentic water, which influences aquatic fauna, including fishes. Impacts of reservoirs present relevant spatiotemporal variations. Immediately after reservoir formation, fish species richness usually increases due to incorporation of surrounding habitats, but richness decreases as reservoirs age. However, impacts downstream of dams appear to be similar or stronger than those that occur within the reservoir. Dams promote discharge control, altering the seasonal cycles of floods. These effects are augmented when dams are constructed in cascades. Therefore, dams profoundly influence composition and structure of fish assemblages. Most affected species are the rheophilics and long distance migratory that require distinct habitats to fulfill their life cycles. Populations of migratory species may collapse or even disappear in intensely regulated stretches. Management actions taken to minimize impacts of dams in Brazil historically considered construction of fish passages, fishery control and stocking. The results of these actions are questionable and/or with clear failures. In this paper, we give emphasis to the Paraná River basin, the most affected by dams in Brazil. We describe some patterns in the alteration and decline in fish diversity in areas influenced by dams. We also discuss negative consequences in the fishery and ecosystems functioning. Finally, we argue the relevance and the success of the management actions taken and present some suggestions to improve conservation of the ichthyofauna in South American basins influenced by dams.
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Freysteinsson, S., and S. Helgason. "Groundwater Modelling for Hydropower Development in Iceland." Hydrology Research 17, no. 4-5 (August 1, 1986): 407–16. http://dx.doi.org/10.2166/nh.1986.0032.
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Groundwater problems in moberg and lava formations are frequently encountered in connection with development of hydroelectric power resources in the volcanic zones in Iceland. The paper gives account of experience by VST from design work and evaluation of performance related to groundwater and seepage at some of Landsvirkjun's projects in Southwest Iceland. The major problems encountered are: leakage under dams on lava, seepage from reservoirs on lava and moberg formations, seepage from canals and dewatering of excavations. The most relevant problems are associated with dams founded on lava and seepage from reservoirs on lava. The discussion is concentrated on three such dams, at Thorisos, Hrauneyjafoss and Sultartangi. Brief description is given of the methods used for estimating seepage and comparisons between forecasts and observations after construction. In general the reservoirs and structures have performed satisfactorily.
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Hughes, Andy. "News: Dams and reservoirs conduits – a new guide." Dams and Reservoirs 22, no. 3-4 (September 2012): 97–98. http://dx.doi.org/10.1680/dare.13.00010.
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McMahon, T. A., and C. Petheram. "Australian dams and reservoirs within a global setting." Australasian Journal of Water Resources 24, no. 1 (January 2, 2020): 12–35. http://dx.doi.org/10.1080/13241583.2020.1733743.
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MUHAMMAD, S. A., A. ADNAN, A. AMIR, I. A. ALI, and D. T. SALISU. "EFFECTS OF HUMAN ACTIVITIES ON THE UTILIZATION OF SOME DAMS IN KANO STATE." Journal of Agricultural Science and Environment 18, no. 1 (November 7, 2019): 151–58. http://dx.doi.org/10.51406/jagse.v18i1.1921.
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Rapid population growth coupled with climate variability especially inconsistent rainfall necessitates the construction of dams/reservoirs to augment the inadequacy of rainfall for food production, water supply and sustainable development. This study identified and assessed the effects of human activities on the function and utilization of some dams in Kano State, through field observations, interview and analysis of relevant data. The results indicated that various human activities such sand excavation along the spillway, clearing of vegetation for irrigation and farming within the perimeters of the dams have led to serious gulley erosion and consequently large quantities of sediment transported and deposited (siltation) in the bed of the dams, while the use of agrochemical for irrigation led to rapid emergence and growth of aquatic grasses due to eutrophication, thus leading to increase in turbidity and channel blockage which impedes smooth water supply in the downstream areas. The result also shows that the reservoirs installation capacities are declining with age at different alarming rates due to sedimentation. Marashi dam remarkably declined by 18%, Pada and Magaga dams each reduced by 15.5% and Guzu-Guzu dam suffered 15.4% reduction. Watari dam is reduced by 14% while Gari, Tomas, Karaye and Challawa-Gorge dams declined by 6.4%, 7.5%, 8.5% and 9.08% respectively. This rate of capacity reduction of the reservoirs due to sedimentation spanned within 45years of existence (1971-2016) which makes the state losing a whopping 5.75M 3 Mil of water annually. The study thus; proffer some precautionary measures on the optimal functioning and utilization of the dams.
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Sadaoui, Mahrez, Wolfgang Ludwig, François Bourrin, Yves Bissonnais, and Estela Romero. "Anthropogenic Reservoirs of Various Sizes Trap Most of the Sediment in the Mediterranean Maghreb Basin." Water 10, no. 7 (July 12, 2018): 927. http://dx.doi.org/10.3390/w10070927.
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The purpose of this study is to obtain a spatially explicit assessment of the impact of reservoirs on natural river sediment fluxes to the sea in the Mediterranean Maghreb Basin (MMB), a region where both mechanical erosion rates and the anthropogenic pressure on surface water resources are high. We combined modeling of riverine sediment yields (sediment fluxes divided by the drainage basin area) and water drainage intensities in a 5’ × 5’ grid point resolution (~10 km × 10 km) with a compilation of existing reservoirs in the area, and calculated sediment trapping based on average water residence time in these reservoirs. A total number of 670 reservoirs could be assembled from various sources (including digitization from Google maps), comprising large-scale, small-scale and hillside reservoirs. 450 of them could be implemented in our modeling approach. Our results confirm that natural sediment yields are clearly above the world average, with the greatest values for Morocco (506 t km−2 year−1), followed by Algeria (328 t km−2 year−1) and by Tunisia (250 t km−2 year−1). Including dams in the downstream routing of suspended sediments to the sea reduces the natural sediment flux in the entire MMB to the sea from 96 to 36 Mt km−1 year−1, which corresponds to an average sediment retention of 62%. Trapping rates are highest in the Tunisian basin part, with about 72%, followed by the Algerian (63%) and the Moroccan basin parts (55%). Small reservoirs and hillside reservoirs are quantitatively important in the interception of these sediments compared to large reservoirs. If we only considered the dams included in the widely used Global Reservoir and Dam (GRanD) database which comprises mainly large reservoirs sediment retention behind dams would account for 36% of the natural suspended particulate matter (SPM) flux to the Mediterranean Sea. Our data reveal negative correlation between sediment retention and natural erosion rates among the three Maghreb countries, which can be explained by the greater difficulties to build dams in steep terrains where natural sediment yields are high. Although the lowest sediment retention rates are found in the Moroccan part of the MMB, it is probably here where riverine sediment starvation has the greatest impacts on coastline dynamics. Understanding the impact of dams and related water infrastructures on riverine sediment dynamics is key in arid zones such as the MMB, where global warming is predicted to cause important changes in the climatic conditions and the water availability.
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Vaikasas, Saulius, Nijole Bastiene, and Virginija Pliuraite. "IMPACT OF SMALL HYDROPOWER PLANTS ON PHYSICOCHEMICAL AND BIOTIC ENVIRONMENTS IN FLATLAND RIVERBEDS OF LITHUANIA." Journal of Water Security 1, no. 1 (February 27, 2015): 1–13. http://dx.doi.org/10.15544/jws.2015.001.
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The impact of a small hydropower plant (SHP) on river water quality and macroinvertebrates has been investigated in 5 Lithuanian rivers and involved 17 dams of which ten are in a sequence in the same river system. The hydrostatic head of SHP dams ranged from 2.75 to 14.50 m and the capacities of their reservoirs varied from 40×103 to 15,500×103 m3. Physicochemical characteristics, as well as macroinvertebrate communities, were evaluated in sites above and below the SHP dams comparing them with reference sites. It was established that construction of SHP dams (H15 m) in Lithuania substantially changed regimes of suspended solids, fine particles and nutrients only locally regardless of hydrostatic head of the dam. Compared to reference sites, SHP reservoirs and sites below SHP dams had relatively more Chironomidae larvae and Oligochaeta, and less Coleoptera larvae as well as the relative abundance of pollution-sensitive Ephemeroptera and EPT. Water quality according to biotic indexes (DSFI and HBI) in the sites influenced by SHP dams was recognised to be moderate or poor, but impact was only local. This suggests that increment of catchment’s area and intensive land use for agriculture within the river basin plays more important role than SHP dams
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Prianto, Eko, Chairulwan Umar, Endi Setiadi Kartamihardja, and Husnah Husnah. "PENGELOLAAN DAN PEMANFAATAN PERAIRAN EMBUNG DAN BENDUNG DI PROVINSI NUSA TENGGARA TIMUR." Jurnal Kebijakan Perikanan Indonesia 9, no. 2 (January 22, 2018): 105. http://dx.doi.org/10.15578/jkpi.9.2.2017.105-114.
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Provinsi Nusa Tenggara Timur (NTT) memiliki sekitar 680 buah embung dan bendung berukuran antara 0,5-155 ha, dengan luas total 1.630 ha. Potensi sumber daya perairan tersebut belum dimanfaatkan untuk pengembangan perikanan. Dewasa ini, badan air tersebut hanya berfungsi sebagai penampung air untuk keperluan irigasi pertanian dan minum ternak serta kebutuhan air rumah tangga. Tulisan ini bertujuan untuk merumuskan upaya pengelolaan dan pemanfaatan embung serta bendung yang berbasis budidaya (culture-based fisheries/CBF) di Provinsi Nusa Tenggara Timur. Metodologi pengumpulan data dan informasi dilakukan dengan studi literatur yang dianalisis secara deskriptif. Potensi produksi ikan di embung dan bendung di NTT diperkirakan berkisar antara 34.3-55.8kg/ha/th dengan kondisi kualitas air yang masih baik dan mampu mendukung kehidupan organisme terutama ikan. Beberapa perairan embung dan bendung memiliki tingkat kesuburan sedang (mesotrof) hingga sangat tinggi (hypereutrof) dengan jenis plankton yang mendominasi yaitu kelas Cyanophyceae (genera Anabaena dan Oscilatoria) dan Dynophyceaea (Peridinium). Kelembagaan pengelola sumber daya ikan belum terbentuk, namun kelompok tani yang terlibat dalam pengelolaan badan air dengan struktur organisasi yang jelas sudah ada. Agar kegiatan CBF dapat berjalan dengan baik maka pemerintah daerah harus mengoptimalkan produksi benih di hatchery ikan bandeng dan menyusun regulasi yang mengatur penebaran ikan dan penerapan CBF.In East Nusa Tenggara Province there are 680 small reservoirs and dams (range from 0.5 to 155 ha/unit), with the total waters area of around 1,630 ha. Its high potential resources have not been utilized yet for fisheries. Nowadays, NTT’s dams and reservoirs are only be utilized for agricultural irrigation, livestock and household needs. Culture-based fisheries (CBF) is a technology that is suitable and recommended to be applied and developed in reservoirs or dams, because it does not alter the function ofthe reservoir. This paper aims to formulate cultured based fisheries management and utilization efforts of dams and small reservoirs in East Nusa Tenggara. Desk study was used to collect data and information, and analized and descriptively.The results show that the fish production potential of dams and reservoirs in NTT province was around 34.3-55.8 kg/ha/year. Most of the dams and reservoirs have clear water and able to support aquatic organism particulalrly for fish as the main exploited resources.Productivity levels varied from mesotrof to hypereutrof, inhabited by plankton group dominated by Cyanophyceae (Anabaena dan Oscilatoria) and Dynophyceae (Peridinium). The formal agency responsible to manage the resources was not established yet; however, some groups of fishers who directly utilized the resources have been developed. The local government of NTT should optimally increased the productivity of their owned hatchery to produce milk fish fry and able to arrange the regulation which guides the restocking and CBF implementation.
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Chen, Qiuwen, Wenqing Shi, Jef Huisman, Stephen C. Maberly, Jianyun Zhang, Juhua Yu, Yuchen Chen, Daniele Tonina, and Qitao Yi. "Hydropower reservoirs on the upper Mekong River modify nutrient bioavailability downstream." National Science Review 7, no. 9 (February 17, 2020): 1449–57. http://dx.doi.org/10.1093/nsr/nwaa026.
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Abstract Hydropower development is the key strategy in many developing countries for energy supply, climate-change mitigation and economic development. However, it is commonly assumed that river dams retain nutrients and therefore reduce downstream primary productivity and fishery catches, compromising food security and causing trans-boundary disputes. Contrary to expectation, here we found that a cascade of reservoirs along the upper Mekong River increased downstream bioavailability of nitrogen and phosphorus. The dams caused phytoplankton density to increase with hydraulic residence time and stratification of the stagnant reservoirs caused hypoxia at depth. This allowed the release of bioavailable phosphorus from the sediment and an increase in dissolved inorganic nitrogen as well as a shift in nitrogen species from nitrate to ammonium, which were transported downstream by the discharge of water from the base of the dam. Our findings provide a new perspective on the environmental impacts of river dams on nutrient cycling and ecosystem functioning, with potential implications for sustainable development of hydropower worldwide.
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Yang, De Wei, Jin Bao Sheng, Xue Hui Peng, and Ying Ying Chen. "Dams Risk Sequence Based on the Dam Defects." Applied Mechanics and Materials 170-173 (May 2012): 2051–55. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.2051.
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Priority invested to conduct danger control and reinforcement according to the severity and risks of dams is a vital issue to Chinese government and administrative departments faced because of the large amounts of dangerous reservoirs. Dams risk sequence based on the dam deficiencies offers a new idea of danger control and reinforcement and its sequence decision-making.
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Šádková, Eva, and Bohumír Janský. "Splash dams in the Krkonoše Mts: from the history to their possible use." Geografie 125, no. 3 (2020): 291–317. http://dx.doi.org/10.37040/geografie2020125030291.
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This paper summarizes findings from historical sources and literature dealing with the small water reservoirs (splash dams) in the Krkonoše (Giant) Mts. Based on old maps and historical records in archives and regional museums, this study describes the original causes and period of origin of the splash dams, and deals with their function and their location in the field. Additionally, this paper focuses on the mechanism of log driving in this area to fully understand the entire organized procedure. Up to twenty-four splash dams, built in the Krkonoše Mts mainly in the second half of the sixteenth century, were traced in historical records. At the end, there were given examples of some localities in relation to the possible idea of the restoration of some former small water reservoirs with an effort to gradually increase water retention capacity, and reduce runoff variability in headstream areas.
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Froehlich, David C. "Estimating Reservoir Sedimentation at Large Dams in India." E3S Web of Conferences 40 (2018): 03042. http://dx.doi.org/10.1051/e3sconf/20184003042.
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Mathematical expressions are developed that relate the storage capacity loss of reservoirs in India to the catchment area, the reservoir surface area, the original storage volume, and the time since the first filling of the impoundment. The relations for sedimentation of reservoirs found on eastward and westward flowing rivers differ significantly, because of meteorological and geological influences on land surface runoff and sediment yield within reservoir catchments. The formulations give good fits to the assembled data and allow an uncomplicated calculation of the half-life of reservoirs (that is, the time needed for the storage capacity to be reduced by 50%), which offers a measure of when sedimentation will have a significant adverse impact on the functioning of dams.
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Chow, Ming Fai, Muhammad Aliff bin Bakhrojin, Harizah Haris, and Akhilash Aravind A/L Dinesh. "Assessment of Greenhouse Gas (GHG) Emission from Hydropower Reservoirs in Malaysia." Proceedings 2, no. 22 (November 6, 2018): 1380. http://dx.doi.org/10.3390/proceedings2221380.
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This paper presents a preliminary assessment of greenhouse gas (GHG) emissions from all major hydropower reservoirs in Malaysia from the period of 1930–2017. The GHG emissions are calculated based on the Tier 1 method as recommended in International Government Panel on Climate Change (IPCC) guidelines. The results showed that approximately 151.64 Gg of annual methane emission released from hydropower dams in Peninsular Malaysia. While in East Malaysia, hydropower dams release 235.7 Gg of methane emission annually. Bakun dam contributes the most 41.26% of total annual methane emission from hydropower dams in Malaysia. Ulu Jelai hydroelectric dam with design power capacity of 372 MW contributes the least CH4 emission of 0.02 Gg CH4 yr−1. It is seen that high head hydroelectric dam with small reservoir surface area is the most sustainable hydropower dam in reducing the GHG emission. However, long-term measurements must be made in order to clarify the net GHG emissions from reservoir surface, turbines, spillway and downstream river of hydropower dams in Malaysia.
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Palchenko, O. "DAMS AND WATER RESERVOIRS AS A FACTOR OF ENVIRONMENTAL IMPACT." Scientific Bulletin of Civil Engineering 95, no. 1 (2019): 141–46. http://dx.doi.org/10.29295/2311-7257-2019-95-1-141-146.
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Goodland, >R. "The world bank's new environmental policy for dams and reservoirs." International Journal of Water Resources Development 6, no. 4 (December 1990): 226–39. http://dx.doi.org/10.1080/07900629008722478.
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Qureshi, Saqib, Raymond Fontaine, Samuel Saleeb, and Joel Stein. "A Simulation-Based Approach for Evaluating Cost and Performance of a Sediment Removal and Processing System for the Lower Susquehanna River Dams." Industrial and Systems Engineering Review 3, no. 2 (July 16, 2015): 107–16. http://dx.doi.org/10.37266/iser.2015v3i2.pp107-116.
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A series of three major dams and reservoirs located along the Lower Susquehanna River have historically acted as a system of sediment and nutrient pollution traps. However, episodic pulses of these pollution loads are released following short-term extreme storm events, affecting subaquatic vegetation, benthic organisms, and the overall water quality in the Upper Chesapeake Bay. In addition, all three reservoirs have reached a state of near maximum storage capacity termed as dynamic equilibrium. Based on prior research, this study seeks to reduce the sediment buildup behind the dams through a sediment removal and processing operation, and thereby reduce the ecological impact of major storms. A set of scour performance curves derived from a regression analysis, and a stochastic lifecycle cost model were used to evaluate the sediment scouring reduction and economic feasibility of three processing alternatives: Plasma Vitrification, Cement-Lock, and Quarry/Landfill, and three removal amount cases: Nominal, Moderate, and Maximum. Since the scour performance curves treat the dams as static, a fluid system dynamics model was used to determine if the dynamic interaction between the capacitance of the dams during major scouring events is negligible or considerable. A utility vs. cost analysis factoring in time, performance, and suitability of the alternatives indicates that a Cement-Lock processing plant at moderate dredging for the Safe Harbor and Conowingo Dams is the most cost-performance effective solution.
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Evans, Stephen G. "The maximum discharge of outburst floods caused by the breaching of man-made and natural dams." Canadian Geotechnical Journal 23, no. 3 (August 1, 1986): 385–87. http://dx.doi.org/10.1139/t86-053.
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The sudden release of water impounded in natural and man-made reservoirs has been responsible for some major disasters in mountainous regions of the world. Recent natural damming events and failures of natural dams have illustrated the need to examine the nature and magnitude of outburst floods and the behaviour of debris dams in general. An empirical relationship between maximum discharge (Qmax) and volume of water released during the outburst event (Vmax) is established (Qmax = 0.72Vmax0.53) for man-made dams and the relationship is thought applicable to the breaching of natural debris dams (landslides and moraines). This relationship allows a first-order estimate to be made of Qmax in the vicinity of the breach for a given Vmax during the failure of a man-made dam or a natural debris dam. Key words: outburst floods, man-made dams, natural dams, landslide, dam failure.
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Suzuki, Fábio Mineo, Lucas Vilela Pires, and Paulo Santos Pompeu. "Passage of fish larvae and eggs through the Funil, Itutinga and Camargos Reservoirs on the upper Rio Grande (Minas Gerais, Brazil)." Neotropical Ichthyology 9, no. 3 (2011): 617–22. http://dx.doi.org/10.1590/s1679-62252011000300014.
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The objective of this study was to evaluate the passage of fish eggs and larvae through the Funil, Itutinga and Camargos Reservoirs, located in the upper Rio Grande basin, Minas Gerais, Brazil. Samples were taken downstream and upstream of the dams using a conical ichthyoplankton net and were collected every two weeks, twice per sampling day, between November 2008 and March 2009. Although eggs and larvae were abundant immediately upstream of the reservoirs, no ichthyoplankton were captured immediately downstream of the dams, possibly indicating that eggs and larvae do not pass through the reservoirs. The arrival of ichthyoplankton in the reservoirs without its effective passage downstream makes the survival of these eggs and larvae unlikely. Furthermore, this lack of downstream movement may compromise the recruitment of species to downstream stretches, especially in the case of the Funil Reservoir (because of the presence of a fish pass in this dam). We emphasize that the fish lift operation at the Funil Dam must be carefully assessed, considering not only its efficiency but also its short- and long-term effects on the recruitment of migratory fish species from the river.
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Winton, Robert Scott, Elisa Calamita, and Bernhard Wehrli. "Reviews and syntheses: Dams, water quality and tropical reservoir stratification." Biogeosciences 16, no. 8 (April 23, 2019): 1657–71. http://dx.doi.org/10.5194/bg-16-1657-2019.
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Abstract. The impact of large dams is a popular topic in environmental science, but the importance of altered water quality as a driver of ecological impacts is often missing from such discussions. This is partly because information on the relationship between dams and water quality is relatively sparse and fragmentary, especially for low-latitude developing countries where dam building is now concentrated. In this paper, we review and synthesize information on the effects of damming on water quality with a special focus on low latitudes. We find that two ultimate physical processes drive most water quality changes: the trapping of sediments and nutrients, and thermal stratification in reservoirs. Since stratification emerges as an important driver and there is ambiguity in the literature regarding the stratification behavior of water bodies in the tropics, we synthesize data and literature on the 54 largest low-latitude reservoirs to assess their mixing behavior using three classification schemes. Direct observations from literature as well as classifications based on climate and/or morphometry suggest that most, if not all, low-latitude reservoirs will stratify on at least a seasonal basis. This finding suggests that low-latitude dams have the potential to discharge cooler, anoxic deep water, which can degrade downstream ecosystems by altering thermal regimes or causing hypoxic stress. Many of these reservoirs are also capable of efficient trapping of sediments and bed load, transforming or destroying downstream ecosystems, such as floodplains and deltas. Water quality impacts imposed by stratification and sediment trapping can be mitigated through a variety of approaches, but implementation often meets physical or financial constraints. The impending construction of thousands of planned low-latitude dams will alter water quality throughout tropical and subtropical rivers. These changes and associated environmental impacts need to be better understood by better baseline data and more sophisticated predictors of reservoir stratification behavior. Improved environmental impact assessments and dam designs have the potential to mitigate both existing and future potential impacts.
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Verdugo, Ramon, Nicholas Sitar, J. David Frost, Jonathan D. Bray, Gabriel Candia, Terry Eldridge, Youssef Hashash, Scott M. Olson, and Alfredo Urzua. "Seismic Performance of Earth Structures during the February 2010 Maule, Chile, Earthquake: Dams, Levees, Tailings Dams, and Retaining Walls." Earthquake Spectra 28, no. 1_suppl1 (June 2012): 75–96. http://dx.doi.org/10.1193/1.4000043.
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The 27 February 2010 Maule, Chile, earthquake occurred during the driest time of the year, which implied that most of the soils in the slopes were not saturated and that the dams had extra freeboard. This may explain the small number of slope failures caused by the earthquake. However, two important earth dams suffered seismically induced permanent ground movements, but no catastrophic damage was reported because the reservoirs levels were low. Five medium-sized mine tailings dams failed due to liquefaction; one of them tragically caused four casualties. Retaining structures of all types performed well and no failures were observed.
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Ulseth, A. J., and R. O. Hall. "Dam tailwaters compound the effects of reservoirs on the longitudinal transport of organic carbon in an arid river." Biogeosciences 12, no. 14 (July 28, 2015): 4345–59. http://dx.doi.org/10.5194/bg-12-4345-2015.
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Abstract. Reservoirs on rivers can disrupt organic carbon (OC) transport and transformation, but less is known how river reaches directly below dams contribute to OC processing. We compared how reservoirs and their associated tailwaters affected OC quantity and quality by calculating particulate OC (POC) and dissolved OC (DOC) fluxes, and measuring composition and bioavailability of DOC. We sampled the Yampa River near Maybell, Colorado, USA, and the Green River above and below Fontenelle and Flaming Gorge reservoirs as well as their respective tailwaters from early snowmelt to base flow hydrological conditions. In unregulated reaches (Yampa River, Green River above Fontenelle reservoir), DOC and POC concentrations increased with snowmelt discharge. POC and DOC concentrations also increased with stream discharge below Fontenelle reservoir, but there was no relationship between DOC and stream flow below Flaming Gorge reservoir. The annual load of POC was 3-fold lower below Fontenelle Reservoir and nearly 7-fold lower below Flaming Gorge reservoir, compared to their respective upstream sampling sites. DOC exported to downstream reaches from both reservoirs was less bioavailable, as measured with bioassays, than DOC upriver of the reservoirs. Lastly, tailwater reaches below the reservoirs generated OC, exporting potentially 1.6–2.2 g C m−2 d−1 of OC to downstream ecosystems. Therefore, the effect of impounding rivers on C fluxes is greater than the impact of the reservoirs alone given the additive effect of tailwater reaches below dams, which may produce and export comparable amounts of likely autochthonous carbon to downstream reaches.
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Tang, Alex, Durgesh C. Rai, David Ames, C. V. R. Murty, Sudhir K. Jain, Suresh R. Dash, Hemant B. Kaushik, et al. "Lifeline Systems in the Andaman and Nicobar Islands (India) after the December 2004 Great Sumatra Earthquake and Indian Ocean Tsunami." Earthquake Spectra 22, no. 3_suppl (June 2006): 581–606. http://dx.doi.org/10.1193/1.2205874.
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Lifeline systems in the Andaman and Nicobar islands performed poorly during the December 2004 Great Sumatra earthquake and tsunami. Several power stations and transmission lines were damaged by the ground shaking, affecting the electric power supply to parts of the islands. Telecommunication services were severely affected because of destruction of several telephone exchanges. These services were restored quickly by government agencies. The dams and reservoirs, which supply potable water, sustained minor damage from ground shaking. However, segmented pipelines connecting the dams and reservoirs to various storage sites broke at several places, which significantly affected the water supply for a few days. Ground shaking damaged several elevated as well as ground-supported storage tanks. Damage related to tsunami waves was substantial in the 500–1,000- m strip immediately next to the coastline.
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Reynalte-Tataje, David A., Alex P. O. Nuñer, Michele C. Nunes, Valquíria Garcia, Carolina A. Lopes, and Evoy Zaniboni-Filho. "Spawning of migratory fish species between two reservoirs of the upper Uruguay River, Brazil." Neotropical Ichthyology 10, no. 4 (October 2012): 829–35. http://dx.doi.org/10.1590/s1679-62252012000400016.
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This study investigated the migratory fish spawning within the reservoirs of the Machadinho and Itá dams (upper Uruguay River, Brazil) and its relationship to environmental variables. Sampling was conducted in the lotic region of the river in two sites between the dams' reservoirs: Uruguay (main river) and Ligeiro (tributary). Sampling included nine consecutive reproductive periods (RP) spanning the period from 2001 to 2010 and was conducted at night on the water surface using cylindrical-conical plankton nets (0.5 mm mesh); environmental variables were also recorded. The spawning of the migratory species Salminus brasiliensis, Prochilodus lineatus, and Steindachneridion scriptum was registered: S. brasiliensis and P. lineatus spawned in the tributary river at the end of spring/beginning of summer, during flooding and during periods of high water temperature. Steindachneridion scriptum spawned in the main river at the beginning of spring. The study showed that S. brasiliensis, P. lineatus, and S. scriptum are able to spawn in small lotic river stretches within two reservoirs, but only under very specific and not common environmental conditions.
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Xue, Jian Rong, Ying Ying Zhang, and Xiang Yang Shi. "Overview of Consolidation Method and Application for the Culvert under the Small or Medium-Sized Earth-Rock Dams." Applied Mechanics and Materials 351-352 (August 2013): 1376–80. http://dx.doi.org/10.4028/www.scientific.net/amm.351-352.1376.
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At present, China's small and medium-sized earth-rock DAMS were built in the early days after liberation, usually the water conveyance structures are culverts under the dams. Owing to the poor operation managements and disrepair, and the restriction and effects of economy and technology, then, the majority of culverts had various problems in seepage. In combination with years of experience in dealing with defective reservoirs, I summarized the common problems of the culvert and reinforcement methods.
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Matsumura, Takayoshi, Hiroshi Kamiya, and Naohiro Yoshida. "Effective Flood Control Through Integrated and Collaborative Dam Operation at Three Dams in the Upper Nabari River." Journal of Disaster Research 7, no. 5 (October 1, 2012): 540–46. http://dx.doi.org/10.20965/jdr.2012.p0540.
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Heavy rain with Typhoon 18 threatened the Nabari River Basin, Kansai region, with inundation early on the morning of October 8, 2009. The Nabari River is a tributary of the Yodo river basin that contains Osaka and Kyoto and runs through Nabari City, which is a residential zone a commutable distance from Osaka city. In the upper reaches of the Nabari, there are three multipurpose dams – Shorenji Dam, Hinachi Dam, and Murou Dam – that are operated by the Kizugawa Integrated Dam Control and Management Office (KIDCMO), a branch office of the Japan Water Agency (JWA). Since it rained heavily downstream from the three dams, regular operation of the dams complying with given flood control regulations appeared unable to save Nabari City from inundation. The JWA and Ministry of Land, Infrastructure, Transport and Tourism (MLIT) therefore conducted collaborative operation of the three dams to avoid inundating the city. In this case, flood control operation of the three dams commenced at an early stage before inflow reached defined flood discharge in consideration of the water level of the Nabari River, rainfall conditions, and the capacity of reservoirs. During operation, discharge from dams was changed in a timely manner and appropriately through collaborative operation of the three dams in order to maximize the effectiveness of all flood control capacities of reservoirs based on the latest rainfall forecast technology and runoff analysis. The use of improved rainfall forecast technology and runoff analysis models enabled effective application of flexible operation protocols. It is estimated that this operation has resulted in a 1.5 m decrease in the water level at the Nabari design control point and saved approximately 1,200 households from inundation. Considering recent climate change, it is possible to have extreme rainfall more often. The proof of the adaptability of this flexible operation is quite meaningful not only for flood damage mitigation in the downstream but also for future prospects of flood control by dams.
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Chen, Pei Pei, and Guo Xin Zhang. "Study on the Prevention Measures and Causes of Cracks in Arch Crests of Galleries in High Concrete Dams." Advanced Materials Research 919-921 (April 2014): 813–19. http://dx.doi.org/10.4028/www.scientific.net/amr.919-921.813.
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More and more high dams with huge reservoirs have been built in China in recent years. A lot of research work on the causes of cracking in galleries of low concrete dams has been carried out at present, while studies on that of high concrete dams are less with the lack of systematic cognition. Based on that, the research on high concrete dams is conducted in this paper, using the method of finite element simulation. It is proven that self-weight action has more influence on the stress of arch crests of galleries existing in high concrete dams, especially the galleries whose overlying concrete height is relatively high. And surface cracks tend to appear in arch crests of these galleries under gravity. In the end, measures for improvement of the stress of arch crest are put forward, of which the effect of enlarging reinforcement is relatively obvious.
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Khamidov, Lutfulla, Alisher Ibragimov, Ilkhom Alimukhamedov, and Khairulla Khamidov. "The processing results of the vibration records from the dams and coastal slopes of the Charvak and Andijan water reservoirs of Uzbekistan during the weak earthquakes." Russian Journal of Seismology 2, no. 4 (December 16, 2020): 28–42. http://dx.doi.org/10.35540/2686-7907.2020.4.03.
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The article discusses the processing results of the vibration records from the dams and coastal slopes of the Charvak and Andijan water reservoirs of Uzbekistan during the weak earthquakes. It is shown, that the seismic monitoring systems were upgraded at the investigated objects. Analyzing seismic estimates, revealed, that the construction of the Charvak reservoir dam has a non-linear behavior, and it is manifested in the differences of the frequency range and transmission coefficient of the dam elements. According to the analysis of seismic data, obtained during the registration of weak earthquakes at the several measuring points of dams and coastal slopes of the Charvak and Andijan reservoirs, the vibration frequencies and the ratio of the vibration velocity amplitudes to the vibration velocity amplitudes of the reference station are varies greatly depending on the azimuth to the epicenter
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Milanović, Petar. "Dams and reservoirs in karst? Keep away or accept the challenges." Hydrogeology Journal 29, no. 1 (January 9, 2021): 89–100. http://dx.doi.org/10.1007/s10040-020-02273-0.
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Yewhalaw, D., S. Hamels, Y. Getachew, P. R. Torgerson, M. Anagnostou, W. Legesse, H. Kloos, L. Duchateau, and N. Speybroeck. "Water resource developments in Ethiopia: potential benefits and negative impacts on the environment, vector-borne diseases, and food security." Environmental Reviews 22, no. 4 (December 2014): 364–71. http://dx.doi.org/10.1139/er-2013-0076.
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To satisfy the growing demand for electricity, Ethiopia plans to increase its electricity production five-fold between 2010 and 2015, mainly through the construction of dams. A literature review shows that while dams can boost power and agricultural production, promote economic development, and facilitate flood control, they can also lead to environmental, ecological, and socioeconomic changes. Several case studies show that dams may alter the composition and density of vectors and intermediate host species, increase the incidence of malaria schistosomiasis and possibly lymphatic filariasis, and lead to eutrophication of reservoirs, soil erosion, and earthquakes. There is evidence that dams and commercial irrigation schemes can increase soil and water degradation, vulnerability to drought, and food insecurity in riverine and lacustrine areas downstream of dams. It appears that dams in Ethiopia are also vulnerable to high soil erosion rates and earthquakes. Consequently, the current and proposed large-scale dam construction program in Ethiopia requires in-depth research to improve our understanding of the unintended negative effects of projects and to guide the location, design, and implementation of appropriate preventive and remedial programs.
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Yoshimura, Takeshi, and Hiroki Shinya. "Environmental Impact Assessment Plan Due to Sediment Sluicing at Dams Along Mimikawa River System." Journal of Disaster Research 13, no. 4 (August 1, 2018): 709–19. http://dx.doi.org/10.20965/jdr.2018.p0709.
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The 2005 typhoon disasters taught us that the Mimikawa River system in Miyazaki Prefecture had various problems with sediments in the river basin (the riverbed in dam reservoirs rise so much that flooding risk increases, sediments captured at dams granulate the downstream river channel and destabilize the bridge piers in the downstream river channel). In one of the approaches to solve these problems simultaneously, since 2017, sediment sluicing at a series of dams has been operated cooperatively. Using this approach, we can expect that the river will recover its continuity of sediment movement, returning its physical environment and animal habitats to their original states. Based on environmental surveys and numerical analyses of the current conditions, we have predicted the environmental impacts due to sediment sluicing at dams and defined the method to assess them. This paper presents: 1) an overview of sediment sluicing at dams in the Mimikawa River system, 2) the analysis of the river environment prior to operating sediment sluicing at dams, 3) the prediction of the impacts of sediment sluicing at dams in the river environment, 4) the environmental impact assessment after operating sediment sluicing at dams.
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Říha, Jaromír, Stanislav Kotaška, and Lubomír Petrula. "Dam Break Modeling in a Cascade of Small Earthen Dams: Case Study of the Čižina River in the Czech Republic." Water 12, no. 8 (August 17, 2020): 2309. http://dx.doi.org/10.3390/w12082309.
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Failures of small dams can pose a serious threat to people and property even if the size of the schemes is relatively low. In many cases, small dams are situated in a cascade along streams, meaning that the failure of the uppermost dam may cause the dams downstream to fail. In this paper, a cascade of three small reservoirs, Lichnov II (14.6 m high), Lichnov III (10 m high), and Pocheň (8.5 m high), is the subject of the dam break analyses carried out via various methods such as empirical formulae, analogy, and hydraulic modeling. The dam-break flood routing was simulated using a shallow water flow hydraulic model. The simulations confirm that the attenuation effect of the peak discharge is governed by the flood volume, slope, and morphology of the floodplain and increases with the distance from the breached dam following an approximately exponential trend. When estimating peak discharge, empirical formulae derived for a single dam break should be applied carefully as they may underestimate the peak outflow by up to 10% in the case of a dam cascade. The attenuation volume of small reservoirs is small when compared to the flood volume, meaning that the attenuation of the peak discharge usually varies between 5–10%.
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Godbout, L., C. C. Wood, R. E. Withler, S. Latham, R. J. Nelson, L. Wetzel, R. Barnett-Johnson, M. J. Grove, A. K. Schmitt, and K. D. McKeegan. "Sockeye salmon (Oncorhynchus nerka) return after an absence of nearly 90 years: a case of reversion to anadromy." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 9 (September 2011): 1590–602. http://dx.doi.org/10.1139/f2011-089.
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We document the recent reappearance of anadromous sockeye salmon ( Oncorhynchus nerka ) that were thought to have been extirpated by the construction of hydroelectric dams on the Coquitlam and Alouette rivers in British Columbia, Canada, in 1914 and 1927, respectively. Unexpected downstream migrations of juveniles during experimental water releases into both rivers in 2005 and 2006 preceded upstream return migrations of adults in 2007 and 2008. Genetic (microsatellite and mitochondrial DNA) markers and stable isotope (δ34S and 87Sr/86Sr) patterns in otoliths confirm that both the juvenile downstream migrants and adult upstream migrants were progeny of nonanadromous sockeye salmon (kokanee) that inhabit Coquitlam and Alouette reservoirs. Low genetic diversity and evidence of genetic bottlenecks suggest that the kokanee populations in both reservoirs originated from relatively few anadromous individuals that residualized after downstream migration was largely prevented by the construction of dams. Once given an opportunity for upstream and downstream migration, both populations appear capable of reverting to a successful anadromous form, even after 25 generations.
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Döll, P., K. Fiedler, and J. Zhang. "Global-scale analysis of river flow alterations due to water withdrawals and reservoirs." Hydrology and Earth System Sciences 13, no. 12 (December 22, 2009): 2413–32. http://dx.doi.org/10.5194/hess-13-2413-2009.
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Abstract. Global-scale information on natural river flows and anthropogenic river flow alterations is required to identify areas where aqueous ecosystems are expected to be strongly degraded. Such information can support the identification of environmental flow guidelines and a sustainable water management that balances the water demands of humans and ecosystems. This study presents the first global assessment of the anthropogenic alteration of river flow regimes, in particular of flow variability, by water withdrawals and dams/reservoirs. Six ecologically relevant flow indicators were quantified using an improved version of the global water model WaterGAP. WaterGAP simulated, with a spatial resolution of 0.5 degree, river discharge as affected by human water withdrawals and dams around the year 2000, as well as naturalized discharge without this type of human interference. Compared to naturalized conditions, long-term average global discharge into oceans and internal sinks has decreased by 2.7% due to water withdrawals, and by 0.8% due to dams. Mainly due to irrigation, long-term average river discharge and statistical low flow Q90 (monthly river discharge that is exceeded in 9 out of 10 months) have decreased by more than 10% on one sixth and one quarter of the global land area (excluding Antarctica and Greenland), respectively. Q90 has increased significantly on only 5% of the land area, downstream of reservoirs. Due to both water withdrawals and reservoirs, seasonal flow amplitude has decreased significantly on one sixth of the land area, while interannual variability has increased on one quarter of the land area mainly due to irrigation. It has decreased on only 8% of the land area, in areas downstream of reservoirs where consumptive water use is low. The impact of reservoirs is likely underestimated by our study as small reservoirs are not taken into account. Areas most affected by anthropogenic river flow alterations are the Western and Central USA, Mexico, the western coast of South America, the Mediterranean rim, Southern Africa, the semi-arid and arid countries of the Near East and Western Asia, Pakistan and India, Northern China and the Australian Murray-Darling Basin, as well as some Arctic rivers. Due to a large number of uncertainties related e.g. to the estimation of water use and reservoir operation rules, the analysis is expected to provide only first estimates of river flow alterations that should be refined in the future.
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Paredes-Beltran, Bolivar, Alvaro Sordo-Ward, B. de-Lama, and Luis Garrote. "A Continental Assessment of Reservoir Storage and Water Availability in South America." Water 13, no. 14 (July 20, 2021): 1992. http://dx.doi.org/10.3390/w13141992.
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This study presents the first continental assessment of water storage and its influence on the availability of water of the river systems of South America. Although hydraulic infrastructure has the potential to cause several impacts on river systems and the environment, their relevance in water resources systems is irrefutable. The human services that dams and reservoirs provide to society, e.g., hydroelectricity, water supply, irrigation, or flood control, are vital services that society requires to develop. Despite this fact, the interactions of dams and reservoirs in the river systems of South America have not been explored from a hydrological perspective. In this study, we present the first assessment of the potential effects of water storage at a basin scale in South America. For this purpose, first we present an analysis of the current conditions and the influence of water storage in the basins of the continent. Then, we estimate the potential water availability of each basin, to evaluate the role of water storage in the availability of water in the continent. Our findings indicate that the ‘Colorado’ and ‘Negro’ basins in Argentina are the most influenced by water storage in the continent. Moreover, our results suggest that reservoirs improve the potential water availability capacity, particularly in the southern basins of the continent. With this study, we expect to provide helpful insights about the current interactions of reservoirs with the river systems of the continent.
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Maavara, Taylor, Christopher T. Parsons, Christine Ridenour, Severin Stojanovic, Hans H. Dürr, Helen R. Powley, and Philippe Van Cappellen. "Global phosphorus retention by river damming." Proceedings of the National Academy of Sciences 112, no. 51 (December 7, 2015): 15603–8. http://dx.doi.org/10.1073/pnas.1511797112.
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More than 70,000 large dams have been built worldwide. With growing water stress and demand for energy, this number will continue to increase in the foreseeable future. Damming greatly modifies the ecological functioning of river systems. In particular, dam reservoirs sequester nutrient elements and, hence, reduce downstream transfer of nutrients to floodplains, lakes, wetlands, and coastal marine environments. Here, we quantify the global impact of dams on the riverine fluxes and speciation of the limiting nutrient phosphorus (P), using a mechanistic modeling approach that accounts for the in-reservoir biogeochemical transformations of P. According to the model calculations, the mass of total P (TP) trapped in reservoirs nearly doubled between 1970 and 2000, reaching 42 Gmol y−1, or 12% of the global river TP load in 2000. Because of the current surge in dam building, we project that by 2030, about 17% of the global river TP load will be sequestered in reservoir sediments. The largest projected increases in TP and reactive P (RP) retention by damming will take place in Asia and South America, especially in the Yangtze, Mekong, and Amazon drainage basins. Despite the large P retention capacity of reservoirs, the export of RP from watersheds will continue to grow unless additional measures are taken to curb anthropogenic P emissions.
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Chesterton, Owen John, Mutlu Ucuncu, and Duncan Borman. "CFD modelling for dams and reservoirs – best practice workflows, specification and review." Dams and Reservoirs 29, no. 4 (December 2019): 148–57. http://dx.doi.org/10.1680/jdare.19.00032.
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de Carvalho Barreto, Ikaro Daniel, Tatijana Stosic, Moacyr Cunha Filho, Claudio Delrieux, Vijay P. Singh, and Borko Stosic. "Complexity Analyses of Sao Francisco River Streamflow: Influence of Dams and Reservoirs." Journal of Hydrologic Engineering 25, no. 10 (October 2020): 05020036. http://dx.doi.org/10.1061/(asce)he.1943-5584.0001996.
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Hintze, Frederico, Virgínia Duro, José Carlos Carvalho, Catarina Eira, Pedro Correia Rodrigues, and José Vingada. "Influence of Reservoirs Created by Small Dams on the Activity of Bats." Acta Chiropterologica 18, no. 2 (December 1, 2016): 395. http://dx.doi.org/10.3161/15081109acc2016.18.2.007.
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REITAN, OLE, and JOSTEIN SANDVIK. "AN ASSESSMENT OF RETAINING DAMS IN HYDROPOWER RESERVOIRS FOR ENHANCING BIRD HABITAT." Regulated Rivers: Research & Management 12, no. 4-5 (July 1996): 523–34. http://dx.doi.org/10.1002/(sici)1099-1646(199607)12:4/5<523::aid-rrr409>3.0.co;2-u.
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Kim, Hwirin, Cheolhee Jang, and Sung Kim. "Conjunctive operation of river facilities for integrated water resources management in Korea." Proceedings of the International Association of Hydrological Sciences 374 (October 17, 2016): 93–99. http://dx.doi.org/10.5194/piahs-374-93-2016.
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Abstract. With the increasing trend of water-related disasters such as floods and droughts resulting from climate change, the integrated management of water resources is gaining importance recently. Korea has worked towards preventing disasters caused by floods and droughts, managing water resources efficiently through the coordinated operation of river facilities such as dams, weirs, and agricultural reservoirs. This has been pursued to enable everyone to enjoy the benefits inherent to the utilization of water resources, by preserving functional rivers, improving their utility and reducing the degradation of water quality caused by floods and droughts. At the same time, coordinated activities are being conducted in multi-purpose dams, hydro-power dams, weirs, agricultural reservoirs and water use facilities (featuring a daily water intake of over 100 000 m3 day−1) with the purpose of monitoring the management of such facilities. This is being done to ensure the protection of public interest without acting as an obstacle to sound water management practices. During Flood Season, each facilities contain flood control capacity by limited operating level which determined by the Regulation Council in advance. Dam flood discharge decisions are approved through the flood forecasting and management of Flood Control Office due to minimize flood damage for both upstream and downstream. The operational plan is implemented through the council's predetermination while dry season for adequate quantity and distribution of water.
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Naughton, George P., Christopher C. Caudill, Matthew L. Keefer, Theodore C. Bjornn, Lowell C. Stuehrenberg, and Christopher A. Peery. "Late-season mortality during migration of radio-tagged adult sockeye salmon (Oncorhynchus nerka) in the Columbia River." Canadian Journal of Fisheries and Aquatic Sciences 62, no. 1 (January 1, 2005): 30–47. http://dx.doi.org/10.1139/f04-147.
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We radio-tagged 577 adult sockeye salmon (Oncorhynchus nerka) returning to the Columbia River in 1997 to determine how migration behaviors were related to migration success in an altered river system. The probability of successful migration declined dramatically for late-entry individuals, concomitant with declines in discharge and the onset of stressful temperatures. Long dam passage times were not related to unsuccessful migration at most dams. However, when migration histories were analyzed across multiple dams or reservoirs, relatively slow migration was significantly associated with unsuccessful migration, suggesting potential cumulative effects. Median passage times at dams were rapid (7.933.4 h), although 0.2%8% of salmon took more than 5 days to pass. Reservoir passage was also rapid, averaging 36.861.3 km·day1, and appeared to compensate for slowed migration at dams. Rates observed in the unimpounded Hanford Reach suggest that total predam migration rates may have been similar to current rates. Overall, our results suggest that cumulative effects may be more important than negative effects of passage at single dams and that hydrosystem alteration of temperature regimes in the migration corridor may have an important indirect negative impact on adults.
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Turner, Sean W. D., Wenwei Xu, and Nathalie Voisin. "Inferred inflow forecast horizons guiding reservoir release decisions across the United States." Hydrology and Earth System Sciences 24, no. 3 (March 19, 2020): 1275–91. http://dx.doi.org/10.5194/hess-24-1275-2020.
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Abstract. Medium- to long-range forecasts often guide reservoir release decisions to support water management objectives, including mitigating flood and drought risks. While there is a burgeoning field of science targeted at improving forecast products and associated decision support models, data describing how and when forecasts are applied in practice remain undeveloped. This lack of knowledge may prevent hydrological modelers from developing accurate reservoir release schemes for large-scale, distributed hydrology models that are increasingly used to assess the vulnerabilities of large regions to hydrological stress. We address this issue by estimating seasonally varying, regulated inflow forecast horizons used in the operations of more than 300 dams throughout the conterminous United States (CONUS). For each dam, we take actual forward observed inflows (perfect foresight) as a proxy for forecasted flows available to the operator and then identify for each week of the year the forward horizon that best explains the release decisions taken. Resulting “horizon curves” specify for each dam the inferred inflow forecast horizon as a function of the week of the water year. These curves are analyzed for strength of evidence for contribution of medium- to long-range forecasts in decision making. We use random forest classification to estimate that approximately 80 % of large dams and reservoirs in the US (1553±50 out of 1927 dams with at least 10 Mm3 storage capacity) adopt medium- to long-range inflow forecasts to inform release decisions during at least part of the water year. Long-range forecast horizons (more than 6 weeks ahead) are detected in the operations of reservoirs located in high-elevation regions of the western US, where snowpack information likely guides the release. A simulation exercise conducted on four key western US reservoirs indicates that forecast-informed models of reservoir operations may outperform models that neglect the horizon curve – including during flood and drought conditions.
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Di Baldassarre, Giuliano, Maurizio Mazzoleni, and Maria Rusca. "The legacy of large dams in the United States." Ambio 50, no. 10 (March 8, 2021): 1798–808. http://dx.doi.org/10.1007/s13280-021-01533-x.
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AbstractThe sustainability of large dams has been questioned on several grounds. One aspect that has been less explored is that the development of dams and reservoirs often enables agricultural expansion and urban growth, which in turn increase water consumption. As such, dam development influences, while being influenced by, the spatial and temporal distribution of both supply and demand of water resources. In this paper, we explore the interplay between large dams, patterns of population growth and agricultural expansion in the United States over the past two centuries. Based on a large-scale analysis of spatial and temporal trends, we identify three distinct phases, in which different processes dominated the interplay. Then, we focus on agricultural water use in the Southwest region (Arizona, California and Nevada) and explore chicken-and-egg dynamics where water supply partly meets and partly fuels water demand. Lastly, we show that the legacy of dams in the United States consists of a lock-in condition characterized by high levels of water consumption, especially in the Southwest, which leads to severe water crises and groundwater overexploitation when droughts occur.
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Onda, Chihaya, Tetsuya Sumi, and Tsuyoshi Asahi. "Planning and Analysis of Sedimentation Countermeasures in Hydropower Dams Considering Properties of Reservoir Sedimentation." Journal of Disaster Research 13, no. 4 (August 1, 2018): 702–8. http://dx.doi.org/10.20965/jdr.2018.p0702.
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Sedimentation in hydropower reservoirs is one of the most important problems facing power generation. Many of the reservoirs our company’s dams, built in the postwar reconstruction period, have been storing up sedimentation for decades. The percentage of sedimentation is now considerable, about 9%, because of a combination of a high degree of sediment production and the river flow regime. We have been trying to excavate the sedimentation from the reservoirs to avoid aggradations of upstream riverbeds and to eliminate obstacles to intake and outlet functions. Considering sediment properties, we have carried out representative five different ways of managing reservoir sediment. At the Sakuma dam, which is comparatively large, provisional transporting inside the reservoir is the main countermeasure, but radical management will be required in the near future. At the Futatsuno dam and Taki dam, which are medium-sized, the current volume of sedimentation excavation is not sufficient to maintain the size of the reservoir, due to flow sedimentation. Sediment routing methods, such as bypassing, will therefore be urgently planned. At the Setoishi and Yambara dams, the testing of sediment sluicing or hydro-suction sediment removal systems has already started. Regarding sedimentation sluicing, we have studied the feasibility of sediment bypass tunnels and gated outlets in the dam reservoir that is unsuitable for sluicing with the existing spillway. We found that gated outlet will be effective. Although there are no quick remedies that can reduce reservoir sedimentation dramatically, there are some methods that may be suitable, considering the size, life and basin of each reservoir. Not only the technical feasibility, but also the economic advantages and ecological acceptability should be considered. To sustain reservoirs and hydropower, sedimentation should be managed effectively and adaptively, based on the specific conditions of each reservoir.
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Waligórski, Błażej, Mariusz Sojka, Joanna Jaskuła, and Mariusz Korytowski. "Analysis of the use of selected reservoirs in the Wielkopolska province." Annals of Warsaw University of Life Sciences – SGGW. Land Reclamation 50, no. 4 (December 1, 2018): 373–85. http://dx.doi.org/10.2478/sggw-2018-0029.
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Abstract The paper presents characteristics of six selected retention reservoirs located in the Wielkopolskie province, i.e. the Radzyny and Przebędowo reservoirs located near the city of Poznań, the Miedzichowo reservoir situated at the western border of the province, as well as the Stare Miasto and Jutrosin and Pakosław reservoirs, situated at the eastern and southern parts of the province, respectively. The paper also presents results of studies concerning water quality parameters in the selected reservoir of Przebędowo (at the inflow, within the reservoir and at the outflow) for the example year of 2016. The greatest water area of approx. 110 ha and at the same time the greatest capacity (2.88 million m3) at normal level damming (NLD) was found for the Radzyny reservoir on the Sama river, constructed in 2000, whereas the smallest water area (5.3 ha) and the smallest capacity (0.1 million m3) at NLD were recorded for the Miedzichowo reservoir, which was constructed in 2013. Apart from the positive aspects related to the operation of water storage reservoirs we frequently observe problems with their operation and use. In the winter periods they are mainly connected with the so-called icing, which has a negative and often destructive effect both on the condition of reservoir dams and on their banks. In turn, in the summer months a common problem in the operation of reservoirs results from obstruction from vegetation accumulated on the damming structures, which frequently reaches the dams particularly in periods characterised by high daily precipitation totals. Another common problem in terms of the operation of retention reservoirs is also related with the process of their eutrophication, connected with the influx of biogens. Analyses of selected water quality indexes for the Przebędowo reservoir showed, particularly in relation to nitrates and nitrites, their higher values at the inflow to the reservoir, indicating a considerable effect of land use in adjacent areas primarily in terms of fertilisation and the resulting runoff of biogens to the watercourse supplying the reservoir.
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Wang, Fangtian, Ningning Liang, and Gang Li. "Damage and Failure Evolution Mechanism for Coal Pillar Dams Affected by Water Immersion in Underground Reservoirs." Geofluids 2019 (January 6, 2019): 1–12. http://dx.doi.org/10.1155/2019/2985691.
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In coal mines, underground reservoir systems can increase the availability of water and are an effective technical approach for the protection and utilization of water resources. The stability of coal pillar dams is the key factor in the safety and stability of these underground water storage systems. However, coal pillar dams must operate in complex environments that combine dynamic-static superimposed stress fields and water immersion; moreover, coal pillar dams subjected to both stress and seepage are more susceptible to damage and even collapse. In this study, a seepage-stress coupling model of a coal pillar dam was constructed using the Universal Distinct Element Code (UDEC) simulation software. This model provides a platform for analyzing the characteristics of fracture development in surrounding rock in active mines and the coupled development of crack fields and seepage fields in coal pillar dams. Methods were developed for (1) calculating the water content for the coal pillar dam numerical simulation model and (2) reducing water immersion weakening. The maximum seepage width of a coal pillar dam subjected to water immersion was obtained, and a damage and failure evolution mechanism for coal pillar dams experiencing flooding was developed. The results provide a scientific basis for enhancing the stability control of coal pillar dams and are of great significance for realizing water conservation in coal mines.
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Halbedel, S., and M. Koschorreck. "Different regulation of CO<sub>2</sub> emission from streams and lakes." Biogeosciences Discussions 10, no. 6 (June 20, 2013): 10021–53. http://dx.doi.org/10.5194/bgd-10-10021-2013.
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Abstract. It has become more and more evident that CO2 emission (FCO2) from freshwater systems is an important part in the global carbon cycle. Only few studies addressed the different mechanisms regulating FCO2 from lotic and lentic systems. In a comparative study we investigated how different biogeochemical and physical factors can affect FCO2 from streams and reservoirs. We examined the seasonal variability in CO2 concentrations and emissions from four streams and two pre-dams of a large drinking water reservoir located in the same catchment, and compared them with parallel measured environmental factors. All streams generally were supersaturated with CO2 over the whole year, while both reservoirs where CO2 sinks during summer stratification and sources after circulation. FCO2 from streams ranged from 23 to 355 mmol m–2 d–1 and exceeded the fluxes from the reservoirs (–24 to 97 mmol m–2 d–1). Both the generally high piston velocity (k) and CO2 oversaturation were responsible for the higher FCO2 from streams in comparison to lakes. In both, streams and reservoirs FCO2 was mainly controlled by the CO2 concentration (r = 0.86 for dams, r = 0.90 for streams), which was clearly affected by metabolism and nutrients in both systems. Besides CO2 concentration, also physical factors control FCO2 in lakes and streams. During stratification FCO2 in both pre-dams was controlled by primary production in the epilimnion, which led to a decrease of FCO2. During circulation when CO2 from the hypolimnion was mixed with the epilimnion and the organic matter mineralisation was more relevant, FCO2 increased. FCO2 from streams was physically controlled especially by geomorphological and hydrological factors regulating k, which is less relevant in low wind lakes. We developed a schematic model describing the role of the different regulation mechanism on FCO2 from streams and lakes. Taken together, FCO2 is generally mostly controlled by CO2 concentration in the surface water. Lake stratification is a very important factor regulating FCO2 from lakes via controlling CO2 concentration and metabolism. But FCO2 in heterotrophic streams is generally higher. The higher k values are responsible for the comparable high FCO2. On a Central European landscape scale CO2 emission from streams was more relevant than the CO2 flux from standing waters.
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Mu, Mengfei, Qiuhong Tang, Songjun Han, Xiaomang Liu, and Huijuan Cui. "Using GRanD Database and Surface Water Data to Constrain Area–Storage Curve of Reservoirs." Water 12, no. 5 (April 27, 2020): 1242. http://dx.doi.org/10.3390/w12051242.
Full textAbstract:
Basic information on global reservoirs is well documented in databases such as GRanD (Global Reservoir and Dam) and ICOLD (International Commission on Large Dams). However, though playing a critical role in estimating reservoir storage variations from remote sensing or hydrological models, area–storage curves of reservoirs are not conveniently obtained nor publicly shared. In this paper, we combine the GRanD database and Landsat-based global surface water extent (GSW) data to derive area–storage curves of reservoirs. The reported storage capacity in the GRanD database and water surface area from GSW data were used to constrain the area–storage curve. The proposed method has the potential to derive area–storage curves of reservoirs larger than 1 km2 archived in the GRanD database. The derived curves are validated with in situ reservoir data collected in US and China, and the results show that in situ records are well captured by the derived curves both in large and small reservoirs with various shapes. The derived area–storage curves could be employed to advance global monitoring or modeling of reservoir storage dynamics.