Reservoirs impoundment

The main economic use of the Ebro River has been hydropower and irrigation. The Ebro River has 187 reservoirs impounding 57% of the mean annual runoff. Such a large number of reservoirs deeply alter the fluvial regimes. None of the major dams in the basin was built for flood control, but the sheer volume of the impoundments affects the flood magnitude. Diverted water is used mainly for hydropower production and for irrigation. All the dams were constructed during the twentieth century,... 

There are 318 river gauging stations within the Ebro basin [80]. Around 60 of these monitor natural flow regimes and are typically located around the edges of the basin in the medium to higher reaches of the tributary rivers [8], Others are located on rivers whose streamflow has been altered by reservoirs (see [9] for a review of historical water policy in Spain). In total, 187 reservoirs impound 57% of the mean annual runoff [10]. As an example, annual discharge measured... 

Milltown reservoir impounds about 180 acres of water at the confluence of the Blackfoot and Clark Fork rivers (Figure 3). The Clark Fork River at that... 

As can be seen from Figure 7, landslide stability status changes in accordance with the reservoir water level. With the reservoir impounding, the water level rises from elevation 485 m to 510 m,... 

Other sources of earthquakes are induced earthquakes, caused by reservoir impoundment, pumping into deep wells, fluid extraction, volcanic eruption, gas bursts, geysers, mining, underground nuclear blasts, depletion of oil and gas reservoirs, the collapse of underground mines and nuclear bomb testing. The hypocent-ers of these earthquakes are at a relatively shallow depth. 

Abernathy AR, Cumbie PM. 1977. Mercury accumulation by largemouth bass Micropterus salmoides) in recently impounded reservoirs. Bull Environ Contam Toxicol 17 595-602. 

Anderson, M.R., D.A. Scruton, U.P. Williams, and J.F. Payne. 1995. Mercury in fish in the Smallwood Reservoir, Labrador, twenty one years after impoundment. Water Air Soil Pollut. 80 927-930. Andersson, P., H. Borg, and P. Karrhage. 1995. Mercury in fish muscle in acidified and limed lakes. Water Air Soil Pollut. 80 889-892. 

Jackson, T.A. 1988. The mercury problem in recently formed reservoirs of northern Manitoba (Canada) effects of impoundment and other factors on the production of methyl mercury by microorganisms in sediments. Canad. Jour. Fish. Aquat. Sci. 45 97-121. 

Significant releases of petroleum hydrocarbons from unlined surface impoundments in oil fields have also been reported as far back as the early 1900s. One unlined surface oil reservoir located in the Kem River field, southern California, had a reported fluid loss on the order of 500,000 barrels. Excavated pits showed oil penetration to depths exceeding 20 ft. Another loss of 1 million barrels over a period of 6 years occurred from another unlined reservoir in the same field, although some of this loss was through evaporation. 

Reservoirs can be either natural or man-made. Natural reservoirs can include lakes or other contained water bodies, while man-made reservoirs usually consist of some sort of engineered structure, such as a tank or other impoundment structure. In addition to the water containment structure itself, reservoir systems may also include associated water treatment and distribution equipment, including intakes, pumps, pump houses, piping systems, chemical treatment and chemical storage areas, and so forth. 

Dams are individually unique stractures and dam constraction represents the largest stmctures of basic infrastructure in all nations. The construction of a dam and power plant, along with the impounding of a reservoir, creates certain social and physical changes. The total installed capacity of HP is 640 000 MW (26% of the theoretical potential), generating an estimated 2380 TWh/year in the world, producing nearly 20% of the total global supply of electricity. 

Early in the history of mining and smelting in the Clark Fork basin, reservoirs were the first recipients of contaminants. These reservoirs were built to retain milling wastes for secondary recovery of metals, to limit effluent moving downstream into the Clark Fork River, and to serve as hydroelectric impoundments. They now make up a vast array of tailings ponds in the headwaters of the Clark Fork River and large downstream lakes that act as sinks and sources for contaminants to surface and groundwater in the basin. 

Differences in the hydrologic characteristics for the upper and lower portions of Twelve Mile Creek and for Lake Hartwell are believed to have a significant effect on physiochemical and biochemical weathering processes. The upper portion of Twelve Mile Creek (0-32 km) is characterized by relatively shallow waters and high water velocities. In the lower portion (32-39 km), the creek deepens and widens because of the impoundment of Lake Hartwell. Water velocities are much slower in this portion of the creek, and a significant portion of the solids load is deposited in the sediments. Flow from Twelve Mile Creek eventually enters the top of Lake Hartwell, where it mixes with uncontaminated waters from the Keowee River. The waters then move slowly down this 50-km-long reservoir toward the Hartwell Dam. 

Three of the 28280 assessed systems had multiyear average concentrations above 3.0ppb for the 8-year period (Table 29.5). Each obtained raw water from an impounded (reservoir) surface water source. The multiyear average for atrazine concentrations in these systems ranged from 3.30 to 3.41 ppb. 

This product may not be mixed or loaded within 50 ft of intermittent streams and rivers, natural or impounded lakes and reservoirs. 

Storage to be provided in impounding reservoirs for municipal water supply. Ibid., 77 1539-1640. 

In general, reservoir sediments can be dated by several techniques. In one technique, the sediment surface is dated by the time of coring while in the other the date is derived from a visual inspection of the cored sediment column which often penetrates the pre-impoundment surface. The primary... 

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