reservoir (redirected from Reservoirs)

reservoir (rĕz`əvôr, -vwär), storage tank or wholly or partly artificial lake for storing water. Building an embankment or dam to preserve a supply of water for irrigation is an ancient practice; India and Egypt have many old and large reservoirs. In building artificial lakes for a municipal water supply it is necessary to consider all the aspects of a catchment area, including the amount and distribution of rainfall, evaporation, runoff, soil or rock conditions, and elevation (for its effect upon precipitation and upon the pressure in the conducting pipes). The ground of the reservoir may be naturally impervious enough to prevent excessive seepage, or a clay or other lining may have to be built. The embankments or retaining walls may be of earth, loose rock, or masonry. Earth forms a good embankment but must be sealed by a core of clay, and the face must be covered with masonry or a similar substance to prevent erosion. Distributing reservoirs in towns are sometimes built of masonry or of reinforced concrete. They serve to cope with fluctuations of demand and with interruptions of supply from the source. Reservoirs are also built on the headstreams of or along the courses of rivers to aid in flood control, on canals to maintain water level for navigation, and to ensure water supply for hydroelectric plants. Some reservoirs are built on the tributaries of large rivers to act as catch basins for silt. In addition to seepage, the major loss of water from a reservoir is by evaporation; chemicals that form a film on a water surface are used to minimize such losses. Covered tanks made of prestressed concrete are used for limited local water supply.

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reservoir

1. a natural or artificial lake or large tank used for collecting and storing water, esp for community water supplies or irrigation

2. Biology a vacuole or cavity in an organism, containing a secretion or some other fluid

3. Anatomy another name for cisterna

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reservoir [′rez·əv‚wär]

(civil engineering)

A pond or lake built for storage of water, usually by the construction of a dam across a river.

(geology)

A subsurface accumulation of crude oil or natural gas under adequate trap conditions.

An area covered by névé where snow collects to form a glacier.

A space within the earth that is occupied by magma.

(science and technology)

A container for storage of a liquid material, for example, a tank.

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Reservoir

A place or containment area where water is stored. Where large volumes of water are to be stored, reservoirs usually are created by the construction of a dam across a flowing stream. When water occurs naturally in streams, it is sometimes not available when needed. Reservoirs solve this problem by capturing water and making it available at later times. See Dam

In addition to large reservoirs, many small reservoirs are in service. These include varieties of farm ponds, regulating lakes, and small industrial or recreational facilities. In some regions, small ponds are called tanks. Small reservoirs can have important cumulative effects in rural regions

Reservoirs can be developed for single or multiple purposes, such as to supply water for people and cities, to provide irrigation water, to lift water levels to make navigation possible on streams, and to generate electricity.

Another purpose of reservoirs is to control floods by providing empty spaces for flood waters to fill, thereby diminishing the rate of flow and water depth downstream of the reservoir.

Reservoirs also provide for environmental uses of water by providing water to sustain fisheries and meet other fish and wildlife needs, or to improve water quality by providing dilution water when it is needed in downstream sections of rivers. Reservoirs may also have esthetic and recreational value, providing boating, swimming, fishing, rafting, hiking, viewing, photography, and general enjoyment of nature. See Pumped storage, River engineering, Water supply engineering