DEFINITION
It is an artificial lake where water is collected and kept in quantity for use. Reservoirs can be used in a number of ways to control how water flows through downstream waterways. Reservoirs often provide for recreational uses. Most reservoirs are built for a civic purpose, but still allow fishing, boating, and other activities. Still others can be used to store water, to be used for drinking (either by animals or humans) or fire protection

AKA
Similar or related to an Ab Anbar, drainage basin, mill pond and spillway.
cistern

PERFORMANCE CRITERIA
- Water quality in reservoirs is determined by the quality of water flowing into the reservoir and in-lake processes. Water flowing in can transport materials such as nutrients, sediments and other contaminants. These can then be affected by in-lake processes such as settling and biochemical action.
- Quantity of water - Quantity of water in the reservoir depends on three things: inflow, seepage conditions (either in or out) and outflow.
Over the years, man-made reservoirs have been decried for lessening biological diversity (i.e. in Tennessee, the Tellico Reservoir & Dam led to the demise of the snail darter) and inudating cultural and archelogically important sites(in China, the Three Gorges Dam & Reservoir inudated many small villages and archeological sites; in Egypt, Lake Nassar (resulting from the Aswan Dam) flooded fertile agricultural land and resulted in the relocation of Temple of Abu Simel).

ILLUSTRATION

The Jhonghua Dam on the Dahan River in Taoyuan County, Taiwan


Diagram of a reservoir showing temperature profile. Curtesy of Water Quality,HSC Biology.

CASE STUDIES
Lake Kariba, the largest reservoir in the world.

ADDITIONAL RESOURCES
Department of Water Resources "Reservoir information"
The Jaqueline Kennedy Onassis Reservoir@ http://www.centralpark.com/pages/attractions/reservoir.html