Reservoir

Reservoir, body of water or receptacle used for storing large supplies of water. Reservoirs are most often manmade lakes, caused by damming up rivers and streams or dredging a basin into a flat stretch of land; water towers and holding tanks atop buildings are also reservoirs. Whether manmade or natural lakes, reservoirs usually supply drinking water to cities and towns, and are used to irrigate, supply power, or control flooding. Water is drawn from reservoirs through pipes (aqueducts) and in some cases is pumped hundreds of miles away.