Prado Reservoir is a

reservoir A reservoir (; ) is an enlarged lake behind a dam, usually built to water storage, store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of wa ...

in northwestern

Riverside County Riverside County is a county located in the southern portion of the U.S. state of California. As of the 2020 census, its population was 2,418,185, making it the fourth-most populous county in California and the 10th-most populous in the Unit ...

and southwestern

San Bernardino County San Bernardino County ( ), officially the County of San Bernardino and sometimes abbreviated as S.B. County, is a county located in the southern portion of the U.S. state of California, and is located within the Inland Empire area. As of th ...

, a couple of miles west of the city of

Corona Corona (from the Latin for 'crown') most commonly refers to: * Stellar corona, the outer atmosphere of the Sun or another star * Corona (beer), a Mexican beer * Corona, informal term for the coronavirus or disease responsible for the COVID-19 ...

, in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. The reservoir has a capacity of and is formed by Prado Dam on the

Santa Ana River The Santa Ana River is the largest river entirely within Southern California in the United States. It rises in the San Bernardino Mountains and flows for most of its length through San Bernardino County, California, San Bernardino and Riversid ...

. The

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...

is composed of rock-fill and has a height of 106 feet (32 m) above the original streambed. It was built on the upper end of the Lower Santa Ana River Canyon, where there is a natural constriction in the river. It is below 2,255 square miles (5,840 km²) of the Santa Ana River

watershed Watershed may refer to: Hydrology * Drainage divide, the line that separates neighbouring drainage basins * Drainage basin, an area of land where surface water converges (North American usage) Music * Watershed Music Festival, an annual country ...

. The dam was built by the

United States Army Corps of Engineers The United States Army Corps of Engineers (USACE) is the military engineering branch of the United States Army. A direct reporting unit (DRU), it has three primary mission areas: Engineer Regiment, military construction, and civil wo ...

and was completed in 1941. Prado Dam and Prado Reservoir provide

flood A flood is an overflow of water (list of non-water floods, or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant con ...

control and

water conservation Water conservation aims to sustainably manage the natural resource of fresh water, protect the hydrosphere, and meet current and future human demand. Water conservation makes it possible to avoid water scarcity. It covers all the policies, strateg ...

. Their operation is coordinated with the facilities upstream. Prado Reservoir is not a storage reservoir, so water is released as quickly as possible while still allowing for

groundwater recharge Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer. This process usually occurs in ...

. When the water level reaches the top of the buffer pool, whose size changes depending on time of year, water is released at the maximum rate that the downstream channel will safely allow. As of 2006, the capacity of the channel is per second (140 m³/s), but channelization will eventually increase the capacity to per second (850 m³/s). During flood season, the buffer pool only has a capacity of , while outside of flood season, the capacity increases to . Since this is 2.3 and 7.1 percent of the reservoir's total capacity, respectively, the reservoir is usually fairly empty.

References

United States Army Corps of Engineers - Prado Dam
* United States Army Corps of Engineers - Prado Dam Brochure Reservoirs in Riverside County, California Reservoirs in San Bernardino County, California Reservoirs in California Reservoirs in Southern California {{RiversideCountyCA-geo-stub

See also

References