Nimbus Dam

Nimbus Dam
Country	United States
Location	Sacramento County, California
Coordinates	38°38′10″N 121°13′11″W / 38.636095°N 121.219806°W / 38.636095; -121.219806,inline
Status	Operational
Construction began	1952; 72 years ago (1952)
Opening date	1955; 69 years ago (1955)
Owner(s)	Bureau of Reclamation
Dam and spillways
Impounds	American River
Height	87 ft (27 m)
Length	1,093 ft (333 m)
Elevation at crest	132 ft (40 m)
Width (crest)	28 ft (8.5 m)
Width (base)	135 ft (41 m)
Dam volume	8,760 acre-feet (10,810 dam3)
Reservoir
Creates	Lake Natoma
Catchment area	1,898 sq mi (4,920 km2)
Power Station
Installed capacity	13.5 MW
Annual generation	51,097,000 KWh

The Nimbus Dam is a base load hydroelectric dam on the American River near Folsom, California. Approximately 8,700 acre-feet (10,700 dam³) of water is retained by the dam. It is responsible for the impoundment of water from the American River to create the Lake Natoma reservoir. The dam stands 87 feet and spans 1,093 feet. The Nimbus powerplant consists of two generators. Each generator produces enough electrical power to power over 200,000 100-watt light bulbs, about 15,500 kilowatts of electrical power.^[1] Nimbus Dam consists of 18 radial gates, each with their own gate bays. These 18 gates today are the ones that were completed in 1955 along with the rest of the dam. Of the eighteen gates, four of them have had their coating system replaced. This protects the gates from a faster rate of corrosion. The other fourteen gates have the original coating.^[2]

As part of the Central Valley Project (CVP), a federal water project that provides irrigation and municipal water to much of California's Central Valley, it was authorized in 1949 as a regulating reservoir for Folsom Dam, and a diversion pool for the Folsom South Canal.^[3][4] Construction began in 1952, and it opened in 1955.