Pyramid Dam is a dam on

Piru Creek Piru Creek is a major stream, about long, in northern Los Angeles County and eastern Ventura County, California. It is a tributary of the Santa Clara River, the largest stream system in Southern California that is still relatively natural. Th ...

located in northern Los Angeles County, north of

Castaic Castaic () ( Chumash: ''Kaštiq''; Spanish: ''Castéc'') is an unincorporated community in the northwestern part of Los Angeles County, California. As of the 2010 census it had a population of 19,015. For statistical purposes the Census Bure ...

and south of Gorman. Its reservoir, Pyramid Lake, stores water from the West Branch

California Aqueduct The Governor Edmund G. Brown California Aqueduct is a system of canals, tunnels, and pipelines that conveys water collected from the Sierra Nevada Mountains and valleys of Northern and Central California to Southern California. Named after Cali ...

for

Ventura County Ventura County () is a County (United States), county in Southern California, the southern part of the U.S. state of California. As of the 2020 United States Census, 2020 census, the population was 843,843. The largest city is Oxnard, California ...

and

Los Angeles County Los Angeles County, officially the County of Los Angeles, and sometimes abbreviated as L.A. County, is the most populous county in the United States and in the U.S. state of California, with 9,861,224 residents estimated as of 2022. It is th ...

. They are smaller than Castaic Dam and

Lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much lar ...

, the other artificial water storage facility in the area, to the south.

Funding and construction

Construction of the dam was made possible by California voter approval in 1960 of the California Aqueduct project, also referred to as the Feather River project (the source of the water in the northern part of the state north of Auburn). State bonds were issued to finance the project. Pyramid Dam, which first began construction in 1968, is 386 feet (118 m) high. It lies directly behind the mountain rock giving the dam and lake its name - Pyramid Cut - which before the Ridge Route Alternate (later signed as

U.S. Route 99 U.S. Route 99 (US 99) was a main north–south United States Numbered Highway on the West Coast of the United States until 1964, running from Calexico, California, on the US–Mexico border to Blaine, Washington, on the U.S.-Canada border ...

) was built through the area in the 1931 to 1933 time period, was just another ordinary mountain. The highway construction of the Ridge Route Alternate caused this mountain to have part of its mass "shaved" off - reduced in size - and after the work to accommodate highway traffic was finished, the shape of the cut was found to resemble a pyramid, and hence the name.

Statistics

Pyramid Dam holds of water, covering an area of . Its maximum capacity is of water. The lake behind the dam, shaped like a ''

Triceratops ''Triceratops'' ( ; ) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is ...

tooth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

, has been used for boating, swimming and camping since 1974. The dam and lake were built by the state of

California Department of Water Resources The California Department of Water Resources (DWR) is part of the California Natural Resources Agency and is responsible for the management and regulation of the State of California's water usage. The department was created in 1956 by Governor ...

(DWR), who maintains them today. The water stored there serves residents, businesses and farmers in

and LA County.

US 99

During the construction of Pyramid Dam, US 99 vehicle traffic was rerouted to

Interstate 5 Interstate 5 (I-5) is the main north–south Interstate Highway on the West Coast of the United States, running largely parallel to the Pacific coast of the contiguous U.S. from Mexico to Canada. It travels through the states of Calif ...

beginning in 1968. In the 1968-9 time period, motorists could still drive US 99 from Violin Summit to Hungry Valley Road (since renamed Smokey Bear Road). After completion of the dam in 1970 Feather River water began to fill the area behind the dam, a plan conceived of even before the construction of the Ridge Route Alternate. By 1972 the Ridge Route Alternate was fully submerged under the lake's water. Since then, its southern border with the lake continues to serve as a boat ramp. The lake's northern border portion of US 99 is closed to motorists.

Notes

External links

*
US 99 - Piru Gorge: Pyramid Rock and Dam
{{LA County dams Dams completed in 1970 Dams in California California Department of Water Resources dams Geography of Los Angeles County, California

Funding and construction

Statistics

US 99

See also

Notes

External links