The Upper American River Project (UARP) is a

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

system operated by the Sacramento Municipal Utility District (SMUD) of

Sacramento Sacramento ( or ; ; ) is the capital city of the U.S. state of California and the seat of Sacramento County. Located at the confluence of the Sacramento and American Rivers in Northern California's Sacramento Valley, Sacramento's 2020 p ...

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 ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. The system consists of 11 dams and eight powerhouses that tap the upper tributaries of the

American River The American River is a List of rivers of California, river in California that runs from the Sierra Nevada (U.S.), Sierra Nevada mountain range to its confluence with the Sacramento River in downtown Sacramento. Via the Sacramento River, it ...

drainage in the

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

for power generation. Total installed capacity is over 687 MW, producing 1.8 billion KWh annually, enough for 20 percent of the city's electricity needs. The project mainly utilizes water from the South Fork American River and its tributaries, although some water is drawn from the Rubicon River, a tributary of the Middle Fork American River. Project dams provide water storage of about and a total

hydraulic head Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a. It is usually meas ...

of from the highest reservoir to the lowest powerplant outflow.

History

The UARP was authorized on August 28, 1957 by an act of the

Federal Power Commission The Federal Power Commission (FPC) was an independent commission of the United States government, originally organized on June 23, 1930, with five members nominated by the president and confirmed by the Senate. The FPC was originally created in ...

. SMUD began construction in September of that year, and the first power generation from UARP came online at Jaybird Powerhouse on May 1, 1961. Most of the project facilities were completed by 1967. The Loon Lake Powerhouse was completed in 1971, and Jones Fork Powerhouse was finished in 1985. Environmental impacts include the prevention of fish passage by the project's dams, which segment parts of the upper South Fork American River, the Rubicon River and their tributaries.

Overview

Water is diverted from the Rubicon River to a storage reservoir, Loon Lake, from which it is released through the Loon Lake Powerhouse to Gerle Creek. This water is intercepted and diverted into Silver Creek, a tributary of the South Fork American River, flowing through the Robbs Peak Powerhouse into Union Valley Reservoir, the project's principal reservoir. Water from Ice House Reservoir also enters Union Valley via the Jones Fork Powerhouse. From Union Valley, water flows through the Union Valley Powerhouse to Junction Reservoir, then through Jaybird Powerhouse to Camino Reservoir, both on Silver Creek. The water then enters a penstock that feeds the Camino Powerhouse above Slab Creek Reservoir on the South Fork American River. From there, water is sent through a final tunnel to White Rock Powerhouse, located on the upper end of Chili Bar Reservoir also on the South Fork.

List of facilities

† indicates a diversion dam

References

{{authority control American River (California) Hydroelectric power plants in California Sacramento Municipal Utility District Eldorado National Forest