American River

The American River in California is known for its whitewater rapids, and as the location of Sutter's Mill (where gold was found, leading to the California Gold Rush). It runs from the Sierra Nevada mountains through Sacramento and flows into the Sacramento River on its way to San Francisco Bay.
The American River is divided into the North, Middle, South and Silver Forks before they reach their confluence in Folsom Lake and are popular for their verdant canyons, fishing and white water rafting. Below Folsom Lake, the river passes through an urbanized area but is buffered by a riparian park that runs from Folsom Lake to the river's confluence with the Sacramento River.
The American River and its tributaries are extensively dammed and diverted for hydroelectricity production. The five power plants on the Middle Fork are owned by the Placer County Water Agency (PCWA) and the Sacramento Municipal Utility District (SMUD) owns eight plants on the South Fork. The SMUD plants are run on a peaking basis, although reservoir flood control capacity and minimum flow requirements impose some constraints on their operation. PG&E owns the Chili Bar power plant on the South Fork downstream from SMUD's plants.