North Fork American River
The North Fork American River is the longest branch of the American River in Northern California. It is long from its source at the crest of the Sierra Nevada, near Lake Tahoe, to its mouth at Folsom Lake northeast of Sacramento. Prior to the construction of Folsom Dam the river was about longer making for a total length of .
American River
Eight hydroelectric plants on the South Fork are operated by Sacramento Municipal Utility District (SMUD) as the Upper American River Project. These plants are fed by a series of reservoirs including Loon Lake, Ice House Reservoir and Union Valley Reservoir. With the exception of Folsom Lake, Union Valley is the largest in the American River watershed, storing of water. The Upper American River Project produces 1.8 billion kilowatt hours in an average year, enough for about 20 percent of Sacramento's electricity needs. The SMUD plants are run on a peaking basis, although recreational boating and environmental flow requirements constrain their operation slightly.