• River: Feather River
• Length: 167 Miles
• Surface Area: 15,810 Acres
• Volume: 3,537,577 Acre Feet
• Drainage Area: 3,624 Square Miles
Lake Oroville, is a reservoir formed by the Oroville Dam impounding the Feather River, located in Butte County, northern California. The lake is situated 5 miles northeast of the city of Oroville, within the Lake Oroville State Recreation Area, in the western foothills of the Sierra Nevada.
At over 3,500,000 acre feet, it is the second-largest reservoir in California, after Shasta Lake. The lake is fed by the North Fork, Middle Fork, West Branch and South Forks of the Feather River.
The lake has an unmarked 9,000 ft diameter landing area for seaplanes. The lake is a popular nationally renowned bass fishing location, while coho salmon are stocked from the Feather River Fish Hatchery.
Prior to impoundment by the Oroville Dam, the current main basin of Lake Oroville was the location of the confluence of the North Fork Feather River with the Feather River and the now-inundated towns of Bidwell and Land. Completed in 1968, Oroville Dam is an earthen dam and is the tallest dam located in the United States, measuring over 770 feet high and 6,920 feet across. The dam was the largest earth-fill dam in the world until succeeded by Aswan High Dam in Egypt. It was built by the California Department of Water Resources as part of the California State Water Project. The dam houses the Edward Hyatt Powerplant, an underground hydro-electric plant that was completed in 1967. Six generators are used to provide a maximum generating capacity of 819 MVA.
The Hyatt Generating-Pumping Plant source water for the Feather River is released from two discharge tunnels at up to 17,500 cu ft/s during peak demand and "little or no release the remainder of the day". The power plant also routinely draws up to 5,610 cu ft/s of Feather River water for "pumpback" into Lake Oroville. Hyatt releases are stored in the 4.40 miles serpentine river channel (Thermalito Diversion Pool) which extends from the river's source to the Thermalito Diversion Dam.