East Park Dam, which forms East Park Reservoir, is part of the Orland Project. Completed in 1910, the dam was authorized under the Reclamation Act of June 17, 1902 and stores irrigation waters diverted and impounded from Stony Creek, Little Stony Creek, Squaw Creek, and Little Indian Creek. East Park Reservoir measures 2.7 miles in length and encompasses an area of 1,820 acres. The reservoir has a total capacity of 52,000 acre-feet. There are 25 miles of shoreline, ten miles of which are available for recreation.
East Park Reservoir is in Colusa County, California, and lies on the west side of the Sacramento Valley, in the foothills of the coastal mountain ranges. The small town of Stonyford lies a few miles northwest of the reservoir, and the smaller community of Lodoga is near its southern boundary. Interstate 5, the main north-south transportation corridor in northern California, is approximately 15 miles east of the reservoir. Narrow roads connect the communities of Williams, Maxwell, and Willows to East Park, all of which are located on Interstate 5. Access to the west shore is via a one-lane paved road.
Total land area around the reservoir is 2,468 acres. Approximately 1,630 acres at the reservoir is used by the public for recreation, including boating, fishing, and bird watching. There are approximately 200 acres of wetlands and 1,200 acres of upland wildlife areas. Cattle graze on approximately 1,900 acres during the off-season. Currently, the reservoir is open to the public approximately April through the end of September.