Lake Britton Reservoir is filled by a dam at Pit River and is filled by The Pit, Cayton Creek, Clark Creek,
Hat Creek, and Burney Creek. It covers roughly seven miles of the Pit River's channel. The lake is maintained by P G & E as a source of hydroelectric energy and for recreation.
While the Park only encompasses a small part of the lake, it does feature a very family-friendly beach as well as a boat ramp, docks and rentals. The fishing is good and so is the waterplay. Popular sports include skiing and wakeboarding, tubing, kayaking, swimming and fishing. The park features two very nice picnic areas near the lake. One at the boat ramp and one at Pioneer Cove which requires a hike.
Additional camping is available outside the park on the north shore of the lake at either of two small campgrounds operated by P G & E. Both of these also feature beaches and boat ramps.

Resources: California Department of Water Resources, P.G.&E. Pit River Rec. Page

Here is a link to the google images for the Lake