Potholes State Park is a 773-acre public recreation area located 13 miles from Moses Lake in Grant County, Washington, on the southern shore of Potholes Reservoir.

The state park was created after the O'Sullivan Dam was built in 1949. The park has 6,000 feet of shoreline with facilities for camping, boating, swimming, hiking, fishing, and other water fun.

The Potholes are a geologic feature, a series of Ice Age depressions in the earth carved by flood. Combined with the dynamics of the O’Sullivan Dam, they created hundreds of small islands surrounded by tiny “pothole” lakes.

The little lakes make up half the O’Sullivan Reservoir. Potholes State Park is located on its other side, where the lake is deeper and more suitable for to boaters, fishers and swimmers.

Address: 6762 Highway 262 East, 6762 WA-262, Othello, WA 99344, Phone: 509-346-2759

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