Potholes State Park

Potholes State Park is a protected landscape surrounding a reservoir in the high desert east of the Cascade Range. The park spans roughly 640 acres and combines open water, marsh vegetation, and semi-arid terrain along an extended shoreline.

The reservoir was created in 1949 when the O'Sullivan Dam was built to store water for irrigation and hydroelectric power. The park was established afterward to provide public access and recreational opportunities around this water resource.

The park serves as a gathering place for anglers and boaters who value time on the water and in nature. These recreational traditions have shaped how people use this landscape throughout the year.

The park is open from sunrise to sunset and can be explored from the shoreline or by boat. A Discover Pass is required for parking and access to facilities.

Water levels in the reservoir fluctuate significantly between spring and fall, revealing different landscapes depending on the season. These changes affect which wildlife species are present and visible throughout the year.

Location: Grant County

Operator: Washington State Parks and Recreation Commission

Website: https://parks.wa.gov/568/Potholes

GPS coordinates: 46.97944,-119.35083

Latest update: December 9, 2025 18:42