Lake Corsica Dam

About Lake Corsica Dam

The primary purpose of Lake Corsica Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Douglas County (local government). It impounds the Choteau Creek.

The dam stands 32 feet tall and stretches 720 feet across, creates a reservoir covering 116 acres, has a maximum storage capacity of 2,020 acre-feet, and collects water from a drainage area of 81 square miles. Completed in 1939, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 08/15/2022.

At 32 feet, this dam is taller than 76% of dams nationwide.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The South Dakota dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.