Sibley

About Sibley

The primary purpose of Sibley is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Usda Fs (federal). It impounds the Prune Creek near Dayton.

The dam stands 35 feet tall and stretches 420 feet across, creates a reservoir covering 34 acres, has a maximum storage capacity of 635 acre-feet, and collects water from a drainage area of 5 square miles. Completed in 1938, 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. An emergency action plan is in place for this dam. The most recent inspection on record was 08/27/2020.

At 35 feet, this dam is taller than 82% 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 Wyoming 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.