About the dams we regulate
The dams we regulate:
- Store at least 10 acre-feet (or 3.2 million gallons) of water
- Are mostly under 50 feet tall
- Are mostly earthen-fill dams
- Are mostly privately-owned
- Were mostly built for irrigation or recreational purposes
Thirty-seven percent of the dams we regulate are considered "high hazard" or "significant hazard" because they are located above populated areas. We generally do not regulate hydroelectric project dams.
Who else regulates dams?
While we regulate the majority of dams in Washington, we are not the only regulator. There are 145 dams that are owned and/or regulated by one or more of the following government entities:
- Federal Energy Regulatory Commission
- Bureau of Reclamation
- U.S. Army Corps of Engineers
- U.S. Department of the Interior
Laws & regulations
Our dam safety work is governed by the Revised Code of Washington (RCW) and Washington Administrative Code (WAC). Policies are used to ensure consistency in the administration of laws and regulations.