Dam safety

We regulate more than 1,100 dams in Washington. Safety is our priority and we have rigorous procedures in place to protect people and property located downstream of dams.

Through plan reviews and construction inspections, we help ensure dams are properly designed and constructed. We also inspect existing dams to ensure proper operation and maintenance. In Washington, a dam owner is legally responsible to maintain, repair, or operate their dam in a safe and proper manner.

Our work includes:

  • Emergency response services
  • Construction services
  • Inspection services

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.

State statutes

Administrative rules

Policies