Wetland Regulations

In Washington, wetlands are protected by several laws overseen by state, local, and federal agencies as well as tribes. We have the authority to regulate wetlands under the state Water Pollution Control Act and the Shoreline Management Act. We use the State Environmental Policy Act (SEPA) process to identify potential wetland-related concerns early in the environmental review and permitting process. We also have authority to review and approve projects under Section 401 of the federal Clean Water Act.

Wetland regulations can vary in how they apply to different types of wetlands and activities that can impact wetlands. The best way to determine when laws and rules apply to a particular wetland or activity is to consult with all appropriate agencies.

Ecology is the lead wetland regulatory agency within the state. At the local level, contact your city or county planning department. At the federal level, contact the U.S. Army Corps of Engineers (Corps). Tribes and the U.S. Environmental Protection Agency (EPA) also play an important role in wetland regulations when projects affecting reservation land, trust lands, cultural resources, traditional cultural properties, and tribal “usual and accustomed” areas beyond reservation boundaries.

State agencies

We serve as the lead state agency for wetland regulations, and work with other state agencies and local authorities to support regulatory and non-regulatory wetland protection in the state. If you have a project with the potential to impact wetlands, see our state regulations and applicant resources webpage. 

We have authority to regulate wetlands through two state laws: the state Water Pollution Control Act and the Shoreline Management Act. We also are the implementing agency for Section 401 of the federal Clean Water Act and federal Coastal Zone Management Act. In addition, we provide support to local governments on critical areas ordinances (CAOs) under the state Growth Management Act and for shoreline master programs under the Shoreline Management Act.

For information on the role of other state agencies involved in wetland management, see Appendix A of the Washington State Wetland Program Plan.

Local governments

In general, the state emphasizes a local approach to wetland protection and regulation. The Growth Management Act (GMA) authorizes and requires cities and counties to regulate wetlands within their jurisdictions. Under GMA, local governments are responsible for designating and protecting wetlands by adopting critical areas ordinances (CAO) and are encouraged to augment regulatory protection with incentives for voluntary conservation. We serve an advisory role by providing comments during CAO updates and by offering technical assistance.

Local governments develop comprehensive land-use plans that ensure future growth meets the needs of the community while protecting natural resources and the environment. These plans often include provisions for wetlands and aquatic resources. Shorelines and their associated wetlands are protected through locally administered shoreline master programs under the Shoreline Management Act.

Federal agencies

U.S. Army Corps of Engineers

The Corps plays a central role in wetland regulation at a federal level. The Corps administers Section 404 of the Clean Water Act (CWA) and Section 10 of the Rivers and Harbors Act. The Corps, jointly with the EPA, determines the jurisdiction for waters of the United States, including wetlands, for all discharges of dredged or fill material associated with activities occurring in the nation’s waters.

U.S. Environmental Protection Agency

The EPA co-administers the Section 404 of the Clean Water Act with the Corps. Under Section 404 of the CWA, the U.S. Congress directed the Corps to develop a permit program and regulations to administer it. Congress also directed EPA to develop the substantive environmental criteria, which the Corps must demonstrate are met to issue permits.The EPA also writes CWA Section 401 water quality certifications on tribal lands where the tribal governments do not yet have the authority to administer Section 401.

Our federal regulations webpage outlines recent changes to federal rules that are affecting projects and wetlands within our state.

Tribal governments

There are 29 federally recognized Indian tribes in Washington State whose governments manage natural resources on reservations and nearby federal trust lands. Wetlands within reservations or on tribal lands may be managed by tribal governments in cooperation with the EPA, Corps, the Bureau of Indian Affairs, and various landowners. On reservations and on tribal trust lands, both tribal and federal regulations may apply.

Within reservations and other lands reserved or held in trust by the United States for federally recognized Indian tribes, tribal governments may have adopted regulations to protect wetlands and other waters. These regulations vary with each tribe, depending upon tribal resources and the ownership characteristics of their reservation.