State wetland regulations

We regulate wetlands in Washington state regardless of federal jurisdiction. Wetlands are protected and managed through multiple state laws, including the state Water Pollution Control Act and the Shoreline Management Act. The State Environmental Policy Act (SEPA) process identifies potential wetland-related concerns early in the environmental review and permitting process. Additionally, we have authority to review and approve projects under Section 401 of the federal Clean Water Act.

We also provide technical assistance to local governments under the Growth Management Act. This includes assistance in developing comprehensive plan policies and development regulations and in implementing local wetland regulations.

Will your project have potential impacts to wetlands?

Applicants and consultants should coordinate with our regional wetland staff on projects that have potential impacts to wetlands. When a proposed project has potential impacts to wetlands, applicants should work with the appropriate city or county and U.S Army Corps of Engineers (Corps) to determine if the wetlands are regulated under local or federal laws. Based on the Corps' determination, activities in wetlands in Washington may be authorized by Ecology through one of the following processes:

  • Section 401 Water Quality certifications: For federally regulated wetlands, applicants must submit a request for a Section 401 Water Quality certification under the federal Clean Water Act. Section 401 of the federal law provides the state authority to approve, approve with conditions, or deny proposed projects directly affecting waters of the United States, including wetlands, to ensure they meet state water quality standards. When an individual Section 401 Water Quality certification is needed, any actions necessary to protect water quality are included as conditions in the certification and incorporated into the federal permit.
  • State Administrative Orders (Non-Federally Regulated Wetlands): For non-federally regulated wetlands, applicants must submit a request for an administrative order to comply with the state Water Pollution Control Act (Chapter 90.48 RCW). We issue administrative orders under this act for impacts to wetlands that aren't jurisdictional under the federal regulations (e.g., non-federally regulated wetlands, or NFRs). These wetlands remain protected under state and local laws and rules.

See the "Applicant resources" tab below for information on how to request regulatory approval. 

For projects that propose to impact wetlands, applicants must seek regulatory approval. Applicants seeking a federal permit or a state authorization for a non-federally regulated wetland should submit requests for regulatory approval to our Federal Permit Unit by email to

Resources and links

State laws that protect wetlands are broader than current federal regulations. The state can establish protocols for managing wetlands falling outside federal jurisdiction. For example, impacts to wetlands outside federal jurisdiction are authorized through administrative orders under the state Water Pollution Control Act.

In general, the state emphasizes a local approach to wetland protection and regulation. The state Growth Management Act (GMA) authorizes and requires cities and counties to regulate wetlands within their jurisdictions. This is typically accomplished by adopting a Critical Areas Ordinance (CAO). We play an advisory role by providing comments during CAO updates and offering technical assistance.