Wetland regulation & permitting resources

We protect and manage wetlands through multiple state laws, which define our regulatory authority. Two state laws, the state Water Pollution Control Act and the Shoreline Management Act, give us the authority to regulate wetlands. We also use the State Environmental Policy Act (SEPA) process to identify potential wetland-related concerns early in the permitting process.

In addition, we 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 impact a wetland?

Our regional wetlands staff review applications for projects that have the potential to impact wetlands and other "waters of the state." Applicants who propose altering aquatic resources must go through mitigation sequencing to avoid and minimize impacts before determining whether compensatory mitigation is appropriate and a permit is required.

We regulate wetlands regardless of federal jurisdiction

Applicants and consultants should coordinate with our staff on projects that will have potential impacts to wetlands. When a proposed project will have potential impacts to wetlands, applicants should also work with the U.S Army Corps of Engineers to determine if the wetlands are regulated under federal law. This determination will affect the permit pathway as follows: 

  • If a wetland is determined to be jurisdictional by the Corps, we review the proposal affecting the jurisdictional wetland under Section 401 of the Clean Water Act (Section 401 water quality certifications). 
  • If a wetland is determined to not be jurisdictional by the Corps, we review the proposal affecting the non-jurisdictional wetland under the state Water Pollution Control Act, Chapter 90.48 RCW (Administrative Orders).

Section 401 water quality certifications

Section 401 of the federal Clean Water Act provides the state authority to approve, condition, or deny proposed projects in "waters of the U.S.," 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 401 certification and incorporated into the federal permit.

State Administrative Orders (Non-Federally Regulated Wetlands)

We issue Administrative Orders under the state Water Pollution Control Act, Chapter 90.48 RCW, for impacts to wetlands that are not jurisdictional under the federal regulations (i.e., non-federally regulated wetlands or NFRs). These wetlands remain protected under state and local laws and rules. 

Permitting resources

Regulation of specific wetland types Local wetland regulations