State Environmental Policy Act (SEPA) Code
See also: Land Use / Master Use Permit - State Environmental Policy Act (SEPA), Environmentally Critical Areas (ECA) Code
What Is It?
Our State Environmental Policy Act (SEPA) ordinance requires that we assess the environmental impacts of projects that meet certain criteria. The SEPA section of our Seattle Municipal Code (SMC) is based on the provisions of the State Environmental Policy Act in the Washington Administrative Code (WAC).
If SEPA is required for your project, we will do the review as part of the land use permit process.
Read the Code
- Tip 208, When Environmental Review Is Required in Seattle
- Environmental (SEPA) Checklist
- Director's Rule 9-2023, Exemptions from State Environmental Policy Act (SEPA) Requirements
- Director's Rule 13-2021, Determination of State Environmental Policy Act (SEPA) Review Exemption Levels for Infill Residential and Mixed-Use Development in Urban Centers and Urban Villages
- Director's Rule 9-2018, Determining if two or more development proposals are considered as one for applying State Environmental Policy Act categorical exemptions and Design Review thresholds
- Director's Rule 11-2017, Installation of Large Signs for Public Notice
- Director's Rule 2-98, Clarification of State Environmental Policy Act (SEPA) Historic Preservation Policy for Potential Archeologically Significant Sites and Requirements for Archeological Assessments
- Director's Rule 41-96, Selection of Environmental Impact Statement (EIS) Consultants
- Director's Rule 49-88, SEPA Exemption on Split-Zoned Lots
Recent Changes
SEPA Changes to Promote Housing Effective July 23, 2023
Seattle has made considerable progress in planning for housing growth in both its comprehensive plan and land use codes. In recognition of that progress, the Washington State Legislature has amended the State Environmental Policy Act (SEPA) to help reach those goals by expediting the review of development that includes housing. As of July 23, 2023, most projects proposing additional housing units are exempt from SEPA review, including several types of residential and mixed-use developments that would have previously undergone SEPA review. This SEPA change does not affect other SDCI discretionary approvals, such as Design Review, that may be required for specific proposals. This SEPA amendment will be in effect until September 30, 2025.
Here are responses to some frequently asked questions.
On January 20, 2023, the state proposed SEPA related amendments removed parking as an element of the environment and revised the environmental checklist. As a result of new state law, SDCI will no longer identify and analyze parking impacts in its SEPA analysis. A new Environmental (SEPA) checklist is available on the SDCI forms page and required with submittal of a Master Use Permit for project proposals that require SEPA.