Floodplain Development Regulations Update - What & Why
What’s Happening Now?
SDCI completed the SEPA process for the proposed permanent Floodplain Development Regulations and has transmitted the legislation to City Council for their review and approval.
SDCI has also submitted legislation to extend the interim regulations for 6 months. City Council held a public hearing on the legislation on December 17, 2025. SDCI posted a notice for this proposal in the November 17 issue of the Land Use and Information Bulletin under Other Land Use Notices.
City Council passed the extension of the interim regulations on January 13, 2026, and Mayor Wilson signed the legislation on January 20,2026.
Project Benefits
Our floodplain development regulations protect people, property, and the environment by regulating the development that occurs in the mapped floodplain and flood prone areas. The new permanent regulations will adopt FEMA’s 2020 new Flood Insurance Rate Maps and Flood Insurance Study and will continue to regulate flood prone areas mapped by Seattle Public Utilities. Below are examples of development regulations and these regulations vary depending on the specific flood zone designations, characteristics of the property, and the nature of the development.
- The elevation that the first floor of a new structure must be built at to keep the first story above anticipated flood levels
- Structures must be engineered to withstand wind from anticipated storms
- Structures must be engineered to withstand flood waters should anticipated flood levels be exceeded
The End Result
The permanent Floodplain Development Regulations will meet FEMA's 2020 requirements.