Floodplain Development Regulations Update - What & Why

Floodplain Development Regulations

What’s Happening Now?

SDCI will be extending the interim floodplain development regulations a seventh time in August 2024 for an additional 6 months.The proposed permanent floodplain regulations were appealed in July 2021 by the Port of Seattle. Since then, we have been working with the port to resolve issues related to the appeal. Additionally, we withdrew our July 2021 SEPA Decision, and we will be publishing a new SEPA decision in 2024.

In preparation for publishing the new SEPA decision we have posted the staff draft of the regulations for public review. These draft regulations are now posted on the Project Documents page. Additionally, the adopted interim floodplain development regulations are also included on the Project Documents page.

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 2019 new Flood Insurance Rate Maps and Flood Insurance Study and will continue to regulate flood prone areas mapped by Seattle Public Utilities. Development regulations vary depending on the specific flood zone designations, characteristics of the property, and the nature of the development including first floor elevation. Below is a list of development regulations:

  1. The elevation that the first floor of a new structure must be built at to keep the first story above anticipated flood levels
  2. Structures must be engineered to withstand wind from anticipated storms
  3. 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.

Construction and Inspections

Nathan Torgelson, Director
Address: 700 5th Ave, Suite 2000, Seattle, WA, 98104
Mailing Address: P.O. Box 34019, Seattle, WA, 98124-4019
Phone: (206) 684-8600
Phone Alt: Violation Complaint Line: (206) 615-0808
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SDCI issues land use, construction, and trade permits, conducts construction and housing-related inspections, ensures compliance with our codes, and regulates rental rules. SDCI is committed to an antiracist workplace and to addressing racism through our work in the community.