What are the floodplain requirements for my residential/commercial structure?
In areas where flood elevations are known, the lowest floor including basement must be a least one (1) foot above the base flood elevation. Base flood elevation, also known as the BFE or 100-year flood, is the term used for a flood having a one (1) percent chance of being equaled or exceeded in any given year and the elevation at which it may occur.

If flood elevations are not known in the area you are developing, a site inspection by the Spokane County Floodplain Management staff is required. If it is not clear that the proposed home will be outside of the floodplain, the applicant is asked if they could relocate to a safer (clearly out of the floodplain) area upon the property. The applicant may also hire an engineer to more precisely delineate the floodplain and establish a BFE for the property. Construction of the lowest floor including basement must be one (1) foot above the newly established BFE. Residential homes must elevate above the BFE and commercial structures have the option to flood proof above the BFE.

Show All Answers

1. What is a floodplain?
2. What is floodplain management?
3. What is a 100-year flood?
4. Who determines where these floodplains are located?
5. Why does Spokane County have floodplain regulations?
6. Is development allowed in a floodplain?
7. When is a Floodplain Development Permit required?
8. What is considered development?
9. What are the Floodplain Requirements “A” Zones?
10. What are the floodplain requirements for my residential/commercial structure?
11. What are the floodplain requirements for dock projects?
12. What are the floodplain requirements for fill, grading, excavation and crossing structures?
13. What is a "B" zone?
14. What if my property is associated with a “B” Zone floodplain?
15. What is a "C" zone?
16. What if my property is associated with a “C” Zone floodplain?
17. What are the requirements for additions or improvements to structures?
18. What are the requirements for floodproofing?
19. What are the fees for development permits?
20. What is an Elevation Certificate?
21. Why is an Elevation Certificate required?
22. When is an Elevation Certificate required?
23. Why is an Elevation Certification bond taken?
24. Who can fill out an Elevation Certificate?