Grays Harbor County, WA Environmental Rules: Flood Zones (2026)
FEMA flood zone rules in Grays Harbor County, WA, also called floodplain regulations or special flood hazard area (SFHA) rules, determine flood insurance requirements and elevation standards for new construction.
Key Facts
- Permit required
- any construction/fill in mapped flood hazard area
- Governing maps
- Flood Insurance Study dated 9-18-2020, FIRM
- Elevation standard
- lowest floor 1 ft above BFE (AE/A1-30)
- Floodway new residential construction
- prohibited, limited repair exception
- Variance authority
- Board of Adjustment, meant to be rare
- Office of record
- Planning and Building, Montesano
Summary
In unincorporated Grays Harbor County, no one may build, fill, or place a manufactured home within a mapped special flood hazard area without a floodplain development permit under Grays Harbor County Code Section 18.06.480. Planning and Building administers the rule against FEMA's Flood Insurance Study and Flood Insurance Rate Maps, and new floors generally must sit at least one foot above the base flood elevation.
A permit shall be obtained before construction or development begins within any area of special flood hazard established in Chapter 18.06. Such permit is required for all structures, including manufactured homes and for all development including fill and other activities, as set forth in this title. ... The applicant shall be responsible for the costs of providing the required information, including the costs associated with determining and setting elevations at the development site where required by this chapter.
Full Breakdown
Before any construction, fill, or manufactured-home placement begins within a special flood hazard area of unincorporated Grays Harbor County, the applicant must obtain a floodplain development permit under Grays Harbor County Code Section 18.06.480, part of the county's frequently-flooded-areas article of Chapter 18.06. The county maintains the governing Flood Insurance Study for Grays Harbor County, dated September 18, 2020, along with the accompanying Flood Insurance Rate Maps (FIRM), on file at the Planning and Building Division, 100 West Broadway, 3rd Floor, Montesano, per Section 18.06.460.
Permit applications must state the elevation of the lowest floor relative to mean sea level, disclose any flood-proofing, and identify federal or state clearances needed under Section 404 of the Clean Water Act and the state Shorelines Management Act. Under Section 18.06.500, new residential construction in AE and A1-30 zones must have the lowest floor elevated at least one foot above the base flood elevation, and manufactured homes must be anchored to a permanent, elevated foundation. Section 18.06.510 goes further inside a mapped floodway: new residential construction is prohibited outright except for repairs or improvements that do not enlarge the footprint and cost less than half the structure's market value, with a narrow carve-out for replacement farmhouses on long-term agricultural land.
Property owners who cannot meet these standards may ask the Board of Adjustment for a variance under Section 18.06.530, but the code warns variances 'should be quite rare' and are limited to small, already-built-up lots. The administrator, not a self-certifying applicant, decides whether a site sits in the floodway, and every variance and its written findings must be logged under Section 18.06.540 and reported to the Federal Insurance Administration. The chapter's disclaimer at Section 18.06.470 makes clear the county accepts no liability for flood damage even where a permit has been properly issued.
Violations & Fines
Building or filling in a special flood hazard area without the Section 18.06.480 permit, or below the elevation required by Section 18.06.500, is enforced through the county's Chapter 8.40 code enforcement process administered by Planning and Building, which can order a stop-work action and require retrofitting or removal before a certificate of occupancy issues. Non-residential structures flood-proofed instead of elevated must carry a professional engineer's certification on file before occupancy is allowed, and unpermitted floodway encroachments face the same abatement path as any other code violation.
Frequently Asked Questions
Do I need a permit to fill my yard if it's in a flood zone in unincorporated Grays Harbor County?
Can I rebuild a house that's inside a designated floodway?
Where does the county keep the flood maps that decide whether my property needs a permit?
Sources & Official References
Other rules in Grays Harbor County
Compare Grays Harbor County to another location·View the Washington environmental rules overview
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