Island County, WA Right to Farm: Agricultural Zoning Protection (2026)
Key Facts
- CA minimum lot size
- 20 acres
- RA minimum lot size
- 10 acres
- CA base density
- 1 dwelling per 20 gross acres
- RA base density
- 1 dwelling per 10 gross acres
- Max building height
- 35 feet, with narrow exemptions
- EDU allocation rate
- 0.20 EDU per easement acre
- Enforcing agency
- Planning and Community Development
Summary
Unincorporated Island County zones farmland into Rural Agriculture (RA) and Commercial Agriculture (CA) districts specifically to protect working farms from interference by non-farm neighbors. RA requires a 10-acre minimum parcel and caps base density at one dwelling per 10 gross acres; CA requires 20 acres with at least 25 percent prime soils and caps density at one dwelling per 20 gross acres.
The primary purpose of the Commercial Agriculture (CA) Zone is to protect and encourage the long term commercially productive use of Island County's agricultural resource lands of long term commercial significance that have been designated pursuant to RCW 36.70A.170. It is established to identify geographic areas where a combination of soil, and topography allow commercial farming practices to be conducted in an efficient and effective manner; to help maximize the productivity of the lands so classified; to protect farming operations from interference by non-farmers; and to maintain agricultural land areas for agriculture use free from conflicting non-farm uses. ... B.Lot/density.1.Minimum lot size shall be twenty (20) acres. Base density shall be one (1) dwelling unit per twenty (20) acres of gross site area.
Full Breakdown
" To carry the CA designation, a parcel (or contiguous parcels under one owner) must total at least 20 acres, have at least 25 percent prime soils, and have been enrolled in the open-space agricultural tax program as of June 2, 1999. 090 uses the same protective language on a 10-acre minimum with one unit per 10 acres. Both zones cap building height at 35 feet, exempting silos, chimneys, flagpoles and similar structures. 19. Nonresidential development unrelated to farming is capped at less than 2 acres per 20 acres of the farm unit.
Farm produce stands and seasonal farmers markets are permitted outright in RA, CA and Rural Forest zones. Planning and Community Development administers zoning review; the Hearing Examiner or Board handles PRDs and management plans.
Violations & Fines
Subdividing or building below the 10-acre RA or 20-acre CA minimums without an approved boundary line adjustment, short plat or EDU allocation is a zoning violation Planning and Community Development can deny at permit review. Nonresidential (non-farm) construction exceeding the 2-acres-per-20-acres cap on RA, RF or CA land is likewise a violation, as is exceeding base density without an approved PRD or recorded conservation easement. Unpermitted structures over these limits can be denied approval or ordered removed.
Frequently Asked Questions
What is the minimum lot size for Commercial Agriculture zoning in Island County?
Does Island County's zoning code protect farmers from nuisance complaints?
How does an Earned Development Unit work on Commercial Agriculture land?
Can I build a second house on Rural Agriculture land?
Sources & Official References
Other rules in Island County
Compare Island County to another location·View the Washington right to farm overview
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