Multnomah County, OR Environmental Rules: Defensible Space (2026)
Key Facts
- Minimum fuel break
- 50 feet around buildings
- Applies in
- CRGNSA forest zones only
- Steep-slope setback
- 50 ft from 30%+ grades
- Compliance review
- within 1 year of occupancy
- Enforced by
- Planning Director
Summary
Inside the Columbia River Gorge National Scenic Area's forest zones, new buildings must be surrounded by a maintained 50-foot defensible space fuel break clearing hazardous fuels to cut wildfire risk under Multnomah County's own Gorge overlay code.
All buildings and structural projections such as porches, balconies and decks shall be surrounded by a maintained defensible space fuel break of at least 50 feet to minimize the risks associated with wildfire, unless the County approves an alternative pursuant to (B)(2) or (B)(3) below. Hazardous fuels shall be removed within the defensible space fuel break area.
Full Breakdown
Multnomah County Code § 38.7305(B), part of the Gorge overlay's Fire Protection in Forest Zones standards, requires all buildings and projections like porches, balconies and decks to be surrounded by a maintained defensible space fuel break of at least 50 feet. Hazardous fuels must be removed from that area; irrigated or fire-resistant vegetation, green lawn and low shrubs under 24 inches are allowed. Trees need over 15 feet between crowns, pruned of dead and low branches, with accumulated leaves and needles cleared beneath them. The fuel break must extend farther on steeper slopes, though the County or local fire district can approve a different distance. This section applies only within the Scenic Area's forest-designated zones, not countywide.
Violations & Fines
The Planning Director reviews new dwellings for compliance within one year of occupancy under § 38.7305(F). Buildings lacking the required 50-foot fuel break or built without an approved alternative are out of compliance and subject to county code enforcement.
Frequently Asked Questions
Does this rule apply to my Portland home?
How far must the defensible space extend?
What vegetation is allowed within the fuel break?
Sources & Official References
Other rules in Multnomah County
Compare Multnomah County to another location·View the Oregon environmental rules overview
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