Walla Walla County, WA Fire Regulations: Brush Clearance (2026)

Section 15.04.520(C) and (D) of the Walla Walla County Code, adopted by Ordinance No. 384 in 2010 as part of the Mill Creek Wildfire Protection Area standards, set the county's vegetation-management requirement for new construction inside the mapped wildfire zone defined by the 2006 Mill Creek Community Wildfire Protection Plan and County Resolution 06-069. Every new structure that requires a building permit inside that boundary must be surrounded by a fire break of not less than thirty feet, measured from the structure itself, and no portion of a tree or other vegetation may come within fifteen feet of the outlet of a chimney, heat-producing vent or stovepipe anywhere on the property.

The two clearances serve different purposes: the thirty-foot fire break is meant to stop ground and brush fire from reaching the structure, while the fifteen-foot vegetation setback from vent outlets keeps limbs and foliage away from sparks and embers exiting a flue. The Community Development Department's building official reviews both distances at permit application and can waive or reduce only the thirty-foot fire break, and only on a specific finding that the full clearance is impractical on that lot; the code gives the official no comparable authority to waive the fifteen-foot chimney setback.

Because these are permit-stage building standards rather than a nuisance-abatement rule, they apply once, at construction, rather than as an ongoing brush-removal mandate enforced after the fact.