Douglas County, CO Environmental Rules: Defensible Space (2026)

Douglas County Zoning Resolution § 1-1702 defines defensible space as a natural or man-made area where vegetation capable of carrying fire has been treated, modified, or removed to slow a fire's spread, reduce its intensity, protect firefighters, and stop fire from traveling between a structure and the surrounding vegetation. That definition is operative, not decorative: § 1-1707(1) lets the county require a fuel modification and vegetation management plan wherever a hazard assessment under § 1-1705 flags the parcel, and the plan must be prepared by a professional forester holding a bachelor's degree accredited by the Society of American Foresters plus two years of Rocky Mountain regional experience.

The plan must identify fuel type, condition and loading together with slope and aspect, and must reduce fuel loading and modify fuel types around structures and adjacent vegetation, including cutting fuel breaks and fire breaks under § 1-1707(1)(A)-(C). The precise clearance distances and vegetation specifications sit in the separately adopted Douglas County Wildfire Mitigation Standards (Exhibit B of the county's International Building Code), which § 1-1701(3)(C) and § 1-1707 incorporate by reference; the zoning resolution itself sets the trigger and planning process rather than one universal clearance distance, because required treatment varies with each site's slope, aspect and existing vegetation.