Boulder staff present draft wildfire‑resilient landscaping rules; requirements to apply mainly to redevelopment

Boulder city staff presented a working draft of wildfire‑resilient landscaping guidelines to the Environmental Advisory Board, proposing new requirements for properties inside an expanded wildland‑urban interface and recommending voluntary measures for existing homes.

The draft, introduced by Brett Kincaren, senior division manager for the nature‑based solutions team in the city’s Climate Initiatives Department, lays out three scales of action — community‑scale WUI zones, parcel‑level “home ignition zones,” and emergency response improvements — and matches a pared list of 2025 priorities to those scales. Kincaren said the recommendations “are based on the best available, both science and experience that we have.”

Why it matters: staff said the proposed changes would affect a far larger area than the original WUI boundary and would apply as code requirements only to properties inside the designated WUI when those properties undergo new development or redevelopment. A board member noted the change in scale: “It affects 16,000 homes.” That expansion, staff said, follows modeling of how embers travel in high winds and the Marshall Fire experience, which showed structure loss often began with ember ignition rather than structure‑to‑structure spread.

Key proposals and technical points

- WUI expansion and ember modeling: Staff described modeling used to map an expanded WUI footprint based on ember‑cast distances under high‑wind conditions. The draft proposes three WUI subareas that guide where different…