City departments outline wildfire prevention steps; fire marshal recommends targeted, site‑specific assessments

The Land Use and Transportation Committee held a hearing on Nov. 4 to review wildfire prevention and management practices on lands owned or operated by city departments and partner entities, focusing on Mount Sutro, the Presidio, Glen Canyon, McLaren Park, reservoir lands and other open spaces.

Supervisor Norman Yee opened the hearing by noting changes in regional fire behavior and asking agencies to explain what the city is doing to prevent wildfires on undeveloped and underdeveloped public lands.

UCSF’s Mark Freiberg described the Mount Sutro Open Space Reserve (about 60 acres, over 10,000 trees and roughly 5.5 miles of trails) and its 20‑year vegetation management plan. UCSF said it uses no herbicides in the reserve, has initiated goat grazing to remove blackberry (2018: ~8 acres; 2019: >4 acres), trims ladder fuels and creates buffer zones between the reserve and adjacent structures.

The Presidio Trust reviewed its wildfire hazard assessment and said the overall fire risk in the Presidio is low due to long‑running vegetation management, but it is implementing additional defensible‑space and thinning measures. Rec and Park described annual spring abatement to create roughly 30 feet of defensible space where parkland abuts residences, tree hazard assessments executed by third‑party arborists, and resource constraints around labor and maintenance. SFPUC said it conducts fuel reduction on reservoir lands, creates fuel breaks of 30–100 feet where appropriate and coordinates with neighbors to clarify property responsibilities. The Port said most of its waterfront parcels are irrigated or paved and act as useful fire breaks.

Fire Marshal Dan DeCascio reviewed the applicable code baseline: California and local fire code require removal of combustible (dead/dry) vegetation and generally call for a 30‑foot defensible space around structures. He explained that state fire hazard maps (Cal Fire) classify hazard zones and that San Francisco is primarily a local responsibility area classified as moderate; as a result, the most stringent wildland‑interface chapter (Chapter 49) does not automatically apply unless the city opts in or designates areas as very‑high hazard. DeCascio recommended the committee consider site‑by‑site assessments and interagency task forces to identify specific mitigation steps where local conditions (slope, canopy continuity, fuels) warrant greater measures. He said the Fire Department currently responds to complaints and partners with agencies but is open to proactive inspections.

Public comment urged more proactive, non‑complaint‑driven assessments for places like Mount Davidson, Glen Canyon and McLaren Park; speakers also advocated expanding native plant nurseries, installing auxiliary water supply systems in high‑risk neighborhoods and considering aerial firefighting capacity for extreme events. The committee filed the item for follow up and directed departments to consider targeted assessments, coordination and potential resource needs for proactive mitigation work.

Key takeaways

- Agencies perform routine fuel reduction: trimming ladder fuels; removing dead wood; mowing and clearing in spring; targeted goat grazing and defensible‑space work near structures. - The Fire Marshal identified 30 feet as the current baseline defensible‑space standard but said local authorities can require larger defensible space or site‑specific spacing depending on topography and vegetation. - Supervisors asked for interagency coordination and a targeted, resource‑backed assessment plan to identify high‑priority sites for proactive mitigation and to return with concrete proposals.