SAN DIEGO COUNTY MARKS FIFTH YEAR USING PHOS-CHEK GROUND-APPLIED FIRE RETARDANT ALONG HIGH FIRE-RISK ROADWAYS

San Diego County Fire working to treat all high fire-risk County roads

San Diego, CA 26 August 2025 – The County of San Diego is working with Clayton, MO-based Perimeter Solutions, a leading global manufacturer of high-quality fire retardant and firefighting foam, to apply PHOS-CHEK® long-term fire retardant as part of the County’s efforts to proactively protect high fire-risk County roads from wildfire.

“My constituents have consistently said that fire safety and prevention is a top priority. This innovative and proactive approach we have taken helps keep everyone in our county safer,” said Supervisor Joel Anderson, representing District 2 on the San Diego County Board Supervisors.

The County of San Diego maintains nearly 2,000 miles of roadway, many of which serve as key corridors for area evacuation and response to wildfires. More than 200 miles of roadways have been deemed high-fire risk, including Wildcat Canyon, an area historically prone to wildfire activity. Wildcat Canyon experiences heavy vehicular traffic daily, and with its steep terrain, cars and trucks are more likely to overheat, emitting sparks that could—and have—ignite wildfires. It also serves as a crucial evacuation corridor for Eastern San Diego County.

County Fire will treat high fire-risk roadways with PHOS-CHEK throughout the season, including vulnerable and traditionally underserved communities.

Ground-based PHOS-CHEK is based on the same technology as the red fire retardant used by CAL FIRE for aerial application. It is dropped from aircraft during active wildfires to prevent their spread and to give firefighters on the ground additional time to contain and extinguish the fire. The ground-based version is an uncolored, highly durable fire retardant that is applied on flammable vegetation and cellulosic material one time early in the fire season before a wildfire approaches to provide ongoing protection from wildfire that remains effective until a significant rain event occurs.

“We are proud to continue our partnership with the County of San Diego in their efforts to protect lives and property from wildfires. Their proactive strategy serves as a model for other communities facing similar wildfire risks. By leveraging advanced fire retardant technologies like PHOS-CHEK, San Diego County is leading the way in wildfire prevention and demonstrating a commitment to the safety and well-being of its residents,” says Shannon Horn, Chief Operating Officer at Perimeter Solutions.

San Diego County’s wildfire mitigation strategy is partially supported by a Community Wildfire Defense Grant (CWDG). The CWDG Program was authorized as part of the Bipartisan Infrastructure Law, which put aside $1 billion dollars over five years to cover the costs for areas at high-risk for wildfire to mitigate those risks. Local community and tribal leaders working to reduce the risk of wildfire are encouraged to apply to receive CWDG grants, and to incorporate PHOS-CHEK into their wildfire mitigation strategies.