The Whittier Fire began on July 7 when a hot vehicle ignited a tall patch of dry grass at Camp Whittier, located off Highway 154 near Lake Cachuma. The fire grew rapidly because of high temperatures and an abundance of fuel. The area had not burned in several decades.
Staff at the nearby Rancho Alegre were forced to evacuate without notice. Several of its structures were burned, and much of its livestock died. At the same time, around several dozen people, mostly children, were forced to shelter in place at Circle V Ranch Camp as the fire burned around them. The fire grew to 7,800 acres and mandatory evacuations were issued for Highway 154 and West Camino Cielo west of the Winchester Gun Club. The fire grew steadily over the next few days to 13,000 acres as limited vehicle access and a lack of natural barriers complicated containment efforts.
Despite difficult terrain, moderate winds and high humidity allowed firefighters to reach 52% containment by the end of the week. An unexpected wind event on the night of Friday the 13th caused the fire to expand in several directions. By the following morning the fire had grown to 17,000 acres and containment fell to 35%.
By July 16, 2,200 firefighters were assigned to the area and over 2,700 people were under evacuation. Over the next several days, aggressive aerial assaults and use of the Sherpa Fire burn scar allowed firefighters to slow the fire’s growth and gradually increase containment. Containment did reach 100% until October 5, and infrared scans still showed lingering hotspots for months to come. The Sherpa Fire burned 18,291 acres, destroying 16 structures.
Roughly 18 months later, on the morning of February 2, 2019, a strong downpour across the burn scar of the Whittier Fire trigger a debris flow in Duval Canyon. The event clogged and damaged a culvert beneath Highway 154, shutting down all lanes in both directions for a month.