The California Highway Patrol’s Clear Lake Area office said the wreck occurred at 6:40 p.m. on Highway 29 south of Spruce Grove Road.
The CHP said Gabrielle Dorsett, 57, of Santa Rosa, was arrested for suspicion of driving under the influence of alcohol.
Also involved in the wreck were Patsy Thorburn, 80, driving a 2011 GMC, and her passenger, Henry Everett, 78, both of Clearlake; and Alexis Stafford, 36, of Kelseyville, driving a 2005 Dodge, the CHP said.
The report explained that Dorsett was driving her 1986 Mercedes southbound on Highway 29 near Spruce Grove Road, while Thorburn was driving her GMC northbound with Everett in the front passenger seat. Stafford was driving her Dodge northbound behind Thorburn.
As the vehicles approached each other, the CHP said Dorsett allowed her vehicle to leave the southbound lane and drift into the northbound lane, directly into Thorburn’s path, with the two vehicles colliding head-on.
The CHP said Stafford observed the collision and swerved to the right to avoid it, causing her Dodge to leave the roadway and hit a metal fence.
All drivers remained on scene until the CHP arrived, the report said.
The CHP said Dorsett was arrested for DUI and was transported to Adventist Health Clear Lake for treatment of major injuries.
Thorburn and Everett, both of whom had moderate injuries, also were transported to Adventist Health Clear Lake for treatment, while Stafford was uninjured, according to the CHP.
All four individuals were wearing using their safety equipment, the CHP said.
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