A damage inspection process of 22 structures due to the fire was completed Sunday, revealing the destruction of two single-family residences and two utility structures, according to CAL FIRE.
The three structures that received minor damage included two single-family residences and one miscellaneous structure.
As of 4 p.m. Sunday, firefighters were holding the blaze at 152 acres with 50% containment, fire officials said.
The wildfire is burning north of Timber Cove in Sonoma County near the coast.
Crews have been strengthening and holding containment lines while three specialized tree-felling teams remove fire-damaged and hazardous trees that could threaten firefighters and create safety hazards during suppression efforts.
The fire was first reported around 1:45 p.m. Thursday in the 24000 block of Highway 1 in Timber Cove.
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Firefighters make steady progress
Crews planned to focus on strengthening and holding containment lines as onshore winds of 10 to 15 mph were expected to increase along the coast Sunday afternoon and evening, CAL FIRE said.
Fire officials also requested three specialized tree-felling teams to remove fire-damaged and hazardous trees that could threaten firefighters and create safety hazards during suppression efforts.
The wildfire's size remained unchanged Sunday as firefighters continued working to increase containment.
Dramatic video released by the California Highway Patrol shows firefighters facing intense conditions Thursday night as flames burned on both sides of Highway 1.
At nearby Gerstle Cove Campground, host Tom King said he quickly began evacuating campers as the fire moved closer.
"I started evacuating, immediate evacuation of everything, because it looked like it was going to take over the campground," King said.
The campground was full of summer visitors at the time. Campers left in a hurry, abandoning RVs, tents and other belongings as they fled.
More than 300 firefighters have been assigned to the incident, battling flames in dense coastal forests and rugged terrain.
CAL FIRE Battalion Chief Michael Sacheli said cooler overnight temperatures helped crews gain the upper hand.
"Things are looking a lot better. Crews made good progress," Sacheli said.
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Still, firefighters faced significant challenges from dry vegetation, dead trees and spot fires.
"Fuel moistures and dry trees contributed to lots of spot fires. That's where the challenges were," Sacheli said. "We're trying to get ahead of the fire and protect structures."
Firefighting aircraft made multiple retardant drops around threatened areas. Several homes were coated in pink retardant but escaped damage.
King said the situation was intense as aircraft worked overhead.
"The smoke was right there. They started bombing quick. I about got hit with the pink stuff. It was real close," he said.
Evacuation orders and warnings have been lifted, and firefighters continue working to strengthen containment lines and keep the fire away from homes and critical infrastructure.
Bay City News contributed to this story.