Cal Fire pulled out its big guns Tuesday after four spot fires at the same time were reported near the Caldecott Tunnel. They had seven aircraft, 11 fire engines and two bull dozers on the fire line within a half hour.
Flames raced up the hill on the Contra Costa County side of the tunnel just as the evening commute got under way.
The fires were ignited along state Highway 24 at Fish Ranch Road near Orinda, a Contra Costa County Fire Protection District dispatcher said.
The fire was reported at 3:04 p.m. and within an hour burned about 20 acres. The flames were pushed up the hill by very windy conditions in the area.
There was lots of smoke in the area, but helicopter video showed traffic appeared to be moving.
Crews appeared to have the fire knocked down by 5 p.m. They said they would remain on the scene for at least 24 hours looking for hot spots.
Cal Fire says it was able to keep the fire to 30 acres. No homes or structures were ever threatened.