All eastbound lanes of Highway 4 near Rodeo were shut down for nearly 2 hours Sunday afternoon as fire crews battled a brush fire and downed power lines, the California Highway Patrol said.
A Sig-alert was issued just before 5 p.m., and CHP was diverting traffic from the freeway at Franklin Canyon Road as Contra Costa Fire District crews battled the blaze.
Lanes were reopened about 6:30 p.m., the CHP said.
PG&E also was on the scene to clear the downed power lines, the CHP said.
The fire had burned about 35 acres on both sides of the freeway and was 55 percent contained as of Sunday evening, according to fire officials.
The cause of the fire was not known. There were no injuries reported or structures damaged.