The incident was reported at 10:30 a.m., when a commercial dump truck veered out of the northbound lanes and struck a power pole near Idylwild Drive, CHP Officer John Darling said.
The California Highway Patrol responded and closed the No. 2 lane in the northbound direction, Darling said.
PG&E teams are still at the scene replacing the damaged pole. Until that happens, crews cannot move the dump truck and reopen the other lane, Darling said.
Darling said he recommends that drivers take a detour on Idylwild Drive to bypass the part of the highway affected by the accident.
He said around 1:45 p.m. that he expected it would be at least two or three hours before the site is cleared.