“Flood of Rocks and Mud” Block 91 Freeway in Anaheim Hills

Large rocks and mud blocked the eastbound lanes on the 91 Freeway after a hillside collapsed early Wednesday in Orange County and trapped vehicles in the debris.

California Highway Patrol reported a “flood of rocks and mud coming down” the hillsides during heavy overnight rains as a storm system moved through the region.

All eastbound lanes were shut down overnight west of Green River Road in the Anaheim Hills area. At least two lanes are expected to remain closed into the afternoon. Transition lanes from the northbound Eastern Transportation Corridor (241) to the eastbound 91 Freeway also were closed.

Vehicles caught in the debris were finally extricated almost two hours after the initial slide, according to the CHP incident log.

Aerial video showed a significant eastbound traffic backup early Wednesday as CHP officers directed drivers off the freeway near Gypsum Canyon Road. At the site of the slide, crews with heavy construction equipment attempted to remove a thick layer of mud that spanned all lanes.

A geologist was expected to visit the site to determine whether the hillside has stabilized. Protective concrete barriers will be placed at the site of the collapse to prevent more debris from flowing onto the road.

No injuries were reported.