Rainy season likely to bring debris flow and mudslides in burned Santa Cruz Mountains

SANTA CRUZ MOUNTAINS, Calif. (KION) The CZU August Lightning Complex is just days from reaching full containment. However, the nearly 87,000 acres that burned could easily lead to mudslides when rain strikes next.

County officials say in some areas there's an 80-100 percent chance of a mudslide with a rain storm.

“You can get landslides with as little as a quarter inch of rain. In fact, we’ve had crews up there inspecting some of the areas and the dirt is already starting to move,” County of Santa Cruz spokesman Jason Hoppin said.

Due to the steep drainage and mountain terrain, Cal Fire officials said you can't stop or temper the possibility of landslides.

The most concerning natural disaster is debris flow, according to Cal Fire CZU Chief Ian Larkin. Debris flow happens when enough rain causes the Earth to shift in a water way. If its strong enough, the debris flow will wipe out anything in its path.

“It's dangerous for the public," Larkin said. "You can’t outrun them, and you can’t get out of the way of them.”

The County of Santa Cruz is putting together plans to stop debris flow and erosion, but there's not much that can prevent it. K-Rail can be used and other barriers, but timely evacuations are the best way to save lives.

“Early notification and getting people out of the way. Evacuating those areas, because mother nature and those things are going to occur and there’s not a whole lot we can do to stop it," Larkin said.

Steep mountain terrain that’s vegetation has now been stripped away and turned to ash means mudslides will happen this winter. The county says it's most likely west of Empire Grade.

“You have a lot of homes that have been positioned on hillsides for the view," Hoppin said. "There’s a real risk to a lot of [homes] that have survived the fire going forward.”

Scientists are still trying to determine how much rain it could take for a debris flow to happen in Santa Cruz county and that will give officials a better idea of when or if any evacuations would be necessary when it rains.