KERRY MANN navigates the large boulders and mudflow that destroyed the home of her friend in Montecito. The woman who lives in the home has not been seen since the early hours of Tuesday. At least 15 people died and thousands fled their homes in Southern California as a powerful rainstorm triggered flash floods and mudslides on slopes where a series of intense wildfires had burned off protective vegetation last month.
Rivers of mud wreak havoc in California
01:14 - Source: CNN
CNN  — 

Searchers in California sifted through mud-caked debris Monday for three people missing in mudslides that have killed at least 20 and walloped Montecito, the Santa Barbara County Sheriff’s Office said.

The Santa Barbara County Sheriff’s Office announced Sunday that 30-year-old Pinit Sutthithepa had been found dead on Saturday. Four people remain missing.

Sutthithepa’s 2-year-old daughter, Lydia, is among the missing, the sheriff’s office said. Sutthithepa’s 6-year-old son, Peerawat, and his 79-year-old father-in-law, Richard Loring Taylor, were both found dead on January 9.

The mudslides came in the early morning hours of last Tuesday, destroying an estimated 65 homes and damaging hundreds of others, the California Department of Fire and Forestry Protection said.

Rescue crews continue to sift through mud and wreckage looking for the missing, said Cal Fire, adding, “The large amounts of mud and debris are making access and progress challenging.”

Santa Barbara County Sheriff Bill Brown announced Saturday that search and rescue crews had found the body of 25-year-old Morgan Corey, whose 12-year-old sister, Sawyer, was found dead earlier in the week.

Those killed ranged in age from 3 to 89, and all lived in Montecito in Santa Barbara County, northwest of Los Angeles, authorities said.

In addition to Lydia Sutthithepa, John “Jack” Cantin, 17; Faviola Benitez Calderon, 28; and John “Jack” Keating, 53 are missing.

Sunday night the sheriff’s office said the search-and-rescue operation is now a search-and-recovery effort.

For days, rescuers searched frantically for the missing after mud and boulders barreled into neighborhoods in and near Montecito, an affluent seaside community east of Santa Barbara. The mudslides demolished homes and left roads impassable.

“In disaster circumstances, there have been many miraculous stories of people lasting many days. We certainly are searching for a miracle right now,” Brown said Thursday.

“But realistically we suspect that we are going to continue to have discovery of people who were killed in this incident.”

How to help the victims of the California mudslides

US 101, a major freeway connecting Northern and Southern California, remains closed. It’s not clear when the highway – which officials had said would reopen on Monday – will be cleared for travel.

The exact timing of the freeway’s reopening is unknown, California Highway Patrol Captain Cindy Pontes said Friday.

‘I just want to find my friend’

The immediate areas where people were killed are under mandatory evacuation, and officials increased the size of the evacuation zone Thursday.

“We know that this a terribly inconvenient development, but it is also incredibly necessary,” Brown said.

He said the zone, which includes areas formerly under voluntary evacuation advisories, would be in effect for one week but that residents should plan for two.

Rescue workers are using helicopters and all-terrain vehicles in a search hampered by blocked roads and downed trees and power lines.

There’s also the issue of removing massive boulders that have been strewn throughout the area.

Todd Ferryman, superintendent of Access Limited Construction, and his men have been drilling holes into boulders. Crews will drop a nontoxic, biodegradable “expansion agent” that will break down the boulders into more manageable sizes.

Crews working to break down boulders on January 14, 2018, in Montecito, California.

“It’s kind of like putting water in a rock and freezing it,” Ferryman said. “It expands up and it cracks the rock.”

Ferryman and his crew will be working seven days a week until the area has been cleared, he said. “There’s a lot of people out here that haven’t been able to get to their homes yet and see them,” he said. “So the sooner we get this open and safe for the public, the sooner we can get everybody back to their lives.”

On the morning of the storm he woke up to the sound of thunder and went downstairs. About 30 minutes later, he was watching 2 to 3 feet of water streaming down the street when he looked over to the sight of the neighbor’s car blasting through a stone wall that surrounded the property.

Geologist: Risk of mudflow remains for years

The storm hit hard between 3 and 6 a.m. Tuesday. The rain poured down on hillsides charred by recent wildfires, which burned vegetation that otherwise could make the terrain more resistant to mudslides.

The Thomas Fire – the largest wildfire in California’s recorded history – has burned more than 281,000 acres in Santa Barbara and Ventura counties since it began in early December. It’s still burning.

Google Earth/Wally Skalij/Los Angeles Times/Getty Images

Geologists and forecasters warned that intense rain could trigger deadly mudslides from the scorched areas.

And because of the fire, communities below the scarred terrain could remain at risk of mudflow for a few years, said Randall Jibson, a research geologist with the US Geological Survey.

Montecito may be at slightly less risk now, because this week’s flooding already brought down vulnerable material.

“(But) no storm brings down everything that is susceptible. There’s almost always more” that could come down, he said.

What can be done? Long term, one option would be more basins to slow down storm runoff and collect debris.

Short term, making the public ready to evacuate during heavy rains is key, he said.

Montecito and Carpinteria are especially vulnerable to mudslides because the steep terrain in some places goes from thousands of feet above sea level to sea level in “a matter of just a few miles,” said Tom Fayram, a deputy public works director with Santa Barbara County.

CNN’s Paul Vercammen, Lindsay Benson, Jason Hanna, Joe Sutton, Dave Alsup, Stella Chan and Sonya Hamasaki contributed to this report.