Flooding hits California areas scarred by wildfires

Flash flooding hit a wildfire-scarred area of Northern California on Thursday, while the southern part of the state was hit with mudslides and heavy rains.

Northern, southern parts of state impacted

Parts of Northern California that were recently devastated by the Camp Fire were hit with flash flooding on Thursday. (Rich Pedroncelli/Associated Press)

Flash flooding hit a wildfire-scarred area of Northern California on Thursday, forcing officials to deploy swift-water rescue teams to save people stuck in vehicles and rescue them from homes after a downpour near the Paradise area.

Authorities said they used boats to rescue people from three homes and told people in about 100 vehicles to stay in place until the rain receded in late afternoon. They received reports of flooding on roads and of downed trees and utility poles.

Thursday's storm brought nearly four centimetres of rain in an hour, toppling trees and trapping motorists in flooded roads downstream, said National Weather Service meteorologist Craig Shoemaker.

"This is heavy rain in a short period of time, and that's the worst thing that can happen in the burn scar," he said.

The Butte County Sheriff's Department ordered evacuations but could not say how many people were affected. The water rescues were in an area of Chico, which is downhill from Paradise and a city where many of the wildfire evacuees have been staying since the town of 27,000 was destroyed just three weeks ago by a deadly wildfire.

At least 88 killed in wildfire

Paradise has been under mandatory evacuation orders for nearly three weeks since a wildfire killed at least 88 people and destroyed nearly 14,000 homes.

Residents could begin returning early next week, but only if the storm doesn't hinder efforts to clear roads and restore power, Butte County Sheriff Kory Honea said.

Honea said he was optimistic that some who remain unaccounted for will turn up alive, but he also left open the possibility that "bones or bone fragments" of additional victims could turn up as evacuation zones are reopened to civilians.

The search for more human remains in the Paradise area officially ended Thursday, with at least 88 people confirmed dead and nearly 200 still listed as missing. (John Locher, File/Associated Press)

The cause of the Camp Fire, which was fully contained earlier this week, remained under investigation. But power utility PG&E Corp. reported equipment problems near the origin of the fire around the time it began on Nov. 8.

The official roster of people unaccounted for has fluctuated widely from day to day, but as of Wednesday night the list was winnowed to 196 names, down from a peak of 1,200-plus over a week ago.

The sheriff said the list had since been scrubbed of all duplicate names and that investigators had caught up with a backlog of unprocessed missing-persons reports.

People evacuated — again

Dale Word, a firmware engineer, was evacuated briefly Thursday from his semi-rural Chico neighborhood for the second time this month.

Word waded out in thigh-high water to higher ground until the rain receded, leaving a mess of sticky mud and debris. He said he was stunned by the disasters that have hit Butte County. The fire came within several hundred feet of his home.

"Everywhere you go you're talking to people who have lost everything and it's just tragic," Word said, jokingly adding, "It feels like the four horsemen of the apocalypse are going to come riding over the hill any day now."

People from three homes in Word's Chico neighborhood were rescued by boat, said Rick Carhart, a spokesperson with the California Department of Forestry and Fire Protection. Honea said that at one point, people in about 100 vehicles were told to stay in place.

Emergency response crews earlier cleared a tree that toppled in the town of Magalia, but no other reports of damage had been received after more than 2.5 centimetres of rain fell overnight in the burn zone about 225 kilometres northeast of San Francisco.

Southern California also impacted

In Southern California, authorities ordered evacuations in a small Malibu community within a wildfire burn zone where a mudslide blocked roads amid heavy rains.

Los Angeles County Sheriff's Deputy Joana Warren said residents of several homes were told to leave as streets filled with mud, ash and debris during a downpour. She said no injuries were reported.

A mudslide trapped several vehicles along along a road in San Bernardino County, Calif. (Stan Lim/Orange County Register via Associated Press)

In the zone that burned this month, the city of Malibu warned of rocks falling on canyon roads, and Pepperdine University closed its campus.

The storm knocked out power and flooded roadways across greater Los Angeles. Numerous traffic accidents occurred on slick freeways, and most vehicles travelling in the mountains were ordered to put chains on their tires. Mud and rock slides also closed two mountain highways.

Residents were urged to voluntarily evacuate a string of neighbourhoods about 70 kilometres southeast of Los Angeles along a flank of the Santa Ana Mountains where a fire burned thousands of acres last summer. Mandatory evacuations were ordered for a small section of the city of Lake Elsinore beneath a burn zone.

West of Los Angeles, rain fell heavily at times in vast areas burned by fires this month and last December — an area where there are strong memories of a January downpour that unleashed devastating debris flows through the community of Montecito that killed 21 people and left two missing.

On the coast near Big Sur, the California Department of Transportation closed a 19-kilometre stretch of Highway 1 because of potential instability.

The scenic route perched between towering mountainsides and the ocean has been dogged by slides since 2016. But the one that hit in May 2017 was monumental, requiring extensive work to rebuild the highway.

The weather service also issued a backcountry avalanche warning for most of the central Sierra, including the Lake Tahoe area.

With files from Reuters