Rain hinders search for remains but helps contain Northern California wildfire

Hundreds of volunteers will spend the American Thanksgiving holiday combing through ruins in heavy rain, looking for the remains of victims killed in the deadliest wildfire in California history, with strong winds and the risk of mudslides an additional complication.

The fire killed at least 83 people, but 563 people remain unaccounted for in and around Paradise, a community of nearly 27,000 people that was largely incinerated by the so-called Camp Fire two weeks ago, Butte County Sheriff Kory Honea said.

Searchers moving through affected areas around Paradise, about 300 kilometres northeast of San Francisco, are expected to face heavy rains that may hinder their efforts. Forecasters say as much as 150 millimetres of rain could fall through the weekend.

Warehouses were opened in nearby Chico to provide evacuees protection from the cold and rain as celebrity chef Jose Andres prepared to cook hundreds of Thanksgiving meals for evacuees.

Rivers of mud

The rains, which in some areas were likely to be accompanied by winds of up to 70 km/h raised risks of ravines turning into rivers of mud. The fire has burned across 620 sq. kilometres of the Sierra foothills but is now 90 per cent contained.

"There's no vegetation to hold the earth and there's a risk it could just start moving, with mud carrying everything in its path," National Weather Service forecaster Johnnie Powell said in Sacramento.

The death toll has been gradually rising, with two more names added to the list on Wednesday to bring the total to 83 people, with 58 of them tentatively identified, Honea said.

The number of people unaccounted for, which has fluctuated widely over the past week, declined by 307 to 563 on Wednesday.

Asked about the effects of rain on the search for remains, Honea said it would make going through debris more difficult but he was less concerned about remains washing away than the headaches posed by mud.

Still, he said some remains might never be found.

"What we're looking for in many respects are very small bone fragments so, as we go forward, it's certainly possible that not all of them will be located," Honea said.

The Camp Fire incinerated 13,503 homes in and around Paradise. The cause of the fire remains under investigation.

The state is undertaking the largest single wildfire cleanup operation in its history to remove toxic and radioactive ash and debris at burned home sites, said Eric Lamoureux from the Governor's Office of Emergency Services.

Butte County says evidence from recent fires in California showed that some destroyed homes and property contained "high and concerning levels of heavy metals, lead, mercury, dioxin, arsenic and other carcinogens. Some property may have the presence of radioactive materials."

In Southern California, fire officials announced the Woolsey, which burned from Thousand Oaks to Malibu, west of Los Angeles, is fully contained. Rain is also expected in the region today, meaning risk there, too, of mudslides and rockslides. 

Three people were killed in the fire and 1,600 homes were destroyed.