As much needed rain falls across Los Angeles and Ventura Counties and gives firefighters relief from ongoing wildfires, officials are warning residents of hazardous waste, toxic ash runoff and mudslides.
The National Weather Service has issued a flood watch beginning at 4:00 p.m. PDT on Sunday through 4:00 p.m. PDT Monday that includes areas scorched by the fires known as "burn scars."
Any thunderstorm that forms could bring "brief heavy downpours and gusty winds may occur," the NWS said.
Los Angeles and Ventura Counties are forecast to receive 0.75 to one inches of rain, with 1.5 to three inches of rain expected for the mountains. San Luis Obispo and Santa Barbara Counties are expected to receive up to one inch of rain in the mountains with a slight chance for 1.5 to three inches, according to the NWS. There is also a chance of small hail, and waterspouts over waters off the California coast.
"High rain over a burn scar may result in debris flows or mudslides. Follow the instructions of local officials!," the NWS Los Angeles office .
Fast-moving mud, debris and rocks "can pose serious dangers to roads and homes," the California Department of Forestry and Fire Protection , adding that residents should "stay prepared and alert!." The department cautions those in areas impacted by the fires to be ready to evacuate to higher ground and have an emergency plan. Driving through areas with debris and flooding should also be avoided.
Officials across multiple agencies, including the , have begun cleaning up debris to "safely dispose of hazardous materials from all burned areas." This also includes ash from burned vegetation, buildings and cars that cover areas scorched by the fire and spread to other areas by the winds.
Los Angeles Mayor Karen Bass also signed an emergency executive order early last week directing city crews to "install reinforced concrete barriers, lay down sandbags and clear debris to shore up burn areas and stem the flow of toxins."
"With rain in the forecast, it's imperative we take aggressive action to prevent additional damage in burn areas and to protect our water and ocean from hazardous runoff," Bass .
Firefighters have made progress on the fires, with the Palisade Fire 87% contained, the Eaton Fire 95% contained and the Hughes Fire, which broke out on Wednesday morning, 92% contained, .
Hazards from wildfire damage
Damage from wildfires pose several safety and health hazards, including from hazardous materials and chemicals, according to the.
Fire debris and ash contain "harmful substances" such as asbestos, heavy metals and toxic chemicals, Los Angeles County Department of Public Health Director Dr. Barbara Ferrer said during a press conference last week.
"Heavy metals such as lead and arsenic can come from burned electronics and building materials and even a brief exposure can potentially cause skin irritations and lead to more serious illness," she continued.
Residents in burned areas who have been cleared by local authorities to return home should take "precautions to protect your health and safety," .
An N95 mask is recommended on returning to homes, which protects users from breathing in harmful particles, as well as safety goggles which protect the eyes from ash, debris and smoke. Long-sleeved shirts, long pants and gloves are recommended to protect the skin. Residents also should not remove hazardous debris without assistance.
Officials also advise those in wildfire areas to monitor the air quality going forward, and wear an N95 mask whenever there is smoke, dust and ash in the air.
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