Environment & Science

6 things homeowners should know about post-wildfire mudslides

A home damaged by mudslides on Nov. 1, 2014 was buried after an overnight storm caused mudslides in Camarillo Springs on Dec. 12, 2014.
A home damaged by mudslides on Nov. 1, 2014 was buried after an overnight storm caused mudslides in Camarillo Springs on Dec. 12, 2014.
Maya Sugarman/KPCC
A home damaged by mudslides on Nov. 1, 2014 was buried after an overnight storm caused mudslides in Camarillo Springs on Dec. 12, 2014.
Shadow Hills resident David Schneider (left) learns how to protect his home from debris flows from L.A. County Department of Public Works civil engineer Mike Miranda (right foreground) and his assistant Danny Su.
Emily Guerin/KPCC


Listen to story

01:00
Download this story 0.0MB

The La Tuna Fire left more than 300 homes in Burbank and LA at risk of mudslides. So all month, engineers from the Los Angeles County Department of Public Works have been going door to door teaching people how to protect themselves.

KPCC tagged along as department staff visited residents in Shadow Hills. Here’s what we learned.

The risk of mudflows is highest the first three years after a fire

Burned soils aren’t very good at absorbing water, meaning more rainfall will run off instead of seeping into the ground. Without plants to hold soil in place, the water can easily carry away topsoil, ash and even boulders. Once plants start growing back, the risk of mudflows subsides. 

YouTube

Houses at the bottom of steep, burned slopes are most at risk

The farther away your house is from the bottom of a hillside, the safer it is. That way the debris has a chance to settle out and slow down before it hits your home.

The age of your house can make a difference

Newer houses often have retaining walls or other barriers separating them from hillsides to protect them from mudflows. But according to civil engineer Mike Miranda with L.A. County Public Works, older homes frequently do not have this kind of protection.

Sandbags line a home at the base of a hill in Camarillo Springs, Ventura County, in Dec. 2014.
Sandbags line a home at the base of a hill in Camarillo Springs, Ventura County, in Dec. 2014.
Maya Sugarman/KPCC

There are things you can do to direct mudflows away from your house

Low walls made of wood and reinforced with railroad ties can channel debris around homes or away from sensitive outdoor equipment, like central air conditioning units. And sandbags and plastic sheeting can keep debris from entering sliding glass patio doors. (Check out this cool gif)!

You might have to evacuate

Some properties are always going to be at high risk of being severely damaged by mudflows. For those residents, L.A. County engineers recommend that in the case of a forecast of heavy rains, board up your windows and evacuate.

LA County Department of Public Works civil engineer Mike Miranda checks out a debris basin that was damaged by the La Tuna Fire with Shadow Hills resident David Schneider. Debris basins protect foothill neighborhoods from dangerous mudflows.
LA County Department of Public Works civil engineer Mike Miranda checks out a debris basin that was damaged by the La Tuna Fire with Shadow Hills resident David Schneider. Debris basins protect foothill neighborhoods from dangerous mudflows.
Emily Guerin/KPCC

Monitor that debris basin in your neighborhood

Many foothill neighborhoods have debris basins, which look like small gravel pits, at the bottom of canyons to catch mudflows and help water absorb into the ground. But depending on who maintains the basins, they may not be emptied out all that regularly, meaning they won’t be able to absorb as much water or debris in the next storm. Find out which agency is responsible and give them a call if your basin is looking full or has a lot of trees or brush growing in it.