How LA neighborhoods near burn scars are preparing for storm – NBC Los Angeles

Public works crews in Los Angeles County have been clearing debris basins and storm drains, and handing out sandbags to residents ahead of the most intense periods of rain from a powerful mid-February storm.

As part of those preparations before the brunt of the storm on Thursday, LA County has been working with federal agencies to develop a system for containing debris that may start flowing from within the Palisades and Eaton fire burn zones. The goal is to contain any flows in the street and prevent streams of mud, water, rocks, tree branches and other debris from reaching property.

During Wednesday’s county news conference, Los Angeles County Public Works Director Mark Pestrella said rainfall rates that exceed a half-inch per hour can lead to mud and debris flows, depending on topography, the soil system, geology and the status of the flood control system. He said crews have been working around the clock to ensure the county’s 154 debris basins are clear and are ready to capture mud and debris that could crash down mountain slopes.

“We are in a state of readiness with those facilities,” Pestrella said. “We have the capacity for the size of storm that we expect to come with this storm.”

A system of thousands of miles of K-rail and hundreds of thousands of sandbags will be used to help capture debris before it reaches streets, Pestrella said. If it does, the flows will be diverted and contained on streets to prevent it from reaching waterways, which would lead to the ocean in the Palisades area, he said.

“This is unusual,” he said. “We don’t typically want any debris to end up in the streets.”

The rain is moving in, and it will be enough to make roads slippery today, but the heaviest rain is still expected for Thursday. The rainfall rate will be high and cause big concerns for mud and debris flows. 

In Altadena, bright green compost filter socks, mesh tubes filled with composted material, were placed around properties to contain hazardous materials. Barriers also were placed around storm drains to prevent hazardous waste from flowing into the stormwater system. K-rails were positioned in the street, adding another layer of flooding and debris flow protection.

Pestrella urged residents who think they may be at risk to contact the county at 800-675-4357 to have their property evaluated. The service is available at any county location, not just the recent fire areas.

“This service is going to be provided right up to and to the point that we can no longer get to your properties,” he said.

Rain will ramp up Thursday afternoon as the system moves from west to east through the evening and overnight. That period will bring the highest risk of flooding problems and debris flows in wildfire burn scar areas.

LA County officials are asking residents to prepare for the incoming atmospheric storm surge seriously, and that evacuations are possible. Michelle Valles reports for NBCLA at 11:00 a.m. on Feb. 12, 2025

“Recent burn areas from the Palisades (Pacific Palisades), Hurst (Sylmar), Kenneth (West Hills), and Sunset (Hollywood Hills) fires are at a higher risk of debris flows and water runoff that may contain hazardous substances,” the city of Los Angeles said in a statement. “Additional safety messages may be directed at these neighborhoods… Get ready and take extra precautions, especially if you are in an area that was impacted by the recent wildfires.”

A flash flood watch goes into effect for much of the region at 1 p.m. Thursday through 4 a.m. Friday. A flash flood watch indicates conditions that could lead to flash flooding. A flash flood warning, which could be issued during the storm, indicates flooding is happening or imminent.

The rain will turn to showers on Friday, decreasing that afternoon.