Evacuation Warnings Issued in Altadena and Pasadena as Major Storm Bears Down on Southland

With a potentially dangerous storm bearing down on the Southland, evacuation warnings will take effect in multiple areas Thursday amid fears that steady downpours could spark flooding, mudslides and debris flows.

Much of the northern portions of Altadena and the Kinneloa area of Pasadena are under Evacuation Warnings which were to take effect at 7 a.m. this morning and remain in force until 2 p.m. on Friday.

Pasadena police and Altadena Sheriff’s deputies went door to door Wednesday evening in affected areas issuing evacuation warnings.

Fire officials said specific homes considered to be at high risk will be subject to mandatory evacuation orders.

Pasadena Public Information Officer Lisa Derderian said 10 homes in Pasadena were issued mandatory evacuation orders.

The brunt of the storm — which began with generally light rainfall across the region Wednesday — is expected to hit the Los Angeles area around mid-afternoon Thursday, about three to six hours earlier than previous predictions.

A flash flood watch was issued by the National Weather Service for the bulk of Los Angeles County for Thursday morning through Thursday evening, with forecasters saying flooding and debris flows are possible, with the greatest risk in or near the Eaton, Palisades/Franklin and Bridge fire burn scars.

L.A. County public works crews have been working for days to prepare for the storm — emptying debris basins, clearing storm drains and distributing sandbags to residents. In the Eaton Fire burn zone, the county Department of Public Works and the sheriff’s department have also been warning residents living in homes that may be at high risk of damage from mudslides or flooding, and advising them to prepare to evacuate.

“Please, if evacuation orders are made, … keep your safety in mind,” Luna said. “They help to protect you and your loved ones from potential danger. Storms can bring sudden and severe conditions that make staying back home extremely risky. … Please take necessary steps now to prepare. Pack an emergency kit, secure important documents and ensure that you have a plan in place for your pets and family members.

“And remember, if you’re ordered to leave, you may be gone for several days. I cannot stand up here and tell you will be gone for 12 hours, 24 hours. We don’t know. It depends on the weather and the post-weather events that will impact your specific neighborhood.”

Luna said deputies have also been canvassing flood-prone areas such as the Los Angeles River to warn homeless people who may be camped there to relocate.

“Unfortunately, we witnessed numerous, numerous instances in the past of swift-water rescues where people were caught in dangerous, fast moving water, and obviously, we want to prevent that,” he said.

The NWS has described the multi-day storm system as likely to be “the biggest precipitation producer so far this season.”

Only about a quarter-inch of rain was expected to fall on Wednesday, but by the time the brunt of the storm exits the area on Friday, roughly 1 to 3 inches of rain are expected in most coastal and valley areas, with 3 to 6 inches anticipated in the foothills and mountains.

“The cold front will be capable of producing rainfall rates (that) meet or exceed the thresholds for debris flow in the burn scars … and flood watches have already been posted for those areas,” according to the National Weather Service. “However, minor flooding of roads is likely just about anywhere.”

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, although factors such as topography, the soil system, geology and the status of the flood control system all contribute to the potential for such occurrences. He insisted, however, that crews have been working around the clock to ensure the county’s 154 debris are clear and have the capacity to capture mud and debris that could descend 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.”

He noted that the 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, hoping to contain any such flows on streets in those areas.

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

But he said using a vast system that includes thousands of miles of K- rail and hundreds of thousands of sandbags, crews are hoping to capture debris before it reaches streets, but 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.

Pestrella said that while the county has been working to notify residents in the fire zones whose homes may be at increased danger of experiencing mudslides, he 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.

The Los Angeles County Department of Public Works was distributing free sandbags at the La Costa Post Office, 21229 Pacific Coast Highway in Malibu, for people in the Palisades Fire area. For those in the Eaton Fire area, the county was offering sandbags at Robinson Park, 1081 N. Fair Oaks Ave., and Victory Park, 2575 Paloma St., both in Pasadena.

A full list of locations where sandbags are available is at lacounty.pw/sandbags.