L.A. firefighters oversee drainage of a pool in the yard of a Hollywood Hills home. The pool was compromised as soil shifted during the recent rains.(Gary Coronado / Los Angeles Times)
Sunlight breaks through storm clouds in Manhattan Beach.(Luis Sinco / Los Angeles Times)
Firefighters inspect a home being built on Stanley Avenue in the Hollywood Hills. Amid the rain, soil shifted, and several workers and some nearby residents were evacuated.(Gary Coronado / Los Angeles Times)
Jeff Crawford, left, a supervisor with the Riverside County Transportation Department, surveys debris flowing from Horsethief Canyon, a Holy fire burn area, on Jan. 17. The debris flowed over a section of Temescal Canyon Road, which was closed.(Allen J. Schaben / Los Angeles Times)
Workers with the city of Malibu clear debris from Clover Heights Avenue near the intersection of Harvester Road on Jan. 16.(Katie Falkenberg / Los Angeles Times)
Heavy machinery is used Jan. 17 to remove debris flowing from Horsethief Canyon in Riverside County.(Allen J. Schaben / Los Angeles Times)
With barricades positioned in the street to direct the flow of potential mudslides, a Riverside County sheriff’s deputy keeps watch amid rain in the McVicker Park area of Lake Elsinore.(Allen J. Schaben / Los Angeles Times)
Elmer Cruz of North Hills uses his umbrella to add an extra layer of protection from the rain while watching an Australian Open tennis match on his mobile device at a Lake Balboa park.(Mel Melcon / Los Angeles Times)
The January storm meant umbrellas on Hollywood Boulevard.(Wally Skalij / Los Angeles Times)
A pedestrian is framed by a mural on Washington Boulevard in Culver City.(Genaro Molina / Los Angeles Times)
Pedestrians make their way through Old Town Pasadena as a week of wet weather continues.(Allen J. Schaben / Los Angeles Times)
L.A. Department of Building and Safety workers examine a mudslide that damaged a house and a guest house on Boris Drive in Encino.(Genaro Molina / Los Angeles Times)
Will Reid, from Torrance Beach, rides a wave at Zuma Beach in Malibu.(Katie Falkenberg / Los Angeles Times)
Will Reid, from Torrance Beach, walks out of the water with a broken board after surfing at Zuma Beach in Malibu.(Katie Falkenberg / Los Angeles Times)
Sean Tabibian takes cellphone photos of a mudslide across the street from his home on Martson Drive in Encino. The mudslide damaged a house and guest house down below along Boris Drive.(Genaro Molina / Los Angeles Times)
Sheriff’s Deputies Ryan Singer, left, and Miguel Herrera walk through Paradise Cove mobile home park in Malibu alerting residents of mandatory evacuations in the Woolsey fire burn areas.(Katie Falkenberg / Los Angeles Times)
Daniel Lazar, a resident of the Paradise Cove community in Malibu, signs a form for Deputies Ryan Singer, right, and Miguel Herrera, acknowledging that he was disobeying evacuation orders at his own risk.(Katie Falkenberg / Los Angeles Times)
Deputies Ryan Singer, right, and Miguel Herrera go door to door in Paradise Cove alerting residents of mandatory evacuations.(Katie Falkenberg / Los Angeles Times)
Sheriff’s Deputy Miguel Herrera knocks on a door in Paradise Cove in Malibu to alert residents of mandatory evacuations.(Katie Falkenberg / Los Angeles Times)
A crew works to clear a small mudslide on Pacific Coast Highway near Leo Carrillo Beach in Malibu.(Katie Falkenberg / Los Angeles Times)
Pedestrians hoist umbrellas against the rain on Wilshire Boulevard in Los Angeles.(Allen J. Schaben / Los Angeles Times)
A woman huddles under an umbrella as she walks in the rain in Los Angeles.(Allen J. Schaben / Los Angeles Times)
The latest in a series of winter storms that have hammered Southern California for days sent soil sliding from beneath a house in the Hollywood Hills, forcing evacuations, and a boulder tumbling down a hillside in Malibu, leaving a hiker critically injured.
The 57-year-old woman was pummeled by the large boulder Thursday on Rambla Pacifico Street, the Los Angeles County Sheriff’s Department said.
No one was injured in the Hollywood Hills slide, but fire officials evacuated five workers from the home, which is under construction above Stanley Avenue, along with residents of about 20 surrounding homes, for several hours.
Four of those homes were yellow-tagged; authorities told those residents they could go home but must stay out of their backyards. Geologists will assess the area for potential danger, Los Angeles Fire Department spokesman Brian Humphrey said.
In Echo Park, a fourplex was red-tagged — meaning no one can go inside — when its staircase collapsed, causing soil and debris to slam into two parked cars, he said.
By 8:30 p.m., the Fire Department was on its “1,800th incident today,” Humphrey said. “Every single one has some nexus to the rain.… It’s been a very busy day.”
Bands of heavy precipitation that moved into L.A. early Thursday from an “atmospheric river” — a long plume of water vapor pouring over from the Pacific Ocean and swollen with subtropical moisture — also wreaked havoc on roadways, causing dozens of crashes, including an overturned car that blocked several lanes on the southbound 110 Freeway in Highland Park.
A flooded tunnel closed a portion of the northbound 101 Freeway near the East Los Angeles interchange downtown shortly after 5 a.m., and a stretch of Topanga Canyon Road was cordoned off after boulders and mud slid from the hillside onto the roadway. A massive boulder that fell into the roadway briefly closed Stunt Road in Calabasas between Mulholland Highway and Schueren Road.
Female hiker, 57, is in critical condition after being pummeled by a large boulder that tumbled down to Rambla Pacifico Street this morning. Please avoid canyon areas that are prone to loose boulders, flash floods & debris flow. #Malibu #LARain pic.twitter.com/9lEXgG1TY8— LASD Lost Hills Stn. (@LHSLASD) January 17, 2019
In Ventura County, about 50 people were evacuated from an RV resort near the 101 Freeway just before floodwaters from the Ventura River inundated the property. Muddy water that pooled in the resort’s parking lot rose to the top of the doors of two trucks and an SUV that had been left behind.
The National Weather Service warned that periods of heavy rain could trigger shallow mud and debris flows in areas recently devastated by wildfires.
The soil in burn areas cannot absorb a lot of moisture, so heavy rainfall can lead to fast-moving flows containing mud, debris and even trees and boulders. When rain falls over time, it can be gradually absorbed or dispersed, but when areas see rapid runoff, entire hillsides can come down without warning, sometimes with deadly results.
Riverside County officials issued mandatory evacuations for several communities near the Holy fire burn area. They were lifted and made voluntary at about 6 p.m. Thursday. Debris flows and flooding in the area closed a portion of Temescal Canyon Road shortly after 11:30 a.m.
Previous flood alerts in Ventura and Los Angeles counties expired as rainfall lessened in those areas, and residents of 300 homes in the Woolsey fire burn area were allowed to return home. Malibu schools were closed for a third consecutive day because of the rain but were scheduled to reopen Friday.
The storm, which moved into the region Wednesday, was expected to dump from 1½ to 3 inches of rain along the coast in Ventura and Los Angeles counties through Thursday evening. The foothills could see up to 5 inches of precipitation by the time the rain tapered off, forecasters said.
Much of Southern California had already received a heavy soaking. By 10 a.m., about 1.79 inches of rain had fallen on downtown Los Angeles in a 24-hour period, while Nordhoff Ridge in Ventura County had been hammered with 6.88 inches — the most in the region. A storm cell that hovered over Seal Beach late Wednesday dropped more than 3 inches and caused roads and a beach parking lot to flood. A stretch of Pacific Coast Highway in Huntington Beach also remained closed after the road flooded on Wednesday.
Heavy rain also forced the closure of Knott’s Berry Farm and Six Flags Magic Mountain. Disneyland and Universal Studios remained open.
The series of storms also knocked out power for thousands of people throughout the state. Pacific Gas and Electric said about 68,000 customers in Northern California remained in the dark Thursday, down from 220,000 the previous day. Southern California Edison reported about 2,000 customers without power.
Thursday’s precipitation was the final punch in nearly a week of wet weather across the state, and the rains could signal movement in the right direction for California’s lackluster water supply, said retired climatologist Bill Patzert.
“The big picture is that really for the last two decades, we’ve mostly been in a rain-deficit situation, so the result of course is that groundwater basins all over California are extremely low,” he said. “Coming into this winter we are rain-needy.”
Meteorologists said the storm brought blizzard conditions to the higher elevations of the Sierra Nevada with several feet of fresh snow and winds surpassing 50 mph. Heavy overnight snowfall upended a Citation X Cessna airplane at Truckee Tahoe Airport, leaving the nose pointed upward for several hours.
The state’s rainy season — which lasts through March — consists of about 10 storms, on average, Patzert said. This series of unusual back-to-back events has put California ahead of schedule in terms of rain, which could signal positive steps to replenishing the state’s depleted reservoirs, he said.
“It took us years to get into this water deficit, and it will take us years to get out,” he said. “This is several days of sweet rainfall, but it’s no solution. It’s a good start.”
The Associated Press contributed to this report.