The community of La Conchita — the site of previous devastating landslides — is under warnings from Ventura County officials that current weather patterns "may lead to conditions consistent with the occurrence of past geological events."
This story includes reporting by Nate Perez, Jackie Fortiér, Michael Flores and former LAist reporter Carla Javier.
What's going on? Rain, rain and more rain.
As of Wednesday, current rainfall totals for La Conchita — which the county has deemed a geologic hazard — over the last two weeks are nearing 4.5 inches. Ventura County officials said the devastating 2005 landslide occurred after about 8 inches of rain fell over 14 days.
A few hundred people live in the coastal community, which is unincorporated and offers relatively affordable oceanside living.
Eighteen years ago this week, a massive landslide buried homes in La Conchita, killing 10 people. Some 400,000 tons of earth tumbled down the hillside in an event witnessed by many on live television. Ten years before that deadly event, another big landslide damaged or destroyed 14 homes.
Those events have been studied extensively, underpinning a letter sent Jan. 7 to La Conchita residents and signed by the Ventura County sheriff and fire chief. It says in part:
Due to the complex nature of the hazards present in the Community of La Conchita, public safety personnel have no way to predict if or when a failure of the hillside may occur. Because of this, residents should not wait for local authorities to issue evacuation warnings or orders before leaving the area. It is advisable that residents monitor weather forecasts, rainfall rates and current conditions of the hillside to determine when they need to evacuate. This information may be found at: LaConchitainfo.com or by visiting VCEmergency.com
Among the possible outcomes "known about ancient landslides and the 1995 and 2005 landslides" listed:
Jeremy Lancaster, a landslide geologist with the California Geological Survey, says the risk will only be reduced when the ground dries.
"So that threat can diminished, but with another successive rainstorm, the threat is reestablished," Lancaster said.
That's concerning given new storms forecast for the coming days. And in areas not affected by recent fires, like La Conchita, landslide threats can last days to weeks after after a significant rainfall that is butted against another strong storm.
Lancaster said the 2005 La Conchita landslide was a deep, slow-moving landslide in a non-burn area.
"So the threat of these big, deep landslides occurring after a heavy rain year like we're seeing now may continue into the summer," he said.
Since Monday, more than a foot of rain has fallen in the mountains above Montecito, Summerland, and Carpinteria, which led to evacuation orders earlier this week.
While the atmospheric river responsible for recent heavy rains triggered mud and debris flows, Christina Favuzzi, a spokesperson for the Montecito Fire Dept., said infrastructure improvements after the 2018 mudslides helped save lives and homes this year.
Five years ago, 23 people were killed in that disaster that took place not long after a massive wildfire made hillsides in the area more vulnerable.
"The rocks, the trees, any debris that came down from the hills, was captured in those debris basins — the water flowed by — and so we don't have large boulders that took out homes this time like they did in 2018," Favuzzi said.
That said, there's more rain in the forecast for as early as Friday, lingering through Monday. Officials say if conditions warrant, it's possible that evacuation orders will be renewed in Santa Barbara County.
County officials say first responders handled more than 400 emergency calls and six helicopter rescues over the last two days.
Here's what you need to know when storms hit Southern California:
Two waves of heavy rain hit across Southern California, resulting in 87 deaths from floods and mudslides, and "scores" of deaths from car accidents, according to the National Weather Service's summary of the incident.
Hundreds of homes and buildings were destroyed, and Mt. Baldy Village was particularly hard hit, with 14 homes destroyed there alone.
The Los Angeles Times reported that in Silverado Canyon, a fire station filled with mud. Five bodies were recovered there, and 17 people injured.
Local jurisdictions had just finished repairing roads and bridges damaged the month prior, when heavy rains descended again.
Another 21 people died from flooding and mudslides.
Onlooker Arthur Cook recalled his experience later in The New Yorker:
"A wave six to eight feet high came out of Rainbow Canyon. The rock, debris — everything was suspended in the liquid mass. Horrendous boulders, trees, car bodies were suspended in the mass. It sounded like a train–a runaway express train. Just a roar.”
One person drowned in Temecula after heavy rains caused flooding and mudslides, and hundreds of residents were trapped in Topanga Canyon.
Six different storms hit Southern California in just over a week, and 30 people were killed by both floods and mudslides. "Post-fire flooding" caused a basin in Harrison Canyon to overflow four times, and hundreds of homes were either destroyed or damaged.
A mudslide in La Conchita "destroyed nine houses within a few seconds."
"Despite geologists' early warnings to La Conchita residents that the hillside would crumble under heavy rain, scores of homeowners refused to leave," the L.A. Times reported in 1995.
According to a report by the United States Geological Survey, despite the destruction, no lives were lost.
In October that year, wildfires had ravaged the San Bernardino mountains. On Christmas Day, heavy rains led to mud slides, burying a church camp in Waterman Canyon. Twenty-three people had been there for a holiday party, and 13 of them died. Two other victims died in a Devore campground.
In addition to the deadly La Conchita mudslide, five straight days of heavy rains hit other parts of Southern California, causing other mountain slopes to slide and sewage to spill. A pregnant woman in Highland was killed, and a Crestline hotel was destroyed. The total damages were estimated at $100 million, and a state of emergency was declared.
