Neighbors in Baldwin Hills could only watch with that helpless feeling Monday when a hillside behind their homes slowly gave way and mud, rocks and debris flowed into their backyards.
Many heard the slide, triggered by nonstop rain from a storm that arrived Sunday in Los Angeles, before they saw the unstoppable wall of mud.
Mark Alston said he and his wife were watching a movie when he heard the ominous sound.
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"It sounded like thunder," Alston said.
The mudslide that started around 4 a.m. Monday gradually expanded to entire backyards, bringing rocks, trees and other debris with it.
"When we heard the crash, I was like, 'If I don't see it, it's not happening,'" said resident Dion Peronneau. "It was 2 feet, 3 feet. Now, it's this.
A pile of mud and debris collected against her house and pushed through a sliding door entrance to her bedroom.
Alston has lived in the South Los Angeles community for more than 20 years. After a storm 13 years ago, he put up retaining walls to protect his property.
"The retaining walls seemed to have worked, but they needed to be extended," he said, referring to mud that wrapped around the end of the wall. "They needed to go wider. This went around the retaining walls."
More rain is in the forecast Tuesday before the storm begins to break up Wednesday. Many areas of Los Angeles have already seen a month's worth of rain in just two days, leaving hillsides saturated and prone to slides.
The storm brought more rain to downtown Los Angeles, about 8 miles east of Baldwin Hills, than the area typically receives for the entire month of February. Downtown Los Angeles received nearly 7 inches of rain by Monday night, nearly half the yearly average of 14.25 inches.
