Mandatory evacuation orders had been issued for parts of Duarte and voluntary evacuation orders were issued for parts of Camarillo Springs as a massive storm barreled down on the region Friday.
Residents of 202 homes in the Fish Fire impact area of Duarte were ordered to evacuate by 7 a.m. Friday.
Mud was breaching the barriers by Friday evening, flowing down Mel Canyon Road but no significant damage to homes was reported.
The mud overflowed past one row of K-rails set up at the top of Mel Canyon Road and was starting to overtake a second row.
The 20-foot K-rails each weigh about 8,000 pounds.
Crews had spent days preparing the area for the expected flood, cleaning out catch basins and setting up the two rows of barriers.
In the past, this neighborhood has seen K-rails pushed out of the way by mud flows that reached as high as 4-5 feet.
An evacuation center was established at the Duarte City Hall Community Center, located at 1600 Huntington Dr. The impact of the coming rain was predicted to be even stronger than the storms last month that caused flash flooding throughout Southern California.
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Valley View School in Duarte was closed Friday and city trash collection was postponed until Monday.
More information about the Duarte evacuation is available here.
In Camarillo Springs, voluntary evacuation orders were in effect from 8 a.m. until 10 p.m. on Friday.
Those who evacuate the area can head to the recreation center in Leisure Village to seek shelter. The address is 1200 Leisure Village Dr.
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Ahead of the storm, a yellow alert was declared for residents near the Colby Fire burn area in the the city of Glendora.
Residents in the area must move vehicles, trash bins and other objects from streets to allow access for emergency vehicles, and to prevent them from being washed away by possible flooding.
Crews scrambled to clean out debris basins at the base of the foothills throughout the San Gabriel Valley before the monster storm hit.
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The Fish Fire of 2016 scorched the foothills, leaving communities like Duarte vulnerable to mud and debris flow during heavy rain.
The main defense against rivers of mud and debris slamming into homes are debris basins at the foothills.
"We have about 175 debris basins strategically placed throughout the foothills," Bob Spence with the Los Angeles County Department of Public Works explained. "These debris basins represent our first line of defense when it comes to debris, mud flow and mudslides. The increase of that is heightened after we've had wildfires like the Fish Fire."