Big Rock Landslide Still Lurking Underneath Eastern Malibu Homes, Above PCH
Written by 991KBU on November 10, 2020
What to do about the Big Rock landslide?
Some 327 properties at Malibu’s eastern end sit on a mesa that sits atop an underground drainage area from the surrounding mountains.
In fact … the wells that used to supply malibu with much of our drinking water used to be at Big Rock Mesa.
But starting in 1983 … Big Rock Mesa began sliding towards the ocean.
A series of wells and pipes has sucked a large amount of water out of the ground … and the underground water levels have dropped … ending the immediate threat to the homes on Big Rock Mesa.
But new houses … and significant home additions … is not allowed.
Last night … the city council got an update on the special tax assessment district that operates the dewatering system.
Engineer Michael Phipps told them that the safety codes require a safety factor that is 1 and a half times what is necessary to guarantee that buildings won’t slide.
NEWSCART 73098 BIGROCK PHIPPS
“I think that the factor of safety of 1.5 … the landslide has never had that and it’s probably never going to have that.
“The factor of safety was determined in the Binion [spelled phonetically] Report in 1992 and so they’re all different so there’s been some concern about some areas being lower (factor of safety) than others.”
City council members said last night that the safety of homes on Big Rock Mesa need to be monitored.
And that the residents who live there should consider taxing themselves to improve the wells and pipes and meters that handle the water removal.
Councilman Skylar Peak.
NEWSCART 73097 BIGROCK PEAK
“So I think the first thing for me that comes to mind with this just like got a concern of public safety is is it safe or not.
“And I think that sort of based on the report that we got it indicates that while there may have been a little bit of movement the water seems to be relatively stable.”
Big Rock residents are still worried about the ground below their feet possibly shifting.
And the moratorium on new houses … or house additions … will have to be strictly enforced.
Residents on Big Rock might be asked if they want to form a new assessment district … with a higher property tax … to improve the geologic stability beneath their homes.