The latest storm to soak the Bay Area has left concerns about the risk along some of the region's hillsides.
Several landslides caused traffic problems on Friday and United States Geological Survey scientists are continually monitoring the area's hillsides.
"The USGS will communicate, essentially, to the National Weather Service what kind of soil moisture level conditions we're seeing at these monitoring stations and then the National Weather Service is responsible for potential watches and warnings that would be associated with possible landslide activity," said Matthew Thomas with the USGS landslides hazards program.
The USGS has monitoring stations strategically scattered around the Bay Area in landslide-prone areas. The agency also has years of monitoring data to compare with real-time data, which helps determine if there an increasing risk.
"Those stations record information like rainfall, soil moisture, groundwater pressure," Thomas said. "Essentially, the ingredients of hillside hydrology that are relevant to landslide initiation for shallow landslides in the Bay Area."
Meanwhile, Caltrans crews spent Friday working to clear southbound Highway 101 in Sausalito after a huge chunk of the steep hillside came sliding down around 7 p.m. Thursday during the heavy rain.
"The slide is still moving a little bit, there’s still a significant amount of material that we’ve got to get out of here," Caltrans spokesperson Bart Ney said. "We’re going to have to have our geotech experts come and take a look at the hill to see if there’s some long term stuff that we need to do."
In San Francisco, a chunk of Telegraph Hill slid into the street below.
No injuries were reported in both the Sausalito and San Francisco landslides.
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