Burn Areas At Most Risk From Storms
KESQ.com News Services
LOS ANGELES -With more rain expected today on saturated, fire-denuded mountainsides, officials from the U.S. Geological Survey and other agencies are warning evacuated residents to stay out of foothill homes below the site of the Station Fire.
“Based on all the rain we’ve had this week, if we get showers of any intensity there’s still a chance of debris flows from the Station burn areas,” Oxnard-based National Weather Service meteorologist Curt Kaplan said today.
“We do have potential for 2 to 4 more inches of rain in the mountains today,” Kaplan said, adding that with a fast-moving thunderstorm, it may not take much to trigger slides.
Evacuation orders issued to the residents of more than 750 homes in the foothills remained in effect today. The evacuated areas of Little Tujunga, La Crescenta, La Canada and Glendale are in Los Angeles county and city jurisdictions.
Earlier this week, debris flows 8 feet to 12 feet high destroyed USGS monitoring equipment in Dunsmore Canyon, USGS scientists in Pasadena said.
In a statement headlined, “Southern California residents urged to heed evacuation orders as rain continues,” USGS debris flow specialist Susan Cannon evoked previous deadly storms in Southern California.
“The forecast rainfall for the next 48 hours is comparable to that which occurred during a 1969 storm that triggered landslides, debris flows and floods throughout Southern California, resulting in the deaths of 34 people,” Cannon said.
“Because the hills above Glendora had been burned the previous fall, that area was particularly hard hit during the 1969 storm,” Cannon said.
The storm forecast through today is also similar to the Christmas Day storm of 2003, which triggered debris flows from nearly every watershed burned by the Old and Grand Prix fires in the San Bernardino mountains, resulting in widespread destruction and the deaths of 16 people, according to the USGS.
The warning might seem like overkill to evacuation-weary foothill residents. But an aging flood-control system of debris basins and channels offers only partial protection below the burned areas, according to the Los Angeles County Department of Public Works.
Slope failures and debris flows are possible in some cases up to 72 hours after rains on burned areas, according to the Los Angeles County Fire Department.
“In Southern California, debris flows and floods have over history killed a comparable number of people as earthquakes,” said USGS seismologist Lucy Jones. “These past deadly debris flows highlight that residents should not be complacent, and those with evacuation orders need to leave.”
