Caltrans will close a 3.6-mile stretch of Topanga Canyon Boulevard between Pacific Coast Highway and Grand View Drive starting at 5 p.m. Wednesday in advance of predicted rainstorms and potential debris flows.
The closure comes after Christmas storms last week brought mud and debris flows onto State Route 27 and minor damage to Pacific Coast Highway. Caltrans officials said they are concerned about additional damage on both highways, where slopes are already saturated.
Crews will monitor road conditions daily and provide updates on reopening when available.
The National Weather Service is predicting significant rainfall starting Wednesday night, with peak intensities between 10 p.m. Wednesday and 10 p.m. Thursday. Additional rain chances continue through Saturday.
Rainfall totals could reach 3.75 inches in the Palisades Fire burn scar area, with local rain rates of 0.25 to 1 inch per hour, according to the weather service. Officials warn of potential mud and debris flows and isolated flash flooding.
The Palisades Fire recovery work zone on Pacific Coast Highway from Sunset Boulevard to Carbon Beach Terrace will remain open, with crews on standby to respond to flooding and debris flows.
Caltrans crews are preparing by moving equipment, placing K-rail and sandbags, and stabilizing retaining walls and other project work on SR-27 and PCH.
The affected stretch of SR-27 is an active work zone for ongoing Palisades Fire and winter storm recovery efforts. It is normally closed to the public from midnight to 5 a.m. daily.
Travelers should plan alternate routes and avoid driving through burn scar areas during rainstorms, officials said.