Caltrans TCB Closure Update 5-10-24

TCB Road Closure 5 10 24

UPDATE 5/10: Topanga Canyon Landslide at Postmile 1.8 on SR-27

  • Caltrans is replacing a dirt berm and silt fence that protects Topanga Creek with a rock fence due to concerns about dirt falling into the environmentally sensitive creek during slide removal. K-rails have been installed and cyclone fence is being placed atop the k-rails to form a rock fence designed to stop rocks and boulders from falling into the creek that is home to fish and other wildlife. The cyclone fence installation is expected to be completed soon.
  • Caltrans is reviewing a draft geotechnical report and consulting with partner agencies before final approval. The geotechnical report will provide recommendation on how to stabilize the slope.
  • Geologists and the contractor have determined that the face of the 300-foot-tall landslide is too loose and unsafe to approach head on so a side road that zig zags left of the slide area must be built to move equipment to the top of the hillside. This roadwork is expected to be built soon and will take several days. This is a dangerous procedure that could bring down more material, so no one will be allowed in the area.
  • Once this road is built, the plan is to remove the landslide from the top, pushing material down to the roadway where trucks will be hauling away the dirt, rocks and boulders to an undetermined location.
  • Fountain Grass, a non-native invasive plant, will be removed in coordination with the contractor’s preparation for a path to remove the slide. Its seeds are carried long distances in the wind. It is especially dangerous in fire hazard areas because it dries out early in the summer and becomes flammable. At the direction of the biologist, the contractor’s equipment must be thoroughly washed to prevent seeds from other sites drifting onto the hillsides.
  • The landslide has not moved in some time and is not expected to move further if the warm, dry weather continues. This is an indication the landslide has become more stable.
  • Gov. Gavin Newsom proclaimed a state of emergency on May 3 to help fund badly needed repairs of roads battered during this year’s storms, including State Route 27 (Topanga Canyon Boulevard).The proclamation enables Caltrans to request funding from the Federal Highway Administration’s Emergency Relief Program, which could cover up to 100% of the repairs, according to the governor’s office. This declaration does not speed up the process for slide removal, which is dependent upon geological conditions, not funding.
  • Caltrans realizes the Topanga community is very concerned about the upcoming fire season. Los Angeles County Fire Department (LACFD), Los Angeles County Sheriff, CHP and Caltrans coordinate possible evacuation routes depending on the situation. LACFD typically takes command during incidents and coordinates the response from first responders or external agencies, including Caltrans. Historically, Caltrans and CHP will close outside access into Topanga Canyon from PCH and the San Fernando Valley to allow residents to evacuate. Caltrans at times has assisted LACFD with watering trucks and equipment. We recommend reaching out to LACFD for additional questions on evacuations.
  • Caltrans is aiming to open the roadway by fall 2024.
  • SR-27 remains closed from Grand View Drive to Pacific Coast Highway (Route 1).