While news coverage of the January wildfires in Los Angeles County focused primarily on the casualties and thousands of homes and other buildings destroyed, it also took a toll on the local infrastructure.
Those fires ravaged areas in the California Department of Transportation (Caltrans) District 7 (Los Angeles and Ventura counties). As the greater Los Angeles area is no stranger to destructive fires, the agency was prepared to act, its officials said.
Marc Bischoff, a public information officer, was part of Caltrans' emergency response team. He witnessed the damage first-hand and the heroism of the many emergency personnel who risked their lives to extinguish the flames and save lives.
"[The fire]-damaged infrastructure includes retaining walls, slopes, guard rails, drainage, signs, traffic signals and traffic control systems," he said.
The main damage is within the burn area of the Palisades Fire, which affected approximately 7.5 mi. along State Route 1 (Pacific Coast Highway) and approximately 3 mi. along State Route 27 (Topanga Canyon Boulevard). This led to extensive damage to gas, electric and water utilities along both routes. There were rock and mudslides along Topanga Canyon Boulevard.
Bischoff said that the asphalt roads held up well to the fire's high temperatures.
As was the case with landslides caused by winter storms and atmospheric rivers in the past two years, Caltrans crews were on the scene quickly.
"Caltrans maintenance crews were immediately dispatched to establish hard closures along both routes to keep the public safe and to allow evacuees to escape," Bischoff said. "Caltrans immediately activated its own emergency operation center that was staffed 24/7. All Caltrans divisions cooperated in securing any necessary equipment, personnel and emergency repair funding. Initial work included repairs to traffic signals and changeable message signs along PCH and removal of fire debris."
Caltrans was one of multiple agencies including law enforcement, fire departments and utility companies that were part of the Palisades Fire Incident Command Center. There were daily meetings and decisions made as a group.
"Caltrans assisted with the removal of post-fire debris, traffic control and the placement of k-rail along PCH to protect surviving homes from runoff during post-fire rainstorms," Bischoff said. "It is the responsibility of local law enforcement to conduct evacuations along neighborhood streets and canyon roads that are not part of the state highway system.
"Caltrans maintenance crews were immediately dispatched to establish hard closures along SR 1 and SR 27 to keep the public safe and to allow evacuees to escape. Caltrans always allows access to responding emergency vehicles. Caltrans' top priority is always safety, and we actively pursue communication with and support for our partner agencies."
Caltrans has initiated repair efforts for its infrastructure.
"Traffic signals are already repaired," Bischoff said. "Additional repair times will vary depending on the infrastructure. Repairing slopes and rebuilding retaining walls will most likely take the longest time."
The difference between the Palisades Fire and previous ones, noted Bischoff, was that an extensive length of highway was impacted.
There are now increased threats of landslides in areas where hillsides were scarred by the fires.
"We have been planning for the impact that winter weather will have and is already having on burn scar areas along PCH and TCB," Bischoff said. "We have been dispatching teams flying drones creating 3-D maps for our geotechnical engineers to determine how to protect our transportation infrastructure and motorists from mudslides, rockfall and debris flow from storms. Caltrans mobilized 385 personnel to Los Angeles County, including 19 civil engineers for emergency watershed protection."
Asked about lessons learned during the recent fires and best practices learned from previous fires that were applied, Bischoff replied: "All Caltrans infrastructure is built or rebuilt to code. Rock scalers are assigned to clear loose debris from damaged slopes and slopes are reconstructed where necessary. Other slope run-off mitigation includes securing netting to the slopes, building retaining walls and placing k-rail. Damaged drainage and guardrail are upgraded where applicable when reconstructed."
On Feb. 7, Caltrans, in coordination with the Los Angeles County Public Works Department (LACPW), determined that the PCH needs to remain closed until further notice for safety, especially with heavy rains forecast.
"Debris flows occurred during [recent] storms, including a significant slide north of Big Rock Drive," according to a Caltrans press release. "A geotechnical assessment observed slippage along the hill below Porto Marina Way. Slides also may occur in between storms after the soil has been softened."
This closure also enhances safety for emergency, utility and waste hauler workers to continue operating in the area.
Much of the work is taking place along the PCH. This includes contractors placing steel plates to protect the slope along Porto Marina Way; the LACPW effort to haul out debris; emergency workers clearing debris from the highway; and the placement of k-rail barriers at key locations.
The closure status will be evaluated on a day-to-day basis, Bischoff said.
(All photos courtesy of the California Department of Transportation.)
