AGOURA HILLS, Calif. — Construction of a wildlife crossing over the Ventura (101) Freeway in the Liberty Canyon area near Agoura Hills will enter another phase next week, as crews begin installing massive concrete beams over the roadway, prompting overnight freeway closures for the next several weeks.
The closures will begin Monday night on the southbound side of the freeway between Cheseboro and Liberty Canyon roads, starting at 11:59 p.m. and continuing through 5 a.m. Tuesday. The overnight closures will be repeated Monday through Friday.
The closures are necessary for crews to lift and install large concrete beams, or girders, over the freeway. Each of the girders weighs between 126 and 140 tons, stretching from the center median to the freeway shoulder, according to Caltrans.
Once the girders over the southbound side of the freeway are installed, the overnight closures will shift to the northbound side, conducted during the same hours.
Caltrans officials said the overall girder operation is expected to take six to eight weeks. A total of 82 girders are expected to be installed.
"We are very excited to celebrate this big milestone in the construction of the Wallis Annenberg Wildlife Crossing. With the placement of the horizontal supports, the structure is truly going to start looking like the bridge it will become," Beth Pratt, California Regional Executive Director for the National Wildlife Federation, said in a statement. "We know that closures of the freeway do have impacts on traffic and the community, and we apologize for any inconvenience this may cause.
"Caltrans has a thorough plan for detours, and we trust their excellent team to manage this to minimize disruption. And these `Closures for Cougars' are for a good cause — helping to save the area mountain lions from extinction and ensuring a future for all wildlife in the Santa Monica Mountains."
Caltrans officials said motorists who need to traverse the area during the closure hours should consider using the Ronald Reagan (118) Freeway as an alternate between state Route 23 and the San Diego (405) Freeway. More localized detours on area streets will also be in place.
Officials with Caltrans and the National Wildlife Federation will host a community meeting at 6:30 p.m. Thursday to provide information about the upcoming closures and the status of the crossing project. The meeting will be at Agoura Hills City Hall, 30001 Ladyface Court.
Construction on the wildlife crossing began in 2022, and it is expected to be completed by late 2025 or early 2026.
The fully landscaped crossing will span over all 10 lanes of the freeway. It is designed to provide a connection between the small population of mountain lions in the Santa Monica Mountains and the larger and genetically diverse populations to the north.
Decades of road construction and development have been deadly for animals trying to cross the area's freeways, while creating islands of habitat that have genetically isolated wildlife ranging from bobcats to birds and lizards.
Wildlife advocates hope the crossing can save the threatened local population of mountain lions from extinction, which could become inevitable if lions continue a historic pattern of inbreeding due to the limited numbers of cats in the area.
More information about the project is available online at www.101wildlifecrossing.org.