Construction of a wildlife crossing will require overnight closures of the southbound 101 Freeway near Agoura Hills in northwest Los Angeles County, Caltrans announced this week.
Crews installed the first girder and initial level of the crossing Tuesday. When completed, the crossing will be the largest of its kind in the world and a model for urban wildlife conservation, advocates said.
“Watching the first horizontal girder placed over the freeway tonight, surrounded by our championship team of partners who helped make the Wallis Annenberg Wildlife Crossing a reality, was cathartic,'' Beth Pratt, California regional executive director for the National Wildlife Federation, said in a statement.
“We all cheered when the crane lowered the first concrete beam across the freeway, as we truly saw the bridge starting to take shape. This structure is a testament to us all wanting a future for wildlife and mountain lions in the Santa Monica Mountains.'’
The process of installing all the girders -- 82 in total -- across all 10 freeway lanes is expected to take from 30 to 45 days to complete.
The large concrete beams constitute the first level of the crossing’s span across one of the nation’s busiest freeways. The girders over the southbound lanes are each more than 93 feet long and weigh over 126 tons. Each girder over the northbound lanes is 103 feet long and weighs 140 tons.
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.
Construction on the wildlife crossing began in 2022, and is expected to be completed by late 2025 or early 2026.
The fully landscaped crossing 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.
