Photo: Will Kohlschreiber, KFI In The Sky
AGOURA HILLS (CNS) - Construction crews successfully installed the first girder and initial level of a wildlife crossing over the Ventura (101) Freeway in the Liberty Canyon area near Agoura Hills, officials announced Wednesday.
Construction of the crossing, in which crews will install massive concrete beams over the roadway, will prompt overnight freeway closures for the next several weeks.
When completed, the crossing will be the largest of its kind in the world, a first in California, and a model for urban wildlife conservation, wildlife 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 girder installation process began Tuesday at 11 p.m. and required the overnight closure of all southbound lanes on the Ventura Freeway between Chesebro and Liberty Canyon roads in Agoura Hills. Closures will take place Monday through Friday -- for five hours every night -- through the duration of the girder placement process. Only one direction of the freeway will be completely closed at a time. All lanes in the opposite direction will remain open for traffic.
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, or girders, constitute the first level of the wildlife crossing's span across one of the nation's busiest freeways. The girders that will be installed over the southbound lanes are each more than 93- feet long and weigh over 126 tons. Each girder that will be placed over the northbound lanes is 103-feet long and weighs 140 tons.
For context, the weight of just one girder is equivalent to the weight of more than 14 African elephants, experts said.
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. The crossing will be the largest of its type in the nation, officials said.
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 at www.101wildlifecrossing.org.