World's Largest Wildlife Overpass In the Works in Los Angeles County

Caltrans will soon close half of the 101 Freeway in order to continue construction of the Wallis Annenberg Wildlife Crossing near Agoura Hills in Los Angeles County.

2 minute read

April 15, 2024, 9:00 AM PDT

By Clement Lau


Rendering of wildlife crossing over 101 freeway in Los Angeles County.

The Wallis Annenberg Wildlife Crossing will provide a way for animals to cross the 101 freeway. | Annenberg Foundation / Wallis Annenberg Wildlife Crossing

Located at Liberty Canyon and the 101 Freeway, the Wallis Annenberg Wildlife Crossing is a public-private partnership that has leveraged the expertise and leadership of numerous organizations and institutions. The core partners include Caltrans, the National Park Service, the Santa Monica Mountains Conservancy, Mountains Recreation and Conservation Authority, Resource Conservation District of the Santa Monica Mountains, and the National Wildlife Federation.

The purpose of the project is to provide a safe and sustainable passage for wildlife across the 101 Freeway near Liberty Canyon Road in Agoura Hills to reduce wildlife death and allow for the movement of animals and the exchange of genetic material. Without a safe and sustainable wildlife crossing, movement between these remaining areas of natural habitat is severely restricted and wildlife within the Santa Monica Mountains is essentially trapped.

As reported by Makenna Sievertson in this article, Caltrans will be closing all southbound lanes of the 101 Freeway in Agoura Hills for five hours each night for construction on the wildlife crossing starting Monday, April 15th, 2024. Specifically, crews will be installing the first girders, an approximately 100-foot-long box of reinforced concrete that will serve as the base level of the wildlife crossing. The girders will help support the structure’s horizontal reach across one of the country’s busiest highways.

The closure will extend from Liberty Canyon to Chesebro roads, but the northbound lanes will remain open and there will be detours available for drivers. Breaking ground on Earth Day in 2022, the project is anticipated to be completed by early 2026. For additional information, please read the source article.

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