Wallis Annenberg Wildlife Crossing

The Wallis Annenberg Wildlife Crossing (formerly Liberty Canyon Wildlife Crossing) is an under construction vegetated overpass spanning the Ventura Freeway and Agoura Road at Liberty Canyon in Agoura Hills, California. Once completed, the bridge will be one of the largest urban wildlife crossings in the world, connecting the Simi Hills and the Santa Monica Mountains over a busy, 10-lane freeway.
The bridge is meant to allow animals to circulate through and thrive in habitats that are fragmented by human development. The crossing is particularly critical for the mountain lions of the Santa Monica Mountains, which have declined and become genetically isolated because the Ventura Freeway prevents them from moving between the mountains and the Simi Hills to the north. Other species expected to benefit from the crossing include bobcats, coyotes, gray foxes, birds of prey, skunks, rodents, American badgers, American Black Bears, fence lizards and Mule deer.
In 2020, wildlife biologists found the first evidence of physical abnormalities in the isolated population. Newcomers would bring new genetic material into the mountains where the lack of genetic diversity is a serious threat to their long-term survival. It would allow young mountain lions born in the Santa Monica Mountains the chance to find new territory before possibly being killed by one of the dominant older males.
Freeway traffic is one of the primary threats to mountain lions' survival in Southern California. Since 2002, at least a dozen have been killed by motorists on the section of freeway paralleling the Santa Monica Mountains. GPS tracking collars show that most mountain lions approach this area and turn back without attempting to cross, while only one was able to repeatedly cross.
This will be the first bridge on the California highway system designed specifically for fostering wildlife connectivity. The Ventura Freeway is a heavily travelled commuter route serving the Greater Los Angeles area and connecting Los Angeles and Ventura Counties with about 300,000 cars a day. The site is about 35 miles (56 km) northwest of downtown Los Angeles.
Scientists identified Liberty Canyon as the best location for a wildlife crossing in a 1990 study commissioned by the Santa Monica Mountains Conservancy. Acquisition by the conservancy and other partners of privately owned land began to create one of the few areas with the lands on both sides of the freeway that are publicly owned and protected. The crossing is situated along a wildlife corridor within the Santa Monica Mountains National Recreation Area that consists of thousands of acres of local, state and federally protected lands and stretches northerly from Los Angeles into Ventura County. The county of Ventura has adopted a wildlife corridor protection ordinance that restricts activities that will impede the movement of mountains lions and other wildlife between the Santa Monica Mountains and the Los Padres National Forest.
In 2015, the Resource Conservation District of the Santa Monica Mountains published a design for a 165-foot-wide (50 m) and 200-foot-long (61 m) overpass for the wildlife crossing. To encourage use by wildlife, the bridge will have lush but drought-tolerant vegetation with matte materials to deflect bright headlights and insulation to quiet the roar of cars. Fencing at each end will help funnel them onto the crossing. A second phase of the project will cross a frontage road that is parallel with the freeway.
Landscaping of the nearly 1-acre bridge (0.40 ha) includes 12 acres (4.9 ha) of habitat restoration in the area. The restoration is partially needed because the 2018 Woolsey Fire burned through the wildlife corridor as it was pushed by strong Santa Ana winds in a southerly direction, and crossed the freeway in this area.
The draft environmental document was released in 2017. A tunnel was considered as an alternative, but it would be less able to attract usage by wildlife and wouldn’t sustain vegetation. The California Department of Transportation (Caltrans) oversaw design and construction as it crosses a major transportation route.
In 2014, the National Wildlife Federation, the Santa Monica Mountains Fund, and the #SaveLACougars campaign began to raise money for the project. The inspiration for the project, as well as the funding drive's "poster puma", was P-22, a mountain lion that survived crossing two freeways, the 101 and the 405, to reach Griffith Park at the easterly end of the Santa Monica Mountains. P-22 became a local celebrity; his death in 2022 would further stimulate awareness and funds for the campaign.
In 2014, the California Wildlife Conservation Board gave a $650,000 grant to the Resource Conservation District of the Santa Monica Mountains for the design of the crossing.
In 2015, the California Coastal Commission gave a $1 million grant to Caltrans for environmental assessment. Private donors were encouraged to contribute. The project stalled for years due to lack of funding. In May 2021, the Annenberg Foundation pledged to donate another $25 million once the project raised $35 million. As of mid-April 2022, donations totaled more than $87 million, with more than 5,000 people, foundations, agencies, and businesses contributing expertise and donations.
The project costs around $90 million, with funding from private donations covering about 60% and the rest coming from public funds set aside for conservation purposes.
A groundbreaking ceremony was held on Earth Day in April 2022 with Governor Gavin Newsom, Wallis Annenberg, wildlife biologists and members of the public along with local, state and federal legislators. Caltrans set the beginning of construction for spring 2022 with construction to be completed within two years. Initial work included moving public utilities. As of mid-2024, the work is expected to finish by early 2026.