A rendering of what the Wallis Annenberg Wildlife Crossing will look like once construction is complete.
(
National Wildlife Federation and Living Habitats
)
Topline:
All southbound lanes of the 101 Freeway in Agoura Hills will be closed once again overnight Tuesday so construction can wrap up on a major milestone for the Wallis Annenberg Wildlife Crossing.
Why it matters: The northbound lanes will stay open all night, and both freeway and street detours are available for drivers.
Why now: Crews will be removing a large crane that installed 82 girders above both sides of the freeway. The girders, which are huge boxes of reinforced concrete, act as the base level of the wildlife crossing and support its horizontal reach.
The backstory: The last girder was installed over the northbound side Monday night.
What's next: Construction on the Wallis Annenberg Wildlife Crossing, the largest crossing of its kind, is expected to wrap up in early 2026.
Go deeper: Learn more about the wildlife crossing construction and closures.
All southbound lanes of the 101 Freeway in Agoura Hills will be closed one last time overnight Tuesday so construction can wrap on a major milestone for the Wallis Annenberg Wildlife Crossing.
Crews will be removing a large crane from the area, marking the last full nightly closure of all freeway lanes in one direction at a time for the foreseeable future, according to Caltrans.
The northbound lanes will stay open all night, and both freeway and street detours are available for drivers.
What drivers should know
The full southbound closure will start at Chesebro Road at 11 p.m. Tuesday, but some lanes may start to shut down as early as 7 p.m., according to Caltrans.
People are being encouraged to avoid delays by taking an all-freeway detour around the area.
The freeway detour for both the southbound and future northbound closures on the 101 Freeway.
(
Caltrans
)
But if you don’t, you’ll be directed off the freeway along with all the other southbound traffic to the local street detour. Drivers will have to head south on Chesebro Road, east on Agoura Road, and north on Liberty Canyon Road to get back to the 101 on-ramp.
All lanes are expected to reopen by 4 a.m. Wednesday. This closure is expected to last one night, not several weeks like the previous rounds of work.
About the construction
Crews will be removing a large crane that installed 82 girders above both sides of the freeway. The girders, which are huge boxes of reinforced concrete, act as the base level of the wildlife crossing and support its horizontal reach.
The work started on the southbound side last month, then it moved to the northbound lanes, bringing its own set of five-hour overnight closures each time.
The last girder was installed over the northbound side Monday night.
Beth Pratt, the regional executive director of the National Wildlife Federation’s California Regional Center — who also sits on the leadership team of the #SaveLACougars campaign with her P-22 tattoo — said on social media she was also able to sign the final piece before it was added in.
How you can stay updated
Construction on the Wallis Annenberg Wildlife Crossing, the largest crossing of its kind, is expected to wrap up in early 2026.
You can find more information about the project here, and look at a few different livestream angles of the progress here. The next step will be installing a concrete deck over the girders, according to Caltrans.
You can sign-up for free weekly updates by sending an email to Caltrans at D7inquiries@dot.ca.gov or by calling (213) 897-9372.
Caltrans is also hosting the ninth episode of their “CT Talks” webinar, which are conversations aimed at connecting people to others within the department, focused on wildlife crossings at 12 p.m. Thursday. A pair of senior environmental scientists will speak, and you can register for the event here.
