World's largest wildlife crossing reaches critical milestone. Now what?

Summary

Monday was momentous for the Wallis Annenberg Wildlife Crossing although it still looked like a bridge to nowhere from the 101 Freeway, where more than 300,000 vehicles stream endlessly every day.Nearly three years after the project began, the critical milestone was visible only to the government officials, scientists and longtime supporters who climbed to the top: soil.And not just any soil. Over the next few days they'll be adding 6,000 cubic yards of specially manufactured soil to cover the crossing, a mix of sand, silt and clay inoculated with a bit of compost and hyperlocal mycorrhizal fungi, carefully designed and tested to mimic the biological makeup of native soils around the site.The plan is to add 6,000 cubic yards of soil, contoured at different depths, to the top of the Wallis Annenberg Wildlife Crossing. (Al Seib / For The Times)Adding soil is a big deal because it means we're nearing the end of Stage 1, when the top is seeded and then planted with native shrubs and perennials, work that should be completed this summer, said Robert Rock, chief executive of Chicago-based Rock Design Associates and the landscape architect overseeing the project.But we're still a ways from completion, now scheduled for the end of 2026, about a year later than initially planned due to delays from the heavy rains in 2022 and 2023.Stage 2, the final phase, will connect the structure to the hills at the north and south so that wildlife, like L.A.’s famous, ill-fated cougar, P-22, can use it. That stage will start with burying utility lines along a section of Agoura Road, south of the crossing, and moving water lines for recycled water used for irrigation.Read more: Saving the next P-22 starts with a million ‘hyperlocal’ seeds and a bare-bones nurseryLate in 2025 or early 2026, Agoura Road will be closed for a few months so the roadway can be covered with a tunnel and lots of soil collected from the Malibu Lake area. The goal is to create natural slopes off the crossing — an ad...