Data-Driven Collaboration Moves Forward a Landmark Wildlife Crossing in California
Through data, collaboration, and integrated engineering, the Pacheco Pass Wildlife Crossing advances habitat connectivity along SR-152, using wildlife movement data to guide design and balance ecology with transportation needs.
Achieving Caltrans project approval on complex infrastructure projects takes more than good design; it takes an integrated, data-driven approach from day one.
For the Pacheco Pass Wildlife Crossing along SR‑152, that approach brought together biologists, engineers, and planners to solve a multi-layered challenge: how to restore wildlife connectivity across a major transportation corridor while meeting regulatory and technical requirements. A key component was the use of wildlife collar data and other datasets, including roadkill observations and camera studies, to better understand how species like mountain lions move through the landscape. This data informed a structured, evidence-based process to identify and refine optimal crossing locations, ensuring the project responds directly to real-world wildlife behavior. From there, engineering solutions were developed in parallel, integrating wildlife needs into the design itself. This included coordinating structure placement, landscape integration, and safety considerations to create a crossing that functions as both infrastructure and habitat.
Mark Thomas advanced the project through a phased approach, starting with corridor-level analysis and alternatives screening, and progressing into refined concepts ready for environmental clearance and approval. This iterative process allowed the team to continuously incorporate data, stakeholder input, and agency requirements, reducing risk and streamlining delivery. Through this integrated effort, the project successfully reached PA&ED approval, making this project only the third wildlife crossing to be approved by Caltrans.
At Mark Thomas, we’re proud to help lead this kind of multidisciplinary work, where data, collaboration, and engineering come together to move projects forward.
Thank you to our teaming partners at Santa Clara Valley Habitat Agency, Caltrans, Wildlife Detections LLC, California Department of Fish and Wildlife, California Wildlife Conservation Board, Gordon and Betty Moore Foundation, Wildlife Conservation Network, Karen C. Drayer Wildlife Health Center, UC Davis, Dudek, Circlepoint, Environmental Science Associates, Rana Creek, and subject matter experts Terry McGuire and Tony Clevenger.
