Highways connect us, but also divide the land and create barriers to safe passage for both wildlife and people. In the Santa Cruz Mountains, California state highway 17 (Highway 17) fragments thousands of acres of open space, limiting the ability of wildlife to find food, mates and habitat, as well as preventing the completion of several regional trail systems. Together with private and public partners, neighbors and District constituents, Midpen is exploring the feasibility of developing two independent road crossings - a wildlife undercrossing and recreational trail overcrossing - to link over 30,000 acres of protected public lands.
The project also includes directional fencing that will help animals safely find their way to the wildlife crossing and a number of regional trail connections that will link the following Santa Clara County parks and Midpen open space preserves together across Highway 17: Sanborn County Park, El Sereno Preserve, Lexington Reservoir County Park, St. Joseph's Hill Preserve, Sierra Azul Preserve and Almaden Quicksilver County Park.





Goals
- Link over 30,000 acres of habitat and protected public lands on both sides of Highway 17, including Midpen preserves (El Sereno, St Joseph's Hill and Sierra Azul) and Santa Clara County Parks (Lexington, Sanborn and Almaden Quicksilver)
- Improve motorist safety by reducing the potential for collisions with wildlife
- Maintain healthy wildlife populations
- Provide two structures - one for wildlife and one for recreational trail users - that support safe movement across Highway 17
- Connect over 50 miles of existing regional trails, including Bay Area Ridge Trail, Juan Bautista De Anza National Historic Trail and Los Gatos Creek Trail
- Develop a Mitigation Credit Agreement (MCA) to offset potential ecological impacts from construction with project benefits like habitat connectivity
Stay informed!
While wildlife and trail crossings share similar goals, animals and people have unique needs and use crossings in different ways. To meet the requirements of both, two distinct and separate structures have been recommended to cross Highway 17: a wildlife undercrossing and a trail overcrossing. The following locations for each crossing structure are currently under environmental review:
- a wildlife undercrossing at Trout Creek (2)
- a trail overcrossing either south of Trout Creek Canyon (3a) or north of Trout Creek Canyon (5a)

Also under environmental review are conceptual trail routes to the proposed trail crossings from existing trail networks in nearby El Sereno, St. Joseph’s Hill and Sierra Azul preserves, as well as Lexington Reservoir and Sanborn county parks. When completed, these new trail connections will link approximately 50 miles of the existing Bay Area Ridge Trail and 22 miles of the Juan Bautista De Anza National Historic Trail.
Midpen is exploring a Mitigation Credit Agreement (MCA) with the California Department of Fish and Wildlife. An MCA would allow Midpen to offset potential ecological impacts from construction with project benefits like habitat connectivity for species that have been highlighted as priorities by the Santa Clara County Regional Conservation Investment Strategy, including mountain lion, California red-legged frog, American badger and western pond turtle. If benefits outweigh impacts, Midpen may generate excess mitigation credits that can be used by the agency or sold to other entities to offset impacts from their projects. Selling excess credits could potentially be used to help fund the Highway 17 project, both its construction and even long term maintenance, and reduce the overall cost of the project to Midpen, its partners and taxpayers.

Mosaic of support
2016 - 2018 | Feasibility study and revised alternatives report |
2018 - 2019 | Caltrans Project Study Report Regional Trails Connection Study |
2020 - 2023 | Environmental review and Caltrans Project Report Current status: Midpen preparation of Project Approval and Environmental Document (PA&ED) underway |
2021 - 2024 | Mitigation Credit Agreement development phase |
2022 - 2025 | Design phase (plans and specifications) |
2025 and beyond | Bidding and construction (funding dependent) |
Key Partners and Regional Stakeholders
This project requires a high level of coordination and partnership. Partners in this project may include:
California Wildlife Conservation Board
Bay Area Ridge Trail
California Department of Fish and Wildlife
California State Coastal Conservancy
Caltrans District 4
Juan Bautista de Anza Trail (National Park Service)
Metropolitan Transportation Commission
National Wildlife Federation
Pathways for Wildlife
Peninsula Open Space Trust
Santa Clara County Parks
Santa Clara County Roads and Airports
Santa Clara Valley Transportation Authority
San Jose Water Company
Town of Los Gatos
UC Santa Cruz Puma Project
Valley Water
Midpen is continually developing additional partnerships and working with stakeholders to grow this list as the project develops.
Related Documents
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