The Center's Urban Wildlands Program focuses on private land development, water-supply projects and highway building in the “wildland-urban interface” — the edges of sprawling urban and suburban areas adjacent to wildlands.

It's in these places that endangered and threatened species and their habitat — and biodiversity in general — are particularly at risk due to unchecked sprawl. We bring our expertise in land-use law, water law and biology to bear on projects that threaten to tear up habitat, create pollution, exhaust water supplies and drive extinctions. Our goals are to stop unsustainable sprawl in its tracks and empower our local allies, while encouraging and working with local planners and developers to appreciate and protect the rich biodiversity of their communities. 

Click dots on the map for more information on past (blue) and present (red) Urban Wildlands projects. Zoom in for more detail of project boundaries, or view the full-page version.



• Strategic lawsuits
• Participation in public review processes for projects
• Building and participating in local and state-wide coalitions
• Advocating for land-use policies that protect people and wildlife
• Empowering local communities and organizations
• Scientific research
• Creative media


Our Urban Wildlands program ...

  • In 2021 secured a legal agreement with a Placer County development that won key measures to cut greenhouse gases, along with funding for electric vehicles, habitat acquisition and conservation efforts in the county and beyond.
  • Building upon a California Supreme Court win, achieved a historic 2017 settlement with megadevelopment Newhall Ranch  preserving thousands of acres of wildlands, requiring stringent emissions-reduction measures, and reducing impacts on  vulnerable wildlife like the unarmored threespine stickleback and San Fernando Valley spineflower.
  • Secured protections for Southern California steelhead trout in the Santa Clara River requiring the United Water Conservation District to implement a long-term steelhead passage solution for the Vern Freeman Dam and release sufficient water downstream for steelhead migration.
  • Repeatedly challenged and won courtroom victories against the World Logistics Center, a Southern California warehouse project the size of 700 football fields that would worsen Riverside County's air quality, harm wildlife in the San Jacinto Wildlife Area, and emit almost 400,000 metric tons of greenhouse gases every year.
  • Pushed Ventura County to adopt a first-of-its-kind ordinance to safeguard wildlife connectivity from new roads and development.
  • Brokered a legal agreement requiring the developer behind the planned Altair project in western Riverside County to increase protection of a critical corridor for local mountain lions and other wildlife, fund restoration efforts, and ensure implementation of a regional conservation plan. The agreement ensured that our courtroom victory against Altair would result in permanent protections for rare species.
  • Halted Walt Ranch, a proposed vineyard project in Napa County that would have torn down 14,000 trees and destroyed habitat for California red-legged frogs with a victory in the California Court of Appeals. Walt Ranch will now have to do much more to reduce its greenhouse gas emissions before moving forward.
  • Successfully challenged Tejon Ranch Company’s proposed 8,000-acre Grapevine development, which would destroy habitat for 36 rare plants and animals — like San Joaquin kit foxes, blunt-nosed leopard lizards and San Joaquin antelope squirrels — and add thousands more cars to local highways. Grapevine is part of a larger Southern California development proposed by Tejon that includes Centennial and Tejon Mountain Village, also part of ongoing legal challenges.
  • Beat back the “Harmony” development, a proposed Southern California sprawl project that would have threatened endangered species habitat, rare wetlands and crucial wildlife connectivity while bringing more air pollution and traffic to the community of Highland. Our legal challenge resulted in a courtroom ruling rejecting the project’s environmental review as inadequate and rescinding project approvals.
Banner photo courtesy Army Corps of Engineers