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
• Empowering local communities and organizations
• Scientific research
• Creative media


Our Urban Wildlands Program:

• Successfully challenged Newhall Ranch a proposed new town of more than 60,000 residents on a 12,000 acre site in northern Los Angeles County along the Santa Clara River. The massive development, if allowed to move forward, would destroy habitat for many rare plants and animals, impair the last free flowing river in Southern California while sustainably contributing to climate change. In response to a Center lawsuit, the California Supreme Court ruled that the California Department of Fish and Wildlife had inadequately analyzed the proposed development anticipated 260,000 metric tons of annual GHG emissions, illegally permitted take of the fully protected unarmored threespine stickleback and improperly disregarded comments by Native American tribes about the impacts on cultural resources and steelhead. As a result, developers must go back to the drawing board and craft a project that complies with CEQA and the State's efforts to curb climate change.

• Fought back against a controversial project by the California Department of Transportation (“Caltrans”) to widen Highway 1 in Pacifica. In September 2016, a Federal District Court ruled that CalTrans violated the Endangered Species Act by attempting to use an already preserved parcel of land as mitigation for impacts to endangered San Francisco garter snakes and threatened California red-legged frog resulting from the project.  This decision sent a clear message to agencies that they will be held accountable for project approvals and they cannot continue to rely on uncertain and unproven mitigation measures to compensate for irresponsible transportation planning

• Protected San Diego County's water supply, fire safety, and traffic situation as well as habitat for Quino checkerspot butterflies and San Diego fairy shrimp by winning a series of court decisions regarding Fanita Ranch in 2012 that stopped a massive housing project on 2,600 acres of undeveloped chaparral, coastal sage scrub and vernal pool habitat. 

• Successfully protected essential habitat of the Stephen's kangaroo rat and an important regional wildlife corridor in the Sycamore Canyon Wilderness Park and March Stephens' Kangaroo Rat Preserve through a series of lawsuits against multiple proposed development projects (including the Allessandro Business Park and March Air Force Base land swap). After our victories in court, developers and local agencies agreed to significant design changes and enhanced mitigation to protect this area's unique biodiversity.

• Protected the Inland Empire region's air quality, reduced further clogging of its roads, and preserved essential habitat adjacent to the biodiversity hotspot of the San Jacinto Wildlife Area through successful litigation in 2012, which stopped a sprawling development — the Villages at Lakeview — that would have placed 11,350 residential units and 500,000 square feet of commercial space far from existing development.  

• Improved the outlook for tule elk, steelhead trout and other native wildlife by negotiating an enhanced conservation agreement for two already-approved quarry projects in the Sunol area in Alameda County: Apperson Ridge and Sunol Quarry .

• In a series of court victories, stopped more than half a dozen destructive San Bernardino Mountains development proposals in 2005–2008, which compelled developers and public agencies to more seriously consider the legal protections afforded the region's imperiled endemic species. Also, in 2013, the Center successfully negotiated a pre-litigation agreement to protect important pebble plains plant habitat from a proposed housing project in the city of Big Bear. The Center's early and intense involvement in this region has yielded major benefits: Since our 2008 court victory that halted the proposed Hawarden project, the Center hasn't gone to court once in this region.  

• Successfully challenged San Diego County's multi-species habitat conservation plan in 2006 on the grounds that it would result in unpermitted destruction of vernal pool habitat across the county. The federal court ruling in our case had great impact across San Diego County, halting sprawl development projects and forcing the county to abandon its one-size-fits-all “get out of jail free” card for the destruction of vernal pools.

Get the latest on our work for biodiversity and learn how to help in our free weekly e-newsletter.


Check out this KTVU TV video featuring an interview with the Center's Urban Wildlands Staff Attorney John Rose.


SoCal Wild: Southern California's rich biodiversity faces tremendous pressure from a longstanding culture of sprawl and an economy of speculative development. We challenge runaway growth and faulty planning.

Bay Area Wild: We protect biodiversity and open space in the Bay Area and Northern California for a diversity of species, protecting imperiled animals and plants while fighting bad growth.

Water Supply: Water fuels sprawl in California. We won't let private interests take control of this essential public resource to the detriment of wildlife, ecosystems and the state's future.

CalTrans Watch: We lead a statewide coalition taking on irresponsible, damaging California highway-widening projects — which destroy needed habitat and aid climate change. 

CEQA Works: We're fighting to defend the California Environmental Quality Act, which has provided the public with an essential voice and forced decision makers to confront the environmental impacts of proposed projects.

The Endangered Species Act
So Cal Wild
Bay Area Wild
Water Supply
CalTrans Watch
CEQA Works
Apperson Quarry Conservation Agreement
Big Bear Lake and Lake Arrowhead
Cadiz Project  
Monterey Plus Amendments  
Presidential Substation Project 
Restoring Sharp Park, California 
Save Tejon Ranch 
Saving Richardson Grove 
Southwest National Interest Electric Transmission Corridor 
Sunrise Powerlink 
Transmission Lines 
Population and Urban Wildlands

Arroyo toad
Bald eagle
Bay checkerspot butterfly
Cactus ferruginous pygmy owl
California condor
California tiger salamander
Coastal California gnatcatcher
Florida panther
Pacific pocket mouse
Peninsular bighorn sheep
Pima pineapple cactus
San Bernardino kangaroo rat
San Joaquin kit fox
Tehachapi slender salamander
Tucson shovel-nosed snake
Western burrowing owl

+ photo credits

Banner photo courtesy Army Corps of Engineers