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Where Transportation and Wildlife Collide

As urbanization continues in Orange County, the wildland-urban interface is moving and expanding. The wildland-urban interface (WUI) is the zone of transition between unoccupied wildland and human developments. This area becomes particularly sensitive for wildlife as infrastructure such as roads, cell towers, and water facilities disrupt the natural ecology. Due to their close proximity to open spaces, communities are often also more at risk of wildfires. Orange County planners and residents are striving constantly to reconcile the ever expanding need for good ways to enhance traffic flow while ensuring the environment is also carefully respected.

View of the Bond Fire which threatened Orchard Hills, the community that resides in the WUI between Portola Pkwy and Route 241. Photo by Michaela Coats.

In a recent review of the traffic situation in the South County, The Toll Roads and transportation commission (OCTA) provided a report (South County Traffic Relief Effort Project Report) of their research on ways to enhance traffic flow while ensuring a sustainable relationship with the natural environment. The process of creating the report included multiple mobility workshops with leaders from environmental groups such as the Surfrider Foundation, the Endangered Habitats League, and Sierra Club, as well as separate workshops with locally elected officials. These environmental groups work tirelessly to advocate for the environment amidst attempts of infrastructure development that would harm crucial habitats.

OCTA recommended that a coordinated implementation of multiple planned projects should be considered and be able to accommodate the transportation needs. In an attempt to balance the expanding infrastructure with environmental and public health, many factors put forth by the various community resources were considered such as:

1. Effects of toxins from extra traffic near schools from expanding HOV/HOT lanes

2. Cost of the project and tolls is prohibitive for many residents

3. Net effect of not alleviating traffic congestion

4. Perceived possible drop in property values in San Juan Capistrano

5. Possible negative effects of construction noise and construction air emissions that might exceed air quality standards for fine PM10 and toxic emissions during construction that cannot be mitigated to less than significant impacts per CEAQ and the NEPA.

Also taken into consideration in the decision were the Cultural Resource Sites, which include previously recorded archaeological, paleontological, or historic sites documented within the disturbance limits of the alternatives and environmental justice communities, which include the number of census tracts within the disturbance limits of an alternative that may have higher populations than the County as a whole for one, two, or all three of these categories that include:

· higher Latino/Hispanic populations

· higher minority populations

· higher low-income populations

(Of the alternatives only about one-quarter were considered to have a low impact on the environmental justice communities.)

According to the Coastal Commission, the Interstate 5 transportation corridor within South Orange County bisects coastal resources, including environmentally sensitive habitat areas designated as ecological preserves and coastal lagoon systems along the Pacific Ocean. Impacts to these resources are carefully restricted by Coastal Act policies. The Coastal Commission weighed in on the alternatives and urged decision makers to couple any decisions around highway expansions with robust public transit options, as also noted by commenters, to promote reductions in greenhouse gas emissions and improvements to public access to the coast.

It was also recommended CalTrans should prioritize maintaining wildlife movement and habitat connectivity with any new transportation projects as well as enhance such connectivity with projects that include existing transportation infrastructure. Both north-south and east-west movement is vital for healthy populations of mountain lions and other wildlife and plants in the region. They should choose the alternative that minimizes impacts to mountain lions and other wildlife movement, especially in an area in which such movement is already compromised by existing roads and development. The strong link between mountain lions and ecosystem function and public health and safety warrants the integration of wildlife movement and behavior as well as habitat connectivity in the design and implementation of transportation infrastructure like the proposed project.

Wildlife Protection Fence installed along State Route 241. Photo sourced from the OC Register.

To that end, one of TCA’s major environmental initiatives was the completion of the Wildlife Protection Fence along State Route 241 and the ongoing monitoring of the fence’s effectiveness and the associated bridge under-crossings and large culverts efficacy. The 10- to 12-foot-high 6.5 mile fence was constructed to protect mountain lions, mule deer, coyotes and bobcats living in the Santa Ana Mountains from passing cars. In addition to shielding them from the road, the new fence, which spans both sides of a six-mile stretch of SR 241, also funnels them to existing wildlife bridges and culvert under-crossings that allow them safe passage to open spaces on either side of the road. The project was the result of a joint study with University of California, Davis into the movement and health of the area’s wildlife, including GPS tracking of mountain lions, and collaboration with the California Department of Transportation (CalTrans) and the U.S. Fish and Wildlife Service.

Map of MacPherson property purchased by the OCTA. Photo sourced from the OC Register.

OCTA continues to purchase land for use as open space to be permanently designated as wilderness preserves. For example, the 204-acre MacPherson property was purchased about 6 years ago located northwest of Rancho Santa Margarita in the Silverado-Modjeska area because it was identified as a priority conservation area and because of the diversity of habitat types found on the property, including chaparral, coastal sage scrub, oak woodland, and native grassland. This property is adjacent to the Orange County Parks open space properties as well as Irvine Ranch Conservancy wildlands, enabling linkage to other key protected wildlands.

In a world of increasing development, there is an ever-growing need for solid infrastructure development. Finding the balance between development and the environment takes the collaboration between stakeholders where each perspective is taken into account. Together, we can find the sustainable option that benefits both humans and wildlife.

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