SR 78 serves as the primary east-west travel corridor between Escondido and Oceanside, traversing through Carlsbad, Vista, and San Marcos, as well as unincorporated areas of San Diego County. It is the main route for local and regional travel in North County and provides north-south connections to Interstates 5 and 15.

North County Comprehensive Multimodal Corridor Plan

Currently, SANDAG and Caltrans are working on a North County Comprehensive Multimodal Corridor Plan (CMCP). CMCPs are data-driven plans to reduce congestion and generate transportation choices while preserving community character and creating opportunities for enhancement projects. CMCPs include all travel modes in a defined corridor – roadways, public transit, bikeways, and more.   

Please take our North County Transportation Priorities Survey by April 30, 2021 and share your input!

Additionally, please visit the project’s Virtual Engagement Hub in English and Spanish to submit comments and feedback on our interactive project map.

For more information regarding the North County CMCP and how to participate in upcoming public meetings, visit


Additional SR 78 Corridor Improvements

SANDAG and Caltrans have proposed additional improvements to this corridor, including the I-15/SR 78 Managed Lanes Direct Connectors Project, the I-5/SR 78 Interchange Project, the SR 78 Managed Lanes Project, and operational improvements along SR 78. Other long-term projects include future double tracking and express services for the SPRINTER and the construction of additional segments of the Inland Rail Trail Bike Path.

I-15/SR 78 Managed Lanes Direct Connectors Project 

Virtual Engagement Hub

Spanish Virtual Engagement Hub

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In fall 2019, Caltrans, in partnership with SANDAG and the City of San Marcos, began the environmental process to evaluate Managed Lanes Direct Connectors between I-15 and SR 78.

The project will bring relief to an area of the region that has experienced tremendous residential and job growth over the past 25 years and improvements are expected to improve connectivity and traffic flow on and between two major travel corridors, increase local access to homes and jobs, and improve overall quality of life in North San Diego County.

I-15/SR 78 Managed Lanes Direct Connectors Project

Specifically, the project will improve connectivity by:

  • Building Managed Lanes Direct Connectors between I-15 and SR 78
  • Extending three miles of Managed Lanes in each direction on SR 78 between the interchange and San Marcos Boulevard
  • Adding a westbound auxiliary lane between Nordahl Road and Woodland Parkway/Barham Drive
  • Relocating the eastbound SR 78 on-ramp from Barham Drive
  • Widening and realigning Barham Drive from La Moree Road to Woodland Parkway
  • Replacing the Woodland Parkway undercrossing
  • Constructing a bike facility on Barham Drive/Woodland Parkway

View this project's fact sheets in English and Spanish to learn more.

Public Scoping Period 

In October, Caltrans released the Notice of Preparation (NOP) for the I-15/SR 78 Managed Lanes Direct Connectors Project, which kicked off a minimum 30-day public scoping comment period. Early public feedback on the project is critical to helping the project team develop a comprehensive list of environmental topics to study, ensure community concerns are addressed, and identify opportunities to improve the project. The 30-day public scoping comment period began on Monday, October 19 and ended on Friday, November 20.

During this time, the project team collected nearly 90 public scoping comments, which Caltrans, as the lead agency under the California Environmental Quality Act (CEQA) and the National Environmental Policy Act (NEPA), will take into consideration and summarize in the project’s Draft Environmental Impact Report/Environmental Assessment (EIR/EA).  Key themes heard across the public feedback included general impacts on traffic, traffic patterns on I-15 near the Valley Parkway on- and off-ramps, Managed Lanes operations and pricing, noise, landscaping, air quality, and proposed bike and pedestrian facilities.

Next Steps:

The project team is evaluating the public comments collected during the 30-day public scoping period and taking the feedback into consideration as they begin to evaluate project alternatives, conduct technical studies, and study the impacts the project may have on the environment. The culmination of this work will be summarized and released for public review in the project’s Draft Environmental Impact Report/Environmental Assessment (EIR/EA).

The Draft EIR/EA is expected to be released for public review and comment in summer 2022. A Final Environmental Document is anticipated in 2023. Please view the anticipated project timeline and environmental process below.

Project Timeline and Estimated Costs

The I-15/SR 78 Managed Lanes Direct Connectors project is in the early stages of a three-year environmental review process. Numerous opportunities to provide comment on the project will be available. The Draft­ Environmental Impact Report (EIR) is expected to be released for public review and comment in late 2022 and a Final EIR is anticipated in late 2023. The project has an estimated cost of $450 million and is currently anticipated for construction in 2025, pending funding.

Project Timeline

Related Projects

The project is one component of a North County Comprehensive Multimodal Corridor Plan (CMCP) study being undertaken by Caltrans and SANDAG that uses a holistic approach towards integrating highway, transit, and mobility projects along SR 78.

The proposed connectors are listed as the top priority among direct connector projects in the SANDAG 2050 Regional Transportation Plan