SR-78 Asset Management Project

$133 million in improvements have been planned and are anticipated to be implemented along eastbound and westbound SR-78. Activities include pavement resurfacing, bridge rails, ADA ramps, culvert restoration, and a new westbound auxiliary lane between Nordahl and Twin Oaks Valley roads in San Marcos. Intelligent Transportation System technology improvements will help prepare for an automated future, improve traveler information, and reduce congestion and emissions.

Caltrans completed construction on eastbound and westbound auxiliary lanes between Twin Oaks Valley Road and East Barham Drive in 2018.

To stay up to date with SR-78 projects, please visit to sign up for updates. 

For any questions or comments on projects on the SR-78 corridor, please contact the project team by emailing, and a team member will respond to you promptly.