The Baker-Barry Tunnel, stretching 2,362 ft, lies just north of the Golden Gate Bridge and provides access to the Marin Headlands. Originally built in the 1930s, it served as a connection between Fort Baker and Fort Barry. These military bases were vital components of the Bay Area’s World War I fortifications.

Owner

The National Park Service
Client

Federal Highway Administration
Project Completion Date

May 2017
Location

Sausalito, CA

Freyssinet USA - Tunneling Repair Project in California

Revitalizing the Baker-Barry Tunnel

The Baker-Barry Tunnel was originally designed for military vehicles and equipment, limiting its clearance to just 16.4 feet high and 19.7 feet wide. Today, it accommodates a single highway lane and cycling lanes, with traffic signals controlling vehicle flow at each end.

Over time, ongoing water seepage earned the tunnel the local nickname “the car wash,” raising safety concerns for drivers. Managed by the Federal Highway Administration on behalf of the National Park Service, the tunnel underwent a tender-phase assessment, resulting in a comprehensive repair plan. This project focused on sealing the leaky lining, upgrading tunnel lighting, and replacing outdated utilities to improve safety and functionality.

Adapting the Approach

At the time, renovating a tunnel was an unconventional project for Freyssinet, but our expertise in applying shotcrete earned us a place on the project. While shotcrete was proposed for the tunnel lining and was expected to be a major part of the work, further discussions between Freyssinet and the National Park Service led to a reassessment of this approach.

Since the shotcrete lining wasn’t meant to serve a structural purpose but rather to prevent water infiltration and enhance visibility—particularly for cyclists—we evaluated whether it was the most cost-effective solution. Given its limited application area, its benefits wouldn’t be fully realized, making it a potentially expensive choice.

Instead, Freyssinet proposed an alternative solution that preserved some of the tunnel’s historic features while still delivering the necessary environmental improvements.

18,000

Working Hours Without Incidents
2,362

Length of Tunnel (ft)

Baker-Barry Tunnel Freyssinet USA Project

Prioritizing Preservation and Performance

A strong understanding of the tunnel owner’s priorities was essential in finding the right balance between restoration and preservation while optimizing the design. To assess site suitability, mock-up tests were conducted using the selected product—a non-porous, polymer-based coating.

The replacement material offered easy maintenance and could be applied in a much thinner layer, minimizing the impact on the tunnel’s cross-section. Additionally, polyurethane grout was injected into cracks to seal them, preventing further water infiltration. Value-engineering also led to the development of a more cost-effective yet high-performing lighting system, ensuring efficiency and safety improvements.

Concrete Restoration

From parking garages to commercial and residential buildings, industrial facilities, bridges, marine structures, liquid storage tanks, and dams, Freyssinet offers cutting-edge technology to protect, repair, strengthen, and maintain the structures that keep your daily lives running smoothly.

Learn More

Tunnel Solutions

Tunnels are long-term investments, often exceeding their intended lifespan. Harsh conditions, especially water infiltration, accelerate deterioration. Freyssinet provides expert solutions to restore integrity and extend service life through advanced waterproofing and reinforcement.

Discover Our Solutions

Concrete Restoration

Learn More

Tunnel Solutions

Discover Our Solutions

Contact Freyssinet Today!

Thank you for your interest in Freyssinet, Inc. To discuss a specific project, sign up for our newsletter, schedule a presentation, or request other information, please fill out the form below and we will contact you shortly.