Overview
An aerial view of the completed Southgate Road project on Yerba Buena Island. The west span of the Bay Bridge and San Francisco skyline stand in the background.

Introduction

The Yerba Buena Island / I-80 Southgate Road and Interchange Project reconstructed the I-80 eastbound off-ramp to Yerba Buena Island. The project features an innovative design that enhances safety and circulation.

This project is part of a larger effort to replace and retrofit key roads and on- and off-ramps that connect the I-80 (the highway on the Bay Bridge) and Yerba Buena Island.

The Transportation Authority is working jointly with the Treasure Island Development Authority on this effort. These upgrades will support the Treasure Island Transportation Program.

Project Recognition

In June 2024, the California Transportation Foundation awarded the Yerba Buena Island / I-80 Southgate Road and Interchange Project the Interchange the Project of the Year Award. For more information, here is the press release: Transportation Authority Southgate Road Project Wins Interchange Project of the Year.  

In November 2024, the American Council of Engineering Companies awarded the Yerba Buena Island I-80 / Southgate Road & Interchange Project an Honor Award in the California 2025 Engineering Excellence Awards competition. 

 

Timeline

  • June 2020

    Construction began

  • May 2023

    Construction ended

Opening Ceremony

A large group of people pose in front of the newly-completed Yerba Buena Island / I-80 Southgate Road and Interchange Project
VIPs cut the ribbon for the Yerba Buena Island / I-80 Southgate Road and Interchange Project
VIPs watch a speaker at the Yerba Buena Island / I-80 Southgate Road and Interchange Project ribbon-cutting ceremony.
A group of people, including SFCTA Executive Director Tilly Chang and State Senator Scott Wiener, stand in front of the newly-finished Yerba Buena Island / I-80 Southgate Road and Interchange Project.
A group of people, including SFCTA Executive Director Tilly Chang and SFCTA Deputy Director for Capital Projects Carl Holmes, stand in front of the newly-finished Yerba Buena Island / I-80 Southgate Road and Interchange Project.
A group of people, including SFCTA Executive Director Tilly Chang and SFCTA Deputy Director for Capital Projects Carl Holmes, stand in front of the newly-finished Yerba Buena Island / I-80 Southgate Road and Interchange Project.
A group of people, including SFCTA Executive Director Tilly Chang and SFCTA Deputy Director for Capital Projects Carl Holmes, stand in front of the newly-finished Yerba Buena Island / I-80 Southgate Road and Interchange Project.
A group of people, including SFCTA Executive Director Tilly Chang and SFCTA Deputy Director for Capital Projects Carl Holmes, stand in front of the newly-finished Yerba Buena Island / I-80 Southgate Road and Interchange Project.

Cost & Funding 

Funding for the $51.6 million project comes from the Federal Highway Bridge Program, State Proposition 1B facilitated by Caltrans, State Affordable Housing and Sustainable Communities Program, Bay Area Toll Authority, and the Treasure Island Development Authority.

Contact  

info@sfcta.org

Key features

Project Design

In collaboration with the Treasure Island Development Authority, the project features an innovative design that will improve traveler safety for motorists, cyclists, and pedestrians and enhance traffic circulation by:

  • Building the I-80 Bay Bridge eastbound off-ramp to seismic standards and connections to the Transportation Authority’s award-winning YBI East Side Ramps Project that provided westbound Bay Bridge access to the Islands in 2016;
  • Redesigning the YBI/I-80 Southgate Road circulation to separate vehicle traffic from bicycle and pedestrian paths and accommodating heavy duty vehicles and trucks; and
  • Creating dedicated bicycle and pedestrian facilities that connect East Bay travelers arriving to Yerba Buena Island Vista Point (from the Bay Bridge East Span Bike/Pedestrian path) to Treasure Island via Macalla Road.

The project is the second of three projects led by the Transportation Authority designed to replace and retrofit key roads and ramps linking the islands to I-80. The first project was the I-80 East Side Ramps project, completed in 2016. The I-80 Southgate Road Interchange Improvement Project completed in 2023 and the Transportation Authority lead the West Side Bridges Retrofit. 

Disadvantaged Business Enterprise goal: The construction firm for the project, Ghilotti Construction Company Inc., has committed to direct almost 17 percent of the budget to disadvantaged business enterprises. Work for DBE firms may include demolition, excavation, erosion control, noise monitoring, landscaping, traffic control, and trucking. 
 

Related programs

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Rendered image of an island with buildings and a port in the nearby lagoon. There is a ferry pulling up to a dock in the foreground.

Treasure Island Transportation Program

The Treasure Island Transportation Program will address the island's growing transportation needs with a goal to have at least 50 percent of trips made by transit instead of private vehicles.
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an aerial image of a freeway ramp existing the Bay Bridge

I-80 East Side Ramps Project

The new westbound I-80 on- and off-ramps that connect Yerba Buena Island and Treasure Island to the eastern span of the Bay Bridge are open.
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Rendering of the newWest Side Bridges, connecting Treasure Island Road to Hillcrest Road and the Bay Bridge

West Side Bridges Retrofit

The West Side Bridges Retrofit will seismically retrofit eight existing bridge structures along Treasure Island Road to meet current seismic safety standards.
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A view of the eastern span of the Bay Bridge from Vista Point

Vista Point on Yerba Buena Island

Vista Point is a scenic rest stop on Yerba Buena Island near the Bay Bridge east span bicycle/pedestrian path.