Southgate Road on Treasure Island


The Southgate Road Relocation will relocate Southgate Road, the critical local connection between the I-80 westbound and eastbound on- and off-ramps, and reconstruct and reopen the I-80 eastbound off-ramp to Yerba Buena Island. 

This project is part of an 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 and the Office of Economic and Workforce Development on this effort. These upgrades will support the Treasure Island Transportation Program.

Project Map

An aerial view of the new road configuration

Timeline & Status 

Environmental clearance, final design, and right of way certification are complete. Construction contract advertisement is scheduled to start in 2019 and selection of a contractor is expected in January 2020. Construction completion is expected in 2021.  

Cost & Funding 

The Southgate Road Relocation project will cost $51,030,807. Funding comes from the Federal Highway Bridge Program, State Prop 1B, the Bay Area Toll Authority, and the Treasure Island Development Authority.


Eric Cordoba, Deputy Director for Capital Projects

Related programs

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.

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.

The West Side Bridges Retrofit will seismically retrofit eight existing bridge structures along Treasure Island Road to meet current seismic safety standards.

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