Eric Young, SFCTA

415-522-4816 office, 415-306-4509 cell,

The San Francisco County Transportation Authority today announced the start of construction on the Southgate Road Realignment project, which will provide safer connections at the I-80 Bay Bridge interchange at the top of Yerba Buena Island leading to and from Treasure Island. 

In collaboration with the Treasure Island Development Authority, the $63.7 million project features an intricate design that will improve traveler safety for motorists, cyclists and pedestrians and enhance traffic circulation by:

  • Relocating and re-designing Southgate Road and interchange, separating vehicle traffic heading to westbound and eastbound I-80/Bay Bridge lanes; 
  • Continuing the dedicated bicycle and pedestrian path from the Yerba Buena Island Vista Point (at the western terminus of the Bay Bridge East Span Bike/Pedestrian path) to Treasure Island via Macalla Road;  
  • Reconstructing and reopening the I-80 eastbound off-ramp to Yerba Buena Island from I-80 with a design that optimizes traffic flow; and 
  • Ensuring that all truck turning movements are accommodated in the area.
Rendering of Southgate Road Realignment Project

Rendering of Southgate Road Realignment Project final design

Funding for the project comes from the Federal Highway Bridge Program and State Prop. 1B facilitated by Caltrans, with local matching funds provided by the Bay Area Toll Authority, and the Treasure Island Development Authority.

“This innovative interchange design will support improved safety and movement for the thousands of residents and visitors of Treasure Island and Yerba Buena Island now and in the coming years,” said Transportation Authority Board Member Matt Haney (District 6), who also serves as Chair of the Treasure Island Mobility Management Agency.

“The Transportation Authority is excited to reach this milestone,” said Tilly Chang, Executive Director of the Transportation Authority. “We thank our funding and implementation partners for helping us to find a design solution at this challenging site, and to gather the resources to build this project in time to support the coming first phases of development on the islands.”

“I applaud the work that the Transportation Authority is leading,” said V. Fei Tsen, President of the Treasure Island Development Authority Board of Directors. “I’m excited that Treasure Island and Yerba Buena Island will continue to add infrastructure supporting sustainable development and more cycling and walking on the islands.”

The construction project is scheduled for completion in 2022. The contractor for the project, Ghilotti Construction Company Inc., has committed to direct almost 17 percent of the budget to disadvantaged business enterprises. It is anticipated that DBE firms may include demolition, excavation, erosion control, noise monitoring, landscaping, traffic control, and trucking. 

The Southgate 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. After the Southgate project, the Transportation Authority will lead the West Side Bridges Retrofit, anticipated to start construction in 2021.

Group photo of Southgate Road project team

Groundbreaking ceremony for Southgate Road Realignment Project.

From left to right: Linda Fadeke Richardson (TIDA Board of Directors), Thomas Fresquez (MSN Engineers), V. Fei Tsen (President TIDA Board of Directors), Bob Beck (TIDA Executive Director), Tilly Chang (SFCTA Executive Director), Eric Cordoba (SFCTA Capital Projects Deputy Director), Tony Tavares (Director Caltrans District 4), Dale Dennis (PDM Group), Yana Waldman (SFCTA Assistant Deputy Director Capital Projects), Greg Ressio (United States Coast Guard, Retired), Sid Osgood (US Coast Guard Captain, United States Coast Guard)

About the San Francisco County Transportation Authority (

The San Francisco County Transportation Authority’s mission is to make travel safer, healthier, and easier for all. We plan, fund, and deliver local and regional projects to improve travel choices for residents, commuters, and visitors throughout the city. The Transportation Authority Board consists of the 11 members of the San Francisco Board of Supervisors, who act as Transportation Authority Commissioners. Commissioner Aaron Peskin is Chair of the Board. Tilly Chang is the Transportation Authority’s Executive Director.