Interstate 680 Transit Investment and Congestion Relief Options Study

The I-680 Transit Investment and Congestion Relief Options Study was initiated in April 2015 and finalized in December 2015. The primary purpose of the Study was to define and evaluate potential transportation investment options that could reduce traffic congestion and encourage transit ridership on the I-680 corridor in the general area from the Benicia-Martinez Bridge to State Route-84 with a focus on potential transit service improvement options between Walnut Creek and Dublin.

The study evaluated five possible options, including:

  1. BART
  2. Light Rail Transit
  3. Ultra Light Rail Transit
  4. Bus Transit
  5. Connected Vehicle/Autonomous Vehicle (CV/AV) Support


Following an evaluation of each option, the study identified the most feasible and financially viable project as a combination of enhanced express and local bus service, connected vehicle and automated vehicle support in the corridor, and active traffic management. This includes new park and ride lots in the corridor, known as Smart Mobility Hubs, and use of the shoulders of I-680 for bus operations. Links to the executive summary and full study are found below.

I-680 Transit Investment and Congestion Relief
I-680 Study – Executive Summary