State Route 239 Project

Online Open House


DECEMBER 17, 2021- FEBRUARY 4, 2022

Welcome to the State Route 239 environmental scoping open house. The purpose of environmental scoping is to identify the environmental topics that the project team should study to assess the potential environmental impacts of a construction project. Public input on this project will be critical for ensuring the SR 239 project team’s studies are comprehensive and thorough. Within this website you will be able to review informational materials about this phase of our work. Please use the online comment form provided above on the COMMENTS tab (or click the SUBMIT COMMENT button below) to send your thoughts and questions to the project team.

The proposed State Route 239 Project would provide a new, four-lane highway from State Route 4 at Marsh Creek Road in Contra Costa County to Interstate 580 in Alameda County or Interstate 205 in San Joaquin County. This new state route would ultimately improve the transportation network for an area that has few viable north-south roadway connections in this approximately 17-mile stretch between eastern Contra Costa and the Central Valley.

On January 20, 2022, please visit this page for a link to our interactive virtual scoping meeting that will start at 5:30 p.m. Visitors will be permitted to join the meeting 15 minutes before the start time. The team will make a presentation about this project and a panel of experts will be available to answer your questions about State Route 239. We look forward to hearing from you!

For language translation or accessibility needs, please do not hesitate to reach out to our project team at (925) 390-3794 or