Single Tracking Alert: Late night work on the Yellow Line in Contra Costa County to support BART’s Digital Railway (next work dates: October 27-30)

Service will be reduced from two tracks to one at various locations along the Yellow Line in Contra Costa County over the next few months so new fiber optic cable can be installed as part of the effort to modernize BART’s technology infrastructure. BART is using the dedicated fiber to strengthen and modernize its communications network, adding critical redundancy and additional pathways for network traffic. The expanded fiber infrastructure will improve the resilience of technology systems supporting BART’s operations and help provide greater protection against network disruptions.

The work will start just before midnight and continue overnight until it concludes before the normal start of BART service the next morning. Starting at midnight, riders should expect delays of 10-15 minutes. This work may cause a minor delay to the final train transfers of the evening, but all riders will be able to reach their final destination. The Grand Meet at MacArthur and the final transfer to the Antioch DMU train will be coordinated. 

Work for this project will happen between Pleasant Hill and Concord stations on the following dates:

*October 27-30
*November 2-6
*November 9-11
*November 17-18

This article will be updated as more work dates are confirmed.

(this article was originally published in September 2026)