Construction from Whipple Avenue to Interstate 380 (I-380) to add a lane on U.S. 101 will begin in early February 2020 and last through summer of 2022. Plan ahead for delays and nightly lane closures.

Starting in February 2020, Caltrans will implement freeway lane closures Sunday-Thursday nights. In order to maximize construction efficiency, Caltrans will require lane closures Sunday through Thursday night at 9 p.m. instead of 10 p.m., which was the start time for the construction on the project south of Whipple Avenue. By allowing for more time each night, Caltrans estimates the project will be done six months earlier and at a savings of $40 million over a 10 p.m. start time. 

To reduce congestion during extended work hours and nighttime closures, Caltrans will implement a Smart Work Zone system, which uses electronic message signs to alert motorists of changing traffic conditions. The Smart Traffic System uses loops detectors embedded in the pavement to monitor traffic volumes and speeds downstream of the message signs set up in the construction zone. Traffic information will be posted on this side of the road message signs, informing motorists about upcoming slowdowns, incidents or other issues well before they are visible, providing drivers extra time to react to changing conditions. More information will be available as construction nears.

For questions during construction, contact the Caltrans Public Information Officer Alejandro Lopez at 510-286-4948 or 101express@dot.ca.gov.

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