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101 Santa Clara Auxiliary Lanes Project Twitter


The Project

This project will add auxiliary lanes in both directions along US 101 from State Route 85 to Embarcadero Road in Santa Clara County. It complements a project in San Mateo County which will add auxiliary lanes on US 101 between Embarcadero Road and Marsh Road.

The Need

Traffic along the US-101 corridor between Marsh Road in San Mateo County and SR 85 in Santa Clara County is significantly congested, and this is expected to increase. The corridor serves as a major route to the employment centers in Silicon Valley as well as to the Mineta San Jose International airport.


The project will alleviate existing and projected congestion, and will upgrade the facility to meet safety and operational requirements.


The project is developed through a partnership among the Santa Clara Valley Transportation Authority (VTA), the Metropolitan Transportation Commission (MTC), and the California Department of Transportation (Caltrans). Project sponsors include local and state agencies.

Project Funding

The total project cost is roughly $72 million made up of $56 million from State’s Corridor Mobility Improvement Account (CMIA) Funds and $16 million from VTA Local Program Reserve Funds.

Project Schedule

Start Construction: Spring 2012
Project Completion: Summer 2014.


The US-101 Auxiliary Lane project will relieve traffic congestion and improve operations and traffic flow.