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101 Auxiliary Lane Project University to Marsh

This Project Has Been Completed

101 Auxiliary Project Map Advisory/Updates Photos

The Project
This project will add auxiliary lanes in each direction on US 101, from the Marsh Road interchange to the University Avenue interchange in San Mateo County. The project will also modify the on-ramps to the three interchanges, and reconstruct the Ringwood Avenue Pedestrian overcrossing. The project complements two adjacent auxiliary lane projects on US 101, one from the University Avenue interchange to the Embarcadero Road Interchange and one which will add auxiliary lanes on US 101 between Embarcadero Road and State Route 85 in Santa Clara County.

The Need
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. In addition, collision rates along this corridor are substantially higher than the statewide average. In San Mateo County, the project is one of the last in a series of freeway widening projects on US 101, south of the San Francisco International Airport.

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


City of Menlo Park - Ringwood Pedestrian/Bicycle Overcrossing Project Page

This project is developed through a partnership among the City/County Association of Governments of San Mateo County (C/CAG), the San Mateo County Transportation Authority (SMCTA), the Metropolitan Transportation Commission (MTC), and the California Department of Transportation (Caltrans). Project sponsors include local and state agencies.

Project Status
PAED approved 10/1/08(A). Project was awarded on June 1, 2011 and construction started on July 10, 2011.

Project Costs
The current construction cost estimate bid by Granite Construction is $17.5M (including supplemental work and state furnished materials).

Project Schedule
Start Construction: July 10, 2011
Finish Construction: July 2012
End Contract (including plant establishment): July 2013

The US-101 Auxiliary Lane project will correct existing system deficiencies, relieve traffic congestion, and improve safety.