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11/13/13 - U.S. Route 101/Old Redwood Highway Interchange Improvement Project


On Tuesday morning, February 25, 2014, Caltrans plans to shift traffic at the Petaluma Boulevard North/Redwood Highway North Interchange. The northbound and southbound diagonal on-ramps to U.S. 101 will be closed for approximately four to six months while new on-ramps are constructed. During this construction period, motorists will access northbound and southbound U.S. 101 by using the loop on-ramps. Please expect delays and allow additional time to access U.S. 101 at this interchange.

Caltrans, the Metropolitan Transportation Commission, the Sonoma County Transportation Authority, and the City of Petaluma are working together on a project to upgrade the Old Redwood Highway Interchange on U.S. Route 101 in Petaluma. The new interchange will feature a new overpass with four traffic lanes, one bicycle lane in each direction, and ADA-compliant pedestrian paths in each direction. The new interchange will also come with new on and off ramps, each with two lanes. The highway will be widened to accommodate standard shoulders. And sound walls will be built next to existing sound walls along the southbound highway.

The project will help ease existing and projected congestion along the busy Route 101 corridor, and along the nearby surface streets. It will also reduce travel times, improve traffic flow and safety, and provide bicyclists and pedestrians will a quick and safe route from one side of Petaluma to the other.

Caltrans and its partners held a groundbreaking ceremony for the project on April 25, 2013. The project is expected to finish in the summer of 2015.