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California’s First Diverging Diamond Interchange Opens to Public Two Months Ahead of Schedule

SR 120/Union Road DDI alleviates traffic congestion and improves safety.

DDI

Dewberry | Drake Haglan, a privately held professional services firm, has announced that the State Route (SR) 120/Union Road diverging diamond interchange (DDI) in Manteca, California, is now open to the public.

California’s first DDI converts an aged, tight-diamond interchange to an upgraded interchange that carries travelers more efficiently on and off the freeway and to destinations north and south along Union Road. The
$25-million project includes new signalized intersections, highway lighting ramp metering, signs and striping, as well as a Class I pedestrian trail to carry pedestrians and bicyclists safely across the SR 120 freeway fully separated from traffic.

“We’re very excited that this critical intersection is now open to the public,” says Dewberry | Drake Haglan Construction Manager and Resident Engineer Rob Shackelford, PE, CCM. “Offering a safer intersection for motorists, pedestrians, and bicyclists ahead of schedule is something that our entire team is proud of.”

Dewberry | Drake Haglan provided construction management services, as well as environmental monitoring and public outreach on the project from its office in Manteca.

To learn more about the project and driving through the DDI, visit the project website.

The $25-million project improves safety and alleviates traffic congestion in Manteca, California. Photo courtesy of Dewberry.
The $25-million project improves safety and alleviates traffic congestion in Manteca, California. Photo courtesy of Dewberry.

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