State Route 4 (Segments 1 and 3)

The significant growth occurring in East County will result in ever-increasing traffic demand on existing State Route 4 through the downtown areas of Oakley and Brentwood. Upgrading the existing highway would have resulted in expensive and disruptive acquisition of residential and commercial properties, and was therefore not feasible. As a result, the State Route 4 Bypass project was constructed to the west of the Oakley and Brentwood downtown areas. The purpose of the project is to provide necessary infrastructure to improve local circulation/mobility for Antioch, Oakley, and Brentwood and at the same time, relieve through-traffic congestion in Oakley and Brentwood.
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