Interstate 680 Auxiliary Lanes / Diablo to Sycamore Valley - Crow Canyon to Bollinger Canyon (Segments 1&3)

This project constructed auxiliary lanes in the I-680 corridor from Bollinger Canyon Road to Crow Canyon Road in San Ramon and from Sycamore Valley Road to Diablo Road in Danville. These improvements included an additional 12-foot lane and 12-foot wide shoulder between interchanges in the northbound and southbound directions, retaining walls, new soundwalls, and replacement planting in the corridor. Structure widening was required at Laurel Drive between Sycamore Valley Road and Diablo Road.

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