The Alameda County Transportation Commission (Alameda CTC), in cooperation with the California Department of Transportation (Caltrans) and the Federal Highway Administration (FHWA), environmentally cleared the construction of a high occupancy vehicle (HOV)/ express lane on northbound Interstate 680 (I-680) from the State Route 237 (SR-237) interchange in Santa Clara County to north of the State Route 84 (SR-84) interchange in Alameda County. The project was split into two phases to expedite the delivery. Phase 1 broke ground in April 2018. Phase 1 (From State Route 262 (SR-262) to SR-84.)

• Widen the freeway to accommodate the HOV/express lane together with several auxiliary lanes to facilitate the smooth and safe transition of traffic between local streets and the freeway between interchanges.
• Add a new 9-mile HOV/express lane and associated improvements between Auto Mall Parkway and SR-84, providing congestion relief in the corridor.
• Upgrade the I-680 Southbound Express Lane access configuration from controlled access to a near continuous access configuration.
• Modify bridge crossings.
• Construct retaining walls to accommodate the widening.
• Repave the full project limits.
Phase 2 (Will widen from SR-262 to the County line.)
• Construct HOV/high occupancy toll lanes in the northbound direction on I-680 from the county line south of SR-262.
• Construct nearly five miles of HOV/express lane along the I-680 corridor through widening, along with other necessary improvements, including structure widening/modification and retaining walls.

For total project cost and phase information, see the project Fact Sheets tab.