The existing State Route 160/Highway 4 Interchange currently includes only two of the four possible interchange movements: the eastbound Highway 4 to northbound SR 160 connector ramp and the southbound SR 160 to westbound Highway 4 connector ramp. The State Route 160/Highway 4 Connector Ramps project will construct two new connector ramps, one connecting westbound Highway 4 to northbound SR 160, and one connecting southbound SR 160 to eastbound Highway 4. The project also includes adding an additional 12-foot auxiliary lane to the outside of existing SR 160 in both directions from the SR 160/Highway 4 Interchange to the East 18th/Main Street Interchange, as well as building a soundwall extension and retaining walls. The project is proposed to be constructed within existing right-of-way and no utilities will be relocated. The southbound SR 160/Highway 4 separation structure will accommodate a future eBART extension in the median of Highway 4.
PROJECT ALLOCATED BUDGET
The project is funded entirely by $50 million in Bridge Toll Funds.
Final design is complete. The project has been advertised for construction. Construction is expected to begin in early 2014.
In order to respect the local environment, project partners have been working closely with the East Contra Costa County Habitat Conservancy to ensure compliance with the Habitat Conservation Plan (HCP) for the Highway 4/State Route 160 connector ramp project. The construction of these new connector ramps requires that approximately 75 shrubs and trees be removed. In order to meet the HCP requirements, which ensure that nesting season (February 15 – August 31 as outlined in the Migratory Bird Treaty Act) is not interfered with by any construction, tree removal will occur in advance of construction to ensure no nesting birds are impacted.
A nesting survey was conducted by the project biologist, and while the survey included all birds protected under state and federal regulations, specific targeted species were those species covered under the requirements of the HCP, including the Swainson’s Hawk, Golden Eagle and Western Burrowing Owl. No tree nests in the project area were found, and there was no sign of use by burrowing owls.
Tree removal work will begin Wednesday, September 18, 2013 now that biologists have confirmed there are no nests present in the trees scheduled for removal.