The Interstate 80/Gilman Interchange Improvement Project will improve navigation and traffic operations on Gilman Street between the West Frontage Road and 4th Street. In addition to improving mobility through the Gilman Street corridor, the project proposes to provide access for bicycles and pedestrians traveling between North Berkeley and the Bay Trail located on the west side of Interstate 80 by means of a pedestrian bridge over the freeway.

The proposed Gilman Street Bicycle/Pedestrian Overcrossing will cross Interstate 80 about 800 feet south of Gilman Street. The west approach to the bridge will begin about 150 feet south of Gilman Street and run parallel to and just west of the Bay Trail. The east approach will begin about 150 feet south of Gilman Street and be sandwiched between the Eastbound Off Ramp and Eastshore Highway. The City of Berkeley has indicated that they prefer a similar tied-arch bridge for the Gilman POC. This second arch bridge would echo the first and provide a consistent structural theme.

The proposed bridge type is a basket handle arch consisting of steel arch ribs with vertical hangers supporting a concrete deck girder. The main span across the freeway will be about 234 feet. The approach spans will vary in length from 81 feet to 115 feet. The length of each approach will be about 400 feet. The total structure length will be 1,062 feet.

Parsons is the prime consultant for the entire interchange improvement project and engaged OPAC to perform the following tasks:

• Developed bridge concepts.
• Prepared an Advanced Planning Study Design Memorandum.
• Review preliminary design.
• Independent check of the final design.