I-80 at Gilman Roundabouts

KAI is preparing a Project Study Report (PSR) and Project Report for ramp intersection improvements at the I-80/Gilman Street interchange in Berkeley. The PSR includes five alternatives for analysis including two separate alternatives that convert the existing tight-diamond ramp intersections to multi-lane roundabouts. The lead agency for the project is the ACTC, with the city of Berkeley and Caltrans as key stakeholders.

Key issues associated with the project include incorporating frontage roads as fifth and sixth legs of the roundabouts, the nearby Union Pacific Railroad (UPRR) at-grade crossing, multimodal access, minimizing ROW takes of fully developed parcels, incorporating ramp metering, and high-occupancy vehicle (HOV) by-pass lanes. KAI's approach to this project was to provide an engineering solution that improves congestion and safety but also meets the needs of the community. Some of the challenges in achieving this goal is to improve local access for business, create a quality experience for all modes, maintain all traffic movements during construction, and provide a ‘gateway’ to Berkeley.