I-80 Gilman Interchange Improvement Project

I-80 Gilman Interchange Project map

Overview

Caltrans and the Alameda County Transportation Commission (Alameda CTC) in cooperation with the cities of Berkeley and Albany began construction in May 2021 on the Gilman Interchange Improvement Project at the Interstate 80 Gilman Street exit in Berkeley.

The project will enhance safety and improve traffic operations along Gilman Street between West Frontage Road and 5th Street through the I-80 Interchange. The main project components are two roundabouts at Gilman Street intersections on both sides of I-80, as well as a new bicycle/pedestrian overcrossing over I-80 and bicycle facilities at and near the interchange. The project will also close the gap in the Bay Trail at the west end of Gilman Street and create a dedicated two-way cycle track along Gilman Street from the interchange to Fourth Street.

Project Purpose

Simplify and improve navigation, mobility, and traffic operations on Gilman Street between the West Frontage Road and 5th Street through the I-80 interchange
Reduce congestion, vehicle queues, and traffic, bicycle, and pedestrian conflicts
Improve local and regional bicycle and pedestrian facilities through the I-80/Gilman Street interchange
Enhance safety for drivers, pedestrians, and bicyclists at I-80/Gilman Street interchange

The Gilman Street Interchange Project is being constructed in two separate construction contracts:

1. Gilman Street Pedestrian Overcrossing Project – Phase 1

Project Scope

Construct a bicycle/pedestrian overcrossing south of Gilman Street similar to the crossing over I-80 at University Avenue, began in May 2021. It will involve ramp closures on I-80, street closures and brief overnight closures of I-80 in one direction at a time. Work on this phase was concluded in 2023.

2. Gilman Street Roundabouts Project – Phase 2

Project Scope

The second phase, building a double roundabout, is scheduled to begin in July 2022 and complete in 2024, weather permitting. Periodic closures of Gilman Street, local streets and freeway ramps will be necessary to construct the project. Work on this phase is expected to conclude in 2024.