I-80/Gilman Interchange Project

The Interstate 80/Gilman Street Interchange project, located in northwest Berkeley near its boundary with the City of Albany, will reconfigure the Interstate 80/Gilman Street interchange. The purpose of the project is to improve navigation and traffic operations on Gilman Street between West Frontage Road and 2nd Street through the I-80 interchange so that congestion is reduced, queues are shortened and merging and turn conflicts are minimized.

In addition to improving mobility through the Gilman street corridor, the project aims to close the gap in local and regional bicycle facilities through the I-80/Gilman Street interchange and provide access for bicycles and pedestrians traveling between the Bay Trail and North Berkeley.

This project is being constructed in two phases:

  • PHASE 1: Pedestrian and Bicycle Overcrossing
  • PHASE 2: Interchange Improvements and Local Street Improvements; pedestrian and bicycle improvements through the interchange; Bay Trail gap closure; safety improvements at the Gilman/Union Pacific Railroad at grade crossing

On May 20, 2021, Alameda CTC and the California Department of Transportation jointly held a virtual groundbreaking celebration to commemorate the start of construction on the project.

Phase 1 was completed in 2023; Phase 2 is scheduled for completion in 2024.

For closures and traffic related information during construction, visit Caltrans’ website:
Project Fact Sheet

Roundabouts Video Simulation

This video simulates the path of a vehicle from the southbound I-80 Gilman Street off-ramp to Gilman and 2nd Streets in Berkeley. The existing stables and light poles of Golden Gate Fields are visible to the west, as the vehicle enters the proposed western roundabout. That roundabout re-directs the vehicle eastward onto Gilman Street, beneath I-80 to the second roundabout. As the vehicle heads further east on Gilman to 2nd Street, the green striping of the proposed two-way cycle track becomes visible.

The I-80 Gilman project is funded by Measure BB in addition to Federal and State funding sources. The total project cost is estimated at $43.37 million.

The project is currently in the environmental phase. Final project approval is anticipated in spring 2019. Construction is anticipated to begin in 2020 and conclude in 2023.

At-grade Path Through I-80 Gilman Interchange Video Simulation

This video simulates the at-grade path of a pedestrian or bicyclist from Gilman and 2nd Streets through the I-80 Gilman Interchange to Tom Bates Regional Sports Complex (TBRSC). The traveler begins on the two-way cycletrack on Gilman Street and crosses 2nd Street, where the cycletrack transitions to a shared-use path. The traveler then crosses Eastshore Highway and the eastbound I-80 exit ramp before crossing beneath I-80, where there is fencing along the shared-use path. As the traveler continues west, the western roundabout and TBRSC come into view. The traveler then crosses the westbound I-80 entrance ramp and West Frontage Road to arrive at the playing fields and SF Bay Trail.

Southern Cycletrack Pedestrian/Bicycle Overcrossing Option Video Simulation

This video simulates the path of a bicyclist beginning at Gilman and 4th Streets along the two-way cycletrack on the south side of Gilman Street, continuing onto the Pedestrian/Bicycle Overcrossing (POC) crossing over I-80 south of Gilman Street and ending at Tom Bates Regional Sports Complex (TBRSC). As the westbound bicyclist approaches the railroad crossing, the striped buffer zone and parking between the cycletrack and vehicle travel lane are in view to the right. The bicyclist then crosses 2nd Street and travels along the shared-use path until crossing Eastshore Highway and turning south to ascend the eastern approach of the POC. As the bicyclist reaches the top of the POC and turns to the west, views of the San Francisco Bay and Golden Gate Bridge can be seen, before the bicyclist descends the western approach of the POC which terminates between TBRSC and the San Francisco Bay Trail.

A pre-bid meeting was held on August 30, 2021. Below is a recording of the meeting and meeting materials.
Alameda CTC and the California Department of Transportation jointly sponsored virtual groundbreaking celebration a virtual groundbreaking celebration to commemorate the start of construction on the project.

Media Coverage

PRINT: Berkeleyside
KPIX-TV interview with Alameda CTC’s Executive Director, Tess Lengyel

A pre-construction outreach meeting was held on May 20, 2020. See the links below for a recording of the meeting and meeting materials.
An open forum hearing was held on January 15, 2019 at James Kenney Recreation Center Community Room in Berkeley, CA. See links to the open forum hearing documents below.
A public information meeting was held on February 7, 2018 at Albany City Hall. See links to the public information meeting documents below.
The public was invited to attend an open house to learn about the project on April 27, 2016 at the North Berkeley Senior Center. See links to the open house documents below.

Project Documents

Frequently Asked Questions

The Gilman Street interchange on I-80 is a complex system of roadways at the boundary of Berkeley and Albany. It provides access to regional recreational facilities and popular businesses in both cities, including Golden Gate Fields and Target. The interchange has higher-than-average rates of vehicular injury and fatality collisions, including above average accident rates on several ramps. The interchange is identified as a "high stress" environment for cyclists by the City of Berkeley.

Roundabouts are proven to reduce serious accidents while providing increased capacity and improved traffic operations, as compared to a traffic signal with the same number of lanes. According to the Federal Highway Administration, installing a roundabout typically results in a 90% reduction in fatality accidents.1 Roundabouts also provide environmental benefits, as vehicles typically do not need to stop and idle. Roundabouts improve operations and traffic flow and provide opportunities for landscaping and beautification within constrained space.

The project is designed to improve safety for all modes of transportation. In addition to the roundabouts, it includes a pedestrian and bicycle overcrossing over I-80 that will tie into new Gilman Street sidewalks and the existing Bay Trail; an at-grade pedestrian and bicycle path through the interchange; and a two-way cycle track on Gilman Street that will flow from the pedestrian and bicycle overcrossing to a new signal at 4th Street. Finally, the project will include new bicycle "sharrows" connecting Gilman Street to Cordonices Creek, across Gilman Street. The roundabouts and pedestrian elements would be fully landscaped.

Yes. The viability of traffic signals was studied over the course of 5 technical reports prepared from 1998 to 2014. All concluded that given the volume of traffic at the interchange and the number of intersecting roadways, an acceptable level of service could not be achieved with traffic signals.

No. The pedestrian crossing at a roundabout is reduced to two simple crossings of one-way traffic moving at slow speeds. Pedestrians at a traffic signal crossing need to contend with vehicles turning right or left on green, vehicles turning right on red, and vehicles running the red light. The latter two often occur at high speeds, increasing the chance of injuries or fatalities to pedestrians. The design of the current roundabouts includes a new pedestrian/bicycle shared use path and dedicated pedestrian connections.

Cyclists have a legal right to ride on most roadways with motorized traffic. Roundabouts are like other intersections in that cyclists may either follow the rules of the road and maintain travel on the roadway, or use available paths and crosswalks to safely bypass the roundabout. Cyclists who choose to use the roundabout should always ride in the center of the lane. The current roundabout project includes a bike-only exit.

Yes. The current design of the roundabouts will change access to and from Eastshore Highway.

The project would remove direct access to northbound Eastshore Highway from Gilman Street. Drivers on westbound Gilman and those exiting properties between Gilman and Harrison Streets (including Red-D-Arc and PS Public Storage) would take 2nd Street northbound one block to Harrison Street. A left turn on Harrison Street would then provide access to northbound Eastshore Highway.

Access to southbound Eastshore Highway from eastbound Gilman Street or I-80 would also change. Drivers would be routed via the eastern roundabout to Gilman and 2nd Streets, and would then turn right (south) onto 2nd Street. A right turn on Page Street would then lead to southbound Eastshore Highway.

Parking would be converted from perpendicular to parallel on Harrison Street between Fourth and Fifth Streets, and there would be some loss of parking at the western end of Gilman Street, resulting from the extension of the Bay Trail. There would be temporary parking impacts during construction at Tom Bates Regional Sports Complex. Otherwise, parking would remain unchanged in the rest of the project area.

Yes. The Gilman interchange is designed to accommodate all categories of California legal tractor-semitrailers: "Black" CA legal 65 FT trucks, "Green" STAA-56 FT trucks, and WB-67D double-bottom combination trucks.

From March, 2016 to February, 2018 the project team held a series of informational meetings, each targeting either public agencies, community organizations, area-wide or specific business owners, or the interested public. Feedback was solicited at each and incorporated as feasible into the project. The team has led ongoing meetings and coordination with the cities of Albany and Berkeley, as well as large and directly affected businesses such as Golden Gate Fields, Pacific Steel, Red-DArc, and Target. Individual property owners in the project area have been identified and contacted about project meetings. The January 15, 2019 Open Forum Hearing will be followed by future public information events. Project updates are available at https://www.alamedactc.org/i80gilman, and questions/comments can be sent to inquiry@i80Gilman.com.

The roundabouts are expected to be completed in late 2022/early 2023. Public release of the draft environmental document is a milestone in project development. Environmental certification is expected to occur in Summer 2019. Following certification, project designs will be refined into construction documents based on further input from elected officials and the public. Construction is expected to begin in late 2019 or early 2020.

The California Department of Transportation (Caltrans) is the Federal and State lead agency for environmental compliance. The Alameda County Transportation Commission (Alameda CTC) is the implementing agency, and is working cooperatively with the cities of Berkeley and Albany to deliver the project. The primary funding sources of the project are State funds and Measure BB, the 2014 voter-approved extension of the transportation sales tax.