Inner City Bypass upgrade

Brisbane City Council is pleased to advise that works to upgrade the Inner City Bypass (ICB) are now complete.

The upgrade is one of more than 90 projects being delivered as part of Council’s commitment to invest more than $2 billion to tackle traffic congestion.

The upgrade has transformed Brisbane’s busiest arterial road under Council’s control, providing increased capacity on the ICB, improved travel times and safety for all road users, and improved connectivity to Legacy Way and the wider road network.

The ICB upgrade was an initiative of Brisbane City Council and was delivered by Transurban Queensland. Following the completion of the upgrade, Transurban Queensland has taken over operational support, routine maintenance and incident response services along the ICB.

Initial works started on the upgrade in late 2016 and construction was completed in August 2018.

Fly-through video

Watch the fly-through video below to find out more about the project. Alternatively, watch the video on Council's YouTube channel.

Read supporting information for this video.

About the project

The ICB is one of Brisbane's most important routes and is integral to the city's economic growth. It is a vital link in the road network with connections to Lutwyche Road, AirportlinkM7, Clem7, Legacy Way and the soon-to-be-upgraded Kingsford Smith Drive.

More than 105,000 vehicles use the ICB every weekday. Prior to the upgrade, the ICB was operating at up to 90% capacity and would have been severely over capacity by 2021 if the upgrade did not go ahead.

The upgrade involved:

  • widening the ICB westbound from three to four lanes between the westbound approach to the RNA tunnel and the Legacy Way portal
  • widening the ICB eastbound from three to four lanes between the Legacy Way portal and Herston Road exit
  • construction of a new westbound ramp to the ICB from Bowen Bridge Road for general traffic that also allows buses to connect directly to the ICB from the Inner Northern Busway
  • new bus priority measures at the Herston Road exit off the ICB, including a new dedicated bus priority lane
  • improvement works at the Herston Road roundabout.

The upgrade will also improve safety on the ICB by increasing capacity and reducing congestion-related accidents.

Project map

View the project plan in your preferred format:

Bus priority measures

The upgrade delivered a number of bus priority measures to improve public transport options and travel times, making it easier for people travelling to and from the western suburbs.

New and improved ICB entry and exit points will reduce travel time for buses and provide opportunities for new bus services to and from the western suburbs using Legacy Way.

The construction of a westbound ramp from Bowen Bridge Road and the Inner Northern Busway onto the ICB will allow bus services to use the Legacy Way tunnel in both directions.

A number of inbound bus services have already been re-routed to take advantage of Legacy Way.

Since the tunnel opened in 2015, bus users have experienced average journey time savings of up to 13 minutes and patronage has also increased by 52% on inbound bus services.

The new westbound on-ramp will provide travel time savings of around 10 minutes for buses heading towards the western suburbs, allowing buses to interchange with the Inner Northern Busway and the planned Brisbane Metro.

Herston Road roundabout - improvement works and benefits

As part of the ICB upgrade, improvement works have been carried out on the Herston Road roundabout (intersection of Bowen Bridge Road, Gilchrist Avenue, the ICB off-ramp and Herston Road) to improve traffic flow around the roundabout and at the ICB Herston Road exit.

Works included installing new traffic lights and signalised pedestrian crossings at:

  • the ICB exit onto the roundabout (at the intersection with Gilchrist Avenue)
  • the roundabout exit onto Herston Road.

New traffic signals have also been installed for vehicles entering the roundabout onto Gilchrist Avenue from Bowen Bridge Road and the Cornerstone carpark (just short of the intersection with the ICB off-ramp).

Sections of the roundabout, Gilchrist Avenue and Herston Road have also been re-paved.

With these improvement works now complete, queue lengths on the ICB eastbound, prior to the Herston Road exit, are expected to be reduced by more than 50%.

Project status 

Initial works on the upgrade began in December 2016. Major construction activities started in early 2017, with the upgrade completed in August 2018.

Project benefits

The ICB upgrade will increase capacity and accommodate future growth along this key corridor.

The upgrade will:

  • improve travel times
  • reduce traffic congestion
  • improve public transport facilities
  • improve safety for all road users
  • improve connectivity to Legacy Way and the wider road network.

Transurban Queensland

Transurban Queensland approached Council in late 2015 with an innovative proposal to deliver the ICB upgrade and provide ongoing incident response, routine maintenance and operational support. This proposal was then assessed under Council's Innovative Proposals Policy.

In March 2017, Council reached an agreement with Transurban Queensland to help fund and deliver the ICB upgrade and to take over responsibility for the ongoing maintenance and operations of the ICB. As part of this agreement, Transurban Queensland will manage the routine maintenance for the ICB and provide ongoing operational and incident response support on the ICB and its surrounding road network.

Transurban currently operates Legacy Way, Clem7, Go Between Bridge and AirportlinkM7. The company's experience in maintaining and operating the road network surrounding the ICB means it is uniquely positioned to assist Council in responding to incidents to help improve traffic flow and safety outcomes on the ICB.

Transurban Queensland's proposal provides benefits to both ICB users and Brisbane's broader traffic network, represents value for money for Brisbane's rate payers and will generate significant savings to Council.

Council's assessment report of Transurban Queensland's Innovative Proposal provides more information on this agreement.

Read the report:

More information

For more information about the design and construction of the ICB upgrade:

  • phone Council on 07 3403 8888
  • email the project team
  • write to the project team:
    Inner City Bypass upgrade project
    Brisbane City Council
    GPO Box 1434
    Brisbane Qld 4001.
Last updated:7 May 2019
Topics: herston road