Bridges

The original Fitzroy River Bridge was a 177 metre long, one-lane bridge that carried the Great Northern Highway over the Fitzroy River in the town of Fitzroy Crossing in the Kimberley region of Western Australia. It was damaged beyond repair by the floods caused by Ex-Tropical Cyclone Ellie in January 2023. This resulted in the closure of the Great Northern Highway, splitting the town of Fitzroy Crossing in half and severing the critical freight link between Perth and the East Kimberley and the Northern Territory.

The New Fitzroy River Bridge is a two-lane, 270 metre long, 8 span, incrementally launched, continuous weathering steel/concrete bridge. It is the longest weathering steel road bridge in Australia and the first weathering steel road bridge constructed for Main Roads WA. It is taller, wider, and nearly 100 metres longer than the original bridge offering improved safety and flood resistance, improving the serviceability and resilience of the Great Northern Highway transport link. In order to replace the bridge as quickly and efficiently as possible, the Fitzroy Bridge Alliance was established by Main Roads WA. The Fitzroy Bridge Alliance designed, procured, and constructed the new Fitzroy River Bridge in under a year. The bridge was opened more than six months ahead of schedule and crucially before the start of the 2023/2024 wet season.

Designing and constructing the New Fitzroy River Bridge, in the remote north-east of Western Australia was a logistical challenge that demanded innovation, collaboration and a willingness to move away from the standard bridge design and construction processes. This paper discusses how the New Fitzroy River Bridge was designed, procured, and constructed in under a year. It will focus on the key challenges faced during the project, the critical design decisions made and the construction methodologies used to successfully deliver the project.