The Department for Transport, Energy & Infrastructure of South Australia (DTEI) awarded McConnell Dowell an Early Contractor Involvement (ECI) contract for the replacement of the dilapidated Bakewell Bridge with an underpass in Adelaide, South Australia. Used by 25,000 cars per day, the 80 year old bridge formed a vital arterial into Adelaide's CBD.
Working with DTEI on South Australia's first ECI project, the team developed and assessed a number of configurations to find a solution that best balanced community, technical and cost parameters. The selected option includes two traffic lanes in each direction separated by a median; on-road bicycle lanes on each side of the road; and a wide shared-use path on the southern side for pedestrians, people with a disability and recreational cyclists. Two bridges span the underpass carrying road and rail traffic, and also cater for pedestrians and cyclists.
The major challenge for the project team was to build the underpass while continuing to allow trains to operate virtually uninterrupted. To achieve this, MacDow's engineers developed an "offline" construction method. The 3,000 tonne railway bridge was built alongside the rail tracks and slid into place over a weekend. This method avoided many months of significant construction disruption and delays for rail commuters.
The MacDow team developed over 150 different traffic management plans to ensure continuous flow of vehicles throughout the area. In addition, relocation of a large sewer, stormwater, gas, portable water lines, and Telstra cables was managed without interruption to any service.
Extensive consultation with the local community was undertaken to ensure all concerns were addressed. 22,000 households and businesses were advised of the works and kept informed throughout construction.
The project was delivered on time, on budget and has received a number of industry awards including the Civil Contractors' Federation Earth Award for Construction Excellence (National and SA), and SA Engineers' Excellence Award for 2008.
