Christies Beach Outfall project wins CCF Earth Award
14 July 2010
BMD Constructions collected a CCF Earth Award in South Australia in the $5-20m category at an awards evening held on Saturday 10th July.
The CCF Earth Awards have the specific aim of recognising outstanding work in construction and environmental excellence which reflects development and use of the best technologies and practices by Australian civil contractors.
Commissioned in the early 1970s, the Christies Beach Waste Water Treatment Plant (WWTP) receives and treats wastewater from surrounding communities and businesses. Located in Adelaide's southern suburbs, SA Water is upgrading the plant to increase capacity and meet the expected growth of the area.
Part of the overall WWTP upgrade, was the construction of a new outfall (Contract C04) to discharge excess treated effluent in line with new environmental protection guidelines. The new 1,200mm diameter outfall pipeline is partially buried on the sea floor and extends some 650m from the shore into the Gulf of St Vincent.
As Principal Contractor for the construction of the outfall works BMD Constructions engaged Smithbridge Australia (SBA) as a joint venture partner to develop and execute a pipe delivery methodology.
Reflecting best practice, the construction of the 600m offshore pipe was executed through a combination of innovative approaches including a pipe delivery methodology that involved launching on an inclined profile, a 180m temporary bridge, a sheet pile cofferdam installed through the beach crossing, and a shore-based winch pulling through an offshore anchor.
To make this happen the outfall pipe was fabricated onshore with a temporary jetty and adjacent cofferdam erected to allow trench excavation through the beach crossing using conventional excavation equipment. Offshore dredging was undertaken by cutter suction with the pipe launched into the trench, section by section through a continuous seven day operation.
Detailed planning saw the works executed with minimal deviation from the original planned approach. The team managed a number of unforeseen impacts to achieve outstanding environmental, construction and commercial targets. The $14.3m project commenced in February 2009 and was completed April 2010.
'BMD completed their contract on time and under the budget estimate, and to the requirements of the specification. The project team was particularly impressed with the temporary bridgeworks system and this told toward the success of this contract.'
Angelo Rossi, Snr Project Manager, SA Water
