Innovative Consortium leads the way
Source: Abigroup - www.abigroup.com.au
24 May 2010
Building one of the world’s largest desalination plants would be a challenge for any contractor, but with Australia’s driest state in desperate need of a sustainable water supply, a tight timeframe increased the complexity of the equation.
Yet AdelaideAqua - a multi-national consortium of companies comprising Abigroup, McConnell Dowell Constructors, ACCIONA Agua, and United Utilities Australia – are well on track to deliver quality drinking water to Adelaide by the end of December 2010, and are providing some innovations along the way.
Abigroup and McConnell Dowell are in joint venture with ACCIONA Agua to design and build the $1.4 billion plant.
Abigroup and McConnell Dowell also lead an integrated alliance partnership with South Australian company Built Environs, to deliver the plant’s buildings and storage tanks.
World leaders in desalination, ACCIONA Agua, will team with United Utilities Australia to deliver the plant’s operational objectives until 2032, using unique and highly efficient dual-pass reverse osmosis technology.
With a year shaved off the original timeframe, AdelaideAqua faced a challenge to rapidly resource South Australia’s largest ever infrastructure project.
With a burgeoning workforce and accelerated timeframe, safety is of paramount importance on the 12 hectare site (with a current workforce of 1100, employee numbers are expected to peak around 1300).
“The Project Management Team lead the safety focus,” said Safety Supervisor Keith Rolls.
“Leadership is active and visible on site every day. Safety is not an add-on, it is an integral part of how safe construction is done here.”
Operating within a sensitive marine and coastal environment at Port Stanvac on Gulf St Vincent south of Adelaide, it was imperative that the project’s marine works be undertaken in an environmentally sensitive way.
AdelaideAqua’s bid was successful largely due to their commitment to safeguard the protected cliffs and near shore reef zone - choosing tunnelling to create the intake and outfall structures, rather than placing pipes on the seabed.
Dredging and pile driving activity for the intake and outfall risers was subject to compliance with the Environmental Protection Agency’s (EPA) water quality and dredging guidelines.
A determination to exceed the expectations of the client and the local community has led to a world-first innovation, which may have a number of future applications.
Project engineer Dr Kyleigh Victory was part of the team who designed a floating detention and sedimentation basin on dumb barge the Mandiri.
“The challenge was to set our water quality triggers well below those in the EPA criteria to safeguard against license breaches,” Dr Victory says.
Dredged material is taken onto the barge into sediment tanks where the solids settle through baffles, before feeding into a secondary treatment system of filter units and flocculent dosing.
The clean water is returned to the marine environment while the spoil is recycled as clean fill.
“Nobody else has ever gone to this extent to ensure compliance with water quality standards on a project of this nature,” Dr Victory says.
“Our motivation was community concern about the marine environment.”
Many of the project initiatives have been driven by the AdelaideAqua’s commitment to the local communities of Hallett Cove and the south coast.
Stakeholder Liaison Manager Bernie Auricht leads a team consulting with stakeholders including two local councils, coastal care groups, the local indigenous community, residents, local business owners, and schools.
“AdelaideAqua want to leave a legacy to the communities that we have worked in and alongside,” Ms Auricht says.
“Our approach to stakeholder consultation is very similar to that of our client SA Water – we are guests in the community and want to behave in a responsible and approachable way.”
Residents and business owners are regularly engaged through door knocking, and correspondence including electronic project updates, and each month a local charity is the recipient of a workplace giving program.
AdelaideAqua’s two tunnel boring machines (TBMs) were christened Nessie and Cora the Bora by local students, honouring a long-held tradition of naming TBMs.
The project’s permanent visitor centre will feature a keeping place for indigenous artefacts found on the site, and the landscaped walking trail will feature dual-language interpretive signage.
While the Consortium is committed to using a predominately local workforce, a skills shortage was identified within the welding industry working with glass reinforced polymer (GRP) and super duplex stainless steel.
Supported by SA Water, AdelaideAqua have launched the Welding Training & Testing Initiative (WTTI).
With a target to train at least 100 people in boilermaking, stainless steel and GRP welding, metal fabrication, and quality assurance, the WTTI will create skills transferable across a number of industries specific to South Australia including the defence, wine and automotive industries.
AdelaideAqua are indeed ensuring that they leave a legacy with implications for all South Australians.