Bridges

NZTA’s Manukau Harbour Crossing project on Auckland’s South-Western motorway was delivered by the MHX Alliance in late 2010 - on budget, open five months ahead of programme, to a high standard and with satisfied stakeholders. The project is notable for its bridges – all different, and ranging in scale from a timber boardwalk to the 13,800 m2 centrepiece of the project, the 100m span twin box girder balanced cantilever Duplicate Mangere Bridge. The design and construction of the Duplicate Mangere Bridge over a period of 30 months was key to the early project delivery, and was achieved via construction innovations, sustained effort and a high level of continuous interaction between the design and construction teams. However, the most prominent bridge on the project is the Beachcroft Avenue pedestrian/cycle bridge, with its striking raked white pylon and stays supporting a blue truss over the widened motorway. This structure is the most visible legacy of the Alliance’s culture of pride and excellence. Nonetheless some local stakeholders consider the curvaceous little Onehunga Harbour Road bridge to be the pick of the bunch, because it enables them to safely walk or cycle between Mangere Bridge and Onehunga. This paper briefly describes the Manukau Harbour Crossing bridges, and captures some thoughts on how the processes of concept design, community consultation, detailed design, temporary works design, construction, construction monitoring, quality closeout and handover were able to be successfully managed in the Alliance environment to achieve an outcome which has delighted the client and in which the Alliance takes great pride. A link is drawn between the benefits of the Alliance environment and the delivery of "Sustainable Bridges".