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Customer: Auckland Council Contract: Construct Location: Papakura, South Auckland, New Zealand   |
Fast Facts
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In one of the largest trenchless project to be undertaken for Auckland Council, we installed nearly all of this 1.1 km long, 2.5 m diameter stormwater pipe using trenchless technology. The new pipeline connects the McLennan Park stormwater ponds with the Pahurehure outlet and is designed to meet the growing population of South Auckland.
We used a closed-face slurry Micro Tunnel Boring Machine (MTBM), except for a short section constructed using open-cut methods. We also constructed five deep manholes and inlet and outlet structures.
The project involved extensive work in McLennan and Katavic Parks, with park access remaining open during construction. We implemented stringent safety and environmental management, with groundwater discharge and monitoring the most significant consent compliance requirement.
We encountered greater than expected groundwater levels on-site, which required a change in methodology for shaft construction. For shafts four and five we used a secant piling method with augured piles. The five shafts ranged from 6 m to 13 m deep.
Despite the unforeseen ground conditions, the project stayed on track, thanks to having the right machine for the highly variable ground conditions and an in-house design team able to quickly adapt designs to suit the conditions encountered on-site.
We implemented control plans and allocated people to ensure compliance across quality, safety, and environmental aspects, to ensure we delivered what we promised.
