Army Bay Outfall

Army Bay Outfall

Introduction

In 2017, Watercare engaged McConnell Dowell to install a new wastewater outfall, upgrade the existing pump station and build a new ultraviolet disinfection facility to increase the outfall capacity for its Army Bay Wastewater Treatment Plant at Shakespear Regional Park on the Whangaparaoa Peninsula, a pest-free conservation area. McConnell’s awarded a contract to Solo to assist them with the PE pipe welding and installation.

Challenge

The new outfall had to be built within the park without impacting the operational capability of the existing wastewater treatment plant and without compromising the pest-proof fencing to keep predators out. Most of the construction had to take place within the conservation area so it was important that the site footprint was kept as small as possible and environmental risks were well-managed. Ecologists collected and relocated many species before work began and the project needed to be completed as quickly as possible to allow animals to return to their natural habitats as soon as the works was complete.

The Solution

Solo was engaged to weld and install 1.9km of 1100mm HPDE pipe, 1km of which would be driven out to sea using state-of-the-art Direct Pipe tunnelling technology. Because timing was a critical factor, Solo setup a dual welding operation, welding in tandem with two machines to support McConnell meeting their deadlines and helping them to set a world-record for the longest Direct Pipe drive at 1,929 metres!

Army Bay Outfall
Army Bay Outfall