McConnell Dowell is pleased to announce that Wellington Water has awarded the Barber Grove to Seaview Wastewater Treatment Plant Pipe Duplication to McConnell Dowell. 

The existing concrete pipeline conveys wastewater from 90 percent of Hutt Valley residents and is over 50 years old and highly vulnerable to earthquakes. 

Our solution involves a mixture of trenchless technology (55 per cent) and open trenches to install the pipeline. This method was chosen because it is the most efficient and will cause the least possible disruption to the road network, local residents and businesses.

This project located in New Zealand’s North Island, involves the installation of a new 1.2km, 1m diameter polyethylene pressurised wastewater pipeline from Barber Grove Pump Station to the Seaview Wastewater Treatment Plant.

This is an exciting project for the McConnell Dowell team who continue to build on an extensive track record constructing pipelines using trenchless methodologies in New Zealand, Pacific Islands, Australia and South East Asia.

McConnell Dowell Managing Director for New Zealand and the Pacific Islands, Fraser Wyllie says; “We are excited to work with our new client Wellington Water in the delivery of the new pipeline which will service 90 percent of the residents in Upper Hutt and Lower Hutt, improve water quality to cater to the region’s growth and provide a robust solution in the event of earthquakes”. 

The project consists of: 

  • 1.2km long by 1m diameter polyethylene pressurised wastewater pipeline installation under 3 – 9m deep below high-volume traffic routes
  • 55% of the alignment installed via Micro tunnelling
  • Four shafts along Randwick Road for access to the tunnel

The work will commence in February 2022, with completion due in early 2023.