Drought-proofing Auckland City by reinstating a decommissioned dam

Hays Creek Pipeline

Since the beginning of 2020, New Zealand’s largest city, Auckland, has received significantly less rainfall than normal which has had a big impact on their water supply. As part of the drought response, Watercare asked us to support them to design a pipeline to transport 12MLD (millions of litres per day) from the Papakura Water Treatment Plant to the water network in Papakura. 

We were engaged under a rapid response model to undertake pipeline route alignment, pipeline design, geotechnical and pipe bridge structural design. The outcomes-focused approach involved working closely with Watercare and its supply chain to deliver designs that enabled rapid construction and commissioning of the pipeline. Key elements of design included an initial 1km (0.62 miles) of 600mm (23.6 inches) diameter pipeline and a pipe bridge across Hays Creek, plus a further 1.5km (0.93 miles) of 500mm (19.68 inches) diameter pipeline.

Our early engagement with the supply chain allowed for more off-the-shelf materials and a reduced design and lead time for materials supply. The result? Saved time and cost in procurement and delivery, and increased resilience and operational flexibility of Auckland’s water supply system.