Client: Cook Islands Government  Location: Rarotonga  Budget: NZ$ 31 million  Contract: Design and Construct  Completion: August 2019    Project Capabilities

Delivering fresh water to Rarotonga 

The largest infrastructure project ever undertaken in the Cook Islands, Te Mato Vai will deliver fresh drinking water to all residential and commercial properties connected to the existing network on Rarotonga. 

The current water supply in Rarotonga is untreated and the network has little storage capacity with much of the pipe work laid in the 1960s and requires replacement.  This can mean that in times of dry weather supply to some parts of the island is unreliable. 

Te Mato Vai will deliver a high standard new water network, improving the quality and capacity of drinking water. 

McConnell Dowell is delivering the second stage of the project for the upgrade of 10 existing water intakes at remote sites across the island, construction of 12 km of replacement trunk main from the intakes to the new ring main, and minor upgrades to the access roads to eight of the 10 intakes. 

Intake works involve the construction of new intake structures, sedimentation tanks, sand filters and bolted steel water storage tanks up to 20 m in diameter and 8.5 m high. To access the sites 25 ford crossings were required. 

The project is divided into four Separable Portions: 

SP1: Design of the new water treatment process 

SP2: Construction of the process facility 

SP3 (Build only): installation of 12km of HDPE pipe connecting the new process facilities to the existing network   

SP4: Commissioning of the plant.   

The challenge 

The intake structures are spread across 10 different work sites, from private land to challenging terrain deep in the mountains (including one at the top of waterfall!), making access difficult. 

The solution 

Vigilant planning has enabled us to install the structures safely in the challenging environment and maximise productivity across multiple work fronts. Extensive liaison with landowners has been essential to undertake the works required in private land with minimal disruption.  

Local employment and training 

We have engaged a significant number of local people and subcontractors on the project, injecting valuable income into the local economy. We have also trained a number of local staff as welders, providing them with valuable skills for use in future employment.