Fletcher Construction

CATEGORY 4: Projects with a value greater than $50 million

Not your average highway project

The Ngauranga to Aotea Upgrade forms part of the NZ Transport Agency’s Wellington Northern Corridor RoNS programme and is part of the wider Wellington Smart motorway that runs between Johnsonville and Petone to the Terrace Tunnel. Ngauranga to Aotea upgrade was a complex engineering project for Fletchers and careful monitoring was required to ensure that the very considerable risks to road user safety and worker safety were managed, as well as environmental risk factors. The key construction elements were: Lifting and moving the old Aotea bridge at Kaiwharawhara CATEGORY to form part of the new northbound lane; 4 FINALIST lifting out existing gantries, lengthening and re-installation along with fabrication of entirely new gantries; widening to three lanes the existing SH2 off-ramp through to the Jarden Mile intersection; construction of a new southbound on-ramp for emergency services from the Jarden Mile intersection city bound; upgrading and reprogramming the intelligent transport system, including new sensor loops and radars; constructing a new northbound lane on State Highway 1 between Aotea on-ramp and Ngauranga in Wellington; and developing and implementing the country’s first smart motorway between Johnsonville and Petone and the Terrace Tunnel.

Following investigations in 2012, the 18-month construction programme started in late 2014 and was completed in June 2016. It involved closing Wellington’s urban motorway for the first time in living memory to install new overhead gantries.

“Closing the motorway was just one of the challenges the Fletcher Construction team successfully overcame to build the NZ Transport Agency’s first smart motorway,” says the company.

An unusual feature of this project was the amount of work carried out during night shifts, due to the nature of working on a live motorway.

From a client point of view the months of planning, including motorway closures, all went smoothly. Says the NZTA, “Fletchers managed the job very professionally and competently throughout the project. Despite the challenges posed by the site health and safety and environmental standards were managed and maintained to a high standard.” l