By Lynda Myer
Following that the City Rail Link’s (CRL) main contractor, Link Alliance, removed one large pile of soil to build the metro railway in Auckland four years ago, currently this company is going to replace this hill another at the line’s Maungawhau Station site.
Eliminating of a large sloping hill in Eden Terrace smoothed the way for construction of the southern tunnel portal connecting CRL with the new station and the North Auckland/Western rail line, whereas the hill has now been restored and most of the heavy construction hidden underground.
According to CRL chief executive Dr Sean Sweeney: “In many ways the hill was CRL’s ‘Everest’ – a mountain of a job completed successfully with larger-than-life hi-tech machines and wonderful innovation that demonstrate the huge size of CRL’s work and all the complexities and challenges that come with that. This was building for Auckland’s future on a grand scale – all the materials we used can be measured by the tens of thousands.”
After a colonial cottage sited above the hill was relocated, the first spades of dirt were removed from the hill at an official sod turning ceremony in February 2020. In the months that followed more than 130,000m3 of material was carved away.
In order to supporting CRL’s southern portal and the streets above it, the hill’s place involves a line of 71 concrete piles between 8m and 42m-long were driven into the ground to anchor a sweeping curved retaining wall 127m long and 25m high.
The location of commissioning the project’s Dame Whina Cooper on the two drives into central Auckland, was the southern portal.
Considering that on October 2023 cut and cover tunnel construction was completed, the way for the restoration of the hill was cleared.
During the process, the number of convoy and trucks that transported backfill spoil from quarries in south-east Auckland to the Maungawhau site was 45 per day.
Link Alliance project director Francois Dudouit acknowledged the hard work of the 200 workers who worked for four years in the tunnel portal area.
“The area has been transformed, reshaped and filled back in again. Much of this extraordinary achievement is hidden from view as 85,000 tons of dirt now cover the complex and significant structures built below. I am proud of the teams involved in achieving this enormous milestone,” said Dudouit.
Additionally, Eke Panuku, which is Auckland Council’s urban regeneration organization, will use the restored hill for future. A street above the hill will also be realigned to its original shape.
As New Zealand’s first underground rail line and the largest transport infrastructure investment ever undertaken in the country, CRL is a 3.45km twin tunnel in downtown Auckland.
The Link Alliance comprises City Rail Link Ltd, Vinci Construction Grands Projets, Downer NZ, Soletanche Bachy International NZ, WSP NZ, Aecom New Zealand, and Tonkin + Taylor.
