CRL SCALES NEW HEIGHTS RESTORING ITS OWN ‘EVEREST’
30 April 2024
Work that began with hand-held spades in the ground four years ago came full circle today with City Rail Link (CRL) today celebrating the end of work to shift one massive pile of dirt and then replace it with another at the project’s Maungawhau Staton site.
Removing a large sloping hill in Eden Terrace cleared the way for construction of the southern tunnel portal connecting CRL with the new station and the North Auckland/Western rail line. The hill has now been restored and most of the heavy construction hidden underground.
“In many ways the hill was CRL’s ‘Everest’ – a mountain of a job completed successfully with larger-than-life high-tech machines and wonderful innovation that demonstrate the huge size of CRL’s work and all the complexities and challenges that come with that,” says City Rail Link’s Chief Executive, Dr Sean Sweeney. “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 an historic colonial cottage perched above the hill was safely relocated, the first spades of dirt were removed from the hill at an official sod turning ceremony in February 2020. Spades quickly gave way to heavy machinery – in the months that followed more than 130,000 cubic metres (1300,000m3) of material was carved away by CRL’s main contractor, Link Alliance.
In the hill’s place a line of 71 concrete piles between 42 metres and 8 metres long were driven deep into the ground to anchor a sweeping curved retaining wall 127 metres long and 25 metres high – a buttress of concrete and steel to support CRL’s southern portal and the streets above it.
One of the most celebrated ‘visitors’ to the portal was Dame Whina Cooper, the project’s tunnel boring machine. From there it launched its two underground drives into the heart of Auckland’s midtown to excavate the rail tunnels.
Cut and cover tunnel construction was completed last October, clearing the way for the next massive programme of work – restoring the hill.
On average a convoy of 45 trucks a day transported backfill spoil from quarries in south-east Auckland to the Maungawhau site. Measured monthly, the amount of spoil was the equivalent of 13,000 cars, or 100 blue whales.
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 tonnes of dirt now cover the complex and significant structures built below. I am proud of the teams involved in achieving this enormous milestone,” Mr Dudouit says.
Mr Dudouit says each layer of backfill was carefully compacted to ensure the restored hill was safe and secure for future use.
Compaction has prepared the restored hill for future use by Eke Panuku, Auckland Council’s urban regeneration organisation. A street above the hill will also be re-aligned back to its original shape.
For more information please contact:
Ewart Barnsley, CRL Media Advisor
M +64 21 567 862 | E ewart.barnsley@cityraillink.govt.nz
City Rail Link Ltd | Level 2, 25 Teed Street, Newmarket, Auckland 1023 PO Box 9681, Newmarket, Auckland 1149, New Zealand
About the City Rail Link (cityraillink.co.nz)
CRL is New Zealand’s largest ever transport infrastructure project, involving construction of a 3.45km twin-tunnel underground rail link up to 42m below the Auckland city centre. It will transform the downtown Waitematā Station (Britomart) into a two-way through-station that better connects the city’s rail network and more than doubles rail capacity across Tāmaki Makaurau. Two new stations Te Waihorotiu Station – to become New Zealand’s busiest station when CRL is fully operational – and Karanga-a-Hape Station – the country deepest station – are being constructed as part of the new modern urban railway link, while Mt Eden Station is being rebuilt and renamed as Maungawhau Station. CRL works closely with Auckland iwi through its Manu Whenua Forum to develop a new railway that is not only world class, but one whose award-winning design reflects New Zealand/Aotearoa’s unique cultural heritage. The project is funded jointly by the Government and Auckland Council.