Thousands of Aucklanders to walk the City Rail Link for a peek into the future

Thousands of people will tomorrow get the chance to walk through the dual tunnels for the City Rail Link in the central city. Photo / Jason Oxenham

Ten thousand lucky Aucklanders get the chance to walk the City Rail Link tunnels tomorrow, but it's the next stage of the $4.4 billion project where the best is to come.

"It's at the end of the beginning," says City Rail Link Ltd chief executive Dr Sean Sweeney, quoting from Sir Winston Churchill concerning the Second Battle of El Alamein.

Sweeney is referring to the main contract which involves building two new underground stations in the central city and Karangahape Rd and boring two tunnels from a 3.6ha site at the Mt Eden end of the new 3.4km rail line.

Work stopped on the CRL works in the central city yesterday to get ready for people fortunate to have one of the 10,000 free tickets that got snapped up in 15 minutes.

After three years of work and disruption that has brought several small businesses to their knees, the public will be able to walk a 600m round trip of the twin concrete tunnels that stretch from Britomart, under the new Commercial Bay development and up lower Albert St to the historic Shakespeare Tavern on the corner of Wyndham St.

The next time people go underground at the Britomart end will be on a train when the CRL is completed towards the end of 2024.

Numbers had to be restricted to safely manage 10,000 people walking through a confined underground "live" construction site, which meant there was no flexibility for another open day, said Sweeney.

After tomorrow, Sweeney and the Link Alliance of six New Zealand and international companies building the main stations and tunnels will be back at work, focusing on the job ahead.

"There has been a lot of work to date, but this is where it gets major," says Sweeney.

City Rail Link Ltd chief executive Dr Sean Sweeney. Photo / Greg Bowker

Currently the Link Alliance is demolishing buildings for sites at Karangahape Rd and Mt Eden and undertaking early works for the new Aotea Station below Albert St for 450m between Victoria and Wellesley Sts.

From March next year, construction will begin on piles and reinforced concrete walls at the Aotea Station in a top down construction method less disruptive to the works in lower Albert St, but still bad enough to cause headaches for about a dozen businesses and motorists for several years.

Sweeney says CRLL is trying to learn from what did not go well in lower Albert St but there are certain physical impacts, like safety fences and 250 to 300 trucks a day removing spoil, that cannot be avoided

Work on boring the twin tunnels with a 7.15m diameter boring machine - the Waterview boring machine had a diameter of 14m - will begin in early 2021 once buildings, plant and the portal are completed at the main building site in Mt Eden.

Mt Eden station, which is being rebuilt at ground level, will close from mid next year until the project is finished.

The first tunnel will take about nine months to bore to Albert St via the Karangahape and Aotea stations. The boring machine will then be removed and taken back to Mt Eden where it will bore the second tunnel in 2022.