130,000 cubic metres of material were removed and replaced in the epic construction project. Video / City Rail Link
No fatalities and no lava flows in tunnel’s way; Auckland’s City Rail Link nears completion, opening in 2026.
Dr Sean Sweeney leaves $5.4b project to lead Ireland’s $20b MetroLink from September 16.
90% of CRL contract work completed; first test train scheduled for later this year.
No fatalities on New Zealand’s largest infrastructure project and no basalt lava flows impeding construction of the two main tunnels are reasons to be glad about the state of Auckland’s nearly-completed City Rail Link project, expected to open in 2026, says its outgoing chief.
On September13, Dr Sean Sweeney finishes as chief executive of that $5.4 billion job and he discussed those aspects and many others before leaving.
On September 16, the European passport-carrying civil engineer whose father comes from County Mayo begins Ireland’s largest infrastructure project.
City Rail Link chief executive Dr Sean Sweeney observing construction at Te Waihorotiu Station on November 21, 2023. Photo / Dean Purcell
On June 25, it was announced he had been appointed programme director for Dublin’s $20b MetroLink project.
That is five times the size or cost of CRL and is to run nearly 19km, mainly below Dublin but also above ground.
Just before leaving, the Kiwi engineer looked back on his years with CRL, the successful Link Alliance achieving 90% of its contract work by late July and the joys of this job with the first test train scheduled for later this year.
He doesn’t want to go.
“I would have preferred to stay in New Zealand. I love New Zealand. I’m a passionate Kiwi. I’m coming back here after the [Dublin] job.”
Talking to the Herald from CRL’s offices on Newmarket’s Teed St, Sweeney says he has no regrets.
But he sure is annoyed about this city and country’s lack of dedication to creating infrastructure, particularly in Auckland where he cites the 1959 Auckland Harbour Bridge as an ailing example here.
Failure on water and wastewater are other concerns he has.
Dr Sean Sweeney says he would prefer to stay in New Zealand but there are no big new projects for him to work on. Photo / Dean Purcell
A new report, The State of the City, compares Auckland to nine other peer cities and Sweeney cited that as illustrating how the city was drifting backwards, “a lack of infrastructure steadily eroding productivity”.
After speaking out to TVNZ’s 1News about the poor infrastructure planning and delivery, he said: “My phone went mental. I had feedback from every part of the construction industry. No one said you got it all wrong. That’s the whole industry.”
No fatalities
“I’m relieved there were no deaths on the job but it’s not finished yet. It was something I would worry about all the time.”
All up, around 10,000 people worked on CRL, Sweeney says.
Stringent health and safety protocols safeguarded that workforce.
But Sweeney says one worker who had taken a drug caused an accident resulting in another suffering multiple fractures.
“We had only one serious injury and that was a guy high on meth. He knocked someone off the formwork. He drove out of control towards a piece of formwork and knocked a man off it.”
WorkSafe investigated the accident but decided to take no further action and the worker who caused the accident left the job and the country for Australia, Sweeney recalls.
Rocks
The Maungawhau Mt Eden end of the project where basalt rock was found and had to be blasted. Photo / City Rail Link
Striking basalt lava flows was another concern before tunnel excavation began.
The potential of lurking lava rock flows was a big threat to the tunnel boring machines, Sweeney said in 2019.
Volcanic rock was certainly found in the ground at the Maungawhau Mt Eden end of the project and had to be dealt with.
Fortunately, such rock was not present in the path of the tunnels further below ground.
Ground testing via bores and route planning avoided this.
The lava flows which were struck were blasted because that was the most effective way to deal with them, Sweeney says. Controlled explosions were needed to excavate two trenches, necessary for the tunnel boring machine to get into the tunnel portal at Maungawhau.
In June 2020, CRL said it was blasting rock. Sweeney said the seam was the worst of both worlds: fractured therefore not strong enough to hold up while the trenches were dug towards the twin underground tunnels but also in the way of the project.
Special blasting mats were placed over the charge site to minimise rising dust and prevent rock from flying.
Doubters - how he responds
The City Rail Link has moved beyond the civil stage and hundreds of kilometres of cables are being laid to run the stations and trains. Photo / Corey Fleming
How does Sweeney respond to doubters or critics who say the CRL is too expensive, it won’t be used much, it’s useless and took too long?
“Nothing. I can’t be bothered. They’re like flat-earthers.”
But then - he can’t resist.
“City Rail Link is equivalent to 16 lanes of motorways running 20km out from the CBD. Just tell me those suburbs we are going to demolish to build those motorway lanes? No one has told me which suburbs would be up for demolition.”
The twin 3.45km tunnels beneath the city will connect Waitematā Station with others and vastly increase the efficiency, reliability and frequency of our passenger rail network. The tunnels have been excavated at a maximum of 42m beneath the ground.
“I have been more than honoured to lead CRL and with our finish line approaching rapidly it was no easy decision to leave a project that will always remain special to me. It will not only do so much for Auckland and Aucklanders, but CRL demonstrates the very best in outstanding teamwork, innovation and design. Every one of us who have worked on CRL can rightly feel proud and privileged to have done so.”
Tunnellers long gone
Tunnels beneath the ground on a giant scale. Photo / City Rail Link.
An expert international tunnelling crew left New Zealand, with the completion of CRL’s underground twins.
So if we’re up for another tunnel project, like a second harbour crossing, specialists will need to be imported.
That means building infrastructure such as tunnels will cost so much more for New Zealand than it does for other countries, even those with similar-sized populations like Ireland, he says.
In a keynote address at the NZ Rail 2023 conference in Auckland, Sweeney said New Zealand is the most expensive country in the world to build new infrastructure.
The cost per kilometre for building a “metro” or rapid transit rail line in New Zealand is US$922.37 million ($1.493 billion). This is an estimate of the cost of the CRL.
But in the United States, where costs are also regarded as expensive, it’s a third less, at US$601.85m/km.
In Australia, it’s only US$321.43m/km, which is almost two-thirds less than the New Zealand figure. France gets the work done for less again: US$255.55m/km, the Herald reported him saying last year. Sweeney’s figures come from research by the Transit Costs Project, a private research company attached to New York University’s Marron Institute of Urban Management.
Dublin-bound
Dr Sean Sweeney is proud of his working-class roots. Photo / City Rail Link
Sweeney is looking forward to living in Dublin, skiing in Europe and the challenges of the new role such a large project brings.
“There’s a strong personal element involved and the chance for an Irish/Kiwi like me to reconnect with family in Ireland.”
How did he get that Dublin job? A call came out of the blue from London-headquartered head hunters Newsom Consulting on behalf of MetroLink and Sweeney thought he was only being asked to make up a shortlist.
“I went to Dublin to meet them in February.”
MetroLink is planned to be built between central Dublin and the city’s airport and connect with existing road and rail public transport.
It is to be almost 19km long, most of it underground, with 16 new stations.
The project could last years but Sweeney’s ultimate plan is to return to New Zealand.
“I am an outlier. I left New Zealand because there were no big projects. I came back 20 years later and now there’s nothing when CRL finishes. If there was, I would not be going to Dublin.”
Anne Gibson has been the Herald’s property editor for 24 years, written books and covered property extensively here and overseas.
