If you are a passenger on the TranzAlpine train between Christchurch and Greymouth, you’ll be unaware of any drama while travelling through the Ōtira tunnel, between Arthur’s Pass and Ōtira, apart from the fact that the train’s observation car is closed for the trip through the tunnel.
As you sip your wine from the comfort of your seat, in your air-conditioned carriage, this major feat of engineering, on a line full of major engineering feats, is still the high point. Perhaps you might reflect on what it might have been like to be part of the lengthy process of building this tunnel, completed almost 100 years ago.
The end of the world
Weeks and months in the semi-dark, breathing foul air, the weather outside, the water inside, the noise, the dust, the relentless grind, for 15 long years. At the time, this was New Zealand’s biggest ever engineering project, the country’s longest railway tunnel.
The late Tom Ferguson was a child when his parents lived in the camp at the Ōtira end of the tunnel, his father working in it for nine years. His mother thought it was the end of the world.
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“It rained for weeks, she cried for weeks, and I hardly ever went to school, because of the rain and the storms,” Tom told me in an interview in the 1980s.
The plan for the tunnel was to at last link Westland with Canterbury. A mighty 8.6 kilometre hole would pierce the mountains, with a steep upgrade up from west to east, rising some 250 metres.
John McLean and Sons began work on the dauting project in 1908, but it became a monster for them, with a rockfall killing one man, and entombing tunnellers Duggan and Doyle for 86 hours. Another man died in a landslip.
There were frequent union troubles. Union delegate Bob Semple, later to be Minister of Works, said “the men were wet through by halfway through the shift, and so caustic was the water cascading from the roof that men could get terrible sores”.
John McLean and Sons gave up their contract, leaving the government, through its Public Works Department, to finish the project, which it finally did in August 1923. When both ends broke through, they were less than 11 centimetres out of alignment. This showed the remarkable accuracy of the surveyors, using special theodolite stations at each end.
From the start, electric locomotives were used because the steep grade and the length of the tunnel meant using steam engines would never be possible. They always knew this tunnel would have unique challenges, be different from all others, and would need a special type of maintenance programme.
David Jackways is KiwiRail’s business strategy manager for the South Island. He describes the Ōtira Tunnel as a significant feat of engineering.
“It is constructed at the maximum gradient allowed on the network, although there are a couple of short sections that are steeper. To replace the tunnel today would cost well over $4 billion, so it is a very valuable asset connecting the east and west coasts.”
Working the tunnel today
Anit Lal has always liked trains. He was brought up in the city of Pune in India, with his father taking him to see the trains and to ride in them. He completed his Master’s degree in Engineering Management at Canterbury University, and is now KiwiRail’s field production manager in charge of the Midland Railway Line, from Rolleston to Greymouth. He knows all about the track along this line.
“My job is to keep the line in top condition, with twice-weekly full inspections, and to manage emergencies such as flooding, washouts and slips,” he explains.
“In the tunnel, water is present all the time, more so in the rainy season. It comes down from the roof and a drain in the tunnel is full most of the time.”
Lal says the steep grade creates unique issues. “Our vehicles have to have good dual braking systems, regularly tested, as brakes can heat up. Going uphill from Ōtira, there are special arrangements for flushing out bad air.”
With so much power used hauling trains up the grade, a special ventilation system was needed. Automatic doors at the Ōtira end close once a train is inside, sealing off the tunnel, at which point large fans suck foul air out to allow the locomotives to breathe.
A moment of madness
Mike Morgan is a locomotive engineer specially qualified to drive in the tunnel. He came to Ōtira almost 20 years ago in “a moment of madness”.
He loves his work, his team of colleagues, the lifestyle, and even the weather.
“People ask me about the weather. Well, I came from Hamilton, and it rains a lot there.”
Morgan is one of a small group of specially qualified locomotive engineers allowed to drive four dedicated locomotives stationed at Ōtira. These are known as “bankers”. Their job is to help heavy trains up and down the grade.
Each train has an assistant on board to help in case of emergencies. An emergency could be a breakdown, or an earthquake.
“We used to have regular breakdowns when we had only three banker locomotives, which used to overheat”, Mike says, “but now that we have four, providing more power, we don’t really have issues.”
Dave Morey came to New Zealand with a dream of driving trains, so he did his training before spending two and a half years driving the bankers in the tunnel.
He laughs at the idea of a breakdown. “I never had one, even though I was always prepared for an emergency.”
People used to ask him why he liked spending so much of his time in the dark. “I wanted a job with challenges. I like being ready for when a big decision has to be made.”
Safety vital
Mike Morgan says the safety measures in place are excellent.
“In the cab we have a sophisticated monitor to measure oxygen, nitrogen and carbon monoxide. We also have a thing that looks like the kit a scuba diver wears. It’s called a CABA (Compressed Air Breathing Apparatus) and includes gas bottles and professional mask, and we have to be trained to use it.”
There are two sets in each cab, as well as at six stations in the tunnel, in case there is an emergency. Every three weeks the kilometre markers on the tunnel walls are waterblasted, so crews know where they are.
Morgan is enthusiastic about the professional way KiwiRail has modernised safety measures in the tunnel.
“A lot of thought has gone into all this, lots of time and resources. The tunnel is not for the faint-hearted, being very long and dark, and with trains limited to 28-30 kilometres an hour, it takes a while to get through.”
Morgan and Morey agree that it takes a special sort of locomotive engineer to enjoy being in the tunnel. Fog is another unexpected feature of their role, as warm and cool air gets mixed in the tunnel.
Lal says they have recently upgraded and replaced parts of the new communication system in the tunnel, which he describes as brilliant. “It’s called a Leaky Feeder cable, and it allows for complete coverage on three channels,” he explains.
The drama continues
For the TranzAlpine passenger, sipping that glass of wine, or enjoying the good food on board, the only thing noticeable when stopping at the ends of the tunnel will be the adding of two banker locomotives at each end of the train.
This means that if there is an emergency, the train could be hauled out in either direction. On each trip, the TranzAlpine’s driver will move into the passenger cars, which are sealed so no air can get in, and the open air car is locked, while the banker drivers take control.
It would indeed be interesting for one of those original tunnellers, to be the proverbial fly on the wall, to see that all the toil was worth the sacrifice. One hopes that he, and his family, like that of Tom Ferguson, would be proud that today almost three and a half million tonnes travels in and out of the Ōtira Tunnel each year.
To commemorate the opening of the Ōtira Tunnel in August next year, major celebrations are being planned, involving the Ōtira and Arthurs Pass Communities, Engineering New Zealand, KiwiRail, and the Department of Conservation.
Simon Williams is a journalist, TV producer, and media educator based in Christchurch.
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