Ohakune’s taps have been dry since Sunday and the central North Island town will not get its water back until Tuesday evening at the earliest, after engineers warned that refilling an earthquake-damaged pipeline too quickly could break it all over again.
The problem traces back to the magnitude 5.9 earthquake that struck near Taumarunui on 25 July. The shaking damaged the five kilometre raw water pipeline that carries untreated water down to Ohakune’s treatment plant. Much of that line is buried and runs through heavy bush on difficult country near Mount Ruapehu, which is a large part of why the fault took a fortnight to find and fix properly.
Crews got to the break on Friday. That repair is where the second problem began. In its update on Monday morning, Ruapehu District Council said the work “resulted in an airlock that prevented raw water from reaching the treatment plant, leaving Ohakune without a reticulated water supply”. In other words, the pipe was mended but full of trapped air, and the plant at the bottom of it had nothing to treat.
What followed was a slow-motion emptying of the town’s reservoir. According to the New Zealand Herald, the reservoir sat at 70 per cent on Friday night. By Saturday it was down to 12 per cent, which is when residents were told what was going on. By Sunday it had run out altogether, and tankers, bottled water and portable toilets started arriving.
That sequence is the part locals are angriest about. Barry Murphy, who chairs the Ohakune Ratepayer and Residents Society, told the Herald that people had been asked on Friday to conserve water without being told why, and that a fuller explanation did not appear on social media until Sunday afternoon. “Why were no alarms going off then,” he said. “Surely someone could see that the reservoir was dropping.”
Ruapehu mayor Weston Kirton has acknowledged the frustration and said the repair has been harder than the council first thought. He told RNZ the pipeline runs through mountainous terrain and that the council would need to establish the full extent of the earthquake damage.
The council had been aiming to have water back by 5pm on Monday. That target moved again during the day. Technical analysis found that taking the raw water pipeline from no flow to full flow too quickly risked fracturing it a second time, and the council said “a slower, controlled approach is therefore needed to protect the repaired infrastructure and safely restore the town’s water supply”. 1News reported the new target as about 5pm on Tuesday.
Veolia, the council’s water services contractor, has brought in extra staff and gear from Whanganui, Auckland and Central Hawke’s Bay. Much of the work has been the unglamorous business of finding valves. Sections of the pipeline are buried in bush and some of the valves needed to bleed air out of the system were not where anyone could easily reach them, so crews have been locating hidden ones and installing new ones as they go. The plan is to recharge the network starting from the treatment plant end, so the parts of town closest to the plant come back on first.
For a town of roughly 1,300 permanent residents in the middle of the ski season, three days without running water is not a small inconvenience. Emergency water has been available from the council office at 37 Ayr Street, where people can refill containers, and 1News reported that about 5,700 containers have been handed out along with extra tankers around the town.
Businesses have worn the cost. Remi Butler, who manages the Peaks Motor Inn, told the Otago Daily Times that a full house booked for two nights had cancelled. “I don’t think insurance will cover anything like that,” she said. “We’ll just have to wear it.” Samuel Fletcher, who owns the local New World, has kept the supermarket trading. “We follow food safety procedures for something like this,” he told the paper. “We’ve got that as part of our food control plan.”
Ruapehu College sent its roughly 250 students home, with principal Kris Vine checking the situation hourly and putting health and safety first. Iwi representative Helen Leahy raised concerns about vulnerable families, the school closures and the hit to hospitality businesses during what should be one of the better trading months of the year.
When the water does come back, the council has warned it may look wrong before it looks right. People should expect it to have a milky or cloudy appearance at first, caused by harmless air bubbles trapped in the water as the network recharges, and the council has said this is not a cause for alarm. Residents have been asked to turn all their taps off during the restoration so the system can fill in an orderly way, and Veolia staff will be spread across the network with handheld testing equipment confirming the water is safe before it is signed off.
One detail worth holding on to is that the treatment plant itself is fine. Ohakune’s plant was upgraded last year at a cost of about $10 million and has stayed fully operational throughout. The damage is entirely in the old raw water line feeding it, a pipe reported by the Otago Daily Times to be around 70 years old, running five kilometres through terrain that makes every repair a small expedition.
That is the quiet lesson in this one. An earthquake a fortnight earlier, centred well away from the town, did not knock a building over in Ohakune. It cracked something buried in the bush that nobody could see, and the consequences turned up a fortnight later as empty taps, closed classrooms and cancelled bookings. New Zealand has a great deal of ageing pipework in hard country, and very little of it announces its own failure. The council has said it will now look at the full extent of the earthquake damage along the line, which suggests Friday’s repair may not be the last one.
Have you been caught up in the Ohakune outage, or does your own town rely on a pipe like this one? Tell us in the comments below.
This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂
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