Thermal row bubbles on

Ohinemutu residents Api (left), Jim Tait, Rangituatini Sinnott and John Waaka are worried about the increased geothermal activity in their village.

Rotorua residents are questioning whether the recent roadworks on Lake Rd are connected to the geothermal uprisings in Ohinemutu.

A section of Ariariterangi St was blocked off by Rotorua District Council just under three weeks ago as a safety precaution after an increase in thermal activity and a rise in ground temperature. Council staff have conducted daily testings.

But the local authority said there was no evidence of any connection to recent upgrade works on Lake Rd or anywhere else. It said any problems were under control and there should be no need for concern.

Residents have reported the affected area has spread and are concerned for their properties. A local, who only wanted to be known as Api, said he had to dig a trench in his front yard to relieve the pressure from a ngawha (hot spring) vent that had become active. He said he believed a combination of a re-drilled bore opposite his property and the roadworks had contributed to the problem.

"It's never blown for more than 40 years I've lived here. Has the ngawha under Lake Rd been blocked when they did those roadworks?" he asked.

"More ngawhas are coming up on our property and the council doesn't seem to be interested in it, they're just worried about the road. At the end of the day, we don't really need that road, but we always need our ngawha for cooking and bathing."

Rangituatini Sinnott has lived in her family homestead on Ariariterangi St all her life and said the uprisings were the worst she had seen. The 53-year-old said they were taught as children to respect the land and how to live as one with the thermal activity.

"We've always known we're sitting on a bubbly ngawha, hence all the vents in the middle of the road, they are all outlets," she said.

"From the knowledge that was passed down to us, we're like a vein, our main pool runs from Kuirau Park.

'I strongly believe there is a connection with the roadworks that were done at the traffic lights on Lake Rd. Did they give the appropriate outlets to cover the streams or did they just fill up the streams and the outlet has now found its own exit?

"Working at the marae, we've noticed the different pressures of the ngawha and the steam boxes.

"We shouldn't run out of hot water but that is what is happening. The only time we've run out is when we we're feeding 1000 people each day for a big hui [meeting] or tangi [funeral]," she said.

"What is happening now is very, very scary because it's straight across the road from me and it's actually cruising on to my next door neighbour's section. We don't know if the heat is going to take away the road and turn it into a big ngawha pool."

Council infrastructure services group manager Andrew Bell said the problem was solely related to the condition and age of a bore on a neighbouring property.

"Further testing by technical experts over the weekend reinforces the aged bore scenario as the only likely cause," he said.

"As part of the council's investigations and testing, the bore was quenched on Friday morning and cold water was left to run through it. By the end of day, there was a noticeable cooling of the road and the grass area."

Mr Bell said by Saturday morning hot water on the road had stopped, ground temperatures were down and the heat had gone out of the grassed area.

"Checks again on Sunday showed the grass and road remained cold.

"The bore has now been re-started to reconnect heating to the neighbouring house as a temporary measure until a new replacement bore is in place and operating over the next few weeks. As expected with the bore being re-started, there is some cold water seeping over the road related to the deteriorated casing on the bore, but the grass area remains cool," he said.

"At this stage we're confident the situation is under control and there are no immediate concerns."