Rotorua: Bore erupts at marae, buildings and cars coated in ‘mud substance’
A geothermal bore that erupted with a geyser-like display at a Rotorua marae has been brought under control.
Hemi Waerea, a Ngāti Kea Ngāti Tuara hapū member, said it erupted about 4.30pm yesterday and was still going this morning.
Waerea said he “shot down” to Tārewa Pounamu Marae on Tārewa Rd after receiving messages about the bore erupting.
At least five buildings were affected, including a kaumātua flat and an office, he said.
A “mud substance” coated nearby buildings, and vehicles had to be moved because of the debris, Waerea said.
He said the plume was not as high on Wednesday as it had been on Tuesday night but had spread wider.
“The hole is sort of getting bigger.”
Waerea estimated the hole was about the size of a manhole.
While the bore initially expelled steam and small rocks, he said hot water was now coming out.
To plug the bore, workers planned to put a steel pipe down it before adding cold water and cement, he said.
Waerea said marae staff were monitoring their new spring.
“Living in Rotorua, it’s just an expected thing,” he said.
But looking out at the plume from the marae, he added: “You just don’t expect it to be there”.
Waerea said the marae’s general manager, who lived on-site, had noticed “a lot of activity” at geothermal pools behind her house.
“The pools have now dropped because the pressure has come out here,” he said, referring to the bore.
“Before that, it was bubbling over on to the ground and on to her backyard.”
A council spokesperson said a grouted private bore had failed, causing water, steam, mud and concrete to spray into the air in a geyser-like eruption.
The council was alerted about 4.30pm on Tuesday.
The site had been fenced off and the bore was controlled by this afternoon. Regrouting would begin tomorrow.
The council had been in contact with marae owners.
There was no damage to buildings and cars sprayed with the steam and mud could be washed with soapy water.
The council did not know the exact cause of the failure.
It understood the bore had been grouted in the 1980s.
Council geothermal inspector contractor Andrew Austin said there had been a slight increase in geothermal activity across Rotorua after recent heavy rain, which was normal and usually settled over time.
Dirk Hermson, from Barham United Welldrillers, told the Rotorua Daily Post he believed ground movement caused the bore to burst and gush into the air.
“We’re here to kill it. It can be quite challenging.”
He had to stop the water before it could be cemented off again.
The marae’s back entrance is at the Rotorua Aquatic Centre.
Steve Holmes, who took the video above, was taking his son to a swimming lesson when a “massive” 30m high column of water caught his attention about 5.30pm on Tuesday.
The water was still surging skyward when Holmes returned to his car about 45 minutes later, though it no longer appeared as “big” or “aggressive”.
Holmes said a fine mist settled on his vehicle, leaving what he described as a “white, murky” residue that dried into a powder.
Holmes later saw social media comments from another person who reported their car had also been coated in the residue.
The spectacle quickly sparked discussion online. Holmes said a video he posted to a Rotorua Facebook notice board had attracted about 900 reactions, showing “people were quite interested in it”.
Annabel Reid is a multimedia journalist for the Bay of Plenty Times and the Rotorua Daily Post, based in Rotorua. Originally from Hawke’s Bay, she has a Bachelor of Communications from the University of Canterbury.
Correction
An earlier version of this story said the incident was understood to have been caused by a burst water main. Rotorua Lakes Council said this was incorrect and has confirmed it was a bore.