Erupting mud closes busy road
Boiling mud erupted on a Rotorua traffic island on Wednesday morning, startling motorists and onlookers.
Peak hour traffic was able to use Lake Road by 5pm, Rotorua Lakes Council said, but it would close again after rush hour.
Council staff are trying to figure out how and why the fumarole (steam-driven geothermal event) occurred on the busy road about 9am yesterday.
Investigations continued yesterday afternoon, the council said, at which stage the unexpected geothermal display hadn’t been linked to a bore.
‘‘Investigations will continue in the morning. If the activity is not linked to a bore, it is likely work will get underway to quench and fill the fumarole tomorrow.’’
Work continues to clear mud and water from the road and to prevent any further overflow from entering the Utuhina Stream.
The fumarole popped up in the middle of a traffic island opposite Kuirau Park (an active geothermal area on the outskirts of the central city) spewing steam and boiling mud across the road.
It also appeared to have cracked the road surface. Contractors closed the road to traffic heading into the city at the corner of Lake Rd and Tarewa Rd and detours were in place.
Council geothermal inspector Peter Brownbridge, who was at the scene yesterday morning, said he was not entirely sure why the fumarole popped up where it did. ‘‘We are turning off some of the local geothermal bores, just to be safe,’’ he said. ‘‘This is not a known hotspot, so it is unusual.
‘‘If it’s not the local wells we will have to let it do its thing and just wait. But, it could be moving underneath the road surface.’’
He said there were no records of any hot springs where the fumarole appeared.
‘‘The fumarole is not particularly large, it popped up amongst plantings in the middle of a traffic island, but there’s a fair bit of water and mud on the road on the side going into town, so we’ve closed that off for now.’’
It is not known if the crack across both lanes on the other side of the road was related to the fumarole.
‘‘We’re not detecting any heat or movement from the crack so that side of the road remains open for now.
‘‘We have well drillers here now looking to quench one of the bores to see if that affects the flow of water coming out of the fumarole,’’ Brownbridge said.
Rotorua resident Paul Wilson was cycling down Lake Rd and stopped to take some photos.
‘‘My friends overseas can’t believe where we live, they say it looks like we are living on the moon when they look at the geothermal activity around our city.’’
Wilson said he was no expert but, ‘‘I think this will cost a bit of money due to the damage it’s causing to the infrastructure’’.
‘‘I can see a roundabout here in the future, possibly with a nice geothermal attraction in the middle,’’ he joked.
A woman who lives near the newly formed fumarole said she didn’t see it happen but raced home to make sure her house was safe.
‘‘I suppose it’s fortunate it happened in the middle of the traffic island,’’ she said.
According to the Rotorua Lakes Council’s website, the activity ‘‘. . . is likely to be linked to high groundwater levels’’.