Rare mud eruption south of Rotorua at Wai-O-Tapu

A new eruption of steam and mud at Wai-O-Tapu Thermal Wonderland south of Rotorua has caught a man by surprise but a specialist says while it is uncommon it's not unexpected.

Thomas Rodda drives a shuttle from Rotorua to local sites and was taking passengers to Wai-O-Tapu on Saturday when he saw the mud spurting into the air.

"I go past that pool pretty much every day and I've never seen it do that."

There is a large mud pool at Wai-O-Tapu but Rodda said the hot mud and water seemed to be erupting from next to it.

"It took me a while to start filming. I was quite astonished to see it," he said.

"It's not like it's fenced off or anything."

Rodda said the eruption lasted roughly 40 seconds.

GNS Volcano Information Specialist, Brad Scott, said the Wai-O-Tapu area was an area with steam and mud features.

"It's not common behaviour but it's not unlikely or unexpected," he said.

"Occasionally we get reports of trees covered in mud and maybe something has happened overnight."

Scott said the eruption was not a geyser as geysers were hot water erupting and this was caused by steam.

"It's a mud eruption and it may not erupt again," he said.

"It could be caused by more steam oming through, more water on the stop, sometimes the climate changing."

Scott said as the area was public, people should be cautious when approaching the scene.

Mericia Waqanimaravu, the general manager of Wai-O-Tapu Thermal Wonderland, said the area where the eruption was is Department of Conservation land.

Thomas Rodda drives a shuttle from Rotorua to local sites and was taking passengers to Wai-O-Tapu when he saw the mud spurting into the air and took footage. Photo/Supplied

"As far as I know it's never erupted before but it's awesome to hear.

"Whether or not it's going to continue or it's a one-off, we'll just have to wait and see.

"If it continues it continues, it's what mother nature wants."

Waqanimaravu said she didn't see the eruption but it would have been quite a sight.