The volcanic eruption and 15-metre tsunami waves were created after underwater volcano Hunga Tonga-Hunga Ha'apai burst 65kms north of Tonga's capital, Nuku'alofa on January 15.

Homes in Tonga were destroyed or covered in volcanic ash, while three people died after the eruption. The effects of the tsunami were felt around the globe on the coasts of Japan, America and even in the Hastings.

Jason Harper, from Harpers Oysters in the Camden Haven, said a tidal surge was strong enough to snap lines and pull oyster racks out of the water over the weekend.

"We had a look on Monday morning and it wasn't good. We had a lot of broken lines, snapped in half which hold our infrastructure," he said.

"There were broken rafts and it pulled a couple of racks out of the water. We haven't lost oysters but there was a lot of damage to infrastructure, obviously it had a lot of force behind it.

"It was a bit of a surprise because the warning watch was taken off this area and it was quite a way away.

"I think this will cost us about $7000 to $10,000 to replace materials that were dislodged It seem like it's been one thing after another at the moment."

Ewan Bale, from Port Pearler Oysters, said it was a similar situation for oyster farmers in Port Macquarie.

"We were affected and we had some rafts displaced. Everyone had varying levels of damage and it has taken a good day and a half to repair," he said.

"Initially I saw the tsunami warning and just disregarded it being so far away. But considering how the surge turn the corners of the river and did what it did, you have to respect the power of mother nature.

"The past two years we have had some crazy weather events. We had that cyclone surge in late 2019 and the one-in-100 flood in March and now this one.

"It's been a freakish series of events on the river and you just have to roll with it because it's not a sheltered environment.

"I know quite a few people were fixing infrastructure during the week, but I think it could have been worse if it arrived on a higher tide."