A Queensland tourism operator says the next big high tide will be enough to cause three houses on his resort hit by a cyclone to completely collapse.

Three buildings at a central Queensland island resort are expected to collapse at the next high tide after being battered by swells whipped up by ex-tropical cyclone Dylan.

Great Keppel Island Hideaway co-owner Sean Appleton says his staff have all but given up trying to save the three houses at the resort, off Rockhampton.

The 250-bed resort has already lost three decks since Dylan crossed the north Queensland coast early on Friday.

Mr Appleton says staff had used a tonne of sand to protect the property in recent days, but to no avail.

The swell was just too big, with one tide eroding up to 10 metres of beachfront, he said.

“It was no greater than we anticipated, but it was greater than we could stop,” he told AAP.

“We had no hope.”

Mr Appleton said the next major high tide, expected at about 10am (AEST) would signal the end for his three accommodation buildings.

“We’re in the middle of pulling down what we can now,” he said on Friday afternoon.

“The fronts are gone, they’re on a horrible lean and tomorrow morning, what we can’t get down, will go to the beach.”

Mr Appleton said the damage might have been avoided if an application made to Rockhampton Regional Council two years ago to have a rock wall erected to protect the resort hadn’t been rejected.

It would have saved about 150 metres of beachfront on Great Keppel Island, he said.

Mr Appleton said there was now a risk of saltwater spreading behind the resort and into freshwater areas on the island.

“That’ll just be a disaster for the whole place,” he said.

Mr Appleton estimated a current damage bill of $300,000, but said that would likely blow out further depending on how much damage further tides created.