Another problem is the nearby Tuwhakino Stream, which regularly floods the complex after heavy rain. The resulting closures further reduce revenue and make organised groups reluctant to visit - even though the pools are just half an hour from the Bay of Islands' tourist hotspots, where wet-weather activities are in short supply.
Now, however, the Parahirahi C1 Trust has come up with a plan to turn the oily-rag business into a "thriving, outward-looking, opportunity-creating economic venture" by upgrading the facilities and building a floodwall.
The redevelopment would allow the entry fee to be raised to $12 for tourists - the local price would remain $4 - and create three full-time jobs.
In a report to the Far North District Council on Wednesday, the trustees said they had self-funded the project so far and were now raising money for consents. As the building stage approached they would apply to organisations such as the Lottery Grants Board and the ASB Community Trust, as well as government agencies and investors.
Councillors agreed to the trust's request for a 33-year peppercorn lease of the land, which is part of the council-administered Ngawha Springs Domain Reserve. The trustees said the lease was necessary for the redevelopment to go ahead.
Chairman Te Tuhi Robust welcomed the council's decision, saying it provided a way forward for the trust and would boost employment and economic development in the area.
Among the regulars at the pools yesterday was Renata Tihore of Ngawha, who swore by the water's healing properties but said the complex needed a decent ablution block.
"I've seen the plans and I like it, I tautoko (support) it."
Tukaki Waititi, of Kaikohe, said the complex could use a tidy-up, as long as it was not turned into a Rotorua-style pool with the goodness filtered out of the water.
"The reputation is really about the healing waters, it's not about the looks," he said.
Clive Stone, who had driven from Oakura for a soak, said he backed anything that advanced local iwi.
"If it improves their position, go hard. I'm all for it."
The reserve is Crown land and could be returned under the Treaty of Waitangi. However, Crown policy is that any return be part of a wider settlement with Ngapuhi. That could still be years away.
The Ngawha geothermal field is New Zealand's largest after the Central Plateau. Is also feeds Ginns Ngawha Spa, a privately owned hot pool complex, and Top Energy's Ngawha power station.
