The bottom of The Rock pool is getting a fresh coat of blue paint, and there are parts of the park's waterslides, built into the ever-shifting green slopes of Jamberoo, to tighten against leaks.

A packed schedule of maintenance and repairs is an annual prelude to the hordes that will erupt through the gates come Spring.

By opening day, September 23, the air will almost crackle with the collective abandon of thousands of visitors. "An electric environment" - is how one employee describes it.

There to oversee it all is the park's founder, Jim Eddy.

Jim is banking on a big season in order to finance the next step in the park's 14-year-old master plan: a new ride.

The 440-metre rapid river will wrap around existing attractions the Funnel Web, Perfect Storm and Banjo's Billabong, jostling the tube-buoyant rider down a descent of four metres from start to finish.

The ride, which comes with a price tag of $10-12 million, promises a different experience to the park's existing Rapid River, a gentle, meandering affair powered by a single wave machine set on low.

"It will have three other wave machines - dialled up so we can get a lot more activity," Jim said.

"It will simulate a more exciting rapid ride."

Now 75, Jim has never stopped chasing his next big thrill.

He recently returned from a trip to Dubai to see the world's newest version of the rapid ride in action.

Long-time colleagues wondered if Jim's retirement could be nearing in 2016, when he bought a waterfront Wollongong site and helped make it into a landmark restaurant, Steamers Bar and Grill. But the restaurant became the domain of his life partner, Caroline Brinsmead, a restaurateur, while Jim again set his gaze southward to the Jamberoo hills.

Those closest describe him as a visionary with a high risk threshold and an unparalleled business acumen.

"He's got a knack for knowing what's going to work. It's a bit uncanny," said Ms Brinsmead, who says Jim can be found walking the park's grounds during Summer, "looking, feeling, asking, 'what the customers saying?'."

"But there's also a lot of heartache; a lot of debt. ... a lot of sleepless nights. It all revolves around the weather."

The park's long-serving chief financial officer, Jon Bailey, says Jim's superpower is that he'll "have a go at anything".

"He's not scared of borrowing the money with an idea in mind, and putting that idea into place," he said.

"He does his numbers, he does his checks. He goes around the world looking at all these rides. I've been with Jim a long time and so far, everything's worked."

Another of Jim's businesses, the Belmore All-Suite Hotel in Wollongong, was reportedly performing nicely, with a reliably high occupancy rate making it sure business bet, when Jim sold it in 2019, having found the operation boring.

There is no such problem at Jamberoo, where each season brings a new wave of financial uncertainty. With such large sums of money involved, the years spent introducing a new ride are the riskiest of all. The stakes are only ever high.

"Most of this is pioneering stuff and you've got to work it out as you go, so you've got to have a very high contingency factor," Jim said.

"Every time we add something new, we're on the brink."

"You've got to be really careful. You're under a lot of pressure to get the planning process right ... otherwise costs will run out to an exorbitant amount."

The park was dairy country, owned by the East family, of Easts Beach fame, when Jim pooled funds with his mother, sister, brother-in-law Robert and Robert's brother, Peter, to buy the land in 1979, so Robert could be a dairy farmer.

Soon after, the NSW Government opted to share the Illawarra's milk quota with the North Coast, slashing the farm's income by 18 per cent.

"We had a milk quota problem, which led us to a debt repayment problem," said Jim, who was a surveyor with BHP and a real estate broker before he became a theme park owner.

The group pivoted to grass skiing, importing 10 pairs of skis from Italy, with good results.

There were 22 per cent interest rates to contend with and - always - the weather.

When drought burnt the grass off the ground in 1982, turning it and the grass skiing business to dust, Jim again pivoted, this time to the park's first waterslide.

"I found it on the Gold Coast. It was a roaring success," he said.

"It was accidental progress."

Many theme parks are built on denuded land, their attractions laid bare on baking concrete slabs.

But the lay of the land at Jamberoo allows for a sense of discovery, with multi-million dollar rides nestled sometimes hidden in 100 acres of green hills. There have been landslides here; the land is always slightly slipping which requires funds and infrastructure to manage.

When it comes to tight times, COVID lockdown doesn't warrant a mention from Jim.

The years 1989 and 1990 were two of the wettest in the park's history.

"In 1989, it rained every weekend for 23 weekends in a row. Golf courses were going out of business."

But the park had already survived its darkest hour by then.

In the winter of 1984, a 20-year-old Fairfield West man, Warren Grant Drewett, died after coming off park's famous toboggan ride at high speed.

He was impaled on a fence post that had been brought down in an earlier landslip..

Jim was there that day during what became an extended emergency response.

Drewett died while undergoing surgery in hospital.

Park officials of the day told the Mercury that Drewett had earlier been warned eight times to slow down and had complied with a direction to leave the park, only to slip back inside.

"It devastated everybody involved," Jim said.

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Him and his business partners all struggled with their commitment to the business.

"And I struggled with it too, because I was heavily involved in it at the time," he said.

"Everyone lost their spirit for the business at that time, even myself."

But the tragedy ended up reshaping the park and galvanising Jim to it for life.

He threw himself into a tour of American theme parks, with a new driving mantra of "never again".

"I met with number of major operators over there - Disney, Six Flags - and talked to them about their experience of people losing their life in their park," he said.

"And it sort of opened my eyes up. You bring a lot of people together; there's safety risks.

"The most important thing that came out of it for me, the experience I got from those people is: you've got to do everything possible to avoid it.

"And when you think you've done enough, you've got to start again and do it again and keep on. It's something you work on the whole time.

"From there we took a lot more of a strategic approach to the business and how we took it forward.

"It led me to this conclusion that we had to do a lot more than we were doing to stop that from happening again.

"That put us on the pathway that we've been on ever since."

Jim bought out his co-financiers.

His own three children have been among the thousands of workers the park has employed, with the current workforce at more than 300 seasonal attendants plus 30 permanent, year-round workers.

While the rising cost of public liability insurance looms large as a current concern, Jim says it is power - the cost of it and growing uncertainty surrounding its supply - that poses the single greatest threat to the park's future.

A favourable five year electricity contract expires in December next year balloon from $500,000 to $1 million - "serious money" - as Jim puts it.

Ever the out-of-the-box thinker, the problem has turned Jim's thoughts to a controversial place - nuclear.

He ultimately knows it cannot happen; he says he has no plans to lobby government on the issue.

But he was serious enough about it to have had "discussions" with scientists at the Australian Nuclear Science and Technology Organisations nuclear reactor at Lucas Heights. Those conversations covered the cost of powering the park with a type of modular reactor.

"We would be serious [about it] if we were allowed to be serious," he said.

"The big thing is the waste. The waste lasts 30,000 years ... but from what I've read, that's overcomable."

"Without that there's no other forms of mass generation that will fulfil the needs of our state. In the absence of that we've got to come up with a solution, and got to come up with it quickly. I'ts just disgraceful that it's not better planned."

Despite the park's rising costs, Jim's strategy for the 2023/24 season includes a price freeze, aimed at encouraging maximum numbers through the gates.

It seems a small gamble, in this place built on thrill, by this man seemingly made for risk.

"Time heals all sorts of wounds," Jim said. "Ever since Captain Cook arrived, property's been going up and if you can stay the distance, you can last long enough, you'll come out of it. But if you can't, you'll definitely go down."

With thanks to Wollongong Library's Local Studies section.

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