In hot water and loving it

New Zealand’s Polynesian Spa is an internationally renowned thermal resort that has become one of the region’s most successful businesses. Alfa Laval has played a significant part in this.

DATE 2023-11-28 AUTHOR Annette Taylor

AFTER SUCCESSFULLY COMPLETING a multimillion-dollar redevelopment of Polynesian Spa in Rotorua, New Zealand, Managing Director Martin Lobb says he’s looking forward to the day-to-day running of the family business.

“As with any company, there are various projects to be involved in,” he says. “Innovating and building is nice, but then it’s equally nice to settle down to run what you’ve created, to make sure it works and is promoted well. I’m looking forward to that this year.”

Nestled on the shores of Lake Rotorua, Polynesian Spa is New Zealand’s leading international spa. It has provided thermal bathing to millions of visitors since it opened more than 125 years ago. Today it offers 26 hot mineral pools filled with water from two natural springs. The complex also features a large freshwater family pool, the Hot Springs café and the Spa Essentials gift shop. Also within the complex is the Lake Spa Retreat, offering a range of hydro and dry relaxation spa therapies that make use of Rotorua thermal mud, New Zealand Manuka honey and other natural ingredients to relax and soothe bathers.

Voted one of the world’s top 10 spas by the Conde Nast Traveller magazine from 2004 to 2007, Polynesian Spa attracts more international visitors than any other spa in New Zealand; about 60 percent of its customers come from overseas.

Four years ago the spa management decided to create capacity in the form of 13 new private rock pools and three terraced adult pools. “The private pools were 30 years old, and you get to a stage where you can’t continue to repair them,” Lobb says. “Also we needed extra capacity in the public bathing pools, especially at peak times.”

Alfa Laval was an important part of the process. The spa uses the company’s plate heat exchangers to transfer the heat from the geothermal bore to the various pools in the complex.

Geothermal bores have long been used in Rotorua for heating domestic water, space heating and swimming pools. Such was the extent of past draw-off that by the 1980s it was apparent the city’s world-famous geysers and other thermal attractions were suffering, and in 1986 strict controls on such bores were implemented.
The geothermal fields have now recovered, but restrictions on bores remain in place. Businesses such as Polynesian Spa are permitted to draw only a limited amount each year and must make optimal use of the resource allocated to them.

“Like all business these days, you have to think about sustainability, the environment and the best use of a limited resource,” says Lobb. “Alfa Laval was able to help us achieve a solution because their technology is so efficient. What it came down to was, if we wanted more pools, we had to think of smarter ways of doing it.”

Polynesian Spa has used Alfa Laval technology for about 30 years, Lobb says. “In the past we’ve used their heat exchangers for heating buildings and domestic water, but in this latest plan we use them also for heating pool water and sanitizing,” he says. “And along the way we’ve built a good working relationship with them. Because we’re not engineers, we have to work with the experts who can assist us.”

LOBB SAYS HE IS DELIGHTED with the results of the NZD 4 million (USD 3 million) redevelopment, which also allows for future growth.

“While tourism numbers into New Zealand have slowed, in the next two years Rotorua’s airport is going international, linking us directly with Australia,” he says. “We expect an influx of visitors, and that’s pretty exciting because Australia is New Zealand’s biggest market.”

Currently, however, Polynesian Spa’s single biggest market is Korea, whose people have a real affinity for Rotorua, Lobb says. “They have a strong bathing culture; they love it and think Polynesian Spa is the best product in New Zealand.”

The spa’s reputation dates back to 1878, when a Catholic priest who bathed regularly in the hot mineral pools noticed his arthritis was greatly alleviated. While the local Maori people had known of the hot springs well before then, the first official bathing pool was opened in 1882, and the hot springs were run by the New Zealand government until 1972. In what was one of the first state sell-offs (a process that would accelerate greatly in the 1980s), the government decided it shouldn’t be in the business of running hot pools, and sold the hot springs to Martin Lobb’s parents.

“It was very different back then,” he reflects. “It was run down and losing money. It offered segregated, nude bathing,with attendants in white coats standing by – stuffy and very old Victorian-style bathing. One of the first things Mum and Dad did was to get away from the staid old bathhouse image. So they built some new pools, and filled the place up with plants and strong Polynesian images. And called it Polynesian Pools.”

It was Lobb who first turned to Alfa Laval for water-temperature management. Before that, much simpler and less efficient shell and tube heat exchangers were used.

ALONG WITH HIS TWO SIBLINGS, Lobb started to help with the business while still at school. He trained as an accountant, and in 1986, when his parents retired, he joined the family business. He has been there ever since.

It has been a rewarding experience, Lobb says. “Tourism is such a neat industry to be in,” he says. “You’re not dealing with nuts and bolts or cans of paint, but with people and their entertainment and pleasure. There’s huge satisfaction in providing products or services that people actually love.”

The facility has progressively been developed over the past three decades. “That’s because consumer needs and the market mix have changed.” Lobb says. “We get people from all over the world who visit spas in Italy, Hungary, America and Asia and expect an international-quality product when they come here. And we think we’re offering that.”

Late last year Lobb and his wife, Barbara, the spa’s retail manager, visited four of the world’s top thermal pools in Europe.

“We wanted to see how we measured up to international standards,” he says.

“I thought we measured up pretty well, actually. They’re dealing in bigger numbers, but it’s just economies of scale. We have this fabulous mineral water here, and it’s possibly a touch hotter and clearer.”

Providing bathing water to clients can be tricky at times. “We’re lucky we can tap into this wonderful resource, but mineral water is mineral water,” Lobb explains. “It’s not filtered, crystal clear and chlorinated like your pool at home. Some people come here and find the water is cloudy, and it can change colour with the atmospherics. And they say ‘well, what’s this?’ The springs are natural; you can’t tamper with them too much.”

The key now is to match the excellent facilities with equally excellent service. “We’ve got a good team of about 80 staff, and we believe in training,” Lobb says. “At the moment it’s hard to get good people because there’s not a huge pool of the right people; everyone is struggling for staff. But we get them, and we keep them.”

As to the future, he says there’s always something on the drawing board. “It’s the nature of the company,” Lobb says. “One of our jobs is to make sure that when people come to Rotorua – and there’s about 150 different things they can do – that they come here. That’s it. You can’t come to Rotorua and miss out on a hot mineral swim. That is the quintessential Rotorua.”

The next challenge is to understand the new plant heating the pools. “It’s very complex, like the engine room of a ship,” Lobb says. “We have to learn how it works and its nuances.”

It’s a challenge, he says, that he’s looking forward to.

Always evolving: heat exchangers

Plate heat exchangers, such as those used at Polynesian Spa, transfer heat efficiently from one fluid to another in a controlled fashion.

At the spa the primary heat source is superheated steam from a bore that taps into the geothermal field underlying Rotorua. The Alfa Laval plate heat exchangers transfer heat from this to a freshwater loop, which then transports the heat to another set of heat exchangers. These supply both fresh and mineral waters of varying temperatures to the various pools of the complex, which are each kept at a specific temperature, mostly ranging from 36 to 42 degrees Celsius, with a large chlorinated freshwater family spa pool at 33 degrees Celsius. The geothermal source is also employed, via the heat exchangers, to provide underfloor heating, domestic hot water and space heating.

Alfa Laval quality coordinator Marian Ioan says Alfa Laval is at the forefront of heat exchange technology. “We’ve pushed hard with new ideas,” he says. “Plate heat exchangers are flexible technology and are always evolving, with new plate and gasket designs almost every year. If increased capacity is required, it’s easy to add more plates.”

Because of the restrictions on use of the geothermal resource, it is essential to capture as much of the available free heat as possible, Marian says. “The plate heat exchangers can offer heat transfer coefficients that are four and a half times higher than those of a shell and tube exchanger,” he says.

The company provides most of the heat exchangers for Rotorua’s motels, but Polynesian Spa is its biggest customer in the city, with 16 units on site. Martin Lobb, the spa’s managing director, says the plant design allows the spa to reheat, filter and sanitize the thermal pool water, thus reducing the use of a scarce resource. “Our waste pool water has all the contaminants removed before it is discharged to Lake Rotorua under a discharge permit,” he says.