UV disinfection keeps spring water pure

Nirvana Spa in Berkshire is one of the UK’s most prestigious spa facilities, frequented by elite athletes and celebrities.

The facility has a reputation for using crystal clear natural mineral water drawn from the same pristine source 700 feet beneath the spa.

To maintain the purity of the water within each of its nine pools, the spa is using the latest ultraviolet (UV) disinfection systems from Slough-based Hanovia Ltd.

The spa has a broad range of pools, including Roman and surf rooms, a plunge pool, fitness pool, outside pool and hydrotherapy pool.

Each has a specifically-sized Hanovia UV system installed to treat the water, ensuring the high level of quality and disinfection required.

“The Celestial Floatation Pool, which is the UK’s largest hydrotherapy pool, is unusual because it contains salt imported from the Dead Sea,” commented Neil Phelps, Nirvana’s Maintenance Manager. “We match the specific gravity of the Dead Sea. The high salt concentration makes objects very buoyant in the water and floating in the pool is perfect for spinal alignment.

“Bathers in the warm, mineral-rich waters are removed from most external stimuli and a gentle current gives the sensation of floating in space. This provides both mental and physical benefits and many sports men and women, including international rugby players, skiers and rowers, use the pool to enhance performance and reduce injury time.”

“UV disinfection systems allow us to run the chlorine at the right levels and there is no way we would be able to achieve the level of water purity without them.

“As the water temperature is kept at a constant 35°C, which is higher than in leisure pools, there is an increased risk of infection from microorganisms such as bacteria and moulds which thrive in warm water.

“Microbiological control is a key aspect of the water quality. UV plays an important part in that control and bacteriological checks are carried out regularly,” added Neil.

“Hanovia’s UV systems enable us to achieve exemplary water quality in all of our pools. This, coupled with Hanovia’s outstanding aftersales service, gives us, the maintenance team, the reassurance to maintain the high level of water quality and disinfection required,” concluded Neil.



UV is highly effective at killing any bacteria, viruses or moulds in the water, including Cryptosporidium and its spores, which are chlorine-resistant.

This reduces problems associated with chlorine by-products such as chloramines, which are formed when free chlorine reacts with sweat or urine in pool water.

Trichloramines in particular are powerful irritants which are responsible for eye and respiratory complaints and the unpleasant ‘chlorine smell’ commonly associated with indoor pools. It also means the water is much clearer than that found in traditionally chlorinated pools.

Each Hanovia UV system installed at Nirvana Spa consists of a stainless steel chamber containing a medium pressure UV lamp housed in a special quartz sleeve to protect it from the pool water.

The chambers are carefully designed by Hanovia engineers using advanced flow calculation methods. This ensures maximum performance by making sure all the water flowing through the chambers receives the correct UV dose.

UV technology provides a cost-effective and low-maintenance alternative to other water treatment systems such as ozone.