Gym swimming pools are set to increase their blue footprint

Siphelele Nqolobe, pool operations technician at the Mitchells Plain Virgin Active Gym takes great pride in keeping the facility’s indoor swimming pool clean. He strives to ensure that its crystal-clear water perfectly complements the large posters of white beaches, granite boulders, and the crystal-clear seawater at popular Cape Town beaches framing the pool. The many positive reviews and direct comments from gym users on the pool water quality make his early morning commute and the late hours he often keeps all worthwhile.

Recent reviews from gym members on the website read: 

‘The pool is immaculate and well worth the fee alone’: Conner C

‘I make use of the swimming pool on a weekly basis’: Chantal De W

In recent months, the 25-year-old has added another positive experience to his growing skills list: in December 2023 he participated in the full-scale testing of a South African research innovation, the VulAmanz Backwash Water Recovery filter system. It recovered 100% of the backwash-water used to clean the four standard sand filters at the pool. In the process, the gym saved up to 7 500 litres of water per week that previously would have quite literally been sent down the drain and into the municipal sewage system. During the month testing period, all backwash water was recovered, cleaned, and returned to the pool without wasting a drop. It meant that Siphelele oversaw the saving of 30 000 litres of municipal water that would have been required to top-up the pool. 

The only addition made to the gym’s existing pool maintenance system was to consciously NOT open the valve that would normally have drained the backwash-water to the sewer. Al filthy backwash-water was collected in a 5000 litre storage tank from where a water level controlled submersible pump sent the dirty water to the 18 Filter Element BWR filter system. The robust filter elements are made from tightly woven polyester microfiltration fabric manufactured in the VulAmanz factory in Stellenbosch. With all suspended solids removed, the water flows under gravity back into the pool from which it originated. And so the process of reclaiming water continues. 

Ngolobe was surprised that the new technological ‘add-on’ did not require many changes to his existing pool maintenance programme, other than having to clean the filter elements once every two months using a giant bottle brush. He knows that the research team is also working on an automated system that could further save time. If the membrane is not punctured by accident or deliberately, the robust filter elements have a lifespan of at least 5 years, and do not have to be replaced at all.

He has noticed that the chemical balance in the pool water remained well within the required range for longer. The gym is therefore saving on pool chemicals as well. Ngolobe understands that this is because the recovered water still contains much dissolved chlorine and other pool chemicals. By recycling it, chlorine-laden water is no longer dumped into the sewage system to potentially influence the balance of municipal treatment plants and disrupt the finely balanced environment. 

It is with pride that he regularly looks at the ever-accumulating reading on the water flow meter that keeps track of the efficiency of the VulAmanz Backwash Water Recovery filter and of the actual volume of water returned to the pool. The 7500 litres of water per week that the gym saved during December 2023 adds up to an annual saving of about 350 000 litres – from only one gym pool.  

He has done the math. If a VulAmanz Backwash Water Recovery filter was to be fitted to each of the 14 commercial gyms operating as part of the same franchise in the greater Cape Town area, a total volume of around 5 million litres of water could be recovered each year in the Western Cape alone. This will allow the franchise group to markedly improve its blue footprint, and to head the Western Cape Government’s call on its 110% Green webpage for enterprises to reduce their water consumption, use water efficiently, minimise water waste and augment water supplies. Using the VulAmanz Backwash Water Recovery filter ticks all these boxes.