Page 61

STA POOL PLANT – CLOUDY WATER

Cloudy Water In this issue, the STA’s Pool Plant Consultant Robbie Phillips looks at how to tackle the issue of cloudy water in outdoor swimming pools that are used by the public

W

ith summer fast-approaching, operators of outdoor swimming pools will be gearing up for a busy season ahead (weather permitting of course), and one of the most common problems we see with these type of facilities is cloudy water. This is primarily caused as a result of heavy bather loads and ensuing poor maintenance. If ignored or allowed to develop to specific levels, cloudy or milky water presents a serious hazard to bathers; especially for children who cannot be seen effectively in a crowded pool. Filter sand in the pool also poses a serious health risk, not only from clarity, but from diseases being able to spread easily as the filters cannot trap these microscopic particles. Ultimately, pool operators have a legal responsibility to safeguard patrons; the pool should be closed if the clarity of the water is not sufficient to see the bottom of the pool. In the US for example, statistics show cloudy water significantly contributes to the number of drowning deaths every year. The importance of managing and monitoring cloudy water therefore cannot be underestimated – it is a vital aspect of aquatic safety – and not just for the pool operator, but for swimming teachers and lifeguards as well.

CHECKPOINTS Cloudy pool water is caused by a number of factors such as faulty filtration, improper chemical concentration, and environment i.e. bather loads. Therefore, when pool water appears cloudy or milky, and a fine white precipitate settles after peak use periods, operators should be trained to check the following items (this advice applies equally

If ignored or allowed to develop to specific levels, cloudy or milky water presents a serious hazard to bathers; especially for children who cannot be seen effectively in a crowded pool” www.swimmingpoolnews.co.uk 59_SPN_April_18_STA.indd 59

to indoor pools that face heavy bather loads in peak seasons): Turnover Rate: Make sure that the normal safe flow rate is being maintained, and that an obstruction or pump impeller damage due to cavitation is not restricting the amount of water moving through the filters. Filter Valves: Make sure that all valves are open or in the correct position to allow water to move correctly and effectively through the filters. Broken Laterals: Check the bottom of the swimming pool first thing in the morning before the water has been agitated; look for regular deposits of filter media sand near the return inlets. Damage to the underdrains compromises filtration and hygiene within the pool. Fines: If filters are not backwashed properly and for an adequate amount of time, fine particles start to work their way down into the filter bed. Eventually fines are carried into the laterals and back into the pool. A similar process can happen with regenerative filters where if the process is not correct or septa are damaged, the fine celite type media can return to the pool. Channelling And Mudball Formation: Any mudballs and channels which form on the An example of what can happen with poor backwashing

Sand from a filter deposited on the pool floor

sand bed should be destroyed. Mudball formation is caused by calcium scale, organic debris, detergents, oils, and bather waste products. These oily products reduce sanitiser effectiveness, promote bacterial growth, and cloud water. In addition to forming scum lines at the water surface, they may also clog the filter. Filters Not Properly Sized: Make sure that the filters are properly sized. If water is allowed to flow through the media at a rate higher than that recommended by the manufacturer, much of the debris will pass right through without being removed. High TDS: Use a TDS meter to determine the level of total dissolved solids. Sweeping And Vacuuming: The pool tank should be swept or vacuumed daily. For Outdoor Pools, High Cyanuric Acid levels: Do not use cyanuric acid or chlorinated isocyanurates in indoor pools, or in outdoor pools and spas with extremely high organic loading problems. If cyanurates are used to prevent loss of chlorine and dissipation into the air due to exposure to ultraviolet light, use in moderation. (NOTE: In all pools controlled dilution is essential.)

PROFESSIONAL TRAINING Our final piece of advice, before attempting any of the aforementioned steps, is to make sure staff are properly trained in all areas of swimming pool and spa plant management. STA’s Level 3 Award in Pool Plant Operations qualification, which is now CIMSPA endorsed, covers all operators need to ensure safe, clear and hygienic water practices in pools, spas and interactive play features. STA 01922 645097 www.sta.co.uk

A TOP TIP FOR TESTING FILTRATION Perform a settling test to determine the make-up of the filter bed. Take a large glass jar (like a mayonnaise jar) and fill it with 2 cups of water. Add 1 cup of media from your filter. Add 1 teaspoon of dishwasher detergent or Calgon water softener. Replace the jar lid and shake. Allow the solution to settle overnight. The sample should settle into a layer of sand with water on top. If instead, it settles into layers with the sand on the bottom, silty material above the sand layer, and an organic layer on top, replace the filter media in the tanks.

SPN April 2018 59 23/03/2018 16:18

SPN (Swimming Pool News) April 2018  

Informing the pool and spa industry since 1959. Covering the UK's wet leisure market, SPN (Swimming Pool News) is the UK's longest running a...

SPN (Swimming Pool News) April 2018  

Informing the pool and spa industry since 1959. Covering the UK's wet leisure market, SPN (Swimming Pool News) is the UK's longest running a...