Nearly four billion litres of water are wasted though paddling pool use during hot weekends, so environmentally-conscious parents may be tempted to reuse the same water over the course of several days.
But Ralph Riley, vice chair of the Pool Water Treatment Advisory Group and Dr Lisa Ackerley, a chartered environmental health practitioner, both advise parents to use fresh water in your paddling pool every day you have it out, to reduce the risk of a child picking up an infection.
If you’re concerned about saving water, the best thing to do is save paddling pools for a special treat.
Unlike professionally-run swimming pools, which have filter systems and are treated with a chlorine-based disinfectant treatment, the majority of at-home paddling pools will be filled with water from the mains.
Although this water does have a certain amount of disinfectant in it – due to the fact household water is centrally treated to make it safe – this small amount will diminish during the day, as disinfectant is broken down by the sun’s UV rays.
“Paddling pools can quickly become a bacterial soup with bacteria and viruses from children and debris picked up on feet before going into the pool,” says Dr Ackerley, who runs the website The Hygiene Doctor.
“It’s important to change the paddling pool water every day – drain it and let it dry at the end of the day and use an anti-bacterial spray to kill any germs so it is safe to use the next day.”
Covering a filled paddling poll overnight might protect the water from some insects, but Riley thinks infections from other people should be parents’ main priority. Infections such as athlete’s foot, verrucas and stomach bugs can fester in water over time and pass from person to person.
“A paddling pool in the garden is no different to a bath at home,” he says. “If one kid has a bath after the other one, because you’re one family, it’s not a big problem. But if you invite all the neighbour’s kids in, that’s a different matter. When you’ve got different kids from different families, you don’t share the same bugs, and therefore you need to be more careful.”
Val Curtis, from the London School of Hygiene and Tropical Medicine, says there are some circumstances where it might be wise to change paddling pool water more than once per day.
“Common sense would say that water should be changed and a pool cleaned out if a child has an accident. Also if mosquitoes can be seen breeding in the water [with the appearance of] tiny swimming larvae,” she tells HuffPost UK.
Of course, one of the benefits of paddling pool water being disinfectant-free is that it can be reused to water your garden. So if the kids do insist on filling up a pool, be sure to reuse anything left after all the splashing to avoid wasting the water.