Water Hazard
Managing Aquatic Risk
By Daniel Margolis
Jim Tanner, director of aquatic and industrial sales at a manufacturer of water filtration and chemical feed systems, recently returned from a trip to Europe, during which he investigated new approaches to water purification being employed in the region.
"In Europe, they have a much more stringent water quality standard than we do in North America," he said. "They use much better filtration methods; bigger filters, slower rates into those filters and they do some dilution of the water."
Any pool is going to lose some amount of water as it's used, either through evaporation or runoff. Pools make up for this using an automatic makeup water valve, bringing in standard drinking water. "Most people think 'Drinking water's safe because I drink it.' Well in reality, the distribution systems for drinking water, depending on how close you are to the water plant, there are small amounts of chlorine in them, disinfecting the water," Tanner said. "So you get a lot of biofilm in the distribution."
Biofilm is basically microorganisms encapsulated within a protective shell. To combat this, the practice in Europe has become to inject a small amount of chlorine dioxide into the makeup water as it's coming into the pool. Tanner said, "You breakup these biofilms before they get into the pool; separate them so the chlorine can attack it and get the bacteria and viruses before they hit the water."
Tanner described how chlorination has evolved in Europe as well. "What you see in the States is a lot of feeding or salting the pool to produce chlorine on site," he said. "In Europe, they developed a way to produce the chlorine in batch tanks on site and then pump in fresh as needed, almost like they have a little chemical plant right there in the facility."
While Tanner doesn't feel there's any particular "standard bearer" in combating RWIs, he does feel that as these contemporary approaches come into practice in the United States, aquatic recreation will become increasingly free from RWIs. Now, if we can just keep the dirty diapers out of the pool.
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