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Swimmers like St. Paul’s moss-based pool-cleaning system


St. Paul’s experiment with using a moss-based system to clean the water in two city pools is paying dividends: Officials say word of the new system has attracted hundreds of new swimmers who want to check it out.

The system, called sphagnum moss-based water treatment, has been installed in the Highland Park pool and the new Great River Water Park. It uses moss — along with the state-required chemical system, which still must be used — to treat the water.

Here’s how they say it works:

The pilot project involved installing a series of canisters housing the water conditioning sphagnum moss that work along with state-mandated chemical systems to ensure pools are safe for large general public usage. The system uses natural moss to control the growth of microorganisms such as bacteria, algae and other waterborne agents and by reducing metals and other deleterious elements. 

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City officials report that they have used fewer chemicals, see less corrosion in pipes, find fewer maintenance issues and say “the majority of those surveyed at Highland this summer report very clear water with no taste, clear vision in the water and smooth-feeling skin before and after swimming.”

A city report says:

“All summer, people of all ages who have swum here for many years have asked us, ‘What have you done to the water? It feels so good.’ ” said Lynn Waldorf, supervisor of aquatics. “We all learned a lot about how the science of natural water conditioning really works and witnessed first hand its impact on our pool users, staff and equipment. We are thankful for being involved and look forward to the day when the use of moss in public pools is the standard rather than the exception.”

“It’s a completely different pool,” said 19-year-old Mary Schmidt, a regular weekly visitor to the pool as a summer nanny. “My eyes and the kid’s eyes didn’t get red, the water didn’t smell of chlorine and it was a lot softer feeling in general. I love it.”

The city conducted the pilot program with Creative Water Solutions of Plymouth.