Dive into a natural swimming pool: A backyard oasis
Do you love to swim, but hate the smell — and eye burn, hair damage, skin dryness and swimsuit fading — you get every time you jump into a chlorinated pool?
A natural swimming pool might just be the answer for you.
A natural swimming pool offers a slice of suburban paradise
A natural swimming pool (NSP) is an alternative to the typical chemically-treated swimming pool concept. Like their commonplace counterparts, the natural pools are specifically constructed to contain water — meaning they don’t have muddy or sandy bottoms or sides. In fact, some pools can look very much like the gunite-bottomed swimming holes Americans have come to know and love over the decades, while others have much more of a pond or creek vibe.
But what’s really different is how these pools clean and filter themselves. Instead of the water being disinfected and sterilized by chemicals (such as chlorine), it is instead clarified and cleaned by hydroponically-rooted plants that feed on the nutrients in the water — made possible by a pump feeding a natural filtration system.
The plants are kept separate from the swimming area — in what’s termed a regeneration zone — through which the water from the pool flows, nourishing the plant life.
More technically, “A natural swimming pool is a balanced wetlands ecosystem based on the principles of limnology, hydraulics, hydroponics, and modern pool construction methods,” notes BioNova, who brought natural swimming pool construction to the US in 2008.
So how, exactly, does that explain the way a natural swimming pool will stay clean? “The water is treated biologically. There are no chemicals used, nor are there any devices used that would disinfect or sterilize the water,” says BioNova.
“The movement of the water through the biological filter, the action of the aerobic and anaerobic bacteria in the filter and regeneration zone, as well as the plants feeding hydroponically on the water, is how the water is cleaned.”
The Biotop Natural Pool Company in Germany, one of the first to build these unique sustainable pools, notes that the ratio of the swimming zone to the regeneration zone is generally 1:1, and the depth is at least two meters [6-1/2 feet] in the swimming area.
“This is the basis for a functioning pool. If more technology is used, the regeneration area can be smaller with less depth.” They further note that their pools are “inoculated with zooplankton (water fleas, rotifers, paramecia), which play an important role in the cleaning process. All it takes is a little bit of patience until the pool finds its balance.”
Patience, and a little TLC. BioNova says that some aspects of maintenance are the same as for a traditional chemical pool. “We need to periodically empty and clean skimmer baskets, empty and clean pump baskets, vacuum the pool and clean the filter. Water garden maintenance is also necessary — removing unwanted plants, trimming and maintaining existing plants, and cutting them back at the end of the season.”
The first NSPs were built in the early 1980s in Austria, and by the mid-1980s, companies in Austria and Germany began creating natural pools for homeowners. Slowly, the market spread throughout Europe — where they’re often called “natural swimming ponds” — and the concept first made a splash in the US when the New York Times wrote about the pools in 2007. It’s taken a few years, but now the trend is really heating up stateside.
America’s heat, though, does change the business a bit, since it’s actually hotter in many states than it typically is in the regions around Berlin and Vienna.
Mick Hilleary, President and Designer at Kansas-based Total Habitat explains how the pool construction and systems need to be adapted to suit to different environments. “Plants alone, even in expansive zones, don’t provide the cleaning horsepower needed for the warmer climate we have here in the USA,” he says. “We love water plants, but technically, it’s the beneficial bacteria that cleans the water — the more living space you give them, and draw water through, the more nasty stuff they consume.”
Even with extra filtration power needed, natural swimming pools are still a very eco-friendly and sustainable option. They only need to be filled once, don’t leach chemicals into the environment (or into you), and use power efficiently.
And, perhaps be best of all, these man-made “swimming ponds” offer homeowners a uniquely tranquil experience. As Peter Petrich, owner of Biotop, says of his creations, “A natural pool is an image of nature that one can have in one’s own garden, a biotope that exists in the lively cycle and interplay of plants and animals.”