Natural Swimming Pools Are Making a Ripple, But Are They For You?

When it comes to backyard swimming pools, that classic rectangular design with a deck, diving board or slide, and metal steps still holds appeal.

But natural pools that resemble swimming holes or ponds have gained increasing interest in recent years, according to landscape design professionals who have been turning out versions that mimic what Mother Nature fashions on her own: Interiors painted so water appears natural, clusters of rocks, waterfalls spilling over outcroppings, a diving boulder, water-loving plants, and water filtration systems that keep water healthy for the environment, and for people’s hair, skin, and swimsuits.

Landscape architect Marc Nissim of Harmony Design Group in Westfield, N.J., has constructed an increasing number of natural swimming pools over the past 15 years. “They now represent about 70 percent of my work,” he says.

A European Inspiration

The natural pool trend originated in Europe in the 1980s, but it has started to gain attention in this country in recent years. Early versions were fashioned to have more organic pond-like shapes, but, experts say, it’s a style that may not be for everyone.

Natural Pool
Natural pools are resembling conventional pool designs (Photo: Cipriano Landscape Design)

Chris Cipriano, who operates a landscape and swimming pool design firm in Mahwah, N.J., says that the pond-like designs can be an obstacle for some. While it’s a nice, natural look, he says, “for most of our clients who want a refined look, it may not appeal.”

That may be why the current crop of natural pools is resembling more conventional geometric pool designs. What differentiates these natural swimming pools from their traditional counterparts, however, is that the water is cleansed without using any chlorine.

Natural Filtration

Instead, the water goes through a natural filtration process. Beneficial bacteria and microorganisms, in conjunction with aquatic plants rooted in gravel and rocks, filter water in an adjacent pool, known as a “regeneration” zone. Then, it’s pumped back clean to the swimming pool, so it can be safe for swimming.

“It’s similar to how wetlands treat water more benignly than chemicals do,” says biologist Morgan Brown of Seattle’s Whole Water Systems, who experienced European natural swimming pool designs when he lived abroad.

Beyond the organic appeal, some see natural swimming pools as a way to prevent skin allergies or other issues associated with chlorinated water. But Sacramento, Calif.,-based landscape designer Michael Glassman cautions, “Be prepared to change your perspective about not swimming in crystal-clear water.” There may be minute algae particles, he says, which can give the water a greenish cast.

Pros and Cons

So, are you interested in natural swimming pools? Consider these additional pros and cons before wading in:

  • Design flexibility. Natural swimming pools can be integrated seamlessly into a site, and can be designed in any style—even a formal Grecian or Roman pool.
BioNova natural pools
Natural pools can be integrated seamlessly into a site. (Photo courtesy of BioNova® Natural Pools)
  • Ability to function in any climate. Alan Weene, who heads marketing for BioNova, the U.S. outpost of a German company that designs and installs natural swimming pools, says the company has constructed natural swimming pools in a range of climates around the globe.
  • Extra land requirement. They require a larger site because of the regeneration zone, says Nissim. “If you design a 700-square-foot pool, you need another pool of equal size for filtration. With community rules about setbacks and how much impervious surface you can have on a property, there are many yards where there isn’t enough space,” Nissim says.
  • Higher initial cost. Natural swimming pools cost more to build than conventional pools because of the need to construct two pools (the main swimming area and the filtration area), though per-square-foot construction costs are similar to conventional pools. They do typically cost less to operate because of the absence of chlorine and other chemicals, and the ability to use a smaller pump and less energy, Weene says.
  • Less-than-perfectly-clear water. The color of the water isn’t always “a crystal-blue, Windex color, yet it’s safe for swimming,” says BioNova’s Weene. Color varies, based on such factors as nutrient balance, temperature, and precipitation. Some algae and sediment always will be present, Weene says.

Featured image: Courtesy of BioNova® Natural Pools