What is a Natural Pool and is it Right for You?

Natural pools are the newest home swimming pool trend. They’re a chemical-free option —­­ ideal for people with chlorine sensitivities — that blends seamlessly into your landscaping.

What Is a Natural Pool?

Unlike saltwater and chlorine pools which use mechanical filters and store-bought chemicals, “natural pools function off having two sources of water,” explains Dan Bailey, president of WikiLawn. “(There’s) the pool itself and a nearby regeneration zone, typically built with a gravel filter or plants. Water flows between the sources, constantly being cleaned and recycled.”

Most people are used to swimming in the sparkling, clear water of a chemically-treated pool. Natural swimming pools work more like a pond or lake. Because they are manmade ecosystems and not true ponds, the plants can be kept separate from the swimming area. This protects the plants from damage while you swim, and it makes for a more pleasant swimming experience.

What Are the Pros and Cons of This Style of Pool?

Although they aren’t common in the U.S., natural swimming pools have a lot of advantages. Aesthetics are one of the main draws. “Natural pools can be any size or shape, which means they can be adapted to fit any space,” says Bailey. Some people design their natural pools to mimic genuine ponds or other bodies of water, but you can also get a more traditional pool design. The filter can even be hidden beneath other landscaping features, like a wooden pool deck.

Sustainability is another perk. By skipping the chemicals, natural pools don’t contribute to air or waterway pollution. Plus, they require far less pool maintenance.

The biggest downside of natural pools is their cost; they can be twice as expensive as a same-sized chlorine pool. (Chlorine pools usually start at around $30,000.) Bailey explains that “you’re essentially installing two pools, and the number of professionals who can even do it is far lower than traditional pools.” Because it’s such a specialized field, the initial cost can be higher than a traditional pool. However, you may save money on maintenance in the long run.

Another con: The style may not be allowed in your area. “Some county or HOA laws may prohibit it,” Bailey says. And while the water in a natural pool is safe for swimming, it isn’t as perfectly blue as a chemically-treated pool. The water can look similar, but there is a slight difference in clarity. Guests may not be accustomed to the appearance.

How Is the Water Filtered?

Any body of water will capture pieces of its environment. Dust, sand and leaves are just a few of the things that we don’t like to swim in, and without proper cleaning a pool can develop disease-causing microorganisms. In a traditional chlorine-style pool, these things are called contaminants, and they must be killed with the right dose of chemical sanitizers. In a natural pool, they’re used as nutrients for the wetland.

Natural pools offer the right environment for “beneficial bacteria, zooplankton, and phytoplankton to extract these nutrients,” according to BioNova Natural Pools, which designed the first public natural pool in the U.S.­ — Webber Natural Swimming Pool in Minneapolis. The regeneration zone is a carefully constructed ecosystem. The good plants and microorganisms outcompete harmful substances, leaving them no room to grow.

A mechanical pump circulates water between the swimming and regeneration zones. It keeps the water filtered at regular intervals. The Webber Natural Swimming Pool filters its entire volume — 500,000 gallons — every 12 hours. The movement also prevents mosquitos from breeding since they target stagnant water. Traditional skimmers capture leaves and other debris.

What Maintenance is Required?

The cost of upkeep is minimal. “Natural pools require exponentially less maintenance than a traditional pool since they’re largely self-cleaning,” Bailey says. You won’t need to buy or mix chemicals. Some maintenance for a natural pool is the same as a traditional pool, such as sweeping the walls or vacuuming the bottom. Some of it isn’t, like pruning the wetland plants in the regeneration zone. Many people love caring for the water garden.

You can DIY most of the maintenance, but like any pool have it checked regularly by a professional. Europe-based Woodhouse Natural Pools recommends every three to five years.