How much does it cost to build a natural pool?

First developed in Europe and now making their way to the United States, natural swimming pools offer a greener alternative to the traditional backyard swimming pool. Natural pools use plants to filter the water rather than chemicals, so you spend less time and money on maintenance over the lifetime of the pool.

Natural pools vary in terms of size, shape, depth, and style, which means they differ in cost as well. Typically, prices range from $50 to $100 per square foot installed for a natural swimming pool, with most homeowners spending around $70,000 for a pool measuring approximately 30 x 20 feet.

How natural pools work

Natural pools do not rely on chemicals or machines to clean the water. Instead, they use a variety of plants and a pump ¹ that circulates water through these plants, naturally filtering and cleaning the water.

Every natural pool consists of roughly two, equally sized parts - a swimming section and a regeneration zone. The swimming section is self-explanatory, meaning this is the area you spend your time in. It will likely have stairs, a deck, perhaps a concrete liner, or it may have plants growing right up to a tamped dirt edge.

The regeneration zone is roughly the size of the swimming section and adjoins it. This part is also filled with water, but it is disguised and differs from the swimming section because it is shallower, filled with crushed gravel and a variety of aquatic plants. Underground pumps ¹ and tubing circulate the water between the swimming section and regeneration zone. The water continuously passes through the plants and gravel, which cleans the water naturally. If desired, you may also install a skimmer to help remove algae or small surface particles from the pool, but the majority of the pool cleans itself naturally.

Because the water is continuously moving, mosquitoes do not breed there because they prefer stagnant or stationary water. Small aquatic insects and animals may live in the regeneration zone, which can sometimes resemble a small marsh. The pool stays just as clean as a chemically treated pool, but once it is set up and running, it needs no continuous maintenance. It never needs to be drained, and the plants should keep the pH at a level of around 5.5 naturally. You may also choose to add fish to your natural pool in either section, but it may require slightly more maintenance due to the fish excrement.

Surface area and size

A natural pool is much larger than other types of backyard swimming pools with the same swimming area. This pool must take into account the regeneration zone, which is the same size as the swimming area itself.

Altogether, the pool should be between 45 and 50 square meters, around 500 square feet, in size. Smaller pools do not allow as much circulation and plant growth, which means that the water will not be filtered as efficiently. This could mean that you will need a pool size much larger than you originally intended and with a swimming section that is smaller than average.

Depth

Natural pools are shaped differently than other pools. If you choose a pool liner other than concrete, the sides will slope inward to prevent them from collapsing. The regeneration zone starts at around 6 inches at its edges and gradually deepens to about 18 inches at its center.

The swimming portion of your pool can be as shallow or deep as you desire, if you intend to line it with concrete. Leaving the sides naturally limits you in some areas, depending on your soil.

Natural pools can have heaters like standard pools. If you choose not to use a heater, keep in mind that the depth of your pool affects its temperature. Deeper pools stay naturally colder than more shallow ones, which may be more refreshing. Shallower pools may be better for doing laps.

It is common for natural pools to have depths varying from 3 to 12 feet for the swimming area, but this is based entirely on preference.

Materials

Choose from a few material options to build your pool. For the swimming side, concrete is the most common material and provides the most options for customizing your pool, having a variety of depths, and allowing for straighter walls. Use concrete to create a pool lip if desired or a pool deck and stairs. Many people who use concrete choose to paint it black to help give the final pool a more natural appearance. Concrete costs around $55 to $70 per square foot, depending on the type of concrete pool you choose.

The other option, if you want a more natural-looking and good-feeling pool, is to use bentonite clay to cover the soil. The soil is first tamped down, and then, the clay applied to it. The clay seals the soil so that your water will not be absorbed into the ground. This is a much cheaper option, but it limits the finished pool’s shape, size, and appearance. Bentonite costs less than $1 per square foot, so it is considerably cheaper than concrete.

For the regeneration area of your pool, the bottom must be filled with 5 to 6 inches of crushed gravel, which costs $1 to $2 per square foot. Below this gravel, you have pipes or tubing for the water system. The pool itself can have an infinity edge if using concrete to help it circulate the water. Otherwise, you need discreet areas for the pump and tubing to circulate.

The regeneration area should be filled with a variety of plants as well as crushed gravel. Floating plants and a variety of oxygenating plants are usually combined. Use native plants for best results. Some people also choose to use potted plants for filters. The water filters up through the pots, which can be semi-submerged in the water.

Construction process

The first few stages of building a natural pool area is much like building a standard pool. The area is marked off and excavated to the proper depth. The earth is tamped down around the perimeter, sides, and bottom of the pool. Next, either the pool is lined with clay or the concrete is set up and poured. Then, the concrete is cured and usually painted.

On the regeneration side, gravel is laid down, and the pipes and pump system are installed. Water is slowly added to the pool, and the aquatic plants are set in place. It takes a few weeks for the plants to establish themselves and start filtering the pool. During this time, the pool may appear discolored or cloudy in appearance.

The perimeter of the pool is finished in one of several ways. Plants can be landscaped right up to the edge. And, in some cases, they are also done so on the regeneration side. Sometimes, a partial barrier is constructed to separate the swimming side from the regeneration side to keep floating plants out of the swimming area.

You may install a pool deck, lights, boulders, waterfalls, or other items around the swimming side to create the look you want for the pool. The entire process can take up to 3 months to complete, depending on the size, depth, material as well as the type and number of plants used.

Labor

Labor makes up a large percentage of the pool building costs. Materials cost around $30,000 of the $70,000 total, while the remaining is made up of excavating, machinery, and labor costs. Typically, labor costs around $20 per hour for the process, with total labor and equipment costs making up about $40,000.

Maintenance

Natural pools are incredibly low-maintenance once they are set up and operational. They do not require opening and closing at the beginning and ending of a season and can be left to freeze and thaw naturally. They require the pumps to run for a few weeks at the start of a season to get the filters operating properly before using the pool. You may occasionally need to skim or vacuum the pool to remove sediment or debris. The pump may sometimes need to be serviced to keep it running properly. Otherwise, a natural pool requires no regular or yearly maintenance. This makes it much less expensive to maintain than a standard pool.

Natural vs regular pool

Natural and traditional pools have some things in common. Both can be used for recreational or athletic swimming and made in various shapes, sizes, and depths. However, a natural pool has an equally sized regeneration zone as the swimming area, so it will take up more space than a regular pool. It must also be roughly 45 to 50 square meters (148 to 164 feet), while traditional pools can be smaller.

Natural pools require little to no maintenance, while traditional pools require daily and weekly chemical checks, opening and closing, and yearly chemical costs. Natural pools often look more like a backyard pond or natural habitat, while a traditional pool is often a cool blue color, having a manmade-look.

Natural pools are more expensive, costing around $70,000 on average, while a traditional pool may cost as little as $37,000 for a vinyl pool and up to $60,000 for concrete.

Enhancement and improvement costs

Waterfalls

To circulate the water with a natural appearance, consider installing a waterfall in the pool. They cost around $1,020 on average and can take on many appearances.

Landscape lighting

To make the most of your pool, include lighting in your landscaping. Landscape lighting can disguise the lights so that they blend in with their surroundings, providing the necessary illumination. Lighting costs start at around $2,000 and go up from there.

Sand

It is common to include a sandy section or perimeter around your natural pool to give it the feel of a lake-side beach. Sand has a wide range of costs, depending on its quality. Keep in mind that the lighter the sand, the easier it is to wash into your pool. Sand starts at less than $1 per square foot.

Retaining wall

Some natural pools may be enclosed by a natural-looking border wall. This is usually made of concrete but will have natural stone veneer ² added to it. This enhances the appearance of your pool and sets it apart from the surroundings. The cost of adding this wall starts at around $5,000.

Additional considerations and costs

• Like any swimming pool addition, you need a permit to install a natural swimming pool in your yard.
• Natural pools and regeneration zones create a small ecosystem in your yard that may change naturally over time. Small animals and insects may be attracted to the zone but not to your pool.
• The regeneration zone means that you need more land to build a natural swimming pool than a standard pool.
• Natural pools are considered a green option because they do not use chemicals and can enhance the natural ecosystem of your yard.
• Natural pools freeze naturally in the winter, then thaw and regenerate in the spring.
• Because natural pools are still relatively rare in the U.S., it can be difficult to find a contractor familiar enough with the concept to build one.
• It is common for natural swimming pools to develop a brownish tint due to algae and sediment. This is normal and will not impact the pool’s use.
• Because the water in the pool is constantly moving, it will not become a mosquito breeding ground like other non-chlorinated water areas.
• You can include fish in your natural pool, but it will lead to fish excrement, which will require additional maintenance and cleaning.
• Because you are creating a mini-ecosystem, it is not recommended that you DIY this job.
• Your natural pool requires some form of floating plants as part of the filtration system. You may wish to upgrade to one with an enhancing appearance, such as water lilies.

Remodeling Terms Cheat Sheet

¹ Pump: A device used to move air, liquid, or gas by mechanical means