What is a natural swimming pool and how does a natural swimming pool work?
A natural swimming pool is free from chemicals like chlorine.
These natural swimming pools which have been popular in Germany and Austria are now gaining popularity in the UK.
Learn more about how natural swimming pools work here!
What is a natural swimming pool?
A natural swimming pool is a swimming pool that requires no chemicals.
With the use of water flora and perennial plants, these swimming pools are cleaned naturally.
The goal of the natural swimming pool is to prevent the formation of algae, thus reducing the nutrients in the water which helps to keep the water clear.
How does a natural swimming pool work?
A natural swimming pool without chlorine can provide water quality either above or equal to the community standards for bathing water.
Natural swimming pools depend on moving water or filters for heavy lifting.
In order to keep the silt and soil out, the natural swimming pools are built with membranes or walls.
These pools can be converted from an in-ground pool that is existing or can be constructed from scratch.
To absorb phosphates and to encourage the growth of good bacteria, the natural swimming pools use biological filters like natural shale.
Good bacteria are promoted to reduce or discourage the growth of bad bacteria and algae.
Adjacent to the swimming area, a ‘regeneration zone’ is constructed which is filled with plant life.
These plants act as a natural filter and they can also be used along with a special pump for water filtration.
The water always flows around the plant life thereby preventing unwanted organic material from growing in the area.
In places where the climate is warmer, materials that act as natural filters are installed in the pool. Hydroponic plants also help in the filtration system.
Shapes of a natural swimming pool:
A natural swimming pool can be rectangular in shape or informal constructed on a leveled site.
They can be irregular in shape and are found along with waterfalls, boulders, and rocks.
A shallow stone bed is used to separate the filter bed and the natural swimming pool.
This band of stone should be between 100 and 200 mm in width.
Why should you consider a natural swimming pool? (Pros and Cons)
Now that we know how the natural swimming pool works, let’s look at some of the pros and cons of using a natural swimming pool!
The number one reason you should consider a natural swimming pool over the chlorinated ones is that they are chemical-free.
They create a natural habitat for wildlife and flora. It aids and supports plants, aquatic life, insects, amphibians, etc.
Some microorganisms can also be found in these natural swimming pools that help to keep the water clean by consuming bad bacteria. Plants like water lilies help the microorganisms by providing shade from the UV rays.
The roots of the plants can act as natural filters for excess contaminants and nutrients in the natural swimming pool.
The water quality is very high.
Plus, as there is no chemical filtration involved in these natural swimming pools, the costs are less and so are the requirements, though the initial investment for a natural swimming pool may be high.
These swimming pools can provide a luxurious style to the property.
Natural swimming pools can be custom-made as per your preferences and it is quite possible to build the entire pool by yourself.
They are not restricted to a particular climatic condition.
They require very little maintenance and are eco-friendly.
The design is more adaptable and flexible when compared to traditional swimming pools.
A large area of land is required for the construction of a natural swimming pool.
Though the maintenance cost is comparatively lesser, the initial cost to build a natural swimming pool may be high.
May not appear bluish as a traditional swimming pool.
The water may appear brownish as it is organic in nature.
How to build a natural swimming pool?
Can you construct a Do-It-Yourself natural swimming pool?
Well, the answer is yes!
Make sure you follow the steps outlined below!
The following steps are to be followed to build a natural swimming pool.
- Step-1: Dig the area on the ground
- Step-2: Zone the pool
- Step-3: Filtration
- Step-4: Sealing the natural swimming pool
Step-1: Dig the area on the ground:
Based on the depth of the pool needed, dig the area on the ground as a first step.
The pool can be shallow or deep but the sides must slope to prevent the soil from caving in.
The ratio must be as follows: For every 3 horizontal feet, there must be a 1-foot vertical drop.
There is no need for any steel reinforcement in natural swimming pools.
Step-2: Zone the pool:
A minimum of 50 percent of the pool’s surface area have to be allocated for the shallow plants that can be cultivated either around the sides or at one end of the pool.
The plant zone and the swimming area must be separated using a rim that could be around 1 inch of the water’s surface.
The water from the swimming area moves to the plant zone for filtration.
The bacteria that are present in the fibrous root of the plants serve as the biological filter and remove pollutants and contaminants from the water.
The plant’s roots also contain decomposer organisms that can eliminate the underwater waste buildup by consuming bacteria.
The water must go steadily deeper inside the plant zone reaching a maximum depth of about 18 inches close to the swimming zone.
The deeper area is occupied by the submerged vegetation.
The shallow plant zone acts as home to many invertebrates that eat up the mosquito larvae while also using the zone as a breeding ground.
To clean the pool using plants’ roots, water circulation has to be done continuously.
The water has to be aerated as well without which the pool could harbor anaerobic bacteria.
To channel the water to the plant zone, PVC tubes buried in the soil are recommended.
At the bottom of the pool, diffused air is required which is provided by the underwater aeration.
Circulation of water is done effectively and the energy required is less in this type.
Using high-strength tubing and an air compressor, an aerator can be built.
Skimmers can be used to remove the floating detritus.
Step 4: Sealing the natural swimming pool
There are two ways to seal the natural swimming pool.
Bentonite clay: The first option is to apply bentonite clay for sealing the soil. This clay bonds with the particles in the soil thereby avoiding the water from the pool to leak into the ground. This clay acts as glue. In some cases, the soil has adequate clay and in these cases, just compacting the bottom of the pond will help in holding the water. Talking to local pool builders would help.
Bentonite could be directly applied to the soil in humid climates. But it is important to note that bentonite does not bond with dry surrounding soil or sandy soil. Before using bentonite on the pool, it is important to compact the soil using a plate or a lawn roller. 2 to 3-inch layer of bentonite should be applied along the bottom and sides of the pool while wearing a mask. After that, another layer of topsoil and compact must be applied.
Liner: In the case of a liner, instead of a PVC, EPDM(Ethylene Propylene Diene Monomer) which is a synthetic rubber is preferred. It is expensive when compared to PVC but it stands flexible during cold weather and offers protection from UV rays. In the case of sandy soils, a 30mm liner can be used. Whereas, when the soil contains lots of roots and rocks, a 45 to 60mm liner would be required.
After applying a layer of either bentonite clay or liner, gravel of depth 4 to 5 inches should be applied at the bottom of the pool. This gravel that is to be used must be clean. At the edges of the pool, along the perimeter, a plate compactor could be run to assist with the soil erosion. Wood planks, rocks, and flagstones can be used along the edges, or planting along the edges would also help in stabilization.
When a conventional pool shape is preferred, materials like cement or Rastra block could be considered. Rastra block is a material that has been manufactured from recycled foam plastic and cement. These are not as eco-friendly as stone and gravel but they help in reducing the chemicals in a significant amount as they use filtration systems that are plant-based.
Because of the complexities involved in concrete pouring, it is not advisable to construct a concrete pool by yourself especially when you are not experienced in concrete work. When a Rastra block is used, a hole larger than the dimensions of the swimming pool is dug. The bottom of the pool is either covered using a rubber liner or a concrete slab is poured. After that, the bottom layer is covered with gravel. A backflow preventer and a drain should also be installed. At the edges, one section of the Rastra block is laid. Using rebar, the Rastra is secured to the pad. The cavities of the Rastra block are filled with concrete. In between the courses, a foam sealant that is expanding is to be used. This is also used at all joints that can help to hold the blocks. In between the Rastra block and the pool sides, the space is backfilled with soil. The perimeter along the edges of the pool can be laid using stones or plants can be grown at the edges of the blocks.
What plants to plant in a natural swimming pool?
Great, we have come this far.
Now, let’s look at what plants to plant in and around a natural swimming pool!
After constructing the pool, allow it to rest for one week before plants are installed.
The plant zone must be prepared using 3 to 6 inches of soil. This soil must be free of contaminants such as organic matter or animal excrement. A lab test for soil samples can also be conducted.
It is important to choose plants that are suited to the climatic conditions of your area.
The best option would be to buy them from a native supplier of plants.
For emergent vegetation, along your pool’s perimeter, sedges and rushes which are both aquatic plants might be a great option.
It is also important to choose plants in such a way that one does not overcrowd the other.
Aquatic irises and lesser cattails could also be considered.
In areas of the pool where water is shallow, consider Pickerelweed, water primroses, and arrowhead.
Owing to their high output of oxygen, submergent plants such as the hornwort and common waterweed could also be some of the best options.
In areas where water is 6 to 18 inches deep, consider a mix of submergent, emergent, and floating plants.
Consider water lilies that can be suitable for any depth.
For floating plants, consider common duckweed and pondweeds.
It is important to be mindful of the laws protecting wetlands, before proceeding to collect plants from the wild.
Natural swimming pool builders, cost and examples
If you want to know the top natural swimming pool builders in your country, costs associated with it, keep reading!
Here are the top 10 swimming pool builders across Europe, according to https://www.exceliteplas.com/.
And a few examples of some incredibly built natural swimming pools. Take a look!
Natural swimming pool builders
Some of the best natural swimming pool builders in Europe are as follows.
- Alba Pools: Alba Pools is a Scotland-based swimming pool construction company that specializes in pools and spas. They also supply swimming pool accessories and equipments. Check them out here – http://ww1.alba-pools.co.uk/.
- Falcon Pool: One of the top 50 companies in swimming pool construction in Europe. They are experts in building standard and customized swimming pools. Check them out here – https://www.falconpools.co.uk/indoor-swimming-pools-surrey/.
- Albixon: Albixon is reputed for its Albistone pools that can be rectangle, oval, round, sharp-cornered rectangle, or atypical pool designs. They also offer swimming pool accessories. Check them out here – https://www.albixon.com/.
- Tanby Pools: Tanby Pools provides customized swimming pool design solutions be it a simple swimming pool or high-end or luxury, based on the customer needs. Check them out here – https://www.tanbypools.co.uk/gallery/award-winning-outdoor-pools/.
- RivieraPool Fertigschwimmbad GmbH: RivieraPool Fertigschwimmbad GmbH, based in Germany, produces equipments known for their durability. The main swimming pool designs are MLine, Style-series, classic, and D-Line. Check them out here – https://www.rivierapool.com/swimmingpools.
- Jetform Swimming Pools: Jetform Swimming Pools offer pool construction, spa sauna, service maintenance, and pool refurbishment. They provide affordable and quality accessories and pools. Check them out here – http://www.jetformpools.co.uk/portfolio/.
- Piscine-Plus: Piscine-Plus offers pool renovation services, above-ground swimming pools, spas, and security accessories. They are known for their Christal Pools which are uniquely shaped. Check them out here – https://www.piscine-plus.com/home/pool-gallery.
- Pebble Pools: Pebble Pools – a pioneer of “the pebble pool” concept in Portugal and Europe specializing in freeform pools, traditional pools, razor-edge & combination pools, and natural rock pools. Check them out here – http://www.pebblepools.com/gallery/image-gallery.
- Roman Pools: Roman Pools has over 25 years of experience in the swimming pool market. They are known for their quality workmanship. Check them out here – https://www.romanpools.com/gallery/.
- Compass Ceramic Pools UK: Compass Ceramic Pools UK – pioneers of composite ceramic swimming pools. They have constructed more than 30,000 pools on a global level. From indoor to outdoor pools, they have got it all covered. Check them out here – https://www.compass-pools.co.uk/our-pools/.
Cost of building a natural swimming pool
The construction of the natural swimming pool, the size, and type required, including the features and many other factors play a major role in deciding the cost of the natural swimming pool.
A natural pool of size 40 m2 incorporating a swim zone of 20 m2 starts somewhere at £40,000.00 plus Vat.
A natural pool of size 100 m2 incorporating a swim zone of 50 m2 starts somewhere at £65,000.00 plus Vat.
A bespoke natural pool of size 200 m2 incorporating a swim zone of 80 m2 starts somewhere at £100,000.00 plus Vat.
Examples of natural swimming pool
- This natural swimming pool is 30FT x 40FT and 20,000 gallons approximately. It contains an underwater wooden wall, a central swimming area, a rainwater collection system, and a step-in pebble beach. This natural swimming pool was built with concrete.
2. This 300 m2 Radwinter natural pool consists of a filter bed stream that runs right from below a glass bridge and false brick to jetties and stepped shallow areas through to a wide round pond.
3. This natural beauty, part of the garden with clean water free of chemicals like chlorine is absolute bliss.
4. Take a look at this amazing natural swimming pool!
5. 90FT x 70FT, more than 200,000 gallons contains granite boulders, pier and stream with bridge, a zero-entry pebble beach, and waterfall.
6. This 60 m2 pool is known for its small geometric designs in an informal setting.
7. “It is so much more than a pool area could be – a place for wildlife and beautiful insects, like Emperor dragonflies; a place to work and just think about things.” – https://gartenart.co.uk/portfolio/092bat/?c=1
8. This natural swimming pool is a 12-foot deep, spring-fed natural swimming pool. It contains a waterfall with a hidden grotto, an 18-foot custom waterslide, and a gentle-entry pebble beach.
9. This 350 m2 natural swimming pool was built by half raising the ground and half digging. This pool has been designed to cope up with a temperature of -30 degrees celsius in winter. It is also very much used in temperatures of +30 degrees celsius when a meter of ice has melted.
10. This natural swimming pool is about 35FT x 60FT and 98,000 gallons approximately. It consists of hot springs, a waterslide, a step-in pebble beach, and an artificial jumping rock.
Planning permission and FAQs
Want to know if you need planning permission to construct your natural swimming pool? Read on!
Also, find answers to some of the most frequently asked questions regarding natural swimming pools.
Conventional swimming pools and natural swimming pools and ponds are included in the same category.
The most up to date regulation from the Town and Country Planning Act 2015, Part 1, Class E stipulates that a client will generally not need planning permission if you meet these key requirements (there are others, but these are the main ones):
- The property is not listed, and
- The site is within the curtilage of the property, and
- You are not in an Area of Outstanding Natural Beauty (AONB)
Planning permission will be required if:
- Your property is listed
- You want to build on agricultural land
1. How to control algae growth in your natural swimming pool?
The best remedy to control the growth of algae in your natural swimming pool is to include more plants. It is also important to monitor the amount of phosphorous in the pool. Increasing the aeration schedule also helps.
2. How to maintain your natural swimming pool?
Removing the plant litter from the pool will help in maintaining the life and durability of your natural swimming pool. Water should be maintained at a constant level. It is important to monitor the pool’s mechanical and biological health. Diffusers must be wiped with vinegar for removal of deposits, air hoses should be checked for obstructions and cracks. All pump connections must be examined.
3. Can you heat the water in a natural swimming pool?
Yes, the water in the natural swimming pool can be heated. However, it is recommended to wait for a year before proceeding.
4. What happens in winter?
Dead plants should be cut away in autumn. There is no need to cover the natural swimming pool during winter.