Natural pools, or swimming ponds, started in central Europe and have been around since the 1980's. The idea is to create a swimming pool that imitates nature. Just like modern waste treatment facilities are looking at biological filtration to clean up our sewage, the same can be achieved on a smaller scale in a natural pool.
The natural pool consists of a swimming area, which should be at least 2.5m (8 feet) deep, and a regeneration area. This regeneration area can, as is the case in ours, surround the swimming area. It can also be entirely separate, as long as pumps move the water back and forth between the two areas.
How does it work?
The key to natural pools is to keep decaying bio-matter to a minimum within the pool. Whatever bio-matter remains will be food for the naturally occurring bacteria in the gravel within the regeneration area, and whatever the bacteria don't use up, the plant matter planted in the regeneration area will. This keeps your pool crystal clear and algae free.
There are several ways of setting up your regeneration area. If you have a lot of space, and not a ton of people using your pool, you may go for a straight pond with a regeneration area that is roughly the same size as the actual swimming area.
If you have more traffic, or not as much space, you can augment your regeneration area with filtration and pumps. If you add pumps that circulate the water, there are several advantages. One, and probably the biggest, is that you will not have any mosquitos, guaranteed. The second is that by taking water from the swimming area and redistributing it under the gravel you will be able to use the whole depth of the gravel as a filtration area, and you will be able to either make the regeneration area considerably smaller (down to 1/3 of your swimming area), or your pool will be able to handle more traffic and more bio-matter. The third advantage is that one of my pumps is set up so that I can vacuum the bottom of my pond, making it easy to reduce bio-matter in the swimming area.
There are many additional variables involved in the amount of bio-matter that enters your pool, including the quality of your water, the type of gravel, the purity of the rain in your area, the types of plants that grow in your climate, the surrounding trees, flowers and shrubs, and the types of animals in your area. This uncertainty, and the fact that I only wanted to build this pool once, made me choose to put in a pump system into our pool, in order to be able to give me direct control over the amount of filtration required.
Depending on water temperature and the amount of traffic I can vary the amount of filtration in my pond through timers that control the pumps. Our swimming pond is about 50x70 feet and I approximate that it holds about 400,000l of water. According to the literature, it is suggested that about 1/3 of a natural pool's volume is circulated every hour, which would mean about 133,000 l per hour for our pool! I have two pumps in my pool that will handle about 65,000l per hour at peak output, and that, combined with a relatively large regeneration area, fairly clean water, and a bit of diligence in keeping bio-matter out, has been a very successful combination so far. Last summer we saw a fair amount of traffic and the pond was beautiful and clean all summer long.
If you are interested in building a natural swimming pool or pond, feel free to contact me and I can assist you in the planning stages, or if you wish I can quarterback the build for you. Email me to set up a free initial consultation.
- Swim in chlorine free, beautiful water
- Provide habitat for wildlife like frogs, insects, birds and bats
- Enjoy pristine nature in your backyard
- Lower cost to build
- Lower cost to maintain
- More environmentally friendly
- You need more space - anywhere from 1/3 more to twice the amount a regular pool does
- You need to be ok with little critters, like frogs, insects, dragonflies and other lovely aquatic beings sharing your pool with you.
- Our pool averages 23-27 degrees Celsius, so if you need it warmer than that, it may not work for you