A natural swimming pool brings to mind a lake or pond in the backyard. This visual it not far off. Anyone who wants a watering hole that blends into its surrounds should consider getting a natural swimming pool. Here's what you need to know about this type of pool.
What Is a Natural Pool?
A natural pool is a swimming pool that uses plant life to maintain the water instead of chemicals. They use walls, filters, and plant life to keep the water clean.
Pros and Cons of Natural Pools
When deciding if a natural pool is right for you it is important to understand what you will be getting into. A natural pool does not use chemicals but instead requires a section of the pool that is just for water filtration. This would make a smaller-sized natural pool unfeasible because of the space requirements.
Also, since there is plant life involved, natural pools cost more to install than their more traditional counterparts. Over time however, cost to maintain a natural pool should be less because of the lack of chemicals needed and, if properly designed, absence of maintenance during the pool season.
Natural pools are also more environmentally friendly because of the lack of chemicals. They also provide an environment that can be a nesting area for frogs and other wildlife. Also, natural pools have an added benefit of not irritating skin or eyes because they do not require chemicals to clean the water, thus making it an excellent choice for someone that would like a pool but is sensitive to chemicals.
Does not use chemicals
Lower maintenance cost
Does not irritate skin or eyes
Uses part of pool space for filtration
Higher installation cost
Small pools are unfeasible
If not properly designed the pool will not work correctly
Installing a Natural Pool
Installing a natural pool differs from a standard pool installation in a few key ways. For a standard pool you would dig a hole to put a frame with a liner inside and then backfill to the frame. For a natural pool you would dig a hole in the same manner, but the hole becomes the pool instead of housing a supporting structure that is put inside the hole.
After the hole is dug and the walls have the proper slope (which should be at an approximate 1:3 slope to mitigate mud slides), you lay out the swim zone and the plant zone. This ratio is very important because if it is incorrect your pool will not function correctly. The plant zone creates a mini ecosystem that results in the pool cleaning itself, so it must be done right.
Once you have the areas of the pool marked out, you seal the ground so when the pool is filled the water stays in and doesn't drain out. The most common and easiest way to do this is to lay down a thick plastic liner on top of the dirt. The liner is then covered with 4 to 5 inches of gravel to create a bed for good bacteria to grow — this will also help with the ratio of natural life to swimming space in the pool.
With the hole dug and sealed and the zones laid out, the next step is to add a way for you to get in the pool. Since the slopes on a natural pool can be too steep to walk down but too shallow to jump into, natural pool owners sometimes build a dock that extends out into the pool to allow people to enter the pool past the shallow part and in the main swim zone. You could also install stone steps or build up the side walls slightly to help secure the dirt walls.
After your steps or access route is in and the hole is dug and sealed, you must add your plants. Do research on what kind of plants (and how many you will need of each) will be able to keep your pool clean in your specific environment as this varies depending on your geographic area.
Best Plants for Natural Pools
Chemical-free natural pools rely on perennial plants and water flora to act as natural filters that keep them clean. In addition to the controlled use of algae, there are four main types of aquatic plants used for natural pools (and ponds):
- Emergent plants: Tall grasses, rushes, and reeds, such as papyrus
- Submerged plants: Rooted below the water's surface, such as pondweed and water hyssop
- Floating plants: Floats on the surface of the pool, such as water hyacinth and duckweed
- Marginal plants: Grows around the edges of the pool, such as swamp hibiscus
Aquatic Plants and Algae. Penn State Extension.
5 Types of Aquatic Plants in Natural Swimming Pools. BioNova.