It may be time before Americans accept natural swimming pools like they have in Europe. For those who can't tolerate chlorine or other pool chemicals, the natural swimming pool (NSP) runs in the front of outdoor home improvement trends on the Continent. In Austria and Germany, NSPs in public parks and spas handle more than 4,000 swimmers a day without any compromises in water quality. In England, they're called swim ponds and rely on native plants to filter and clarify the water.
Writer Michael Littlewwod reports that the trend toward NSPs in Europe began in 1985 when a company called Biotop created a self-cleaning process for pools using water circulation and plants. Plants, the company found, have ecologically balanced, natural skimming and filtration properties. In Europe, swimming pools are worked directly into the landscaping scheme.
A California company, Expanding Horizons, is embracing natural home improvement trends in creating a hybrid pool. The system employs conventional drains, surface skimmers, and sweepers, but circulates the pool water through a separate cleaning pond or restoration area where plants do the heavy filtration. The restoration area is packed with micro-organisms including beneficial bacteria that interact with the plants and water.
Build your own natural pools
Mother Earth News says you won't need steel reinforcement if you dig your pool walls with slanted sides that drop one foot for every three horizontal feet. You end up with a bowl shape pond, rather than one with straight sides. At least half of the surface area of the pool should be reserved for shallow water plants that handle the cleaning.
The most important consideration is how to get the water moving. No movement, no filtration. Using a pump as well as underwater aeration (using a compressor) will handle that responsibility. The pool should be aerated from four to eight hours a day. Be sure to safeguard all wiring that runs to the equipment by burying it in a conduit.
The bottom of the pond should be covered with bentonite clay, according to Mother Earth News, topped with five inches of gravel. The gravel makes a great homestead for beneficial bacteria. Edge the top rim of the pond with rock or wood decking to prevent soil from eroding into the pond.
A swimming pond or natural pool is a great way to transform your landscaping, creating a rural scene of a bubbling brook or Asian garden. Talk about a fabulous home improvement project!