Guaranteeing drinking water in quantity and quality for all.
The KLS Filter is a prefabricated, simple and durable slow filtration system that operates without electricity and without chemicals. Installed for over 20 years in alpine pastures, mountain huts and isolated villages of Switzerland and Europe, it continuously delivers drinking water compliant with current standards — from 200 litres per day.
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The KLS Filter is a prefabricated slow drinking water filtration system, designed and manufactured in Switzerland since 2002. It treats spring, stream or rainwater through a succession of filter layers — gravel, quartz sand, bauxite — operating by gravity alone, without electricity and without chemicals.
Result: water compliant with Swiss drinking water standards, with turbidity below 1 NTU and complete elimination of pathogenic bacteria — at a flow rate of 200 to 120,000 litres per day depending on the model.
Four pillars that make the difference
Proven technology
3 to 4 successive filtration steps over gravel and slow sand, operating by gravity. A technology inspired by natural soil filtration, mastered for over 20 years.
Guaranteed performance
Turbidity below 1 NTU and complete elimination of pathogenic bacteria. A flow range of 200 to 120,000 litres per day to meet all needs, from isolated huts to villages.
Environmental responsibility
No electricity consumption, no chemicals. Simple, recyclable materials and silent operation that blends into the natural environment.
Economic efficiency
Controlled installation costs, very long lifespan, minimal maintenance achievable without specialised technician, and easily available, low-cost filter media.
20 years in the field. Measurable results.
Of field experience, since the first installation in in the Swiss Jura.
Installations carried out in Switzerland, Europe and Africa, in varied contexts.
A modular range covering all needs, from the shepherd's micro-filter to the concrete basin for villages.
Pathogenic bacteria elimination rate, resulting turbidity below 1 NTU.
Installations that speak for themselves
From the first Jura farm treated in to the most remote alpine huts, each installation demonstrates the long-term reliability of the KLS Filter.
First KLS Filter installation
Treatment of an agricultural spring at 5,000 L/day, combining gravel filtration and two slow sand steps with a final bauxite stage. Still in service.
Treatment of a karst spring
Treatment of karst spring water in a buried polyethylene chamber 3 m in diameter. Capacity: 4,000 L/day. Installation carried out for the Swiss Alpine Club.
Jointly developed and distributed
The KLS Filter is a solution jointly developed and distributed by RWB Groupe SA and Etertub, two specialists in water engineering and prefabricated installations.
