The purpose of sanitation is to transform water polluted by human activity (domestic, agricultural, industrial) into water that can be assimilated by the natural environment. There are many sanitation solutions on a collective scale such as individual solutions so-called autonomous. All rely on bacteriological activity to clean up contaminated water. Likewise, each system, at the outlet, returns the water to the natural environment by infiltration or leach field. At the sanitation outlet, the water is not drinkable.