Conditioning of drinking water on constructed wetland: Elimination of Escherichia coli

A constructed wetland is, in brief, a water treatment facility. Duplicating the processes occurring in natural wetlands, constructed wetlands are more complex, integrated systems in which water, plants, animals, microorganisms and the environment interact to improve water quality. In local water reservoirs, especially in the countryside, excessive pollution occurs frequently, in particular microbiologic pollution, which is most often a result of poorly safeguarded water protection areas. Agricultural activities can be the cause of increased content of nitrates, pesticide residue and microbiologic pollution. The existing technological solutions (e.g. membrane and absorption filters) are too expensive and difficult to manage in case of small water supply systems. Commonly used chlorination or ozonization does not remove harmful nitrates. Also, nitrates cannot be removed by adsorption agents (activated carbon, quartz sinter, diatomaceous earth, etc.), but they can be removed by reverse osmosis or chemically (ionic exchangers, etc.). Constructed wetlands (CW) are expected to provide a certain solution to all above-mentioned problems. If a suitable mechanical system of particles removal (inorganic and organic particles) is used, there is no need for additional filtering.