The Alteration

The indiscriminate alteration and use same of its quality due to the polluting discharges, come becoming it each scarcer time (COAST, L.L., et al, 2003). The pollution of the water if of the one for the alteration of its aesthetic, physical or ecological characteristics for any actions or interferences, they natural or provoked by the man are. The resultant effect of the introduction of pollutants in the aquatic way depend on the nature of the introduced pollutant, the way that this pollutant covers in the way and it use that if makes of the water body (BRAGA, 2005). The main aquatic pollutants are the biodegradveis organic pollutants, organic relcacitrantes (refractory), metals, nutrients, pathogenic, solid organisms in suspension, heat and radioactivity.

The treatment of sewer is one of the systems of reuses planned and managed and that it brings ambient improvements and of health conditions. This I reuse makes possible to prevent the discharge of sewer in bodies of water, to preserve underground resources and to allow the conservation of the ground (DAYS, 2009), a time that these contaminantes can infiltrate until freticos sheets and drain for lakes, rivers, lagoons, seas causing its deteriorizao (WHITE, 1986). In developing countries, as Brazil, the public health, the social quality of life and conditions they feel consequences of the projects associates to it I reuse a time that the reused water serves for use in agriculture, has seen to be the sewer treat a fertilizer source natural that guarantees a good productivity of the irrigated cultures. Most of these sewers that are launched in aquatic bodies does not receive treatment. The domestic sewer poured in these hdricos bodies serves of food for decompositoras aerobic bacteria, that increase its in agreement amount the increase of organic substance, and how much bigger the concentration of bigger organic substance the oxygen consumption.