Having as database the book ' ' Superficial emanations in the State of Minas Gerais (1993) ' ' , some information concerning the hidrolgico behavior in the city of Itabirito had been extracted. It was evidenced that the region confers with areas of regularized regimen (intense intra-annual variation with little full and less sharp estiagens). This implies a lesser propensity floodings and droughts. Moreover, it was analyzed, of general form, the specific income – REVERSE SPEED – (l/s.km ) of the city. It was gotten as resulted that this value is changeable in all commune due to the difference of the declivities and litlica composition, conferring an average specific income monthly minimum with 10 years of recurrence, greater in the serrana region, located the west of Itabirito (5,0 city, whose sampling it consists of only one point (BV035), located downstream of the city of Itabirito, as MAP 1, ANNEX. In this study, the ambient pointers of superficial waters is the Index of Quality of Waters – IQA and Contamination for Toxics – CT. As result of 2 campaign of 2009, which consists of the monitoramento of superficial waters, carried through for the IGAM, was evidenced, in the point of monitoramento (BV035) situated in the river Itabirito downstream of the city, a general IQA in the sub-basin of the river general bad Itabirito and CT decrease (IGAM, 2009, adapt.).

The main parameters in disconformity with Joint DN COPAM/CERH 01/08 are: total turbidez, color, solids, coliformes and manganese. The contrary results are related to the activities minerarias of the region, deforestations, erosion, assoreamento, irregular land divisions, to the pollutants of diffuse origin and the launching of sanitary sewer proceeding from the city of Itabirito. It fits to stand out that the river Itabirito tranfers the urban area, in which was verified the presence of very next residences to course d? water in question, not respecting the band of Area of Permanent Preservation – APP.