as the main source of water supply the underground aquifers. The present work concerns the determination of physical, chemical and bacteriological parameters of the urban water supply of the region. The water samples were collected in April/2004 (rainy period) and seU2004 (dry period), in 20 points distributed between public supply system (PS) and individual supply system (IS). In the field, temperature, electrical conductivity, pH and salinity were measured. In the laboratory, the following were analyzed: total alkalinity, chloride, sulfate, phosphate, silica, ammoniacal nitrogen, total iron, K+, Na', Ca+2, Mg+2, dissolved oxygen, 000, total and fecal coliforms, according to Standard Methods (1998). The results were framed in the Ordinance 518 of the Ministry of Health (2004). The temperature reflected the climatic conditions of the region. The pH values, in both systems, characterized the waters as acidic. The electrical conductivity showed waters rich in dissolved substances. ° chloride was the most abundant anion, which probably evidences the intrusion of seawater into the aquifers. The predominance of the ions is: Na+ > Ca+2> S04- > K+> Mg+2> P04 - (rainy period) and CI- > Ca+2> Na+ > S04- > Mg+2> K+ > P04 - (dry period). ° Sodium, sulfate and chloride are in conformity with the standards. ° iron content at SP-6, SP-7, SP-8, SI-9 and SI17 exceeded the permitted limit of 0.3 mg/l. As well as the ammoniacal nitrogen in points SP-3, SI-9 and SI-11, whose levels were higher than the maximum limit of 1.5 mg/l. Fecal coliform indices were detected at points SI-9, SI-11 and SI-16 in both seasonal periods. The values of 000 at points SP-8, SI-9, SI-11 and SI-17 (dry season) and SI-16 (rainy season) exceeded 15 mg/L of 02' The waters can be classified as chlorinated calco-magnesian type. The results of the analyses were presented to the Secretary of Health of the municipality and to the owners of the wells analyzed through a technical report and an explanatory booklet. The aquifers in the region suffer interference from both natural and anthropogenic sources, reflected in the characteristics of the water, which can cause health risks to the population.
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