Diagnóstico da qualidade da água superficial e subterrânea na microbacia do riacho Angico, região do médio rio Paraíba.

Abstract

The present research accomplished a diagnosis of the surface and underground waters of the Angico's River watershed, which is a tributary of Sao Pedro River, aiming to evaluate its use for human consumption, irrigation and animal consumption. During a period of 11 months of research water samples were collected from 17 sources, corresponding to 5 tubular wells with weather vane, 8 amazon wells, among which 6 are inserted into the underground dams, 2 dams and 2 natural water-holes in the bed of the stream, totaling 98 samples for chemical analysis and 76 for microbiological analysis. The results showed that the waters for human consumption had, in a chemical point of view, the amazon wells into the underground dams as the most appropriate sources. The dams presented restrictions due to high values of iron. The other sources presented values superior to the ones recommended by the World Organization of Health and by the Brazilian Ministry of Health. Regarding the microbiological or sanitary quality, the water was not shown appropriate for the human consumption in none of the studied sources, needing treatment following by disinfection. For irrigation, water of excellent quality doesn't exist in the watershed, because when a source exhibited low salinity risk, it presented simultaneously, high sodification risk, happening the opposite in other sources. For the animal consumption, the amazon wells into the underground dams and the dams presented without restriction. The tubular and amazon wells can also be used for animal consumption, but with potential to provoke temporary diarrhea in cattle no accustomed with that type of water. However, it was verified that the water of the Sao Pedro River that receives water from the Angico's River, comes to have temporarily (September to December) high concentrations of salts, so becoming inappropriate. Finally, it is concluded that it is indispensable a systematic monitoring of the quality of water for multiple uses.