Determination of some physical and chemical parameters in public water supplies in RibeirÃo preto-SP, Brazil

Water used for human consumption must attend to minimum conditions in order to be ingested or used for domestic, industrial and sanitary purposes, what is achieved by its treatment. Public supply in Ribeirão Preto – SP-Brazil comes from groundwater, an important place for water resources, as it is located in the recharge zone of Guarani aquifer, one of the world’s largest aquifers. This work aimed to determine and monitor the quality of water regarding water turbidity and the presence of nitrates and metals, from water wells of public supply of Ribeirão Preto – SP - Brazil. The levels of cadmium, zinc, copper, iron and chromium were determined by atomic absorption spectrophotometry, presence of nitrate and water turbidity were also determined by the spectrophotometric method. Samples were collected from five water wells located in the wast area of the city. The comparison of the levels of metals, nitrate and water turbidity to the limits established by the national legislation of Ministry of Health decree n. 518, from March 2004, shows that the allowed limits were not exceeded.

 Keywords: Guarani aquifer, water quality, public supply water