WATER QUALITY EVALUATION OF A HIDROGRAFIC MICRO BASIN IN THE ILHA SOLTEIRA CITY (SP)

Abstract

This paper has the object monitoring and analyzing the water quality of the Córrego do Ipê Micro Basin, in Ilha Solteira City, São Paulo State, and its degradation stage in association to the utilization of the surrounding area. Thus, once every fifteen days, in the period between March and December of 2002, water samples were collected at three points of this micro basin and some of its physical, chemical and biological parameters were analyzed that allowed to calculate the WQI - Water Quality Indices. In addition, a monthly analysis of the flow was made. The WQI results, jointly to observations in loco, also made possible to evaluate the water quality and check the actual degradation stage of this micro basin that could be noticed by the non-existent ciliary vegetation. It was shown that the pollution in Córrego do Ipê was kept in high level in terms of time and space so its numbers are lower than a Class II level river, especially at Point “B”, located at the urban environment, where the water quality alternates between bad and very bad, which require to take steps for urgent corrections and mitigation at the places that have been more affected and also a sustainable management, which would make possible the conservation of the entire micro basin in analysis.