Avaliação da qualidade da água do Córrego Trindade, no município de Itumbiara-GO.

Abstract

The use of water resources has always been essential for humanity, both for economic and social development. In Brazil, the agency responsible for monitoring the quality of surface and underground water is the National Water Agency - NWA. One of the parameters established by ANA was the Water Quality Index - WQI, a qualitative indicator that assesses water for public supply. The main objective of this work was to analyze the nine physical-chemical and biological parameters of the water quality index of the Trindade stream located in the municipality of Itumbiara-GO. The collections were carried out on the 7th of November 2021 in the city of Itumbiara-GO, after approximately 10 days without rain in the region. The quality parameters analyzed are Dissolved Oxygen - DO, Thermotolerant Coliforms, Hydrogen Potential - pH, Biochemical Oxygen Demand - BOD, Water Temperature, Total Nitrogen, Total Phosphorus, Turbidity and Total Residue. 3 points were chosen: the first point chosen was when the stream enters the city, the second point in the middle of the city, the third point at the end of the stream. By the calculations of the WQI, the Temperature, pH, BOD, Phosphorus, Total Nitrogen, DO, Total Residue and Turbidity parameters were within the allowed for classification of a body of water as good, only the Thermotolerant Coliforms parameter was outside the allowed, classifying the value of the WQI for good and reasonable water. The Trindade stream receives urban solid waste discarded by the population and is constantly contaminated by undue dumping of effluents characteristic of domestic sewage coming from a fluvial gallery. It is concluded that even the stream receiving all kinds of pollution and contamination from the surrounding environment, eight parameters were within the allowed for Class II fresh water.