Avaliação da qualidade das águas do riacho Caquende, Cachoeira, Bahia, para fins de abastecimento humano

Abstract

Water is an essential resource for life on the planet, and its monitoring is of great value to a healthy quality of life. Therefore, the ordinance n ° 2914 / 2011do Ministry of Health defines some physicochemical and biological parameters, which are used to assess water quality and recommended uses. This article is a study of quantitative and analytical investigative character, in which the objective was to evaluate the physico-chemical and biological conditions of Caquende the creek waters (WaterfallBahia), for the purpose of human supply by the local community. The Caquende Creek is located in Caquende District in the city of Cachoeira / Bahia, which flows into the Rio Paraguaçu. At first it was made a community consultation for information on the level of water use, bibliographic study and sequence was made one involving 2 field research (two) campaigns and three (3) different sampling points with three samples per point. The first campaign was held in August 2014 and the second in January 2015. The water was classified and assessed taking based CONAMA Resolution 357/2005, because it is considered class II water. The samples were collected, packaged and sent for analysis and laboratory certified to ISO 17025. They were the parameters evaluated as temperature (on site), hydrogenic potential (pH), Biochemical Oxygen Demand (BOD), Total Dissolved Solids (TDS) turbidity, dissolved oxygen (DO), Total Solids (TS), coliforms thermotolerant (CTT), phosphorus (P) and nitrogen (N). These parameters were used for both calculating the IQA (CETESB), and for separate assessment for each parameter per point. The results showed that the Caquende stream waters are in accordance with Resolution CONAMA 357/2005 there is no information that would prohibit their use. The waters were classified as water quality, and may be used for human supply after treatment.