Evaluation of the Water Quality of the Jucu/ES (Brazil) River, Through Physical–Chemical and Biological Parameters in Favor of the Sustainability

The Jucu River is one of the main rivers of the state of Espírito Santo/Brazil. The conditions of the waters of the river were studied by physical–chemical parameters, such as temperature, electrical conductivity, dissolved oxygen, turbidity, total solids, dissolved and suspended solids, biochemical oxygen demand, chemical oxygen demand, total nitrogen, thermotolerant coliforms and Escherichia coli, trace elements, and phytotoxic effect using Lactuca sativa as a bioindicator. The results of the surface waters were compared with the resolution of the Environment National Council (CONAMA) nº 357/05, and the sediments with the resolution of CONAMA nº 420/09. The study revealed that the physicochemical parameters are in agreement with the resolutions. The application of the water quality index (WQI) showed that in the 2nd campaign, the waters were damaged due to rainfall, leaving the river with more contaminants. Besides, it was possible to observe that the stations JUC01, JUC05, and JUC06 are the ones that suffer the most from anthropogenic actions due to the high presence of Escherichia coli, which is related to fecal contamination. All the stations of the Jucu River presented contamination by dissolved iron, aluminum, and manganese in superficial waters, being above the allowed limit. The water samples showed a stimulating effect on phytotoxicity tests.