Desenvolvimento de sistema de suporte à decisão como subsídio ao processo de enquadramento de cursos d’água

Abstract

It was developed a decision support system to help the stages of diagnosis, prognosis, and monitoring, during water courses reaches water quality classes definition. System and interface construction considered available programs (IPH-Hydro Tools and WARM-GIS Tools), making the focus of this work programming of methodological steps routines for which there are no available programs (CPQ-WATER). The IPHHydro Tools was used to appropriate the vector files (shapefiles) of mini catchments limits, segmented drainage network and basin topological data. WARM-GIS Tools was used to simulate water quality and assess self-purification capacity, according to different effluent treatment and population growth scenarios, and considering selfpurification. The CPQ-WATER allowed construction of quality permanence curves and estimation of total dilution capacity, load to be treated, unused dilution capacity, pressure level and self-purification capacity. Additionally, it supported the water quality classification monitoring stage, superimposing the quality permanence curves and the watercourses quality conditions field monitoring results. Critical analysis of SSD limitations was performed. The SSD was applied to the Jucu River basin as a case study. The SSD, by incorporating GIS tools, provided the spatialization of the information allowing results graphical and cartographic visualization for any basin river stretch, parameter and water quality class. By applying the SSD to Jucu River basin, it was possible to verify industrial effluents contributions influence as well as to identify that Vila Velha and Viana municipalities are the largest pollutant producers located in the basin. When simulating self-purification capacities, it was possible to observe that the basin rivers present high pollutant load assimilation capacities, although for some stretches the assimilation capacities are insufficient to improve water quality, as desired, indicating that sewage treatment systems would need improvements. The application of quality permanence curves for the Jucu river basin indicated that the parameters coliforms, total phosphorus, and BOD, in this order, are limiting the classification of water quality in stretches near sewage discharge points. Results analysis indicated that the Jucu Braço Sul River tributary represents the most impacted watercourse in the basin, by presenting the lowest frequencies of compliance with the standards for the most restrictive classes. The highest loads to be treated were observed from the perspective of meeting classes 1 and 2 quality conditions, indicating the need for improvement in the domestic and industrial sewage treatment systems. When relating water quality monitoring data with quality permanence curves, the SSD indicated that the Jucu River, in the section chosen for analysis, presented aligned with class 1 of water quality, being this class the legally defined for the stretch. As limitations, inconsistencies were observed in relation to the use of the WARM-GIS Tools model and non-applicability of SSD in drainage sections under the influence of the tide.