A decision support system for aiding watercourses classification processes

Abstract

Economic and social development has imposed challenges for the management of water quality, leading to conflicts among users and the need to develop tools and regulatory frameworks to protect water resources. In this study, a decision support system (DSS) was developed to assist the phases of diagnosis, prognosis, and monitoring, resulting from the implementation and monitoring of water bodies classification processes. The construction of the DSS involved the integration of a mathematical model of water quality and water quality permanence curves within the geographic information system (GIS) environment. By adopting water quality permanence curves, the DSS allows decision-making based on the frequency of compliance with the maximum allowable load of the pollutant under different flow conditions, considering scenarios of pollution increase or control. The DSS was applied to the Jucu river basin as a case study, where it was possible to identify the watercourses most impacted by pollutant inputs and which quality parameters require attention to compliance the quality conditions of the most restrictive classes. By allowing the joint visualization of field monitoring data with water quality permanence curves, the system allows the monitoring of established quality goals and may assist decision-makers in revising goals or improving pollution management. The results indicated that the developed system is useful in assisting managers to define fair water resource management rules and can be applied in the definition or monitoring of water bodies classification in other river basins.