Development of a traceability and causal visualization tool in WWTPs

Abstract

Wastewater treatment plants (WWTPs) generate large volumes of operational data typically used for real-time supervision and control. This work presents a historical data-based tool for traceability and causal visualization in WWTPs, applied to a facility in Castilla y León, Spain. The proposed methodology enables the detection of regulatory non-compliance events in the effluent, the characterization of the system state through operational variable analysis, the identification of external disturbances using seasonal percentiles, and the evaluation of corrective actions by statistical tests and dynamic residual analysis. The results are synthesized into Sankey diagrams that represent cause-effect-response relationships, facilitating the interpretation of events and operational decision-making. The tool, implemented in Python, supports diagnostic tasks, operator training, and the continuous improvement of WWTP operations under real conditions.