Ismailia Sewage Treatment Plant operational monitoring dataset, 2000–2008.

The corresponding author uploaded the raw operational monitoring dataset used in the manuscript entitled “Interpretable Machine Learning and Rolling-Origin Validation Identify Two Distinct Control and Predictability Regimes in Full-Scale Aerated Lagoon Performance.” The dataset contains daily monitoring records from the Ismailia Sewage Treatment Plant (ISTP), a full-scale aerated-lagoon wastewater treatment plant located in Serabioum, Ismailia Governorate, Egypt. The record covers the period from 2000 to 2008 and includes 8,211 complete observations representing 2,737 sampling dates across three in-series lagoon stages: aerated, facultative, and maturation lagoons. The dataset includes influent, operational, and stage-specific effluent variables, including BOD₅, TSS, fecal coliform, temperature, flow, pH, VSS, and DO. The files are provided in CSV and Excel formats, with the Excel file including a data dictionary to support reuse and interpretation.