Developing a Hydraulic EPANET Model for the Mwengemshindo Water Distribution Network in Songea municipality, Ruvuma, Tanzania

Reliable hydraulic simulation models are important for assessing water distribution networks in rapidly expanding peri-urban settlements where demand growth may exceed existing system capacity. This study developed and validated an EPANET hydraulic simulation model for the Mwengemshindo water distribution network in Songea Municipality, Tanzania, to support hydraulic assessment, operational analysis and future network optimisation. Primary and secondary data were collected using various standard methods, including field measurement of nodal pressures, flow observations, pipe network information and nodal elevations. Spatial data were processed in QGIS, while hydraulic simulation was conducted in EPANET using a network consisting of approximately 758 junction nodes and 316 pipes. Model calibration was carried out through iterative adjustment of Hazen-William’s roughness coefficients, and model performance was evaluated using coefficient of determination, Nash-Sutcliffe Efficiency, Mean Absolute Error and Root Mean Square Error. The calibrated model showed strong agreement between observed and simulated pressures, with mean R² of 0.996, mean NSE of 0.995, mean MAE of 6.95 m and mean RMSE of 8.41 m. Validation also demonstrated high predictive performance, with mean R² of 0.999, mean NSE of 0.998, mean MAE of 4.70 m and mean RMSE of 5.85 m. The findings confirm that the developed EPANET model reliably represents the hydraulic behaviour of the Mwengemshindo network. The study recommends using the model for pressure monitoring, demand management, pipe improvement planning and future hydraulic optimisation. Its contribution to knowledge lies in demonstrating how integrated QGIS–EPANET modelling can support evidence-based management of peri-urban water distribution systems in Tanzania.