Hydraulic Performance of Zuzu-Nala Water Distribution Network using EPANET in Dodoma, Tanzania

Abstract

This study evaluated the hydraulic performance of the Zuzu-Nala water distribution network in Dodoma, Tanzania, using EPANET 2.2 simulations. Water demand was estimated from population growth projections, per capita consumption, and a 20% Non-Revenue Water allowance, while the hydraulic model was calibrated and validated using field pressure measurements from representative control nodes. Validation statistics indicated strong model performance (R² = 0.95, NSE = 0.95, RMSE = 3.83 m). The results showed pressure imbalance, with very low pressures in high-elevation areas and excessive pressures in lower areas; flow velocities were also low (<0.6 m/s), and head losses were high along the main trunks. The baseline Pressure Reliability Index (PRI) was 78.5%, indicating acceptable but inconsistent service delivery. A combined optimization package involving pipe resizing, network looping, and pressure regulation improved the PRI to above 90%, demonstrating that targeted hydraulic interventions can strengthen system reliability without full network replacement.