Modeling and Hydraulic Performance Evaluation of Existing Water Distribution System: The Case of Merawi Town

The study assessed the hydraulic performance of Merawi Town’s existing water distribution system using WaterGEMS V8i, focusing on key parameters like pressure, velocity, water supply coverage, and losses. The system includes 240 nodes, 827 pipes, and two reservoirs. Results showed that only 35.14% of the population was served, with a low per capita consumption of 25.33 liters/day. Annual water loss was 15.08% (61,952 m³), of which 60% was real and 40% apparent. Pressure analysis revealed that during peak demand, 45% of nodes had acceptable pressure (15–70 m), while 53% exceeded the maximum limit (>70 m) and 2% were below the minimum (<15 m). During low demand, 53.8% were within range, while 53% still experienced excess pressure and 0.8% was below minimum. Velocity performance was poor, with only 8.8% of pipes operating within the acceptable 0.6–2 m/s range, and 91.2% below it, indicating flow inefficiencies.

These findings highlight critical issues such as low coverage, significant water loss, high pressure, and low velocity, suggesting the need for corrective actions including installation of pressure-reducing and air release valves and operational improvements to enhance system performance and water delivery efficiency.