The Hydraulic Performance Analysis of Existing and Revised Water Supply Distribution Network, a case of Dukem Town in Ethiopia

Abstract

Analysing the status of a town’s water distribution network is necessary to monitor its current and future management patterns. Dukem Town's existing water distribution system is not properly functioning, and the utility does not deliver the required demand to customers due to fluctuations in pressure and demand. Thus, the main goal was to analyse the town's water distribution system’s hydraulic performance and the users’ perceptions. Level of consumer’s satisfaction with the town's water delivery services was examined among 376 households. The WaterGEMS model was calibrated using eight node data points at minimum and peak hour consumption, with corresponding R² of 0.97 and 0.99, respectively. The result of the analysis at steady state simulation indicated that only half of nodes have pressure within the desired limit of 10–70 m of water; the remaining 45.11% and 4.51% of the nodes have pressure above and below the desired limit of pressure, respectively, at average daily demand. At peak hour demand, the nodes with pressure within the desired limit reduced to 34.3%. The analysis of pipe velocity showed that only 45.71 and 48.57% of pipes have a desired limit of velocity (0.5-2 m/s) at average daily demand and peak hour demand, respectively. The extended-period simulation showed 45.36% of the nodes to have pressure within the desired limit, whereas 51.88 and 3.76% of nodes had pressure above and below the desired limit, respectively. However, 62.86% of pipes had less than the allowable velocity limit for the extended period. By applying pressure-reduced valves, it was possible to keep 99% of the nodes' pressures within the desired range. Even though there are water interruptions, the customers’ satisfaction with the existing water supply service is 55.4%. To provide reliable water supply service, utility officials need to work on modified network by involve community for its sustainable management.

Keywords: Customers Perceptions, Dukem Town, Hydraulic performance, WaterGEMS, Distribution Networks