HYDRAULICS MODELING AND PERFORMANCE EVALUATION OF KUTABER TOWN WATER SUPPLY UTILITY: ETHIOPIA.

Abstract

Kutaber Town water supply has a lot of problems. The aim of this thesis is to evaluate the hydraulics performance and overall performance of the water supply system. hydraulic performance of the water supply distribution system was evaluated with water Gems and the performance of the utility using International Water Association (IWA) performance indicators were done. additionally, the utility performance in terms of user perception was also evaluated. The existing model analysis results showed significant pressure problems 62% of junctions exceeding the upper limit (70m) and 4% falling below the lower limit (15m). The pipe velocity is from (0 l/sec-3 l/sec) which is out of the standard limit (0.6- 2l/sec). The model calibration was conducted with the field-measured data using Darwin calibration by Water Gems software. The calibration results show a Mean Root Square Error (MRSE) of 2.44, indicating the average error between the observed and simulated values. Additionally, the model has a correlation coefficient of 1:1, demonstrating a perfect alignment between the model’s predictions and the observed data. The optimized network was designed to address the unbalanced network issue, achieving a pressure head ranging from 10m to 81m and maintaining velocities within the acceptable range of 0.21 up to 1.75 l/sec. By User perception, the performance of the town water supply has interruption and water pressure is inefficient, while in terms of water quality the town water supply is good. Also, the utility was evaluated using IWA performance indicators. the average per capita water consumption in Kutaber town is 30 liters per day (l/c/d) which is below the standard limit of 50l/c/d. Finally, the distribution system was modified and optimized by providing alternative connections with pressure reducing valves and changing connection points by zoning to improve the hydraulic performance and reduce pressure variation of the Town