Estimation Of Water Loss In Water Supply Distribution Network: A Case Study In Gondar Town

Abstract

Leakage in water network pipes is a major problem that hinders the water industry. Quantifying and characterizing water loss and leakage in a city water supply system is by its nature a complex task. Leakage identification needs detailed field investigation sometimes using sophisticated equipment. In this study, an attempt is made to evaluate both the water supply coverage and the water loss with the available primary and secondary data that was not particularly designed for this purpose. Reduction of non-revenue water is one of the major challenges facing many water industries in Ethiopia in general and particularly Gondar Town water supply utilities as well. So, the study focuses on the estimation of water loss in water supply networks in Gondar Town by using statistical analysis, Water Audit, and WaterGEMS V8i software’s. A statistical analysis was applied to analyze the current water supply coverage of the town. Water audit software was used to analyze water loss components and the efficiency of the system was evaluated using different performance indicators. WaterGEMS V8i (Select Series 6) software was also used to simulate and calibrate the distribution water supply network. Discussions were made with local experts’ to support the quantitative analysis. From the result of the analysis, it was observed that the total water loss in Gondar Town water supply system reaches up to 25.27% of the system input volume in average in the last ten years and 20.29% of the system input volume in which about 13.08% of the total system loss is real losses and 7.21% are apparent lossesin the year 2015. Besides, the average daily per capita water consumption of the town is 25.53 liter/person/day. In general, the low water supply coverage of the town was highly influenced by the availability of water. However, the main reasons for the high loss of water in the entire city water supply network system are the present way of water network maintenance and insufficient financial resources of the utility. Thus, it is necessary to identify the losses encountered in the water supply system so as to take remedial actions in reducing the water loss more significantly