ASSESSMENT OF WATER LOSS IN WATER SUPPLY NETWORK A CASE OF DEBRE MARKOS TOWN

Abstract

Problems in provision of adequate water supply to the rapidly growing urban population in developing cities are increasing dramatically. As a-result demand for additional water sources and infrastructure is growing. Moreover, nearly 50% of the water produced is lost at different levels of the distribution system before reaching the consumers. Debre Markos is one of the developing cities suffering a high shortage of water as well as high water loss. Both financial and technical constraints are the main bottlenecks that hamper the city to satisfy the highly growing needs of its residents . 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 loss and economic level of leakage with the available primary and secondary data. The focus of this study is to assess the total water loss in the distribution network and determine ELL. Water production that is only available for the entire city and the water consumption as aggregated from individual customer meter readings was used to evaluate the total water loss at city level. Pressure readings have been taken at different elevations during the 24-hour durations and an average working pressure was fixed for the determination of real losses in the distribution system. Meter tests of enough samples (according to IWA recommendation) from each brand that were installed for the customers were conducted to quantify the water loss ELL was determined for the system using ECONOLEAK model. Finally, a methodology is suggested to better identify the loss, and remedial actions to be taken by the water supply service office to reduce water loss.