Assesment of water supply coverage and water loss in distribution system with modeling: a case of Nekemte city

Abstract

Safe drinking water is one of the basic necessities for human beings. However, billions of people in the world have not access to it today. Of this, significant number of the population is from the developing countries especially in sub Saharan countries. A loss in water distribution system is an important issue which can affect water companies and their consumers worldwide. Water losses is categorized apparent loss and real loss and it can be caused by various influences, especially on the pipe networks and are an essential part of the maintenance strategy for existing water distribution networks. The main objective of this study is to estimate the water supply coverage of Nekemte city and the total water loss in distribution system. Water production that is only for the city and the water consumption as aggregated from individual customer meter reading was used to evaluate the total water loss at the city level. Data was gathered using observation, questionnaires, structural interview and the probability sampling technique was adopted in selecting the sample from the population. The systematic sampling techniques conducted to the local communities, consultants, Nekemte Water Supply and sewerage service enterprise and from local Administrative. The result indicates that the city water supply coverage is 48.21%.Out of the total water production 3,050,269.97 Cubic meter per year 1,305,636.97 Cubic meter was considered as loss. This implies 42.69% out of the production was loss before reaching the consumer by different cause specially loss due to pressure and age of pipe. The distribution system model was used to evaluate two alternative scenarios to improve system performance. The objective of the first scenario was to increase the flow rate at taps of low supply by managing pressure and the second scenario aimed at adding taps to parts of the subsystem without easy access to running water. The first scenario was consisted extended period simulation to increase the flow rate at taps of low supply. This scenario was recommended for some parts of the city. The second scenario was hardly recommended to satisfy the community who did not get distribution network still.