SUSTAINABILITY ANALYSIS OF URBAN WATER SUPPLY DISTRIBUTION SYSTEM: THE CASE OF JIMMA TOWN, OROMIYA, ETHIOPIA

Abstract

Sustainable access to water supply is central to social and economic development, improving health and educational achievement, reducing child mortality, and improving livelihoods. The main objective of this study is to analysis sustainability of water supply and distribution system by using sustainability index in Jimma town. The primary data were collected from site visit (like identifying water loss trend of the study area) and allocation of water supply distribution apparaturenances while secondary data were collected from Jimma town water supply and sewerage Authority, Oromiya Water Works and Design Supervision and different journal. ArcGIS version10.4.1 for locating the study area, WaterGEMSV8i tool for simulation of water distribution layout and GPS Garmin72 tool for recording of location of water distribution apparaturenances were used. The source of water supply for the study area was surface water (Boye) with yield of 254.63 l/s but only 72.68 l/s of water used due to less pump delivery capacity to service reservoirs. The Maximum Daily Demand of the study area at design period (2040) is 638.59 l/s but, the source only have capacity to yields 254.63 l/s this implies the existing water distribution were not sustainable. The simulated result of existing extended period simulation showed that the performance of hydraulic parameters were the velocity of pipe at maximum flow (at 8:00 AM) showed that 34.25 % for velocity (< 0.6 m/s), 50.46 % for velocity range (0.6-2 m/s) and 15.29 % for velocity > 2 m/s. While the existing simulation were also shows the performance of pressure at minimum flow (at 4:00 AM) with 82.25 % for pressure value (<15 m), 14.71 % for pressure range (15-60 m) and 3.04 % for pressure value (> 60 m) head. Based on the existing simulated result, Resiliency value 0.066 and 0.44, Reliability value 0.15 and 0.505, and Vulnerability value 0.076 and 0.48 were obtained for both pressure and velocity respectively. The overall sustainability index was 0.349 but 0.488 for velocity and 0.209 for pressure. Therefore, the existing water supply and distribution system of Jimma town is not sustainable. To increase the sustainability of water supply distribution system finding additional source of water should be mandatory