Analyzing the Sustainability of Urban Water Supply and Distribution System; In Case of Assosa Town Water Supply and Distribution System, Benishangul Gumuz National Regional State, Western Ethiopia (Technical Note)

The main objective of the study is to analysis sustainability of water supply and distribution system of Asossa town. While conducting this research, both primary and secondary data were collected and software such as water GEMSV8i, ArcGIS version10.4.1 and GPS Garmin72 were used. The water supply source of the study area yields 46.1 l/s but only 23.6 l/s of water used. The simulated result of extended period simulation showed that the performance of hydraulic parameters were pressure 21.05 % for pressure value <15 m, 72.8 % for pressure value 15-60 m and 6.15 % for pressure value >60 m head and the velocity of pipe flow showed that 84.86 % for velocity <0.6 m/s, 15.14 % for velocity range 0.6-2 m/s. Based on the simulated result, reliability value 0.728 and 0.151, vulnerability value 0.251 and 0.538 and resiliency value 0.322 and 0.1 were obtained for both pressure and velocity, respectively. The overall sustainability index was 0.375 but 0.19 for velocity and 0.559 for pressure. Therefore, sustainability of existing water supply and distribution system of Assosa town is not sustainable.  It is mandatory to redesign the Assosa town water supply and distribution system in order to make it sustainable.