Assessments of Urban Water Supply Distribution System Challenges (The Cast for Gambella Town Water Supply System)

Abstract

Urban water supply challenges are a common problem in Ethiopia particularly in Gambella region. The production-demand gap and the unsatisfied demand of the town inhabitants were widening from year to year. The overall objective of this study is to assess the challenges of municipal water supply distributions in Gambella town. The Primary data was collected through interview, field survey, and photographs of relevant sites and infrastructures. The secondary data was collected from design documents, literatures, journals and reports. WATERGEMS V8i was used/applied to analysis the collected data. Based on the result, 86.11% of pipes are in the standard velocity range and 13.89% show below the minimum velocity. Based on the actual pressure result,2.78% of junctions are responsible for extremely high pressure during the minimum consumption hour, 5.56% of the junctions are liable to a minimum pressure. The cause of low productivity were found to be; poor hydraulic performance, lack of aluminums sulphate ,lack of man power skill. Pipe leakages, road construction, building construction are major cause of water losses in Gambella town with 51.2% water loss. Existing water supply coverage for the town is 74%.Also there are some kebeles in the town which are out of the reach of distribution pipes and villages with distribution pipes but unavailability of water most of the time due to the fact that design capacity of the system is too low for the current population of the town Gambella. In conclusion, the problems include inconsistent performance of the water supply system; low service coverage by the distribution system and per capita demand; and intermittent mode of water supply due to electric power fluctuation. These problems are related to mainly lack of organized or well managed operation and maintenance of the water supply system; high water losses due to leakages; and inconsistency performance of the electro-mechanical and treatment plant unit. Therefore, it’s recommended that, the water utility need to have immediate respond to maintenance requirement on transmission and distribution main pipes to avoid high loss of water from these pipes. There is a need for a purchase of leakage detector machine like; - Acoustic sensor, Digital signal processing and geographical positioning system mounted meter reader mobile to avoid invisible leakages.