PERFORMANCE EVALUATION OF WATER SUPPLY DISTRIBUTION SYSTEM; A CASE OF JELDU TOWN, OROMIA, ETHIOPIA

Abstract

The aim of proper design of a water supply distribution network is adequately delivering of water to the consumption nodes. However, the hydraulic performance of the water distribution network for this study area was inadequate to transfer available water to a consumption node. Hence, the main finding of the study was to evaluate the water supply distribution system and its hydraulic performance. In order to obtain the main findings of the study, researcher used to, water GEMS v8i for model simulation; Auto CAD v2007i for exporting water distribution networks drawings to water GEMS; ArcGIS 10.1 for extracting junction elevation using geographic positioning system. The existing water supply production is 1693.62 m 3 /day; whereas 811.6m3 /d is currently the maximum demand day. However, the deficit of water supply was observed b/n 2020-2025 years, which requires and hence additional 411.20 m3 /d of waters requires as other surplus source of water. This indicates that the current services of water supply yield are fixed and water demand is timely increasing and attains 3910.7m3 /d at the end of 2040 years (design projection time), hence, 2,217.70 m 3 /d water supplies is requiring end of 2040 as additional sources of supply. This deficit of water supply is proposed for domestic water demand and non-domestic water demand and water loss consideration of all water demand variation. In the same manner the hydraulic performance of this distribution network were simulated at steady state and extended state condition using water GEMS Simulation and there is high junction pressure, negative junction pressure was recorded since simulation at maximum day water demand and minimum day water demand consumption hours. During steady state simulation, 24.60 % of the higher pressures junction of the area, which is ≥70 mH2O, was observed at the different junctions due to low elevation and large pipe diameters. During this condition, most of the distribution pipelines has the optimum range (70-15 mH2O) which is 59.89 % of distribution network is the normal ranges and 15.51 % of the lowest pressure junction ≤15 mH2O due to low elevation and large pipe size. Whereas 51.93 % is the lowest water velocity < 0.56m/s and 13.94 % was the highest water velocity > 2.5m/s recorded with respectively. Since this extended state simulation from the total unfunction junction pressure, due to high pressure and low water pressure is 40.11%. Accordingly, the analyzed of hydraulic performance pressure 0.81 and velocity performance 0.64 and hydraulic performance indexed for both velocity and pressure simulation is 0.47 which ranges in acceptable performance indication according to performance standards