PERFORMANCE EVALUATION OF HALABA KULITO TOWN WATER SUPPLY SYSTEM, SNNPR, ETHIOPIA

Abstract

Safe and adequate delivery of water to a consumption node is an essential function of water distribution network. However, throughout the world especially in developing countries, urban water supply distribution network evaluation is inadequate to transfer available water to a consumption node. Therefore, this study aims at the study of evaluation of urban water supply distribution network with hydraulic parameters performance of Halaba Kulito Town water supply distribution network project as the case study. The methods used to carry out this research were desk study to evaluate previous designs, field data collection and data analysis. For conducting this study, both primary and secondary data were collected and hydraulic modeling software such as Bentley WaterGEMSv8i, ArcGIS version10.1, Geographic positioning system Garmin72 (GPS), EndNote program and other relevant materials were used. The study was carried out by selecting pipes having diameter greater or equal to 50 mm in diameter. The simulated result for both steady state and extended period simulation showed that the performance of distribution system related to pressure 48% for pressure value (< 15 mH2O), 48% for pressure value between (15 - 60) mH2O and 4% for pressure value (> 60 mH2O) pressure head and the velocity of pipe flow showed that 50% for velocity (< 0.6 m/s), 48.8% for velocity range (0.6 - 2 m/s) and 1.2% for velocity (> 2 m/s). Those problems are resulted from incorrect nodal placement and improper pipe connection during designing the system and when expanding the network to the newly established settlement area. The low pressure zone areas around Halaba Kulito Poly Technic College and below and above Halaba Kulito Hospital did not get water at these junctions during peak hour demand. The per capita domestic water consumption of study area was found to be 16 l/c/d in the year 2019. The minimum quantity of domestic water required in urban area of developing country in the radius 0.5 km taken as 20 l/c/day. Regarding to this value, the domestic water supply of Halaba Kulito Town only satisfies 80% of the standard value and the quantity of domestic water required in urban areas of Ethiopia is taken as 50 l/c/d. According to this value, the domestic water supply of Halaba Kulito Town satisfies only 32% of the standard value. The total loss of water in the Town for the year was 219409 m3 and approximately 31.4% of the total production. This figure is lower compared with the average for developing countries (35%). The average the amount of water, which actually reached the consumers (the system efficiency) accounts for only 68.6% of the total water produced. Finally, the researcher recommends preventive measures of interruption of water supply network using control valves, scheduling and installing storage distribution balancing tank above the Halaba Hospital and installing additional water sources for delivering enough and sufficient amount of water to the customers