HYDRAULIC PERFORMANCE ASSESSMENT OF HARGEISA WATER SUPPLY SYSTEM, USING WATERGEMS A CASE STUDY OF (IBRAHIM KOODBUR DISTRICT), SOMALILAND

Abstract

Kood Buur district of Hargeisa city in Somaliland using WaterGEMS software. In this research, the data were collected through interviews with key personals of the Hargeisa water agency. Other supporting concern data were, collected from a source like government and non-government organizations, various internet sited. The current average daily per capita consumption of the Ibrahim Kood Buur district was 37.54 l/c/d in the year 2018 and the analysis result of performance indicator shows that the water supply coverage of the district is 41%. Moreover, the Water GEMS can be used to identify the level of pressure in junctions and the level of velocity through the pipe. After, Simulation results for maximum and minimum nodal pressures, flow velocity, and tank level were used as a base parameters to analyze and improve the hydraulic network of the system. The analysis result showed that there were various problems in the existing system and modifying system, which are oversized pipe and undersized pipes related to the minimum flow hours, 25% and 9% of the junctions were below and above the allowable limit. During peak flow hour before modification of the system 47% of the total nodes in WDS are below desirable minimum pressure and after modifying the system is 1.2%. In addition to water pressure, the Flow Velocity in the distribution network before modification 47% of the pipe was below desirable minimum velocity which causes sedimentations. After modifying the system only 4 pipes are below minimum velocity for the whole distribution system. Water audit software was also used to analyze water loss components and the efficiency of the system was evaluated using different performance indicators. Nearly 39% of the total water production is lost at different levels of distribution systems before reaching the consumer. This study concluded that the existing water distribution network in the study area was not adequate to satisfy the required water demand. The existing system can significantly reduce the demand problem by modifying the existing system like changing old pipes and optimizing under and oversized pipes.