WATER DEMAND AND SUPPLY ASSESSMENT IN LOWER KULFO RIVER CATCHMENT AREA, SOUTHERN ETHIOPIA

Abstract

Supply and demand assessment in the specific area is important for proper management of water resources. The main objective of this study is to assess and identify the water availability and demand situation in the lower Kulfo River catchment area and to propose appropriate method of water management. The rainfall analysis shows the average annual precipitation of the study area is 837.6mm and from the river discharge analysis the maximum flow is identified to be 71.32m^/sec, the minimum flow of 0.014m^/sec and the mean flow of 6.47m^/sec. The type and amount of water demand is identified and the main water user in lower Kulfo River is for irrigation requirement, domestic use and livestock production. The irrigation requirement is determined by CropWat software for theiexisting crop type and cropping calendar and for the potential Irrigable land In the study area. The water consumption requirement for domestic use and livestock production is estimated according to the standard set by MOWR and IWMI respectively. The study result showed that the irrigation demand Is high in the area and the available water based on 75% and 80% dependable flow Is enough for satisfying the irrigation water requirement for the existing condition and total water demand requirement (i.e. for irrigation, domestic and livestock). For the potential irrigable land in the study area and for the forecasted population and livestock water requirement after 10 years the water deficit is seen on the dry period of the year from November to March. Therefore, the main problem in the area for the present condition, which leads water shortage for the downstream users and at the tail end of the field, is water management due to diversion of river water, conveyance and distribution among "the users, then appropriate mitigation methods are suggested to avoid the problem in the area. •