Abstract:
Unlike most other river basins in Ethiopia, the water resources of the Awash
River have been highly developed and utilized over the last five decades.
Development, particularly of irrigation, continues today. A number of major
irrigation projects are currently being built, designed or planned and it is very
essential to estimate the availability of water.
This research aims to optimally allocate the water in the Upper Awash irrigation
schemes, and recommend a 10-day water release rule for two scenarios. It also
determines the frequency of deficits in the supply of water to irrigated areas
(existing and planned). The thesis compiles recent studies in the basin and
meteorological, hydrological and demand data for each irrigation schemes were
considered for the analysis. Water Evaluation and Planning System (WEAP) model is used for the study for
optimal allocation of the river water based on equitable distribution of water.
WEAP strives to maximize supply to demands sites, subject to all constraints and
priorities.
Rule curve of Koka Reservoir is developed for two scenarios. Thus the result
shows for the second scenario that is from year 2017 the shortage seriously
affect the farm which means some of the irrigation schemes will not get water at
all nearly for seven irrigation consecutive ten days. Hence in order to supply the
limited quantity of water during deficiency, rule is developed on 10-day bases for
optimal water allocation.
