Abstract:
Watershed is considered to be the ideal unit for management of the natural resources.
Extraction of watershed parameters using (GIS) and use of mathematical models is the
current trend for hydrologic evaluation of watersheds.
The aim of this thesis is to oversee the effect future water resource development projects on
the Baro watershed using SWAT models to assess water availability and WEAP mo dels in
assess the water demand of the study area.
The SWAT model was calibrated and validated for measured stream flow at Baro near
Gambela gauging stations. The calibration and validation result showed that model
performance evaluation statistics (coefficient of determination (R
2
) and Nash-Sutcliffe model
efficiency (ENS)) were in the acceptable range (R
2
=0.76 ,E
NS =0.72 for calibration and
R
2
=0.7,E
NS=0.63 for validation). This indicates that the observed values show good
agreement with simulated flow value. In this study the watershed yields average annual
surface runoff of 425.07 mm.
Using WEAP, this study investigated the trend of supply and demand in Baro catchment . The
assessment model is computed based on two scenarios, Scenario1: Irrigation project
development and Scenario 2: Extended Dry Climate condition, in order to see how Baro
watershed responds to the supply of water resources. Based on the result, there will be unmet
demand in the years (2033-2034 and 2044-2045 for scenario 1) and (2033-2050 for scenario
2). The study area tends to experience more water scarce problem in the second scenario;
―Extended dry climate sequence‖ starting from the year 2033. there for a better water resource
management should perform to overcome this shortage.
