Water Resource

Permanent URI for this collectionhttps://etd.hu.edu.et/handle/123456789/71

Browse

Filters

2020 - 20212

Settings

Subject: search.filters.subject.surface water

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    ASSESSMENT OF SURFACE IRRIGATION POTENTIAL IN UPPER WEYIB WATERSHED, GENALE DAWA BASIN BALE ZONE OROMIYA REGION, ETHIOPIA
    (Hawassa University, 2021-03-16) GETACHEW SHIFERAW ESHETE
    Planning and decision-making for new irrigation development projects require the systematic assessment of irrigable land together with available water resources. This study was started with the objectives of assessing the water and land resources potential of the upper Weyib river watershed for irrigation development and generating a geo-referenced map of these resources by using a Geographic information system. Watershed delineation, identification of potentially irrigable land, and estimation of irrigation water requirement and surface water availability of river watershed were the steps followed to evaluate this irrigation potential. GIS was used to map the irrigation potential of the watershed; the ArcSWAT model; was used to estimate the water availability in the watershed; AHP and pairwise comparison was used to land suitability assessment and a CROPWAT model was used to determine the major crop water requirement. To identify potentially irrigable land, irrigation suitability factors such as soil physical properties, slope, land use/ land cover, and distances from the water supply(sources) are taken into account. The irrigation suitability analysis if these factors indicate that 98.59% of soil 75.72% LULC and 41.62%slope in the study area are in the range of highly suitable to marginally suitable for the surface irrigation system. The final results of irrigation land suitability indicate that 14.90% high suitable (S1), 55.08% moderately suitable (S2), 5.62% marginally suitable (S3), whereas 24.38% not suitable (N) for surface irrigation development. After calibration and validation, the observed monthly streamflow values with a coefficient of determination (R) and Nash-Sutcliffe Coefficient (NSE) of 0.81 and 0.77 for the calibration period and 0.77and 0.76 for the validation period, respectively. The Irrigation water demand of the four major crops which are grown in the study area through the growing season was found to be 1170.1mm. Based on the Model Builder of ArcGIS, the SWAT estimated available water can potentially irrigate an area of 10,564.15ha for highly suitable areas
  • No Thumbnail Available
    Item
    SURFACE WATER AVAILABILITY AND SCENARIO BASED DEMAND ASSESSMENT OF THE KELETA RIVER WATERSHED, AWASH RIVER BASIN, ETHIOPIA
    (Hawassa University, 2020-10-25) MEHIRET HONE FISHA
    The ever-increasing world population, changes in the living standard and consumption pattern, and the rapid expansion of irrigation agriculture exert a lot of pressure on water resources. Irrigation, the major water user, relies mostly on surface water from the Awash River and its tributaries and it is very important to assess surface water potential at this basin. This study was conducted at Keleta River Watershed, which is found in the Upper Awash River Basin of Ethiopia. The main objective of this study was to assess the surface water availability and scenario-based water demand assessment in the Watershed using the Soil and Water Assessment Tool (SWAT) and Water Evaluation and Planning System (WEAP) models. The SWAT and WEAP models were used to estimate the surface water availability and scenario base users’ water demands in Keleta River Watershed, respectively. The SWAT model was calibrated and validated using observed streamflow data to get reliably predicted streamflow values. The model performance was evaluated employing two error indices called Nash-Sutcliffe efficiency (NSE) and coefficient of determination (R2 ). The results showed that the mean annual precipitation, actual evapotranspiration, and potential evapotranspiration were 831.1, 451.4, and 1180.4 mm, respectively in Keleta Watershed. The estimated surface runoff available from the entire catchment was 124.50 million cubic meters (MCM), which was equivalent to 165 mm depth of mean annual runoff. The assessment of water demand was done based on the current and projected future scenarios. The identified sectors of water users in the watershed were irrigation, livestock, domestic (rural and urban), public and industrial demands. The scenarios evaluated what would be the water demand if the population growth rate is 4% and the Irrigable area increases by 5% annually in the coming 25 years until 2045. The results showed that irrigation was found the highest water consumer among the demand sites whereas the lowest was observed in the public demand site, which consumed 42.22 and 0.63%, respectively from the total demand. The predicted water demand increases by 83.55% in 2045 while the unmet demand increases from the current volume of 0.25 MCM to 7.65 MCM due to the expansion of the irrigable area as compared to the reference scenario. Generally, the result indicated that the water demand as well as the unmet demand increases in the Kelata watershed. The study shows that the water demands in January, February, March, and April were found to be high as the supply was found to be low during the same months. This indicates the temporal variation of supply and demand in the Watershed. Water harvesting structure and groundwater development should be conducted to supplement this water deficit