Water Resource
Permanent URI for this collectionhttps://etd.hu.edu.et/handle/123456789/71
Browse
3 results
Search Results
Item GIS-BASED SURFACE IRRIGATION POTENTIAL ASSESSMENT: A CASE STUDY IN MUGA WATERSHED EAST GOJAM ZONE, AMHARA REGION, ETHIOPIA(Hawassa University, 2021-10-22) ZELALEM ABEZAAssessing available water and land for surface irrigation is important for planning their use. The high dependency on rain-fed farming and erratic rainfall require alternative ways of improving agricultural production. The alternative to improve is through development of small scale irrigation schemes by assessing the available suitable land and water resources in sub-basin level. The objective of this study was assessing the land and water resources potential of Muga watershed in East Gojjam Zone for surface irrigation development using Geographic Information System. Identification of suitable land, estimation of available river flow, and determination of irrigation water requirement were the main steps that were followed. The land irrigation suitability factors considered were: slope, soil, land use/land cover, and river proximity. Estimation of river flow in the six manually added outlets was conducted by simulation after calibration and validation were carried out with the observed flow of gauged river using Soil and water assessment tool. The commonly cultivated crops in the area maize, onion and potato were selected, and the irrigation water requirements of these crops were determined using the CROPWAT8.0 model. Comparison between gross irrigation water requirement of the selected crops for the identified suitable land with simulated river flow at the area of the selected site was carried out. Overall, the weighted overlay analysis of these factors gave a suitable land among river sub-basin as G/muga 560ha, E/muga 3057ha, Bora 670ha, Gibstawit 404ha, and Genet 241ha. Mean monthly flow of 11.4m3 /s were determined at the watershed. A total of 3443ha (5.1%) was found to be potentially suitable for the development of surface irrigation project from a total watershed area of 67535ha. In conclusion, the irrigation potential of the area could be increased either by harvesting rainwater or using groundwater.Item GIS-BASED SURFACE IRRIGATION POTENTIAL ASSESSMENT: A CASE STUDY OF TEME WATERSHED, EAST GOJAM ZONE, AMHARA REGION, ETHIOPIA(Hawassa University, 2022-03-28) GETNET GUADIEAssessment of available land and water resources for surface irrigation development within watershed level using Geographic Information System (GIS) is important for planning its use. Due to the development of irrigated agriculture is less regardless of its important to alleviate food insecurity and food production problem in the study area, improving of agricultural productivity within the study are needs a quantified irrigable land and potential of water resources through in a systematic and scientific way. Identification of suitable land and mapping to it for surface irrigation, estimation of available flow, determination of irrigation water requirement and Comparing the Gross irrigation water requirement of the selected crops for the identified suitable land with simulated river flow were the main steps that were followed. To identify suitable land, the land suitability parameters like slope, soil (texture, depth and drainage), river proximity, and LULC of the study area were used. Application of weighted overlay tool was used for analysis of these factors to give a suitable land among river sub watershed of Tejatil, G/Teme, Tige Bahar and Tiwa as 578ha, 735ha, 234ha and 955ha respectively, which accounts 13.7% of the total study area. Simulated flow of the four manually added outlets and one linking stream added outlet in the watershed after calibration and validation by considering 12 sensitivity parameters and observed flow of gauged river were conducted. The mean monthly flow of 4.34m3 /s was determined at the outlet of the watershed. Three crops (Tomato, Maize and Potato) were selected to grow on the identified irrigable areas and its irrigation water requirement of these crops were estimating by implementing CROPWAT8.0 model as an input of climatic, crop and soil data .By comparing gross irrigation water requirement of the selected crops for identified irrigable land and simulated river flow at the area of selected site, the total irrigation potential site of the study area for surface irrigation was found to be 555ha, which accounts 3.04% of the total study area. In conclusion, the potential irrigable land is very small due to the scarcity of water. Therefore, the irrigation potential of the area could be increased either by harvesting rainwater and using ground water or by analysis a suitability of other method of irrigation such as trickle/drip and sprinkler irrigation method.Item GIS-BASED SURFACE IRRIGATION POTENTIAL ASSESSMENT OF MEKI RIVER WATERSHED, CENTRAL RIFT VALLEY OF ETHIOPIA(Hawassa University, 2023-07-16) KUFA KAFU MILOIrrigation can contribute to food security by increasing food availability and cash income of smallholder farmers. However, surface irrigation development in the study area is hindered due to lack of reliable data of suitable land and available water potential. Therefore, this study assessed the land and water resources of Meki River watershed in rift valley lakes basin in Ethiopia using Geographic information system to identify suitable land and available water potential for surface irrigation. Land suitability factors such as soil depth, soil texture, soil drainage, slope and land use/cover were considered and their suitability analyzed using ArcGis10.3. Water availability assessed using soil and water assessment tool and calibrated and validated with observed flow. Flow duration curve from monthly simulated flow was developed to obtain the reliable monthly flow at 80% probability. Irrigation water requirements estimated using CROPWAT8.0 for the Maize, Onion and Tomato and compared with dependable flow to compute the potential irrigable area. Regarding evaluation factors the results showed that 52.31 % of slope, 89.9% % of soil depth, 75.95% of soil drainage 99.65% of soil texture and 94.73 % of land use land cover were in the range of highly to marginally suitable, whereas 47.69 % of slope, 10.1% of soil depth, 24.1% of soil drainage, 0.35% of soil texture and 5.27 % of land use land cover restricted for surface irrigation. Further weighted overlay results showed that 177,199 ha were in the range of highly to marginally suitable whereas 35798 ha were unsuitable. Besides, the results revealed that maximum and minimum dependable flow during crop growing period were 39.6 m 3 /s and 0.05 m 3 /s respectively. Moreover, the results showed that irrigation water demands vary from crop to crop, and 4126.04 ha were obtained to be potentially suitable for the development of surface irrigation project. This study concludes that there is huge suitable land and insufficient water availability in the watershed. Therefore, irrigation potential of the watershed can be increased through using water saving technology such as drip, sprinkler and selecting other less sensitive crops, also using other water sources such as Lake Water, ground water and rain water harvesting