Institute of Technology
Permanent URI for this communityhttps://etd.hu.edu.et/handle/123456789/66
The Institute of Technology focuses on education, research, and innovation
in engineering, technology, and applied sciences to support sustainable development.
Browse
3 results
Search Results
Item PERFORMANCE EVALUATION OF GOLDA SMALL-SCALE IRRIGATION SCHEME IN ASSOSA WOREDA, BENISHANGUL GUMUZ REGIONAL STATE, ETHIOPIA(Hawassa University, 2019-10-27) MINIEBEL FENTAHUN MOGESEvaluation of the performance of irrigation schemes helps to know the present status of the scheme and to apply possible measures for improvement. Golda small scale irrigation scheme was found in Assosa, Benishangul Gumuz regional state, Ethiopia and had a service of six years. The performance of Golda Small Scale Irrigation Scheme had not been evaluated before this study. Therefore, this study was conducted to evaluate the scheme by considering water delivery performance, on field water management performance and organizational setups and their performance for irrigation water management and maintenance. Primary data collected through field measurements and household field survey, and secondary data from different sources were used. Water delivery was evaluated by external indicators such as conveyance efficiency, relative water supply and relative irrigation supply. Both internal and external indicators were used for evaluating on field water management performance. The internal indicators were application efficiency, storage efficiency, distribution uniformity and deep percolation ratio. The external indicators like agricultural out puts, physical and financial indicators were used. The result of conveyance efficiency, application efficiency, storage efficiency, distribution efficiency and deep percolation ratio, were 53%, 51.6%, 91.6%, 80.76% & 40% respectively. The value of relative water supply and relative irrigation supply were 1.6 and 1.2 respectively. The result of output per unit command area, output per unit irrigated area, output per unit water supply and output per unit water consumed were 3542.66US$, 4306.76US$, 1.42 and 0.69, respectively. The result of the physical indicators, which were irrigation ratio and sustainability of irrigated area, were found to be 0.82 and 1, respectively. Around 54% of gross return on investment was obtained.. About 67.6% of respondents reflected the maintenance condition of the irrigation scheme was bad. Unfair distribution of water was due to water scarcity and illegal water users as the beneficiaries responded. Generally, the scheme requires improvement measuresItem GROUNDWATER FLOW MODELING AND ASSESSING THE IMPACT OF FERTILIZERS ON GROUNDWATER QUALITY: THE CASE OF HORMAT-GOLINA SUB-BASIN, AWASH BASIN, ETHIOPIA(Hawassa University, 2019-10-23) MENGESHA TESFAW ABAYGroundwater is the source of water supply for different purposes including domestic, irrigation and depending on its capacity, it is suitable for industrial activities. Groundwater in many parts of the world is under risk because of increasing demands, mismanagement and contamination. All previous studies had not been explored the predicted groundwater flow dynamics in relation to climate change and anthropogenic stress, but this study has developed on the groundwater fluctuation with respect to human pressure and climate change. Visual mod flow flex 5.1 was used for simulating the groundwater flow in response to different stress periods. Groundwater flow and transport modeling in this Sub-basin have provided information about groundwater quantity as well as the quality aspect for decision makers about the groundwater accessibility. The initial head measured values in before and after irrigation season has varied to a maximum of 0.8 m. The groundwater head level in before and after irrigation season was varied from 9.3 m to 8.26 m in the Southern boundary and from 41.5 m to 38.83 m in Northwestern boundary of the Sub-basin respectively. While the predicted groundwater head and drawdown of increased pumping rate with decreased recharge rate scenario was magnify the bad effects in the Sub basin. The maximum depth of 0.27 m and 2.6 m drawdown was found in before and after irrigated season around the pumped wells respectively. The increased pumping rate with decreased recharge rate was replied to the groundwater head at the end of 2021has decreased by 2.81 min the Northwestern boundary of the Sub-basin as compared as using constant pumping rate with constant recharge rate. While decreased pumping rate with increased recharge rate was replied to the groundwater head at the end of 2021has increased by 2.23 m in the Northwestern boundary of the Sub-basin as compared as using constant pumping rate. The impacts of climate change and human pressure on groundwater have been the greatest threats in those supply wells. Decreased in pumping rate with increased recharge rate has accomplished to restore and protect the groundwater resources which is the best option for groundwater restoration and monitoring. Anthropogenic pressures including the application of fertilizers were a considerable cause of degraded groundwater quality in relation to Nitrate and Phosphate concentration with series of time. The groundwater quality has deteriorating with the applied Urea and DAP fertilizes in the selected wells of Hormat-Golina Sub-basin. Farmers have encouraged using practices that minimize the risk of groundwater pollution by carefully controlling and timing of the use of fertilizers to avoid over application.Item COMPARATIVE EVALUATION OF ELA AND LINTALA SMALL SCALE IRRIGATION SCHEMES, WOLAITA ZONE, SOUTHERN ETHIOPIA(Hawassa University, 2018-07-25) ISRAEL KASSA KUMAIrrigation schemes are usually constructed to deliver service on the assumed efficiency. Due to the schemes’ age and management practice, service rendering status of schemes may be below assumed performance level. Non- operational parts of the irrigation schemes were commonly seen in the study schemes. Therefore these study schemes were evaluated with the help of internal and external performance indicators. Internal performance indicators were conveyance efficiency, application efficiency, irrigation adequacy and uniformity. External performance indicators were water delivery performance and water productivity. Water delivery parameters used were Relative Irrigation Supply, Relative Water Supply, and Water Delivery Capacity. The water productivity of the schemes was also compared with respect to the irrigation water used. Conveyance efficiencies of Ela and Lintala schemes were 86% and 81%, and also Irrigation application of these schemes were 55% and 42%. So that, system efficiencies of Ela and Lintala small scale irrigation schemes were 47% and 34%. So that in Ela irrigation scheme water management in the field was better than Lintala scheme. Also Storage efficiencies in Ela and Lintala plots were 86% and 81%. So, in irrigation time, selected plots acquired the required irrigation depth fairly. And calculated Irrigation uniformity in these plots were 88% and 77%. In Ela irrigation scheme, Relative water supply and Relative irrigation supply was in the interval 0.95-1.96 and 0.94-2.4. In these intervals the lower values 0.95 and 0.94 were obtained in the month February. This revealed the scheme water delivery performance couldn’t answer ETc of the crops in driest month. But its water delivery capacity of main canal was 3.8. So Ela scheme canal capacity was not constraining factor for croping intensity. The Relative water supply and Relative irrigation supply of Lintala was in the intervals 2.53-3.73 and 2.8-4.5. And also its main canal capacity was 2.2. So that this scheme water delivery performance was enough to answer the ETc of the crops. In existing water management, average irrigation water productivity of maize in Ela and Lintala plots was 0.89 and 0.52 kg per m3 of irrigation water reaching the farm.