PERFORMANCE EVALUATION OF GOLDA SMALL-SCALE IRRIGATION SCHEME IN ASSOSA WOREDA, BENISHANGUL GUMUZ REGIONAL STATE, ETHIOPIA

Abstract

Evaluation 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 measures