Performance Evaluation Of Water Conveyance System Of Kesem Irrigation Scheme: Afar Region, Ethiopia

Abstract

Irrigation development is one of the most key factors considered in many developing countries like Ethiopia to alleviate the poverty and improve the livelihood of the community both in the urban and rural area. Irrigation development in the country, especially where the availability of irrigation water supply is sufficient helps to fulfil the food self-sufficiency by producing more crops than rain fed production of one time per year. Like in Ethiopia, in which the irrigation development is very infant even if the availability of the irrigation water is sufficient, the benefit from the irrigation development is very low due to high loss of irrigation water from the main conveyance of the irrigation canal to the field application area in many irrigation schemes like Kesem irrigation scheme. In line with this the main purpose of the current study was to evaluate the water conveyance system of Kesem irrigation scheme, which was operational since 2009.In the evaluation of the irrigation scheme, different irrigation performance indicators were used for the irrigation canal section from October 2020 to January 2021 G.C.To determine the crop water requirement, crop coefficient at growth stage of crop and reference evapotranspiration water determined by the Penman Monteith Method (CROPWAT 8.0 Model) using climatic data collected from Melka Werer Metrological Station. The irrigation water flow in the main and three secondary canals were measured at different sections of the canals using Current meter. The performance indicators used in this evaluation were water delivery performance, which includes adequacy, equity, dependability and efficiency, and maintenance performance includes water surface elevation ratio, effectiveness of infrastructure, water delivery ratio and sustainability of irrigated area. The result of this study indicated that, the adequacy, performance indicators of the secondary canals-1, 2 and 3were fair at the head section(0.81- 0.91, 0.80-0.89 and 0.81-0.91)respectively, and poor at the tail section of the three secondary canals(0.67- 0.79, 0.70-0.79 and 0.68-0.79) the entire system, respectively. The equity performance of the three secondary canals were ranges from good (0.05-0.09) to fair (0.13-0.14) at head and tail section of the canals. But the maintenance indicators considered in this study indicate as the scheme requires continuous maintenance to improve the overall performance of the irrigation scheme. Therefore, it is recommended to undertake appropriate maintenance activities of conveyance structures of the irrigation scheme that improve the overall performance of the irrigation scheme and that may help for the sustainability of the scheme.