灌漑・排水システム工学

This study was conducted to evaluate the performance of organizational arrangement for irrigation water management in Serenta irrigation scheme. The different indicators considered were Water Users Association (WUA) structure, water allocation and distribution systems, water distribution fairness status, conflict management mechanisms in water use, canals cleaning and maintenance performance and organizational support service on irrigation water management. To evaluate the performance of organizational arrangement of the irrigation water management practices, questionnaire survey data collection method was used. The data generated through the household survey were analyzed using SPSS software. Eighty nine per cent of the respondents responded that the organizational performance of the current water users association in the irrigation scheme was poor. This attributed for unfair water distribution system and conflict on water use. To distribute the water fairly among users and to minimize the water loss, water users association should be strengthened and training on irrigation water management need to be arranged for the farmers. This implies that, presence of strong water users association in particular and presence of well organizational arrangement in irrigation water management is corner stone to build an effective irrigation development.

Considering the enlargement of agricultural areas, irrigation efficiency should be increased to obtain the sustainable use of limited water resources. In this study 13 irrigation cooperatives situated in Izmir province of Turkey selected and visited to evaluate their performance. To make this, Data Envelopment Analysis has been used. This analysis is a linear programing technic to determine the relative efficiency of decision making units (DMU) (in this study irrigation cooperatives). In this study, the input oriented DEA model has been used to focus on the efficient use of irrigation water. The objective of the analysis has been to determine where the application of water is the most profitable. While evaluating the performance of cooperatives irrigation water volume (m³) and total irrigated area (ha) have been used as input, and financial agricultural gain (TL) has been used as an output. In addition to this, irrigation water loss of each irrigation cooperative has been calculated by subtracting irrigation water amount from projected water amount by using DEAP software. The results have provided the efficiency scores of irrigation cooperatives and determined which ones have been the most efficient. DEA is a useful analysis to determine irrigation performance of cooperatives situated in Ä°zmir province of Turkey.

This Review Article aims to review irrigation potential of Awash River, opportunities and impacts on the Environment of Awash River Basin. Awash River basin 37 irrigation potential sites are identified out of which 5 are small-scale, 18 are medium-scale, and 14 are large-scale. The estimated irrigation potential is 134,121 hectares. Out of these, a potential, 30,556 hectares are for small-scale, 24,500 hectares for medium-scale and 79,065 hectares for large-scale development. Most of the irrigation schemes in Awash River Basin have good reputation in irrigation efficiency which varies from 30 to 55 %. The Awash River Basin faces land degradation, high population density, natural water degradation, and Salinity and wetland degradation. There should be proper wetland restoration system for the areas such as Becho plain, Borkena swamp affected by water logging and there must be afforestation and soil and water conservation measures for the desertification of middle and lower Awash.