Evaluation of modern irrigation systems based on economic water productivity and irrigation efficiency indices in Qazvin province

Regarding to high importance of water as an economic input in agriculture and limitation of common irrigation efficiency evaluation methods, evaluation of irrigation systems with economic indices has high priority. The general goal of this research was study of usual irrigation systems in Qazvin area in the base of economic efficiency indices. In the field of economic efficiency, there is no comprehensive research and there is an undeniable necessity for research in modern irrigation systems development in comparison with traditional irrigation systems. This study can help us in planning of modern irrigation systems development. Focus of this study was on evaluation of 42 modern irrigation systems. Among the sprinkler irrigation systems, average of benefit–cost ratio was 1.4 and this index was 2.94 for drip irrigation systems. Hence, both of these systems are beneficial in the area. Drip irrigation systems are more profitable than sprinkler irrigation systems. Average of benefit per drop for crops products such as wheat, corn, maize, barley and alfalfa were 8333.6, 4854.6, 2486, 6685.8 and 4404.5 Rial per cubic meter, respectively. Also, average of benefit per drop for products such as peach nectarine, grape, apple, pear in drip irrigation system was 34716, 34574, 14975.7, 26503 and 31945 Rial per cubic meter, respectively. Wheat and peach had highest values of benefit per drop index among the studied crops fruits. In this study, 10 sprinkler irrigation systems were evaluated technically and average values of Coefficient of Uniformity (CU), Distribution Uniformity (DU), Application Efficiency of Low Quarter (AELQ) and Potential Efficiency of Low Quarter (PELQ) indices was 76.8, 64.2, 55.2 and 65.3 %, respectively. Results of 5 drip irrigation systems evaluation showed that Efficiency of Uniformity (EU), Application Efficiency of Low Quarter (AELQ) and Potential Efficiency of Low Quarter (PELQ) indices was 65.26, 51.32 and 57.8 %, respectively. Results of this research, showed that In both systems, the benefit–cost ratio increases by increasing the field area. Also, there is high potential for economic water productivity improving in the studied fields. Furthermore, Irrigation efficiency assessment showed the weak condition of irrigation systems operations in the study area.