Economic Valuation of Irrigation Water for Large and Small Farm of Wheat (Case Study: Tabas County)

In this research, the average value of marginal production of water in the Tabas County was estimated in 2013-2014 using econometric estimates of agricultural production functions. Data were collected through a questionnaire and random sampling from 100 wheat producers. Five shapes of production functions including Cobb Douglas, Translog Transcendental, Leontief and generalized second degree were estimated using research data. The average production elasticity and marginal production were calculated to be 0.56 and 0.28, respectively. The results indicate that wheat growers are rational producers. The average economic value of water is estimated at 2930 rials per cubic meter, which increases as the size of the farm increase; while wheat cultivators were paying 890 Rials per cubic meter of water in the irrigation network of Tabas in the 2013-2014 crop years. It seems that the difference in the value of marginal production of water with the price paid by farmers, as an important factor, has led to the disappearance of the incentive for farmers to raise funds for increasing irrigation efficiency and the use of new irrigation technologies. An appropriate increase in water supply prices along with implementation of land consolidation has been one of the main suggestions of this study.