Determining economic depth of agricultural well in sprinkler irrigated farms in Qazvin plain

Decline of groundwater level in many plains of Iran has been accompanied by increase in energy consumption for pumping out water for irrigation. Long this line, a determination of the economic depth of wells, as related to pumping costs, crop value and other costs of agricultural expenditure is indispensable. This study was aimed at determining the economic depth of wells as applied in sprinkler irrigation considering two subsidized vs. non-subsidized energy costs, drilling costs, total cost of agricultural practices and benefit-cost ratio for one as a farmer. In this regard, detailed information, comprised of data from irrigation systems as well as crop yields from Qazvin Plain in year 2011 was used. Under the non-subsidized case, cost of electricity used as energy was much higher than that of diesel fuel. The average income-cost ratio obtained by farmers with electricity used as energy was more than those with diesel fuel under subsidized case, while the reverse was obtained under non-subsidized case. Increasing the depth of the well led to some partial reduction in benefit-cost ratio. The results finally revealed that due to the unusually low cost of energy, there seems to be no limit for drilling to increasing the depth of wells.