Protecting Water Resources of Tehran Province in the view of Agricultural Water Footprint Index

In recent years, water consumption management mentioned as key topics in the field of water resources management. Tehran province with Tehran city centrality, is considered as main point in water usage. One of the main indicators for using comprehensive watershed management is the water footprint index. In Tehran province the same as other areas, agriculture is the most water consumer. So the aims of this study are water footprint calculation for Tehran’s agricultural products and determine the most desirable county for produce crops and garden crops in water footprint prospective.
In order to calculate the water footprint of agricultural products, using the statistics provided by ministry of Agriculture, counties of the province with the highest production and crop area were identified. In the next step, information such as crops water requirement from the CropWat family software, crop yield and the parameters required in the calculations were calculated and aggregated through agricultural statistics. The water footprint was then calculated using the water footprint index method.
The results showed that in the agricultural production sector, the amount of water contents is far more than garden products. The highest water footprint average was related to wheat (2539 m3 ton-1) and the lowest water footprint average was related to apple (477 m3 ton-1). Comparing the corresponding products among the common counties in the production, it became clear that from the water footprint perspective for crops especially wheat and barley, the southern and western counties of the province which means, Varamin and Islamshahr, have priority over other cities. But for garden products, the Damavand has priority.
In the present study, water consumption for agricultural products analyzed and according to the results, large volume of water resources which are devoted fot the province are used to produce these products in this amount of production and this harvested area. In all of the studied products, green water footprint was more than other water components, indicating the production reliance on rainfall and soil moisture and most of the irrigation water remove from the plant’s reach through water evaporation or penetration. This is due to the fact that a large volume of water is needed to provide drinking water, especially in Tehran, which should protect existing water resources by prioritizing production. In general, it is better to expand only garden crops in Tehran province and provide other crops from outside the city.