ASSESSING GROUND AND SURFACE WATER SCARCITY INDICES USING GROUND AND SURFACE WATER FOOTPRINTS IN THE TEHRAN PROVINCE OF IRAN

Water consumption is increasing at an alarming rate all over the world. Iran is currently facing high water stress as a consequence of mismanagement. The aim of this study is to evaluate the agricultural ground and surface water footprints in the Tehran province of Iran in order to establish agricultural ground and surface water scarcity indices. Blue and green water footprints were evaluated based on the water footprint method. The volume at which ground and surface water is generated was obtained via fieldwork and GIS (Geographic Information System) data for the first time. In addition, an indicator for evaluating the agricultural ground and surface water scarcity index was established. The total groundwater footprint for the production of crops in Tehran was half of the total water footprint in 2014-2015. The results showed very high agricultural groundwater stress and moderate surface water stress. Groundwater abstraction for the agricultural sector was more unsustainable than surface water. Besides, agricultural ground and surface water scarcity indices are more suitable than existing indicators because they disclose environmental impact of crops production and help stakeholders to assess groundwater and surface water management policies. The agricultural water footprint should be reduced to sustain agricultural water consumption in Tehran.