Blue and green water security assessment of Karuvannur watershed

Abstract Water security is referred as the availability of sufficient amount of good quality water to cater all ecosystem services with a tolerable level of water related risks; whereas water scarcity is defined as the ratio of water demand over water availability which is an indirect indicator of water security [1]. In order to assess the water security in terms of its specific use and availability, it is classified in to blue and green water. For this, the various components of blue and green water are calculated and water security in terms of blue and green water is assessed separately using ArcSWAT software. The crop water requirement is assessed using CROPWAT model. It is observed that in the study area, both blue and green water is secure in the current scenario but green water is less secure when compared to blue water. Therefore more attention is to be given for the conservation of green water in the study area. Since the scarcity value shows an increasing trend, stringent measures are to be initiated for water conservation henceforth, in order to assure a sustainable water security in the coming future.