Water stress - approaches to quantify overuse of water
Water stress results from an imbalance between water use and water  resources. The water stress indicator in this map measures the  proportion of water withdrawal with respect to total renewable  resources. It is a criticality ratio, which implies that water stress  depends on the variability of resources. Water stress causes  deterioration of fresh water resources in terms of quantity (aquifer  over-exploitation, dry rivers, etc.) and quality (eutrophication,  organic matter pollution, saline intrusion, etc.) The value of this  criticality ratio that indicates high water stress is based on expert  judgment and experience (Alcamo and others, 1999). Read more...