Global - Water Stress Country Ranking - World Resources Institute

Based on the global water-risk indicators from World Resources Institute’s Aqueduct Water Risk Atlas (Aqueduct), a weighted aggregation methodology was applied to bring Aqueduct’s catchment-level information up to the country and river basin scales. This methodology addresses each of the challenges by starting with indicators that were computed within basic hydrological units and assigning spatially explicit weights to reflect the importance of the specific areas based on where water is being used. From these calculations, estimates of the average level of exposure to 5 of Aqueduct’s physical water-quantity risk indicators were generated for all countries and major river basins worldwide. These indicators include (1) baseline water stress: the ratio of total annual water withdrawals to total available annual renewable supply; (2) interannual variability: the variation in water supply between years; (3) seasonal variability: the variation in water supply between months of the year; (4) flood occurrence: the number of floods recorded from 1985 to 2011; and (5) drought severity: the average length of drought times.