Role of water security for economic development – concepts and global scenarios

We define water security as current and future access to sufficient water resources for productive uses and economic growth. At withdrawal levels in excess of 40% of available water resources, countries or river basins are considered water scarce, and thus water insecure. We find that in 2010, 36% of the world’s population, 39% of global grain production, and 22% of global GDP are at risk due to water stress. Moreover, under Business-as-usual (BAU), that is, if current policy and investments continue, more than half, or 52% of the global population, 49% of total cereal production, and 45% of GDP will be at risk due to water stress by 2050 with withdrawal levels above 40% of renewable resources. Water and food security are closely interlinked: increased water security also improves global food security and vice versa. As irrigation is, and will remain, the largest single user of freshwater withdrawals, large gains in water security can be made from small water savings in irrigated agriculture. However, productivity improvement in domestic and industrial sectors can also make important contributions in reducing the share of population and GDP at risk of water scarcity and should continue to be pursued.