Quantifying the impact of dams on global streamflow over the period of 1985–2014

The number of dams globally has increased dramatically over the past few decades, providing reliable water resources by regulating natural streamflow. However, assessing the impact of dams on natural streamflow at a large scale remains a challenge due to lack of dam storage variation data. Here we analyzed flow regulation by dams from 1985 to 2014 over 153 basins globally using satellite remote sensing data. Two-thirds of global basins are regulated below 10%, and the high degree of regulation is mainly distributed in underdeveloped regions such as Central Asia and East Asia. Only 27% of basins have an increasing regulation trend from 1985 to 2014 and no basins show a decreasing trend. The gross domestic production, climatic water deficit and runoff show significant correlations with the flow regulation. We provide a global scale assessment of flow regulation by dams to support global water resources management.