The world’s rivers are drying up as climate change worsens and the demand for water increases, the BBC reports. Researchers studying 925 major waterways—from the Ganges to the Colorado—found significantly less fresh water flowing into oceans in 2004 than 50 years earlier. If the trend continues, the growing global population could face shortages—with dire results.
Human activity, such as dam-building and water diversion for agriculture, are responsible for much of the reduction, noted the study, which also pointed to the effects of changing rainfall patterns and increasing evaporation. The only rivers that saw an increase in flow were in parts of the Arctic and Asia, likely due to melting glaciers.