New research identifies global decline in groundwater

San Joaquin River, near Fresno, in Southern California's Central Valley © Steven Kelly / Unsplash

Researchers have analysed the in-situ groundwater-level trends of 170,000 monitoring wells and 1693 aquifer systems in countries that encompass approximately 75% of global groundwater withdrawals. In a paper published in Nature, they report that groundwater-level declines have accelerated over the past four decades in 30% of the world’s regional aquifers.

This widespread depletion in groundwater highlights the need for urgent action. However, this analysis also highlights cases where depletion trends have been reversed due to changes in policy, managed aquifer recharge and surface-water diversions, demonstrating the potential for depleted aquifer systems to recover if managed carefully.

This study of in-situ groundwater-level trends adds to the observations of aquifer systems made by GRACE satellite observations, which may not be able to detect smaller examples of aquifer stress.

It is hoped that by combining these data to exploit the high spatial resolution of monitoring well networks and the global coverage of GRACE and hydrologic models may help to increase understanding of the causes, consequences, and spatial patterns of groundwater depletion.

For more details, see: https://www.nature.com/articles/s41586-023-06879-8