New publication provides largest ever insight into world’s groundwater depletion rates

A new study was recently published in the Nature journal, regarding the rates of groundwater level change in underground aquifers around the globe.

Furthermore, the study considered millions of datasets from 170,000 monitoring wells and 1,693 aquifer systems in more than 40 countries.

UC Santa Barbara associate professor, and co-lead author of the publication, Debra Perrone, stated that “This study was driven by curiosity. We wanted to better understand the state of global groundwater by wrangling millions of groundwater level measurements”.

Moreover, this attempt brought to light that 71% of the groundwater levels studied were declining in the time period between 2000 and 2022, while 36% of them were doing so at a rate exceeding 3.5 meters per year and 12% of them exceeding 0.5 meters per year.

The research also took into consideration measurements between 1980 and 2000 for 542 of the 1,693 systems, to compare the rate of change to the one observed in the 21^st century.

This analysis found that “long-term groundwater losses are neither universal nor inevitable”, since almost half of the 542 aquifers showed decelerated declines, while some 16% showed decline reversal.

However, the study also showed that roughly 30% of the groundwater level declines had accelerated during the past four decades.

Donald John MacAllister, from the British Geological Society pointed out that such o global compilation of data on the subject had never been done before, especially on this scale.

Finally, the publication points out that reversal of underground aquifer decline is possible, and shows an urgent need for more measures to address it.