Groundwater is Going, Going, Going

A study that was dripped onto readers last week looks into the depletion of global groundwater.

Arid regions where crops are grown extensively were particularly parched from groundwater withdrawal for irrigation purposes.

Farms and households use groundwater as a major freshwater source. Depleting aquifers could have major economic and environmental impacts.

By the numbers: 

• Around 30% of freshwater comes from groundwater
• 170K wells and 1,700 aquifers from 40 countries were included in the study
• ⅓ of aquifers studied over multiple decades have had more severe depletion since 2000
• 71% of aquifers are seeing groundwater on the decline

Where’s the water gone? Researchers say that most places where groundwater levels dropped also saw declines in rainfall over time. Climate variability can impact underground water supplies just like those above ground. Groundwater pumping for irrigated agriculture is also having an impact on supplies.

Some good news: For about 20% of studied aquifers, the rate of depletion has actually slowed down since 2000 compared to previous decades. In some cases—such as the Eastern Saq aquifer in Saudi Arabia and the Bangkok basin in Thailand—policy changes turned the tide on groundwater depletion.