The world's most rapidly declining groundwater

Spain, Iran, China and Chile are among the world’s hot spots for the most rapidly dropping groundwater levels in the 21st century, according to a new analysis of 1,700 aquifers in 40 countries. Six California basins rank in the top 100 for the biggest rate of decline. About 12% of the aquifers studied showed losses of more than 20 inches a year.

Median annual change in groundwater basin levels (meters):

1m or more gained

0.25m to 1m gained

Between 0.25m gained or depleted

0.25m to 1m depleted

1m or more depleted