IGRAC Study Reveals Two Decades of Groundwater Level Changes Across 47 Countries

Delft, Netherlands, August 31, 2026 — A new study by the International Groundwater Resources Assessment Centre (IGRAC) has analysed 20 years of groundwater-level measurements drawn from 42,844 monitoring wells across 47 countries, offering one of the most comprehensive global pictures yet of how groundwater resources are changing over time.

Background

Groundwater is a critical resource underpinning drinking water supplies, agriculture and ecosystems worldwide, yet it remains far less visible — and often less monitored — than surface water sources like rivers and lakes. As climate change, population growth and expanding agricultural and industrial demand place growing pressure on freshwater resources, understanding long-term groundwater trends has become essential for water security planning. IGRAC’s study addresses this gap by compiling and analysing two decades of well-level data from monitoring networks spanning nearly four dozen countries, offering policymakers a rare long-term, evidence-based view of groundwater dynamics.

IGRAC is financially supported by the Dutch government and operates under the auspices of the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the World Meteorological Organization (WMO).

Key Findings

The study found that groundwater levels declined in 29 percent of monitored wells over the 20-year period, while 18 percent showed rising levels and 53 percent recorded no clear trend. However, the researchers caution that these global averages can mask severe local impacts — meaning that even where global figures appear stable, specific regions or aquifers may be experiencing significant depletion or other serious consequences.

Drawing on 28 detailed case studies, the research links changing groundwater levels to a range of consequences, including water scarcity, food insecurity, ecosystem damage, land subsidence, contamination and flooding. Specific examples cited in the study include falling agricultural production in Chile and the United States, drying wetlands in Spain and Jordan, and infrastructure damage in Mexico City linked to groundwater-related land subsidence.

Signs of Recovery

Despite the concerning trends identified in many regions, the study also documents cases where groundwater levels have recovered following targeted intervention. In Bangkok, regulation combined with increased surface water supplies helped reduce dependency on groundwater extraction and halt land subsidence that had previously threatened the city’s infrastructure. In parts of India, policy interventions have similarly contributed to recovering groundwater levels, demonstrating that decline is not necessarily irreversible when supported by coordinated regulatory and infrastructure measures.

Conclusion

The IGRAC study underscores both the scale of global groundwater change over the past two decades and the importance of examining local and regional data rather than relying solely on global averages, which can obscure severe localized impacts. At the same time, recovery cases from Bangkok and India offer a measure of optimism, showing that well-designed regulation and investment in alternative water supplies can reverse troubling groundwater trends. As pressure on freshwater resources continues to mount worldwide, the study’s findings offer a valuable evidence base for governments seeking to protect groundwater resources through targeted, locally informed policy action.

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