The world is rapidly drawing down the natural water reserves that have traditionally protected communities against drought and water shortages, with the United Nations warning that groundwater and glaciers are being depleted at an alarming rate.
The warning was contained in the latest State of Global Water Resources report of the World Meteorological Organization (WMO), as reported by Channels Television on Thursday.
WMO Secretary-General Celeste Saulo said the decline in what she described as the planet’s “slow reserves” was particularly worrying because groundwater and glaciers act as a buffer during periods of drought and reduced rainfall.
“They have served as a buffer that absorbs bad years so that a single drought or a single dry season does not translate directly into a water crisis,” Saulo told reporters, according to the report.
But she warned that the reserve is now being steadily consumed. “We are depleting that savings account,” she said. “We are spending our reserves.”
The WMO report found that global freshwater storage, including groundwater, lakes, rivers, soil moisture, vegetation, ice and snow, continued its decade-long decline, with glaciers shrinking across all regions in 2025.
It said glaciers recorded their fourth consecutive year of significant ice loss, with an estimated 1,400 gigatonnes of water lost globally between 2023 and 2025. The volume is roughly equivalent to the water needed to fill 560 million Olympic-sized swimming pools.
Groundwater is also showing signs of growing pressure, with Saulo saying nearly two-thirds of monitored wells worldwide recorded conditions outside their historical norms in 2025.
The deterioration of these longer-term reserves is occurring alongside increasingly unstable weather patterns. The report said 2025 was among the driest years for the world’s rivers in more than three decades, despite being one of the warmest years on record.
The WMO also warned that the emerging El Niño pattern could intensify the volatility, potentially producing sharper swings between excessive water and severe shortages.
The findings point to a growing challenge beyond individual floods or droughts: the gradual depletion of the natural reserves that have historically helped societies absorb the impact of extreme water conditions.
