WMO says 2025 was one of the driest years for rivers in 35 years

Rivers in 2025 had one of the three driest years recorded in the last 35 years, the World Meteorological Organization said on Thursday, 17 September, in its State of Global Water Resources report. Below-normal discharge covered 36 percent of the world’s river basin area. For the seventh year running, basins with historically normal flows were in the minority.

WMO Secretary-General Celeste Saulo presented the assessment in Geneva. She said the pattern is not a single bad year. It is a decade-long signal. Fast parts of the cycle, rain, river flow and soil moisture, still swing with the weather in days or weeks. The slow reserves, groundwater and glaciers, are falling at the same time. Saulo called those reserves the planet’s savings account and said they are being spent.

Ice and wells

Every one of the 19 glacier regions lost ice in 2025, the fourth consecutive year of global loss. Wayne Jenkinson, WMO’s director of hydrology and cryosphere, said 2025 ranked among the three worst years on record in Central Asia, Iceland, the Russian Arctic and western Canada and the United States. Glaciers shed about 408 gigatonnes of ice in 2025 alone. From 2023 to 2025 the cumulative loss was about 1,400 gigatonnes, roughly a third of the freshwater the world withdraws in a year, or the volume of 560 million Olympic pools.

Jenkinson warned that smaller glacier systems in Central Europe, the Caucasus and western North America may already have passed “peak water,” the point after which meltwater declines rather than rises. Nearly two-thirds of monitored wells sat outside their historical range in 2025. Land-surface water storage has fallen over the past ten years.

Asia and Africa accounted for at least half of recorded water extremes over the past five years and more than 80 percent of the associated deaths. In 2025 a compound of cyclones and a heavy monsoon killed up to 3,600 people across Sri Lanka, Pakistan, Viet Nam, Indonesia, Thailand, Malaysia and the Philippines. Nigeria flooded for a second year. The Democratic Republic of the Congo flooded for a third.

The El Niño overlay

Saulo pointed to the El Niño now under way, which WMO expects to be the strongest in four decades of comparable records. That pattern tends to dry some basins and flood others. It arrives on top of rivers that already spent 2025 too low, and on top of glaciers and aquifers that no longer refill on the old schedule.

WMO said water data coverage has improved and that gaps remain in the hardest-hit regions. The report is an annual product. The 2025 edition will go into the briefing papers for next year’s UN water meetings. The operational question it leaves with governments is not a slogan about the cycle. It is whether drought plans, dam rules and glacier early-warning systems are built for a seventh year of abnormal rivers, not for a return to the 1991 baseline.

The numbers that travel from this report are short. 2025 among the driest river years since the early 1990s. Seven years in which “normal” flow is the exception. 1,400 gigatonnes of glacier ice gone in three years. Two-thirds of wells off their historic mark. Those figures will be cited in farm ministries and city water offices long after the press conference in Geneva is over.