The world has entered a dangerous phase: As much as 70 percent of freshwater supplies are in crisis, and some cities have experienced “Day Zero.”

The world has entered a dangerous phase of “global water bankruptcy” that is already affecting billions of people and threatens to destabilize societies, a new United Nations report warns.

Overconsumption, pollution, and the climate crisis have pushed many water systems to a point of no return, with the consequences already being felt through shortages, conflicts, and mass migration.

The report’s lead author, Professor Kaveh Madani, emphasized that many societies have been using water for decades faster than it can be naturally replenished. Rivers, soils, and aquifers are being depleted, while long-term reserves in wetlands and underground layers are being permanently destroyed.

“Many critical water systems have already gone bankrupt, and no one knows when the entire system could collapse,” Madani warned.

According to the report, as many as 75 percent of the world’s population live in countries classified as water-insecure or critically water-insecure. Around two billion people live in areas where land is subsiding due to excessive groundwater extraction, a phenomenon visible in cities such as Mexico City, Jakarta, and Tehran. In Iran alone, the city of Rafsanjan is sinking by up to 30 centimeters per year.

The climate crisis is further worsening the situation through the melting of glaciers, which serve as key natural water reservoirs. Major rivers, such as the Colorado in the United States and the Murray–Darling system in Australia, increasingly fail to reach the sea, while half of the world’s largest lakes have shrunk since the early 1990s.

Agriculture, which consumes about 70 percent of the world’s freshwater supplies, lies at the center of the crisis. More than half of global food production takes place in areas where water resources are declining or unstable.

Cities around the world, including Cape Town, São Paulo, and Chennai, have already faced “Day Zero” scenarios, when drinking water reserves were nearly exhausted.

“Water shortages in India or Pakistan do not affect only local populations, but also have an impact on the global food market,” Madani stressed.

The UN report calls for a fundamental “reset” in how water is used and protected, from reducing water withdrawal rights to transforming agriculture and industry through more efficient irrigation and less wasteful systems. Particular emphasis is placed on supporting communities whose ways of life will inevitably have to change.

UN Under-Secretary-General Tshilidzi Marwala warned that water bankruptcy is becoming a powerful driver of fragility, displacement, and conflict.

“Equitable water governance is essential for preserving peace, stability, and social cohesion,” she said.