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Dozens of the world’s major rivers are so heavily tapped, they often run dry before reaching the sea. More than half of all large lakes are shrinking, and most of the world’s major underground sources are declining irreversibly as agricultural pumping drains water that took centuries or even thousands of years to accumulate.
In a report this week, U.N. scientists warn that the world has entered a new era of “global water bankruptcy” — a term that starkly underlines the urgency of efforts needed to protect what remains.
“For too long, we have been living beyond our hydrological means,” said lead author Kaveh Madani, director of the U.N. University’s Institute for Water, Environment and Health.
Drawing on extensive research, the report says more and more regions of the world are effectively overspending from all their water accounts, and their reserves are dropping. The term “water crisis” is often used locally and globally, but the scientists said that denotes a temporary emergency from which a region can recover, whereas many parts of the world are depleting water beyond safe limits and are now bankrupt or approaching bankruptcy.
Many rivers, lakes, aquifers and wetlands have been pushed past “tipping points” and cannot bounce back, the report says.
“Millions of farmers are trying to grow more food from shrinking, polluted or disappearing water sources,” Madani said.
An estimated 70% of water globally is used for agriculture. Where water resources are exhausted, it can mean collapsing economies, displacement and conflict. The report says about 3 billion people, and more than half of global food production, are concentrated in areas where water resources are in decline.
The scientists said more than half of the world’s large lakes have shrunk since the 1990s. About 35% of the planet’s natural wetlands, nearly the size of the European Union in total, have been wiped out since the 1970s.
Excessive pumping of groundwater has led to long-term declines in about 70% of the world’s major aquifers, and in many areas these declines are causing the land to sink. Land subsidence linked to groundwater overpumping, the report says, is occurring across more than 2.3 million square miles, nearly 5% of the global land area. This permanently reduces what the aquifers can hold and also worsens the risk of flooding.
About 4 billion people endure severe water scarcity at least one month each year.
Water bankruptcy is not only a problem in the world’s dry regions, Madani said. “Like financial bankruptcy, it’s not about how rich or poor you are. What matters is how you manage your budget.”
And in many regions, the water people are using perpetually outstrips the supply year after year, effectively breaking the budget.
The report points to the Colorado River and its depleted reservoirs, on which California and other western states depend, as symbols of over-promised water. Other hotspots of chronic overuse include parts of South Asia, the Middle East and North Africa.
“We must prioritize prevention of further damage to our remaining savings,” Madani said. “By acknowledging the reality of water bankruptcy, we can finally make the hard choices that will protect people, economies and ecosystems. The longer we delay, the deeper the deficit grows.”
Water bankruptcy also is caused by deforestation, loss of wetlands and pollution, the researchers said. These problems are compounded by climate change, which is upending the water cycle and bringing more severe droughts and floods.
The report was released ahead of a U.N. water conference in the United Arab Emirates in December.
Madani also authored a peer-reviewed article this week that presents a definition of water bankruptcy, saying the term is a diagnosis to “communicate the severity of the problem and the urgency of a transformative fresh start.”
The banking analogy used throughout the report, he said, points to solutions that are similar to managing a financial bankruptcy — preserving remaining capital while cutting spending.
Solutions for dealing with exhausted water resources will vary by region, Madani said, and will need to account for the reality that “simply taking water away from farmers can mean unemployment, immediate tension, chaotic situations,” and that farmers and others need assistance to use less water and adapt.
In a related study published last year, scientists analyzed more than two decades of satellite data and found that vast areas of the world are losing fresh water and getting drier.
In a recent World Bank report, researchers said global water use “increased by 25 percent from 2000 to 2019, with about a third of this increase occurring in regions already drying out.”
Jay Famiglietti, a hydrologist and professor at Arizona State University, said embracing the term water bankruptcy “is a brilliant way to convey that the water resources have been mismanaged, excessively utilized, and are no longer available for current and future generations.”
He said water experts struggle to find the right “hook” to convey the severity and urgency of the problem, and calling it water bankruptcy promises to catch on.
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Ian James
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