A large contingent of about 500 scientists are warning that most of the planet's 9 billion people will face severe shortages of fresh water within two generations, the result of climatic changes, pollution and the overdevelopment of natural resources.
Scientifically speaking, a generation is about 25 years --- although it used to be considered two decades, 20 years
The scientists, meeting at the Institute for Environment and Human Security of the United Nations University in Bonn, Germany, said in a joint statement the world's water systems are soon expected to reach levels that "could trigger irreversible change with potentially catastrophic consequences," as they called on governments to establish tough new targets for water resource conservation.
The scientists noted much of Earth's freshwater stores are being used faster that they can be replenished, even over several lifetimes, so it's imperative people stop regarding fresh water as an endless resource.
"There is no citizen of the world who can be complacent about this," said Janos Bogardy, IEHS director.
Ban Ki-moon, the U.N.'s secretary general, followed the joint statement by asserting, "We live in an increasingly water insecure world where demand often outstrips supply and where water quality often fails to meet minimum standards. Under current trends, future demands for water will not be met."
A majority of the earth's population - about 4.5 billion people - already live within 31 miles, or 50km, of a so-called "impaired" water resource, one that is running dry, or polluted, the scientists said.
For instance, there are an estimated 210 million United States citizens within 10 miles of an "impaired" water source, and that number is only likely to rise.
"These are self-inflicted wounds," said Charles Vörösmarty, a professor at the Cooperative Remote Sensing Science and Technology Center. "We have discovered tipping points in the system. Already, there are 1 billion people relying on ground water supplies that are simply not there as renewable water supplies."
Water supplies face numerous threats, not the least of which are progressively more intense droughts, floods, heat waves and storms initiated by climate change.
Then, so much water has been pumped out from certain underground storage areas that salt water has been able to rush in, therefore rendering the water sources unusable and forcing farmers to move and search for the water they need elsewhere.
Most of the areas where water will be scarcest soonest are in poor countries, which have few if any resources to answer handle the coming water shortages.
Those particular areas are often already plagued with political instability, tension and conflict and the competition for water resources will make those other problems worse.