A human can live without food for almost a month but survive no longer than a week without water. The UN estimates a person needs a minimum of 50 liters of water a day for drinking, washing, cooking and sanitation. However, over a billion people do not have access to this minimum amount.
According to UNESCO, the world's population is appropriating 54% of all the accessible freshwater contained in rivers, lakes and underground aquifers. If per capita consumption of water resources continues to rise at its current rate, humankind could be using over 90% of all available freshwater within 25 years, leaving just 10% for all other living beings.
Freshwater lakes and swamps account for a mere 0.29% of the earth's freshwater. 20% of all surface freshwater is in one lake, Lake Baikal in Asia. Another 20% is stored in the Great Lakes. Rivers hold only about 0.006% of total freshwater reserves.
Mankind uses only a drop in the bucket of the total available water supply.
So where is all the water?
Antarctica is thought to hold about 75% of the world's fresh water (and 90% of the world's ice). In fact, almost 10 percent of the world's land mass is currently covered with glaciers, mostly in Antarctica and Greenland. But it will take more than a Zippo lighter to melt it for daily use.
For the United States, one crucial source is the huge underground reservoir which stretches from Texas to South Dakota, the 800-mile Ogallala aquifer. It provides an estimated third of all US irrigation water. In fact, 95% of the United States' fresh water is underground.
In Libya, the Great Man Made River Project, as it's called, is pumping some 6 million cubic meters of water a day from aquifers in the desert, providing irrigation for 150,000 hectares of land. Many countries have turned to aquifers to quench peoples' thirst.
Aquifers form over thousands of years, but many had been cut off from their original natural sources and are being steadily depleted. In some areas, like Mexico City, aquifer levels dropped by 3 - 5 feet a year, essentially sinking whole areas.
According to UNESCO, the world's population is appropriating 54% of all the accessible freshwater contained in rivers, lakes and underground aquifers. If per capita consumption of water resources continues to rise at its current rate, humankind could be using over 90% of all available freshwater within 25 years, leaving just 10% for all other living beings.
Freshwater lakes and swamps account for a mere 0.29% of the earth's freshwater. 20% of all surface freshwater is in one lake, Lake Baikal in Asia. Another 20% is stored in the Great Lakes. Rivers hold only about 0.006% of total freshwater reserves.
Mankind uses only a drop in the bucket of the total available water supply.
So where is all the water?
Antarctica is thought to hold about 75% of the world's fresh water (and 90% of the world's ice). In fact, almost 10 percent of the world's land mass is currently covered with glaciers, mostly in Antarctica and Greenland. But it will take more than a Zippo lighter to melt it for daily use.
For the United States, one crucial source is the huge underground reservoir which stretches from Texas to South Dakota, the 800-mile Ogallala aquifer. It provides an estimated third of all US irrigation water. In fact, 95% of the United States' fresh water is underground.
In Libya, the Great Man Made River Project, as it's called, is pumping some 6 million cubic meters of water a day from aquifers in the desert, providing irrigation for 150,000 hectares of land. Many countries have turned to aquifers to quench peoples' thirst.
Aquifers form over thousands of years, but many had been cut off from their original natural sources and are being steadily depleted. In some areas, like Mexico City, aquifer levels dropped by 3 - 5 feet a year, essentially sinking whole areas.
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