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Drinkable water is a precious commodity. Most of Earth’s water is seawater. About 2.5 percent is freshwater—and two-thirds of that is frozen in ice caps and glaciers.

Underground reservoirs are an important source of water supply for many people. Humans use wells to tap renewable and nonrenewable aquifers which quench their thirsts and water crops.

Rivers and lakes contain only a small percentage of Earth’s water—but these surface waters are crucial. Like some aquifers, they are constantly replenished when water moves from atmosphere to Earth and back again through the water cycle.

But surface water sources are subject to variable precipitation patterns that make them notoriously unreliable.

Protecting and managing freshwater sources, above and below ground, is an essential task.

People can’t create more water. But, by managing sources and distribution systems, they can maximize the amount of available water and make the most out of every drop.


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