Groundwater is an essential source of freshwater, accounting for about 30.1% of the world’s available freshwater. However, groundwater resources are being rapidly used up at an alarming and unsustainable rate in many areas of the world. A recent NASA study concluded that 21 of the largest 37 aquifers in the world have exceeded sustainability tipping points and are being depleted. Here are some important facts about the world’s groundwater that you should know.

Nearly 50 percent of people living in the United States get their drinking water from groundwater. But its biggest use is irrigation.
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About 27 trillion gallons of groundwater are withdrawn for use in the United States each year.
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30 percent of the Kansas portion of the Ogallala Aquifer has already been pumped out, and another 39 percent will get used up in the next half-century at existing rates.
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According to NASA satellite data 13 of the largest 37 aquifers in the world are considered significantly distressed.
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Underground aquifers supply 35 percent of the water used by humans worldwide.
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An estimated 20 percent of the world’s population depend on crops irrigated by groundwater.
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California is currently tapping aquifers for 60 percent of its water use as its rivers and above-ground reservoirs dry up, a steep increase from the usual 40 percent.
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Roughly 2 billion people rely on water supplied from underground aquifers as their main source of freshwater.
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The world’s most overstressed groundwater source is the Arabian Aquifer System, which supplies water for more than 60 million people.
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Some areas of Mexico City are sinking as much as an inch per month due to groundwater depletion underneath the city.
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Scientists have estimated that northern India, which includes the nation’s breadbasket of wheat and rice production, is depleting groundwater at a rate of 54 billion cubic meters per year.
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The water table under Beijing has dropped by nearly 1,000 feet since the 1970s.
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