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The US is exporting too much of its most valuable resource

However, in the last decade, these wells have begun to dry up. Beyond the estates and family farms, you will see why – thousands of acres of neatly arranged pecans and pistachios, vast fields of alfalfa and corn, huge dairy herds and rows of tomato greenhouses cover the once barren desert. … This vast carpet of industrial agriculture, with food grown for export to various locations around the world, requires deep wells to sustain itself. For every 100 acres or so, a corporate farm owner digs a well up to 2,000 feet deep and draws water from an ancient aquifer at up to 2,000 gallons per second, often 24 hours a day. Drilling rigs often resemble oil rigs.

In Arizona, there are almost no rules governing groundwater extraction. As long as the farms pay the permit fee, they can pump as much as they want.

In addition to over-extracting water from the aquifer, Arizona (along with the American Southwest as a whole) is now experiencing one of the worst droughts in hundreds of years, likely caused by global warming. As the region gets hotter and drier, requiring more extraction from the aquifer, less water is being drawn in from rains or melting snow to replenish it.

What We Don’t Know About The Water Cycle

In school, we teach children about the water cycle, in which water moves from the oceans to the sky, to land, to freshwater pools, and eventually back to the oceans. In this story, the water we use never disappears.

But these tales are silent about something important: the water cycle can take decades or hundreds of years to complete. Most of the fresh water we use every day comes from groundwater, which can take hundreds or thousands of years to accumulate. If we use water faster than we can replenish it, or pollute it and dump it into the seas faster than the natural water cycle can purify it, resources will eventually run out.

If you instead think of water as a final material that is used in much the same way as oil or gas, you will quickly begin to notice its presence in all areas of the economy. For example, over 70% of the water we use goes to food production. But water is also used to make everything from T-shirts to cars to computer chips.

If they can’t find enough water within their boundaries, they think, why not just import it (built into food) from somewhere else?

Like its carbon footprint cousin, the water footprint can be a useful shortcut for understanding a product’s environmental impact – or your own. For example, a cup of coffee has a water footprint of about 140 liters. It takes about 15,000 liters to grow a kilo of beef. For a couple of slices of bread, you can collect 100 liters. A kilo of cotton (say, a pair of jeans and a shirt) can take anywhere from 10,000 liters to over 22,000 liters, depending on where it was grown.

This means that countries and companies are actually moving huge volumes of water across borders by trading in goods. But since the water footprint of food, clothing, or anything else is never recognized in this trade, the movement of water itself cannot be properly regulated.

It is partly for this reason that wealthier countries such as Saudi Arabia and China have begun buying up land in other countries to compensate for the lack of fresh water. If they can’t find enough water within their boundaries, they think, why not just import it (built into food) from somewhere else? The problem is that the places they have been shopping are themselves water-scarce, including sub-Saharan Africa and the Sulfur Springs Valley in southwestern Arizona.

Why Arizona? Because land is cheap and well connected to airports, and because there are almost no rules for water use.

According to Robert Glennon, a law professor at the University of Arizona and one of the nation’s leading experts on water policy, the United States is in fact the largest exporter of water on Earth. Glennon calculated that during the recent severe drought, farmers in the American West used over one hundred billion gallons of water to grow alfalfa, which was then shipped mainly to China.


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