Waukesha, Wis., is running out of fresh water.

Located just a few miles from the shores of Lake Michigan, the city of 70,000 wants to use the lake to replenish its quickly diminishing aquifer – a request that has touched off an international dispute.

Thunder Bay Mayor Keith Hobbs wants to protect the lake's already low levels, which he says have affected everything from industry to tourism. But Waukesha officials say they would be withdrawing the equivalent of a teaspoon from a swimming pool.

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Mr. Hobbs believes granting Waukesha's application for access to the lake would set a dangerous precedent and touch off potential water wars. Some news for the mayor: It may be too late. It looks like those wars are coming anyway.

According to Canada's ambassador to the United States, water is the new oil. In a recent interview, Gary Doer said that by the end of the decade, the pressure on water quality and quantity will be immense. He predicted that water debates and disputes between the two countries will make the clash over the Keystone XL pipeline "look silly" by comparison.

It isn't hard to imagine. Many parts of the U.S. are in the midst of a freshwater disaster. Parts of California are experiencing their worst drought in modern history. Some communities are at risk of running out of water within months, a situation that could put new pressure on Canada to export water from the Great Lakes-St. Lawrence River Basin.

But water levels in the Great Lakes have been falling dramatically, which is already having an impact on commerce. For every inch of water the lakes lose, freighters crossing them must lighten their loads by nearly 300 tons. So more ships are needed to transfer the same amount of goods, which adds millions to a shipping company's costs. Any talk of further draining the lakes could incite a revolt among those companies and others – and yet those discussions are almost sure to begin anew.

The U.S. situation is grim. The world's largest known aquifer is the Ogallala, which extends beneath several states, including Nebraska, Colorado, Kansas, Oklahoma and New Mexico. It was formed millions of years ago by retreating glaciers and Rocky Mountain streams. But the Ogallala is no longer being replenished by the Rockies as precipitation declines in the region, some believe as a result of climate change.

Of course, in North America, we've always taken our water for granted. Consequently, overuse of such underground supplies has also contributed to the problems we're now seeing. Water waste has resulted in the loss of more than 40 per cent of the storage capacity in California's government-constructed reservoirs.

It's far from the only state facing shortages. The underground water table in Texas, Oklahoma and Kansas – America's three leading grain-producing states – has dropped by more than 30 metres, according to the U.S. Department of Agriculture.

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In the future, conflicts over water are expected to proliferate around the world. A 2012 intelligence report from the U.S. State Department predicted global water shortages beyond 2022 that could lead to armed conflict and failed states. Water as a tool or target of war or terrorism will increase, the report said, particularly in South Asia, the Middle East and North Africa.

In his Postmedia interview, Mr. Doer listed off a string of potential Canada-U.S. flashpoints, ranging from the St. Lawrence Seaway to Lake of the Woods, which borders Ontario, Manitoba and Minnesota and has seen growing concerns about water quality.

But the most pressing issue is drought. Some hold the view that the moment an ounce of our water is exported south, it will become subject to the provisions of the North American free-trade agreement. And that once that tap is turned on, there may be no stopping it – Canada's water resources will suddenly become a U.S. national security concern.

While that may seem alarmist now, don't rule out the possibility. The pressure on these precious water supplies is growing by the day – just ask Mr. Doer.

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