If you saw Syriana you know. Laws get broken, spies tortured, and princes assassinated over oil. Imagine what we’d stoop to if we didn’t have enough of something really important, like water.

And we don’t. As Fortune magazine wrote in 2000, “Water promises to be to the 21st century what oil was to the 20th century: the precious commodity that determines the wealth of nations.” John Hart–CEO of Pico Holdings, a water management company active in Arizona and Nevada and the largest private landowner in Nevada–says on his company’s Web site, “As an asset class it’s near perfect. You’re dealing with an asset that is irreplaceable and critical. . . . I think the investment community is starting to become much more aware of how critical the water issues are worldwide and particularly in the Southwest.”

The Fortune article reported that, according to the World Bank, “one billion people, one-sixth of humanity,” lacked adequate access to clean drinking water, a portion expected to increase to one-third by 2025. Fortune wasn’t writing to sound a humanitarian alarm; it was simply noting the opportunity smart businessmen had spotted to capitalize on the incompetence of some governments at maintaining the local waterworks.

This incompetence isn’t limited to the third world. An article in the December 30 New York Times described Nevada, “the driest state in the nation,” as perhaps one of the most foolish–every day squandering to the mining of gold ten million gallons of water from an aquifer under the northern part of the state. It’s depleting an aquifer that Las Vegas–where three million people are expected to live by 2020, in a desert that receives about four inches of rain a year–is planning to build a $2 billion pipeline to tap.

In Arizona, according to an e-mail sent to me by independent research scientist Alan Christopher, “groundwater reserves are draining at a steadily increasing rate that mirrors the rate of population growth. Even though the groundwater reserves in some areas are enormous, continual pumping eventually drains them. This has already happened at higher elevations in Arizona, where towns are now trucking in water because their wells have run dry.”

Christopher adds ominously, “We in the West discuss ‘solving’ our water problems by building a pipeline from the Great Lakes to Arizona and paying for the water to be diverted here. This, of course, is more of a pipe dream since the Great Lakes Basin has laws preventing this from happening.”

Well, we’re doing our best to write them. In 1998 a Canadian company was given permission by the government of Ontario to ship 158 million gallons of water a year from Lake Superior to Asia in tankers. Thirty U.S. congressmen signed a resolution protesting the sale, and an opposition leader in Ontario thundered, “It’s open season on our clean water.” The province backed down, and the Council of Great Lakes Governors promptly spent $250,000 on lawyers, who concluded that the existing laws offered little protection against predators.

That’s why last month the eight states and two Canadian provinces of the Great Lakes basin signed a compact to raise the drawbridge. You can think of this compact as responsible stewardship. You can think of it as our midcontinent OPEC making sure that the water we control–20 percent of the world’s freshwater supply–stays in our control. You can think of it as the basin guarding against betrayal from within–some staggering rust belt metropolis inking a deal to fill a mile-long tank train.

This much is clear: by the tens of millions, our friends and neighbors are abandoning the rust belt in favor of America’s parched west and southwest. The Great Lakes-Saint Lawrence River Basin Water Resources Compact is the answer now in place when these emigres ask us to save them from themselves.

“Today the economics are not there to say ‘We’re going to take all the water in the Great Lakes and ship it to Phoenix and Vegas,'” Todd Ambs, water division administrator of the Wisconsin Department of Natural Resources, told the New York Times last August. “But water’s not getting cheaper. Twenty-five, 30, 40 years from now, the economics are going to be different. We’ve got to have a system in place to deal with that.”

Hence the compact, which still must be ratified by the legislatures of the eight states and by Congress–no sure thing. You might ask why congressmen from Arizona or Nevada would approve a plan that makes it even harder for their states to cop a share of the lakes’ six quadrillion gallons of water. Would they secretly agree with the Great Lakes guardians who assert that anyone who willingly migrates to the land of cactus deserves his fate? Or maybe they’d calculate that it’s in their best interest to encourage the Great Lakes states and provinces to protect that six quadrillion until the day of reckoning comes, when Hobbesian instincts rule and the compact’s not worth the paper it’s printed on.

Alan Christopher’s dire message to Phoenix is this: stop growing. Not that Phoenix listens. Throughout history, whenever people suddenly recognize that they’ve exhausted the land they live on, their solution is rarely to retrench. Instead they almost always blame their neighbors and try to overrun them. In this case those neighbors are us.

Should the day dawn when the Phoenixes and Las Vegases of America demand the “diversion” of Great Lakes water far beyond its basin, the compact will make it easier to resist. “All New or Increased Diversions are prohibited,” it states bluntly. An exception was written in to accommodate towns and counties that straddle the lip of the basin. Another allows bottled water to be sold beyond the basin. But these exceptions, opposed by Great Lakes absolutists–Nestle spent four years in court defending its Ice Mountain plant north of Grand Rapids and was ordered last month by the Michigan Court of Appeals to scale back the operation–offer no comfort to cactusland.

Here’s what does. “Diversion” is the polite way of saying “taking away and not putting back,” and the compact punts on the mother of all diversions: the Lake Michigan water diverted out of Chicago by way of the Sanitary and Ship Canal, flushed down the Mississippi River, and dumped into the Gulf of Mexico. Confronted with this diversion the compact simply says the U.S. Supreme Court has spoken, in a series of decrees known collectively as Wisconsin v. Illinois. The first decree was issued in 1929–after six other Great Lakes states accused Illinois of draining the lakes–the most recent in 1980.

These decrees permit Illinois (i.e., Chicago) to divert as much as 3,200 cubic feet a second from the Great Lakes basin. That’s much less than the 10,000 CFS flow the old Sanitary District of Chicago, which built the canal, had in mind, but it’s a lot–roughly a third more water than flows each year into the greater Phoenix valley from the Salt, Verde, Agua Fria, and Colorado rivers put together.

Thanks to Chicago, Illinois is the one state in the Great Lakes basin that takes from the lakes and puts next to nothing back. So when Phoenix says to Chicago, “We only want what you’re flushing down the Mississippi,” how does Chicago respond? A cunning Arizona lawyer who tugged on this thread might unravel the compact.

This can’t be allowed to happen. They’ve got the gun, but we’ve got the water. Think of the Great Lakes compact as a citadel, Chicago as the breach in the walls.

Chicago schoolchildren know they live in the place that makes no small plans and that the Sanitary and Ship Canal, which connected Chicago by water to New Orleans, was one of the biggest–a 28-mile trench completed in 1900. They know this triumph of civil engineering, which reversed the Chicago River, saved the city from typhoid, dysentery, and other scourges by sending Chicago’s sewage south and west to the Mississippi instead of into the lake we drink from. These schoolchildren are less likely to know about Wisconsin v. Illinois or that Illinois lost the early rounds of this long legal battle, prevailing in the end only because it compromised on the scale of diversion and ceded control of the canal to the federal government. Few schoolchildren have any idea that before Wisconsin v. Illinois there was Missouri v. Illinois, a suit filed in 1906 after a typhus epidemic broke out in Saint Louis.

In short, the popular version of our civic epic fogs the detail that when we diverted Lake Michigan through construction of the Sanitary and Ship Canal and later the North Shore Channel (1910) and Cal-Sag Channel (1922)–which collectively were named one of the top ten public-works projects of the 20th century by the American Public Works Association–the rest of the Great Lakes basin despised us for it. There’s not a word in the new compact that endorses the diversion, and Chicago wouldn’t stand a snowball’s chance in hell of pulling off the same kind of stunt today.

Waukesha is a small Wisconsin city about 80 miles north of Chicago and 15 miles west of the Milwaukee lakefront. It’s the focus of the August New York Times article in which Todd Ambs was quoted. Because it stands just beyond the Great Lakes watershed it’s been denied direct access to water from Lake Michigan, drawing its water instead from an aquifer; after decades of depletion, Waukesha is now drawing water from so deep that it’s contaminated with radium. Some geologists believe the aquifer is fed belowground by Lake Michigan, which is why the general manager of Waukesha’s water utility told the Times he simply wants to shift from “a vertical straw to a horizontal straw.” All we need, he said, is permission to divert 20 million gallons of lake water a day. He’s been told no. Chicago gets to permanently remove about 2.1 billion gallons a day. Too bad we can’t just flush some of it to Waukesha.

This has to be one of the most flagrant double standards on the face of the earth. On December 12 the governors of Wisconsin and Ohio (cochairs of the Council of Great Lakes Governors) and Mayor Daley (chair of the Great Lakes and Saint Lawrence Cities Initiative) signed–in Chicago, no less–a letter to President Bush asking for another $300 million in federal funds for programs “to better protect and restore Great Lakes.” Virtue drips from this ambition. But consider the irony. No step to restore the Great Lakes approaches the one that’s not on the table: returning our beloved backward-flowing river to its true path.

It’s telling that during the winter water at the bottom of the Chicago River continues to seek the lake, though the surface water flows in the opposite direction. The river remembers what it was–it yearns to be again an eastward-slogging slough. I suggest we respect the river’s wishes. Let it once more replenish the lake. True, the Sanitary and Ship Canal would run dry, but it would make a fine bicycle path.

There are reasons not to rush into this. Dan Injerd, chief of the Lake Michigan management section of Illinois’ Department of Natural Resources, says it’s been calculated that a century of diversion through Chicago has lowered Lake Michigan by a total of 2.1 inches. So we’re not exactly draining it dry. What’s more, while Chicago diverts water out of Lake Michigan at 3,200 cubic feet a second, Canada, to support hydroelectric plants, redirects water that would otherwise drain into James Bay into Lake Superior at 5,000 cubic feet a second. When everything’s added up the Great Lakes basin gains more than it loses from human meddling.

Then there’s the fact that for more than a century commerce has developed around the man-made reality that water flows away from Chicago. The Sanitary and Ship Canal is a busy federal waterway lined by communities such as Lockport that would not take kindly to seeing the canal disappear.

As for the argument one hears from time to time–that it’s simply wrong for Chicago to flush its wastewater downstream to Saint Louis and New Orleans–there’s this rejoinder: waste treatment has progressed by leaps and bounds. Saint Louis hasn’t had a typhus scare in decades.

In Injerd’s view, the financial cost of undoing and redoing the region’s hydrology would be staggering and the ecological issues profound. The subject does come up, he allows, primarily in the context of the invasive-species problem. In 1990 a nuisance fish called the round goby, native to the Black and Caspian seas, turned up in the Great Lakes. By 1994 it had spread to the Calumet River, which meant there was no way to keep it out of the Mississippi River watershed. At the moment the big concern is the far more destructive Asian carp, which has worked its way up the Illinois River from the Mississippi to within 50 miles of Lake Michigan. To keep it out of the Great Lakes, Illinois has joined forces with five national and international agencies to build a $9 million electronic barrier across the canal at Romeoville to replace the current temporary barrier.

Alien species notwithstanding, the Chicago diversion is a political and legal issue. Seven other states and two provinces just dealt with it in the Great Lakes-Saint Lawrence River Basin Water Resources Compact by holding their noses and going along with a done deal. “It was grandfathered in,” says hydrologist Daniel Feinstein of the University of Wisconsin. “It was seen as a very specific, adjudicated, confined, isolated diversion. It’s not seen as a precedent–Waukesha is seen as a precedent. It was a one-shot thing.”

There’s hope in Waukesha. If it finds a way to return to the basin as much water as it removes, it might yet be allowed to tap Lake Michigan. If Chicago ever asks the Supreme Court for permission to divert more than 3,200 cubic feet of water per second, seven states and two provinces will line up against it. Arid America might one day view even its present allotment as a provocation worthy of war.

Injerd thinks the economics of piping lake water great distances will never justify a raid by Phoenix. Arizona officials–if not Cassandras like Alan Christopher–claim to agree with him. Doug Dunham, who manages that state’s Assured Water Supply Program, says any crisis is 60 or more years away, and at that point desalination plants will make more economic sense than a pipeline through the Rockies. But Las Vegas, where there are already laws against growing grass, is in more desperate straits. And between Vegas and Chicago lies the vast, drought-plagued Great Plains, rapidly draining the Oglala aquifer. The truth is, no one on earth has enough water. No one but us.

Wisconsin’s Todd Ambs speaks of our water with the ferocity of someone preparing for a siege. “I’m sure that in the future folks will begin to look longingly at what I like to refer to as the water belt of the country,” he told me. “And if we do this right and we get this agreement in place and we are managing our water effectively, then we are in a position as an area to say, ‘Hey, we put our system in place in 2005 to do a good job of managing our water resources. What right do you have to come in now and ask for water because you haven’t done a good job of managing your water resources?'”

The answer to that, I reminded him, will be, “We never had the water resources to begin with.”

He said he’d tell them, “You can move to Chicago or Milwaukee or Detroit or any one of many lovely communities that are up here in the midwest and actually have the benefit of having water for their populations.”

Ambs went on, “We have to grapple with the fact we need enough energy resources to sustain a population that’s snowed in six months of the year. Phoenix has to manage its resources in a region where they have a very, very limited water supply. Frankly, there’s going to be a point in some of those places where they say, ‘You know what? We can’t handle any more people in this area.'”

That would be like the United States telling itself, “Screw Saudi Arabia. We’ll just stop driving cars.” The Great Lakes basin has what the whole world wants. It should expect the world to come after it. United we must stand.

The rereversal of the Chicago River would be an extraordinary undertaking, undoubtedly one of the top public-works projects of the 21st century. But it’s the thing to do. “Why not bring integrity back to the levels and flows in the basin?” muses Jim Olson, attorney for Michigan Citizens for Water Conservation, the grassroots organization that took on Nestle over Ice Mountain bottled water. The Chicago diversion, he says, is “a historical artifact. It’s directly contrary to the intent of the [compact] agreement.”

The big question, says Olson, is who pays? He thinks that since Chicago has rights over Great Lakes water no other state or city has, in giving them up it would be acting more clearly in the basin’s interests than in its own. So it should be rewarded. “The rest of the basin would have to negotiate with Chicago to help pay for this,” he says.

That’s the beautiful thing. Seven states and two provinces will admire us so much for doing what’s right that with a little smooth talking they could wind up footing most of the bill.

Art accompanying story in printed newspaper (not available in this archive): illustration/Paul Dolan.