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Know the West

How low will it go?

Colorado may face a dry and difficult future of fighting for water


Eric Kuhn is not the person you'd expect to deliver ominous revelations about Colorado's future.

Kuhn runs the Colorado River Water Conservation District, which represents 15 counties on the state's Western Slope. Compared to some of Colorado's other water agencies, the River District leads a relatively low-profile existence on one floor of a small office building in the mountain town of Glenwood Springs. The district has 23 employees, a dog-friendly office policy and a vehicle fleet composed mainly of Subarus, all of which gives the enterprise the folksy charm of an REI catalog. 

At the age of 59, Kuhn is resistant to many of the most rudimentary conventions of the water business -- things like bolo ties and golf -- and he is not particularly partial to the back-slapping bonhomie in which even the staunchest water adversaries often engage. He favors jeans and Nikes, and sometimes leaves the office to walk a footpath along the river and turn over problems in his mind.

Kuhn has a warm personality and a fierce, focused intelligence. He devotes a great deal of energy to understanding things like the relative performance characteristics of various types of weather radar, and he has been known to wander off in the middle of a conversation when an important breakthrough materializes in his head. "He's one of these scary-brilliant people," says his wife, Sue. "It's just kind of how he's wired."

He also has something of the manner of a well-read naval officer -- which, it turns out, he once was. He spent six years aboard submarines, spying on the Soviets' nuclear weapons program. It's tempting to think that Kuhn's way of thinking about the Colorado River was shaped by those long deployments in the murky depths, when his submarine's survival depended on the intelligent interpretation of what little data could be gathered.

Kuhn has lately become obsessed with one of the bigger riddles hanging over Colorado's future, and his quest for answers has challenged some of the fundamental tenets of the state's water orthodoxy. 

"I've always been concerned that our reliable water supply is a lot less than what we've been suggesting," he says. "I think there's a lot less available than we thought there was."

More than 3 million people in Colorado -- roughly two-thirds of the state's population -- rely on water from the Colorado River. The river sustains alfalfa, apples and pears, Olathe sweet corn, and ski and ranch towns across the Western Slope. Yet its water may be even more important to the Front Range -- Denver and its cluster of urban and suburban satellites that lie hard against the eastern foothills of the Rockies.

More than a dozen tunnels channel water underneath the Continental Divide to roughly 2.5 million people on the Front Range. Moreover, the state is expected to grow by 2.9 million people over the next 25 years, and the Colorado River has long been seen as the only real source of water for the future.

So it's not surprising that water managers have, for years, privately asked: How much more of the Colorado River can the state use?

Publicly, the state's water managers tend to stick to a time-worn mantra: Under the terms of the interstate treaties that govern the river, Colorado still has as much as 1.5 million acre-feet left to develop. That's enough water for about 12 million new residents, more than four times the state's official population projection for the next quarter of a century.

But there has always been an unspoken acknowledgment of a much grimmer possibility. Six other states also rely on the Colorado River. And between the peculiarities of the so-called Law of the River and mistaken assumptions about the river's long-term performance, Colorado may have to content itself with little more than "the right to leftovers," as two observers once put it. In a severe drought, in fact, cities and farms within the state could be pitted against each other in a fight for water.

That always seemed like an abstract possibility, until just such a drought wrapped its hands around the river in 1999, and kept them there right up to the present day. And so Kuhn decided it was time he figured out just how much water was left for Colorado -- and, by extension, how long the state could continue to grow.

Until recently, "the thought in Colorado was that it would take another hundred years," Kuhn says. "But the water supply we thought we had isn't there."

Kuhn was born on July 4, 1950, in Edmonton, Alberta, where his father was working as a petroleum geologist for Texaco. When Kuhn was 8, his family moved to Flagstaff, Ariz.

Kuhn's grandfather, who lived in Prescott, would often fly up in his Piper Cub -- a tail-dragger without a radio -- and take Kuhn flying over the Grand Canyon and the Indian country of northern Arizona. "In those days," Kuhn says, "you didn't need a pilot's license. All you needed was an airfield."

Kuhn's dad flew, too -- he had been a Marine pilot in World War II -- and for a while, Kuhn seemed set to carry on the family's aviating tradition. He went to the University of New Mexico on a naval ROTC scholarship, where he got his pilot's license. But his vision wasn't good enough to meet the Navy's requirements, and so Kuhn, who graduated in 1971 with an engineering degree, went into the submarine service instead.

In late 1972, Kuhn found himself aboard a submarine called the Halibut as it steamed under the Golden Gate Bridge and then dove deep beneath the Pacific -- headed for the Kamchatka Peninsula on the easternmost edge of Siberia. Kuhn found himself wondering, "What have I gotten into?"

The Halibut carried a contingent of operatives from the National Security Agency, and it slowly crept into the Sea of Okhotsk, where the Soviets conducted many of their ballistic missile tests. There, in 28.6-degree water 500 feet below the surface, the Halibut deployed a dive team. Breathing helium to counteract the intense pressure, kept alive by hot water continuously pumped through their dive suits and working in pitch black, the divers located a Soviet underwater communications cable. Then they wiretapped it.

That mission and several others would yield crucial information about the Soviets' ballistic missile-testing program, helping the Navy maintain its edge in a spiraling arms race between the Soviets' nuclear-armed "boomers" and the American attack subs designed to destroy them before they could vaporize the U.S. But the voyages were so secret that it would be 20 years before Kuhn finally told his family exactly what he had done aboard the Halibut.

After his discharge from the Navy in 1978, Kuhn got a graduate degree at Pepperdine and went to work for the engineering giant Bechtel, starting up the Palo Verde nuclear power plant near Phoenix and the San Onofre nuclear plant outside San Diego. But he didn't stay long: Three Mile Island melted down in 1979, and "the handwriting was on the wall," he says. "No one was building any new power plants."

An ad in the Wall Street Journal, for an engineering position at the River District, led him to Colorado.

Kuhn arrived at the River District in 1981 with no particular expertise in water but filled with his trademark curiosity. "It looked like an adventure to me," he recalls.

From the start, Kuhn immersed himself in the river's convoluted history, and as he worked his way up the ladder (he became general manager in 1996), his curiosity intensified. Then that curiosity became a professional imperative.

In 1999, the drought set in. In 2002, the river's flow was just 25 percent of average. And by 2004, Lake Powell and Lake Mead -- the main backup supply for water in the Colorado River -- were half-empty.

Sometime late in 2006, Kuhn embarked on an exhaustive review of the literature to understand how much water the river could reliably deliver. He estimates that he spent almost 25 hours a week over the next seven months, reading some 10,000 to 15,000 pages.

Kuhn pored over reports from the river's earliest explorers, congressional testimony and comprehensive plans for development, pleadings from court cases, and an avalanche of scientific papers about El Nino, tree-ring chronologies, climate change and obscure phenomena like the Atlantic Multi-Decadal Oscillation and shifts in the onset of spring runoff. Along the way, he became one of a handful of people who have developed a true connoisseur's delight in the exegetical nuances of the 1922 Colorado River Compact and its reams of related documents and scholarly analysis.

He gradually synthesized what he had learned into a 111-page report. Much of it he wrote out longhand, making reference along the way to Deuteronomy, the modified Blaney-Criddle methodology for determining the consumptive water use of pasture grasses, and The Incredible Shrinking Man. "When he was writing, it was constant. He would come home and write till he went to bed," says Sue Kuhn. "He was really excited about the whole thing. He was thrilled."

Kuhn's office bookshelf holds several ink-stained, broken-spined old government publications, and, his report makes clear, they stand as a useful metaphor for the broader history of the river. They are essentially a series of warnings that came at the wrong time.

In 1924, just two years after the Colorado Compact was signed, a government hydrologist calculated that the actual flow of the river was 10 percent less than the Compact negotiators had assumed. In 1965, a water engineer named Royce Tipton estimated that the river's reliable flow was really about 14 percent less. "That was pretty shocking at the time," Kuhn says. It only got worse: Subsequent reports found that long-term flows were fully 22 percent less. "But then we just kind of put those reports on the table and went back to saying there's a lot of water.

"About the time the Tipton report was done, things turned wet. And they stayed wet through the late '90s," he says. "That wet period was the beginning of the Rocky Mountain boom days. That's when our growth exploded in the West."

The wet cycle meant there was more than enough water to accommodate the growth spurt, at least for the next 35 years. It also caused a weird psychological drift for water managers. Although severe droughts had left their mark hundreds of years back in the paleologic record, the 20th century was abnormally wet. Consequently, what we think of as normal is, in fact, unnaturally wet, compared to the much longer lifetime of the Colorado River.

Throw in climate change, which will almost certainly result in a decrease in average flows for the Colorado River (though to what extent is still hotly contested), and things really start looking grim. The desert Southwest is facing the slow decay of the water supply upon which the region has been built.

"An 80 percent year is not that bad. But if we had 20 years of 80 percent runoff on the Colorado River, we'd drain Lake Mead and Lake Powell," Kuhn says. "We're so close between supply and demand that a long period of 80- or 85-percent years will bankrupt the system."

Kuhn's quest to understand the river put him at the front of a sometimes lonely fight to challenge the conventional wisdom in Colorado. Some saw his argument as a self-interested effort to keep the Front Range from stealing the Western Slope's water, by arguing that there wasn't any water left to take. But during the summer of 2007, Kuhn's conclusions were validated in a surprising way.

Several Western Slope communities sued Denver to prevent the city from securing new rights to Colorado River water. They argued, basically, that there simply wasn't enough water in the river.

Glenn Porzak was the lawyer who argued against Denver in the case. And, as it happened, he had seen a copy of Kuhn's report. "(Kuhn) sent it out to a number of people, saying, ‘Give me your comments,' " says Porzak. "I read this thing and said, ‘I'll give you my comment: I want you as a witness in this case.' "

So Kuhn took the stand on June 13, and carefully noted that "there's no single answer to how much water Colorado has left to develop. The answer is a function of how much risk the water users in Colorado are willing to take." But, he testified, the amount of water that the state can reliably count on is no more than 150,000 acre-feet -- considerably less than half of what would be needed for the 2.9 million people projected to arrive over the next quarter century.

Denver Water's attorney, Casey Funk, opened his cross-examination by remarking, "Boy, that's a pretty pessimistic view of the future, Mr. Kuhn. Does the state of Colorado share that same opinion?"


As a matter of fact, the state of Colorado did share that opinion, although that wouldn't become clear until 13 days later. On June 26, Denver Water called its own witness: a man named Randy Seaholm, who is the state's chief of water supply protection.

Funk walked Seaholm through the process of calculating how much water remained available for development. Based on what might be termed a constructionist reading of the Colorado River Compact, that number works out to roughly 1.5 million acre-feet. Still, most water managers recognize that the numbers on which the Compact is based are at least somewhat higher than the river itself can reliably deliver. So Funk took Seaholm through a second set of calculations, this one based on a recent "hydrologic determination" by the federal government.

"And that would leave, then, an amount of around 600,000 acre-feet left to develop under the Compact, based upon that determination?" Funk asked. "Correct," answered Seaholm.

Still, that wasn't bad. It's enough for about 4.8 million people.

Just before the hearing, however, Glenn Porzak secured a copy of an internal document, prepared by Seaholm only eight days earlier. The document showed that, at the time of the trial, Colorado actually had only 474,000 acre-feet of water left to develop. More importantly, it showed that once existing and approved projects were built and operating at full capacity -- which, according to the document, will be next year -- only 159,000 acre-feet of water will be left.

The number almost exactly matched Eric Kuhn's, and it is only about one-tenth of what the state had officially been saying was available.

"Denver led him through the state mantra: ‘OK, on paper, we've got this amount, and we're never gonna admit anything to the contrary,' " Porzak says. "And then it turns out there's this internal document that's just unbelievably close to Eric Kuhn's number.

"I've been practicing 35 years," he added, "and I've had some good moments. But it was the closest thing I've ever had to a Perry Mason moment."

It was never a great secret that the limits of Colorado's water allocation have been gradually closing in. But Kuhn's emperor-has-no-clothes pronouncements have nonetheless come at considerable cost to the state's self-respect.

His findings mean, first, that reliable water supplies for each additional bit of growth are becoming increasingly uncertain. Second, they call into question the viability of at least two proposals to divert water to the Front Range: One that would draw as much as 300,000 acre-feet of water from the Yampa River, a tributary of the Colorado; and another, floated by an entrepreneur named Aaron Million, that would pump roughly 250,000 acre-feet from the Green River, itself a Colorado tributary. Kuhn's findings also suggest that there's little water left for the predicted explosion of oil shale development in western Colorado, which could require up to 400,000 acre-feet per year. It's anybody's guess when, or whether, oil shale will go forward, but large energy companies like Shell have already filed claims for hundreds of thousands of acre-feet of water.

All of that raises the prospect that growth -- or at least growth with a dependable water supply -- may soon be finished in Colorado. And that's not a message that has been well received.

For roughly the past decade, Scott Balcomb was Colorado's lead representative in negotiations with the six other states that use the river. His task was, basically, to protect the state's water allocation from its rivals. "If we voluntarily decide that we're limited to x acre-feet in our development, and we want to be very safe, we're almost inevitably going to leave water on the table that we could develop," he says. "And I don't like that very much."

In fact, the issue is so sensitive that when Randy Seaholm testified at the Denver water trial in 2007, a state assistant attorney general accompanied him to intervene if he said anything that might compromise Colorado's negotiating position against the other states. Why the attorney general's office didn't move to have Seaholm's water-availability estimates put under seal is not clear. Balcomb, for his part, says that if the state publicly acknowledges that it has only 150,000 acre-feet left -- which it essentially did in the trial -- that number will boomerang back against Colorado in some future fight between the states over the river's last remaining water.

The Colorado River Compact is essentially a contract between the seven states, and its terms were consciously crafted to enable a kind of mutual coexistence. If legal rights to the river had simply been apportioned following Western custom -- the hallowed doctrine of "prior appropriation," which grants rights to whoever first uses the water -- early-blooming California could have laid claim to a large portion of the river's water in 1922.

As part of the Compact bargain, then, Colorado and the other Upper Basin states -- Utah, Wyoming and New Mexico -- managed to reserve 7.5 million acre-feet for themselves. That gave them certainty that their share of the river wouldn't be gobbled up by California before they needed it. But the price of that certainty was a deal that gives the Lower Basin a significant advantage when times get tight.

That proviso says -- stick with this for a moment -- that the Upper Basin states "will not cause the flow of the river at Lee Ferry" -- the dividing line between the two basins -- "to be depleted below an aggregate of 75,000,000 acre-feet for any period of ten consecutive years." Put differently, that means the Upper Basin will do nothing to prevent the flow of 7.5 million acre-feet downstream to the Lower Basin each year. (As Compact aficionados will rush to point out, the precise terms of the clause dictate that the amount be calculated as a running average of 75 million acre-feet over 10 years -- or "75 over 10," in Compact-ese.)

The problem, of course, is that the Compact promises more than the river can deliver. The Lower Basin gets 7.5 million acre-feet of water from the river's mainstem; the Upper Basin gets its 7.5 million acre-feet; and Mexico gets 1.5 million acre-feet, for a total of 16.5 million acre-feet. But over the long run, the river's mainstem can probably only reliably deliver about 13.5 million acre-feet. In 1986, that mismatch caused John Carlson, then special counsel to the River District, to write, "Unfortunately, the mathematics of the law of the river simply have not worked: The sum of the parts is greater than the whole."

Still, that hasn't been a problem -- yet. Lake Mead and Lake Powell provide the backup capacity that ensures enough water for every state. "But what makes that sustainable is only these rare -- and maybe becoming rarer -- big, wet (El Nino) events that fill Lake Powell," says Kuhn. In the middle of an extended drought, a powerful El Nino could temporarily boost reservoir levels. But if the drought continues, levels will continue dropping again. "Then," he says, "you're waiting to see if you have another wet year."

After nearly a decade of drought, the reservoirs are half empty. If they continue to drop, that will touch off a fight over what little water is in the river, like creditors battling over the carcass of a bankrupted company. And, owing to the 75-over-10 provision, California and the other Lower Basin states get first dibs on their 7.5 million acre-feet. If conditions get bad enough, the Lower Basin states could make a legal "call" on the river and demand that the Upper Basin not take any of its Compact water until the 10-year average once more rose above 75 million acre-feet.

Legal scholars David Getches and Charles Meyers described the predicament poignantly 23 years ago: "How to build a future on the right to leftovers?"

While there may not be much water left for new projects in Colorado, there is also a high risk that existing users -- anyone whose rights post-date the 1922 signing of the Compact -- will be "called out" and cut off to meet the Lower Basin's demands. That could set off a civil war within the state.

To comply with a call, Colorado and the other Upper Basin states would have to shut down their own water users to satisfy their share of the "delivery obligation." Currently, that would be done according to the rules of prior appropriation: More recent, or "junior," users would be shut down first; then the state government would work its way backwards, shutting down increasingly senior rights until the delivery obligation was met.

But some of the most junior -- which is to say, the most at-risk -- water users are the water agencies that pipe Colorado River water under the Continental Divide to supply the Front Range. Chips Barry is the manager of Denver Water, the state's largest urban water agency, which supplies about 1.3 million people. In a worst-case scenario, "every right on the Colorado River, post-1922, gets called out," he says. "Now if that happens, that's a disaster for the state of Colorado, and for Denver Water."

Denver would implement strict water conservation and efficiency measures, but beyond that its only option would be to buy water rights around the state that were in use prior to 1922. And every acre-foot that Denver tried to grab would be one that someone else in Colorado already uses.

That would pit the state's cities against its farmers, and put the problem straight back in Kuhn's lap: Most of those pre-1922 rights are held by farms in the River District's territory. And so Kuhn is already thinking about how to prevent the Front Range from buying up farms on the Western Slope, taking their water, and leaving them dry.

The plan -- which he's been developing with Denver Water and several other water agencies -- is to create a water "bank" that bundles together pre-1922 water rights on the Western Slope. Those could then be used to cover deficits on the Front Range in a call. The bank would sign agreements with farmers in advance, and pay them to irrigate, say, only half their ground in a bad year. The water that would have been used on the other half would then go to cover critical municipal uses. When the drought ended, the farmers would get back full use of their water.

Kuhn insists that such a deal can only come if the Front Range cities put aggressive water-austerity measures in place and use Western Slope water for only the most critical uses. But he acknowledges that it would be impossible for the Western Slope to simply stonewall the Front Range if its cities are clamoring for water in an emergency. "You can ask them to brown their lawns, but their fire hydrants still have to be charged," he says. "You can't ask them to go without (drinking) water."

Despite occasional rancor, the questions that drive Eric Kuhn are increasingly ones that Colorado's water managers are willing to discuss in their own polite company. And there is growing hope that real answers may burn through the miasmal haze that has, till now, shrouded the crucial question of how much more water Colorado can develop.

In 2007, largely thanks to Kuhn's urging, the Colorado Legislature passed a bill funding a far-more-detailed analysis of water availability than the state has yet attempted. In addition, the Colorado Water Conservation Board is working to assess exactly how the state's water users might be shut off to meet a Compact call.

That process is sure to bring many uncomfortable questions into the open. "I have no illusions that we're going to get through this without a lot of bloodletting," says Randy Seaholm. Still, he said last December, the prospect of a call is not as dire as Kuhn would have it: "Eric is right when he says every additional drop of water you develop increases the risk that a senior water right may be curtailed in the future. But that's been the case since we started developing water."

Yet the margin of error is thinner today than ever before. Kuhn frequently invokes a cautionary example of the human cost of a call.

Along the South Platte River in northeastern Colorado, farmers for nearly 30 years had made massive investments to pump groundwater for their farms. In reality, the water they were pumping was being sucked out of the river -- and it was water that had other, more senior farmers' names on it.

The pumping was technically illegal. But a series of jerry-rigged compromises were made. And for decades, things were wet enough that there was enough water to go around.

Then there wasn't.

In 2002 -- the same year that rang alarm bells for the Colorado River's water managers -- water supplies on the South Platte plummeted, and a judge ordered that more than 2,000 wells be shut down so that the senior river-water users could get their water. Many farms have never recovered.

"It's just a nightmare," says Tom Cech, the head of the Central Colorado Water Conservancy District. "It's just a terrible, terrible tragedy."

Many farmers have had to move out of the area. Those who can still pump can only run every other pump, and even then at rates far below what they did in the past. Still other farmers have been reduced to dryland farming. "They're trying to survive on dryland income," Cech says, "which is kind of like going from a salaried position to minimum wage."

That's the kind of disaster Kuhn says the state can't afford to repeat. "In the South Platte, we intentionally chose political expedience over good science," he says. "We knew better, but people chose to make the wrong decision because it was the political path of least resistance."

Kuhn has had to contend with the old Biblical maxim that prophets are rejected in their home towns. He understands that he has cracked open an ugly Pandora's box. But he also has spoken out only after considerable soul searching about the consequences of not doing so.

"Look, I don't know that I'm right," he said last December, as he gunned one of the River District's Subarus over Vail Pass en route to a water meeting. "But I don't think I should be criticized for openly stating what everybody else understands, but is unwilling to talk about."

This article was made possible with support from the Kenney Brothers Foundation.