In 2002, water levels at Cheesman Reservoir dropped 65 percent due to drought. Scientists warn that such droughts may become more frequent. Photo: Marc Piscotty
Early Western settlers believed that rain followed the plow, but today we realize that when it comes to natural resources, supply doesn’t always increase with demand.
Scientists have discovered that even with recent droughts the last century has been one of the wettest on record. But it won’t stay that way, and scientists and urban planners alike are wondering if there will be enough water to supply current and future generations.
In Colorado, the population is expected to nearly double in the next quarter century, but natural limitations on the state’s water resources aren’t changing for the better. Will proposed agricultural and municipal efficiencies, new water storage facilities and more cooperative efforts among diverse water users be enough to supply everyone with water?
Members of the Water Futures Panel assembled by DU last year think so. The panel issued a report outlining measures to improve the state’s water outlook.
Still, Colorado’s looming water problem is one of those complex issues that has no simple fix. That’s one thing nearly everyone can agree on. But listening to water managers and scientists discuss challenges, solutions and timetables, one thing becomes clear: We’d better dive on in.
A question of time
The doomsayers are largely scientists who take the long view. They aren’t looking at drought and rainfall in the last five years; they’re looking at centuries of data. What they’ve discovered is that current and future expectations are based on anomalies.
Tree rings show that when engineers were planning the Hoover Dam in the 1920s, it was one of the wettest quarter centuries of the last millennium. When the Colorado River’s future flows were apportioned between Upper and Lower Basin states, the hydrologic data at the time offered more water than the river would have to give in most years.
In September 2007, the 24-member Water Futures Panel assembled by DU issued a report recommending strategies for water sustainability:
1. Embrace fairness, trust, respect and openness in water supply planning
2. Encourage water conservation
3. Encourage partnerships between urban and agricultural water users
4. Eradicate non-native phreatophytes (high water consuming plants, such as tamarisk and Russian Olive)
5. Streamline the Water Court
6. Encourage statewide perspective on water storage and infrastructure projects
7. Facilitate cooperation between river basins
8. Plan for potential climate change and drought
9. Maintain healthy rivers and in-stream flows
Learn more about DU’s Strategic Issues Program and read the full water report at www.du.edu/issues.
Scientists are discovering that climate change is happening swiftly, and like rafters running Class V rapids, adaptation is critical to survival. If water management planners aren’t using worst-case scenarios or plugging multitudinous factors into their models, scientists say they aren’t adequately preparing for the future.
Water managers are pragmatic stewards who, while taking in all the information, tend to build upon past successes. If users can conserve water in drought years, they’ll be able to do it again. If efficiencies, cooperative agreements and good planning have worked, more of the same will continue to work. Most say there’s always been drought; there’s always been climate change. They are working toward meeting future demand but not expecting the sky to fall.
Somewhere between the halcyon and bleak projections lie the facts.
A semi-arid state, Colorado receives, on average, 17 inches of precipitation annually. It falls in the form of rain and snow, primarily on the Western Slope; some is transported to the more populous Front Range. In an average year the state generates some 16 million acre-feet of renewable water. (An acre-foot of water is enough to flood the infield at Coors Field to a depth of 5.4 feet).
So far 2008 looks like a good year for water. In April the Office of the State Engineer reported that most of the state’s major river basins had above-normal water supplies.
Besides annual precipitation, Colorado depends on water set aside in its 2,000 reservoirs. In the drought year of 2002, Colorado rivers delivered about a quarter of their usual flow, and water stored in reservoirs was tapped to make up the difference.
Aquifers deep below the earth’s surface also provide water for many Coloradans, but over the last hundred years, wells tapping into the Denver Basin aquifers have become less reliable, with some wells drying up. According to the U.S. Geological Survey, withdrawal rates have greatly exceeded recharges in the Denver Basin aquifers during the last century.
In Colorado, water is used for drinking, bathing and watering lawns (where that’s legal). It irrigates cantaloupe growing in Rocky Ford. It keeps wild trout in the Cache la Poudre for anglers, offers rafters the rush of running rapids and provides beautiful views in Rocky Mountain National Park at places like Thunder Lake. And, of course, snow provides recreation for upward of 12 million skiers annually. It breaks down like so: More than 86 percent of the state’s water is used for agriculture, 7 percent goes to home use, industrial and commercial uses account for 2 percent, recreation and fisheries use about 3 percent, augmentation and recharge of groundwater aquifers use 1 percent each.
But not all of the water in Colorado is Colorado’s to keep. The state delivers two-thirds of its water to downstream users as far south as Mexico as required by a variety of complex agreements.
Here at home, water managers will be increasingly challenged to provide enough water for everyone as the state’s population grows from more than 4.8 million today to nearly eight million in 2035, as projected by the Colorado Division of Local Government’s demography office.
The problem is threefold: Current water compacts were established when water was plentiful, and some agreements on apportioning the state’s water are law; climate change may further decrease available water; and plans to handle the increasing demand for water may be inadequate to address the rapidly changing environment.
That last point is becoming more apparent as scientific study after study finds conditions are worsening quicker than expected. An international research team led by Tim Barnett and David Pierce of the Scripps Institution of Oceanography reports that the West is heating up and snow pack has decreased over the last five decades. They found a link between greenhouse gases caused by human actions and the West’s water supply. Natural climate variability doesn’t explain it.
“It foretells of water shortages, lack of storage capacity to meet seasonally changing river flow, transfers of water from agriculture to urban uses and other critical impacts,” they wrote in a Feb. 1 ScienceXpress article. David Pierce, one of the report’s authors, says the Colorado Rockies will fare better than the Sierra Nevadas because the Rockies are colder and the Colorado River has a greater reservoir capacity, leaving it less susceptible to snow melt and reservoir flooding. Still, Pierce says, warmer temperatures carry a double punch of declining snow pack and increased evaporation. An added wallop is the forecast of a 10-30 percent decrease in runoff in the region by mid-century.
Barnett says it’s a mistake for planners to ignore future climate change models. “Our work shows this is no longer a valid approach to water management in the West,” he says.
A Feb. 1 Science article about climate change calls for changing the way water is managed from the assumption that climate will remain relatively stable to using sophisticated climate modeling that would factor in historical hydrologic measures “with projections of multiple climate models, driven by multiple climate-forcing scenarios.”
Whether or not climate change turns out to be as dire as projected, more people will necessitate greater demand.
“I believe that water is our most precious natural resource. It is limited spatially, temporally, quantitatively and qualitatively. As a result, conflict is bound to exist as demand for water increases for any use,” says Dick Wolfe, state engineer at the Colorado Division of Water Resources.
Other states may deal with water conflicts differently, but in Colorado the rules are set — pretty much in stone. In Colorado, people with senior priorities get to use the water first, and at times there may not be any left for those with junior priorities. Like many Western states, Colorado uses “prior appropriation” as the determining factor. It’s dubbed “first in time, first in right,” and as DU law Professor and Assistant Dean Daniel Vigil explains, water rights are chronological, with those holding oldest or senior rights having priority over newer or junior rights. A person must put water to beneficial use to establish a right to it, and that right is protected by Colorado’s Constitution.
Colorado is the only state that uses a water court to administer water law and settle disputes. Although the court is often criticized for being slow and expensive, “It works fairly well,” Vigil says. “The question is, Where do you want to rest the power? The administrative system has power in other states; then they go to court. Here we rest the power with the court rather than the administrator.” DU’s water panel recommended streamlining the court, and complaints of logjams prompted Gov. Bill Ritter to appoint a Colorado Supreme Court task force to review the system.
If the system is fair when there’s enough water for everyone, what happens when water is scarce? In times of drought, domestic water use can, in some instances, take priority over agricultural and manufacturing uses.
A Colorado Division of Water Resources Surface Water Supply Index report notes that since the 1950s, water supplies have been transferred from agricultural to urban use as population demands increased. Such transfers could threaten a healthy agricultural economy and the rural communities that depend on them — an issue that troubles DU panelists, who encourage agricultural and urban interests to craft mutually beneficial water transfer agreements.
“Colorado can have a sustainable water future where no economic, agricultural, geographic, or environmental sector has to lose at the expense of another’s interests,” the panel wrote in its report.
Not everyone agrees. Farming and ranching advocates, for example, say transfers aren’t a feasible solution for meeting Colorado’s future water needs. The Colorado Agricultural Water Alliance issued a report this year cautioning against the perception that agricultural conservation would provide enough water to meet growing demands. It notes that about a third of Colorado’s irrigated acres have already been converted to more efficient sprinkler or drip systems, and there’s not a lot of efficiency left to be gained.
Come together
Still, a number of groups are working together to improve the state’s water supply issues, and they’re examining a wide variety of ways to maximize Colorado’s water. Some of the players include the Colorado Water Conservation Board, the state agency responsible for addressing Colorado’s water future; the Colorado Ground Water Commission; the Colorado Division of Water Resources; the Colorado Department of Public Health and Environment; and the Interbasin Compact Committee. There are local and regional agencies, too, including 51 water conservancy districts statewide.
Citizens groups and associations also are involved. In response to drought conditions in 2000, 58 of the state’s 64 counties drafted a declaration of water principles regarding future water problems. In 2003, a series of meetings led by then-Secretary of the Interior Gale Norton (BA ’75, JD ’78) and attended by 3,000 individuals resulted in Water 2025, a plan for preventing crisis and conflict in the West. The Interbasin Compact Committee met this spring to discuss a 50-year water plan. And last year, the University of Denver waded in with its Water Futures Panel.
There are more than just thoughtful suggestions afloat; changes are already afoot. In 2007, Colorado Gov. Bill Ritter issued executive orders aimed at reducing water consumption in state facilities by 10 percent. Among other actions, his office awarded $1.2 million in grants to increase water storage, and he signed a House bill to allow water judges to consider environmental impacts and water quality in determining large, permanent water transfers.
And, of course, the federal government also has some say in how the state handles its water.
With all of these minds devoted to Colorado’s water future, is there cause for worry? The answer depends entirely on whom you ask.
On average, Denver Water supplies about 285,000 acre-feet of water annually to metro area users, according to manager Chips Barry. One acre-foot can supply a family of four for nearly 24 months, Barry says. He projects a demand increase of about 23 percent by 2030 and says plans for conservation, recycling and increased storage will help meet demand.
Wolfe says that although the legislature can play an active role in getting stakeholders to achieve a sustainable supply, it isn’t all up to the government. “The citizens of Colorado must decide how they want the state to look like in 50 years, 100 years and beyond,” he says, noting focus groups and roundtables that are looking at current and future basin water demands and proposed projects to meet them.
In Colorado, water providers have done a good job of planning, says Jennifer Gimbel, Colorado Water Conservation Board director. “If successful, their plans will help meet 80 percent of our future need. Addressing the remaining 20 percent will require creative solutions and greater coordination and collaboration between users and different areas of the state.” Examples of solutions at hand, Gimbel says, include: efficient water use through strong conservation and water reuse efforts; transfers from existing to new uses, such as agricultural transfers; using and enlarging existing water storage facilities, along with creating new ones; and conjunctive use between surface and ground water.
Naturalist and award-winning author Craig Childs isn’t so optimistic. He has spent much of his life in southwestern deserts where water is never far from mind. He describes this year in Colorado as “rich” with “deep banks full of melted snow.”
He’d like to believe it will continue to be this way but says it’s unlikely. He was born in Arizona, where he says only Phoenix and Tucson legally and physically secured their water supplies, leaving the rest of the state arid. As for Colorado, where Childs lives now, he says, “I can’t help looking ahead, seeing how we will haggle between the Front Range and everywhere else, how this wealth of snow will be squandered by our own opulence, and how Lower Basin states will be sending their armies of bureaucrats to us as reservoirs such as Lake Powell are unable to recover from ever-increasing demand.
“I imagine drier times, more bitter disputes and power plays that decimate communities. It seems as if the way of life we know will have to change under the weight of increasing demand and decreasing supply.”
Wolfe says the state should hope for the best but plan for the worst. He and Gimbel point to efforts under way to increase collaboration and maximize resources as hopeful signs. Water providers, governmental and nongovernmental entities are moving forward with their plans and are increasingly looking for opportunities to work together, Gimbel says. Most of those groups, as well as municipal and industrial water providers, have identified projects and processes to meet their demands through 2030 or 2050, but few have plans in the works that address water supply and demand beyond then. Long-range predictions and plans are problematic, Wolfe says, a reflection of our limited understanding of the complex world we live in. But, he says, the future is made of the same stuff as the present. And the past.
DU’s Dan Vigil reminds, “People rarely have died of thirst in Colorado.”