“The Study is noteworthy for its candid assessment of the possible impacts on water supply brought about by climate change – about a median 9 percent reduction.”
The Colorado River is one of the most heavily relied upon water supply sources in the world, serving 35 million people in seven states and Mexico. The river provides water to large cities, irrigates fields, powers turbines to generate electricity, thrills recreational enthusiasts and serves as a home for birds, fish and wildlife.
Now, a new report by the Bureau of Reclamation (Reclamation) produced in cooperation with the seven Colorado River Basin states and a host of interested parties is casting a cautionary outlook for the water supply picture for the next half-century, with a supply-demand imbalance that will require new degrees of innovation and cooperation by the multitude of people that depend on the river.
The Colorado River Basin Water Supply and Demand Study projects a range of future water supply and demand imbalances. Comparing the median water supply projections to the median water demand projections, the future water supply and demand imbalance is projected to be about 3.2 million acre-feet of water by 2060. The number grows to as much as 7.7 million acre-feet when comparing the water supply projections based on the greatest water demand projections.
“The Study is the most comprehensive Basin-wide analysis ever undertaken by Interior,” said Anne Castle, assistant secretary for water and science for the Department of the Interior (Interior). Interior recognized the Study in October with a “Partners in Conservation” award. “Conducted in collaboration with stakeholders throughout the Basin, including federally recognized tribes, agricultural users, purveyors of municipal and industrial water, power users, and environmental and recreational groups, the Study will serve as the basis for planning for future growth and climate change in the Colorado River Basin and as an example of watershed collaboration for decades to come.”
Carly Jerla, water resource engineer with Reclamation and co-manager of the Study, said the examination of the entire Basin has generated intense interest and scrutiny regarding its findings and what it presents as “options and strategies” for future water management. Before the Study could contemplate the tools for going forward, it had to depict an accurate picture of the challenge facing Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada and California.
“Before we could look at ways to help ensure future sustainability, we had to understand how unsustainable the river system could be if we do not take any action,” Jerla said. “It is widely known that the Colorado River, based on inflows observed over the last century, is over-allocated and supply and demand imbalances are likely to be exacerbated in the future.”
Elements of the Study that have been published are projections of future water supply and demand and the options received to resolve future imbalances. Projections of system reliability with and without options in place as well as an assessment of those options in terms of cost, yield, timing and other tradeoffs were forthcoming as Western Water went to press.
Representatives of the seven Basin states, which cost-shared the Study on a 50/50 basis with Reclamation, say the Study will be an important part of how water users face the future.
“The Study is groundbreaking for the Colorado River system on two fronts,” said Chuck Cullom, Colorado River programs manager with the Central Arizona Project. ”First, it was developed through a broad, direct collaboration-based approach, not only with the traditional players in the Colorado River system, but also Native American tribes, power providers, environmental advocacy groups and recreation interests. The Study incorporates the input from the broad range of stakeholders to provide a wider view of the values, resources, and interests to be considered in the Study.
“Second, the Study developed new modeling and analytical tools for water managers to use in the Colorado River system. The Study relies on a scenario-based approach considering multiple supply/demand/operations futures, and intentionally considers climate change information from down-scaled global circulation models to capture a broad range risks and vulnerabilities.”
Cullom said the Study “confirms what Colorado River water managers have long understood: the over-allocation of the Colorado River system coupled with increasing water needs and the potential for reduced supplies due to climate change will put the communities and resources relying on the river at significant risks of prolonged shortages in the future.”
Environmentalists say the Study is noteworthy for its candid assessment of the possible impacts on water supply brought about by climate change – about a median 9 percent reduction.
“It’s an affirmative recognition that climate change is a piece of what we have to look at and consider in thinking about the future of water supply and demand in this Basin,” said Jennifer Pitt, director of the Environmental Defense Fund’s Colorado River Project.
Pitt said it’s possible for water use needs to be met without constructing large infrastructure projects. “What we have in an approach that relies first and foremost on water conservation is a common sense strategy that meets demand and protects the river without requiring the big expensive projects,” she said.
Of course, dealing with a limited water supply is no mystery to Colorado River water users, who have gone out of their way to craft agreements to equitably distribute water.
“I think everybody realized we were in a deficit,” said Bruce Moore, director of surface water resources with the Southern Nevada Water Authority (SNWA). “If you just take the basic fact that the original Compact and the allocations were based on 17 to 17 and a half million acre- feet average annual supply, and it’s now averaging around 14 and a half to15 million acre-feet, you’ve already lost a million and a half to 2 million acre-feet of supply, so as the Basin begins to use all its water … you begin to realize that, ‘Gee, there really is an imbalance here, [and] what does that look like in the future?’”
The Study names a wide range of options and strategies that could be used to help ease the imbalance, including importing water from the Front Range to the Green River, seawater desalination in California and Mexico, brackish groundwater desalination, municipal and agricultural conservation, water recycling and rainwater harvesting. There has been ample discussion through the years about the merits of those and other ideas, all of which invite questions about feasibility and cost.
Cullom believes the Study can set the stage for water managers to aggressively plan for future supply scenarios. “We need to accelerate efforts to augment the Colorado River system, primarily through desalination efforts, and consider ways to bring more water to the system through delivery to the Front Range,” he said.
Jeff Kightlinger, general manager of the Metropolitan Water District of Southern California (MWD), said the Study takes “a first, hard look at what are the some of the feasible options to cooperatively grow water and deal with the issue of future shortages.”
“The results are there’s no real silver bullet out there,” he said. “The Study is a good compilation of the things and tools potentially out there, then you winnow down to what’s feasible and cost effective.”
Water conservation advocates say the first step should be reduced water use.
“Conservation is faster, it’s cheaper, more flexible, you can adapt as the climate adapts, as the population adapts,” said Drew Beckwith, water policy manager with Western Resource Advocates in Boulder, Colo. “You are not sinking hundreds of millions of dollars into an upfront project and having fixed loan repayments on something that may be antiquated five years after you build it.”
Projecting future demand is an inexact process, considering the many variables such as the pace of economic activity. Reclamation believes the Study presents a plausible range of future demands.
“Although each of the states developed population projections in a different manner and made assumptions about water use in a different manner, the types of parameters that drive demands are common to all of the Colorado River Basin states,” Jerla said. “We identified those parameters that are the key factors driving future demand, such as changes in population and water use, and then asked the states to tell us how those parameters would change under the Study’s six future demand scenarios.”
Pitt commended the Study for including a “substantial measure” of urban and agricultural water conservation in its package of options and strategies. That said, EDF is concerned about how water conservation is defined in the Study – how much can be achieved at what rate and at what cost. Furthermore, there has been “quite a bit of controversy” about the projected demands presented by the states, which are skewed toward the high side, Pitt said.
“It does absolutely matter what the demands are that you project,” she said. “It matters the population you project and the amount of conservation.”
Cullom said the Study also shows that targeted investments in augmentation projects and additional water conservation programs can protect the Colorado River and restore the river “so that it reliably and sustainably meets current and future water needs.” The options and strategies “operate within and are consistent with the existing framework provided by the Law of the River.”
The vast tourist-related industry associated with Colorado River recreational activities say it is vital that the region remains the destination of choice for the millions of people who annually visit. According to a study by Protect the Flows, a coalition of more than 400 small businesses throughout the seven states, river-related recreation supports 234,000 jobs in Arizona, Colorado, Nevada, New Mexico, Utah and Wyoming and produces $26 billion in economic output.
“The Study makes it clear just how much the Colorado River needs to watch its bottom line,” said Molly Mugglestone, Protect the Flows coordinator. “The West’s economic future is tied to this magnificent resource and the recreation it encourages, so we would do well to do all we can to protect it and to keep the river flowing.”
This issue of Western Water examines the Colorado River Basin Water Supply and Demand Study and what its finding might mean for the future of the lifeblood of the Southwest.
by Gary Pitzer
As we get ready for our 2013 water tour field trips, I’ve been thinking of some of the unique places we visit. These tours are an opportunity to see the natural environment, view water facilities and discuss issues with the people on the ground. And the tours are fun! People from all over California and the West spend two to three days together on busses and boats, walking around sites and sharing meals together. More than one water issue has been solved or moved along by people spending this kind of time together.
Our first major trip of the year is the Lower Colorado River Tour in March. So this issue of Western Water is good background for the trip. On the Colorado River, the stakeholders feud like all opposing parties but in recent years they have struck a variety of agreements beneficial to the entire Basin and Mexico. The opportunity to get a private tour of the majestic Hoover Dam alone is worth the trip. When I’m at the Dam, I like to think about author Joan Didion’s essay, Holy Water, in which she describes drawing water from her tap in Malibu and thinking of the water’s journey from the Colorado River through Hoover Dam, across the Mojave Desert eventually making its way to her faucet.
Sometimes we see the fruits of decisions by stakeholders and governmental officials. For example during our recent Northern California Tour in the Sacramento Valley, we saw salmon swimming in the riffles of Clear Creek, quite an inspiring sight since just a few years before the numbers of fish had declined significantly. On our San Joaquin River Restoration Tour, we visited Gravelly Ford, a portion of the river that had been dry since Friant Dam was built, and saw the river once again running its natural course due to restoration flows. This tour is a rare opportunity to see firsthand the sites involved in bringing back a major section of the river and learn about the reintroduction of salmon, farming concerns and the consequences of decisions. And, of course, I’m always struck by the breadth of issues and places covered on our Bay-Delta Tour. We follow the river flows through the Delta to San Francisco Bay and enjoy getting on the water during our ferry ride across the Bay. We also go to the U.C. Davis fish lab in the South Delta and see a Delta smelt research rearing facility. The scientists show us the delicate process of tagging and propagating the native fish that are considered key to the health of the Delta.
Another tour of particular interest is our Sea to Sierra Water Tour in April. This tour is a special opportunity to view California water and discuss the key issues while traveling across the state onAmtrak’s famed California Zephyr. Participants board the train in Oakland and travel from the edge of sparkling San Francisco Bay, through the meandering channels of the Delta, past rich Central Valley farmland, growing cities, historic mining areas and into the Sierra Nevada, then drop down the mountains and ride along the Truckee River into Reno. Other tours cover the Central Valley with its rich agricultural lands and flood issues Flood Management Tour in which we look at comprehensive statewide flood issues.