#Snowpack, #runoff and the #ColoradoRiver Basin — @MountainTownNew #COriver

Water rushes through scenic Glenwood Canyon. Photo/Colorado River Water Conservation District via The Mountain Town News -- Allen Best.
Water rushes through scenic Glenwood Canyon. Photo/Colorado River Water Conservation District via The Mountain Town News — Allen Best.

From The Mountain Town News (Allen Best):

Eric Kuhn paints a big picture of changing realities in the Southwest

rom his office in Glenwood Springs overlooking the Colorado River, Eric Kuhn has become one of the West’s most prominent thinkers about the intersection of water, climate change, and allocations for farms, factories and cities, including ski towns.

He joined the Colorado River Water Conservation District as an engineer after working in the private sector as a nuclear engineer. He has been manager of the water district since 1996. The district encompasses all of the Colorado River drainage in Colorado upstream from Fruita. As such, the district is a primary source of water not just for the bulk of Colorado ski towns and Front Range cities but also downstream farms and cities, including Phoenix, Los Angeles, and San Diego.

Mountain Town News collaborated with Kuhn on a reader-friendly Q&A to probe the growing evidence that warming temperatures have started upsetting the apple cart of Colorado River operations.

Eric Kuhn along the banks of the Colorado River in Glenwood Springs, general manager of the Colorado River District. Photo via the Grand Junction Daily Sentinel.
Eric Kuhn along the banks of the Colorado River in Glenwood Springs, general manager of the Colorado River District. Photo via the Grand Junction Daily Sentinel.

Was it a good snow year in the upper Colorado River Basin? It varied, of course, but generally it was average to a little above average in the Gunnison, Yampa, Green and other basins of the upper Colorado River.

Does that mean the reservoirs in the Colorado River Basin are filling? We’ve been hearing a lot about declining levels of Lake Powell and Lake Mead, the two giant reservoirs on the Colorado River. Water runoff is a more complicated story than snowpack. This year, for example, the runoff reached about 94 percent of average. So, average or above-average snowpack but below-average runoff.

The best way to understand snowmelt is to study the inflow into Lake Powell. You can call this reservoir the savings account for the Upper Colorado River Basin. It is this savings account that allows the upper division states of Colorado, Utah, Wyoming and New Mexico to consistently meet water supply obligations to the Lower Basin at Lake Mead as spelled out by the Colorado River Compact of 1922. The lower division states are California, Nevada, and Arizona.

There is no such thing as an average snow year—nowhere, no place. Snowpack varies wildly from year to year. That said, in an average water year, about 10.7 million acre-feet flows into Powell. Three-fourths of that occurs during April through July.

Colorado River Basin, USBR May 2015
Colorado River Basin, USBR May 2015

Average snowpack but below-average runoff? That poses an obvious question. But first, would you explain this savings account more? The 1922 compact requires the upper division states to not deplete the flows downstream to Lake Mead below a certain volume. Powell most often releases 8.23 to 9 million acre-feet, as required by the 2007 interim agreement among the seven basin states and the federal government, a side agreement to the compact. But ordinarily, because of evaporation, that means the effective demand on Powell is 8.6 to 9.4 million acre-feet.

What this means is that in any year with an 85 percent of average runoff, Lake Powell just about breaks even. In other words, water levels are not gaining but neither are they declining.

For local supply reservoirs in most of Colorado, we can get by with an 85 percent or better inflow year without too many concerns.

So nothing to worry about in the upper basin? We’re meeting our obligations, end of story? We are OK for now and probably for the immediate future, but if the current conditions transition into a drought over the next several years, as happened after the 1998 El Niño event, we could be in serious trouble because unlike in 1998-99 when system reservoirs were plumb full, today they’re only about half full.

How much of the water in Lake Powell and Lake Mead comes from upstream of Grand Junction (or Moab)? And how much of that originates as snow in places like Steamboat Springs, the Eagle Valley, and the San Juan Mountains? Most of the run-off in the upper basin originates from about 20 percent of the land: those watersheds above about 9,000 feet in elevation, where snowpack accumulates and sticks through the snow season.

The Green River drainage contributes 36 percent of the flow into Lake Powell, the Colorado mainstream 36 percent, the San Juan 24 percent, and the others 4 percent, according to the U.S. Bureau of Reclamation. This is the long-term average.

We’ve heard a lot about drought in the 21st century. Are we still in drought? Colorado as a whole is definitely not in a drought. From the entire Colorado River Basin perspective, it depends on the period one looks at. From 1906 through 2015, the mean annual flow at Lee’s Ferry (between Lake Powell and the Grand Canyon was 14.8 million acre-feet (maf). From 1930 forward, it’s been less, 13.9 maf, according to the National Flow Data Base kept by the U.S. Bureau of Reclamation (available on its website)

For the period of 2000 though 2015, the mean natural flow was 12.4 maf. That’s well below average. During the first part of the century, from 2000 through 2004, it was even less, just 9.4 maf.

Bottom line here: Nearly all the water in the Colorado River comes from upstream of the Grand Canyon, and the average in the 21st century has lagged below the longer-term averages of the 20th century.

Why are Lake Powell and Lake Mead continuing to decline? The recent declines in Mead have been caused by annual demand levels that exceed supply. By the end of 2016, I expect that total storage in Lake Powell and Lake Mead will be close to what it was at the end of 2005. Keep in mind that the major decline in runoff and hence storage was from 2000 through 2004.

Lake Powell via Aspen Journalism
Lake Powell via Aspen Journalism

That’s scary. Some decent snow years in the Rocky Mountains, where most of the Colorado River water comes from, but yet the storage in Mead is declining. Why the decline in Lake Powell?Lake Powell has actually gained a little bit of storage since 2013 and is well above the low point it reached in the winter of 2005. But because of obligations to deliver a little extra water to Lake Mead and because of OK-but-not-great inflows of 90 to 95 percent, the storage is not going up as rapidly as the snowfall in the Rocky Mountains suggests it should.

People talk about a “structural deficit.” What do they mean by that? The structural deficit is the difference between inflow to Lake Mead and demands at Lake Mead when Lake Powell is delivering a “normal” 8.23 maf/year. The math works this way: 8.23 maf from Powell plus native inflow between Powell and Mead of about 700,000 acre feet gives a total inflow of about 9 maf. Demands are 7.5 maf for the three Lower Basin states plus 1.5 maf for Mexico plus about 1.2 maf of evaporation and system losses for a total of 10.2 maf. Thus, the structural deficit is about 1.2 maf. Evaporation varies based on Lake Mead levels. When Lake Mead is fuller, evaporation plus system losses can be as high as 1.5-1.6 maf.

In a recent paper, you cited evidence that warming regional temperatures have turned above-average or abundant precipitation into just average runoff, kind of a reverse alchemy. How can this happen, turning more into less? Temperature is a major variable in the hydrologic cycle. As temperatures go up, evaporation goes up, crops and native vegetation consume more water (transpiration), and the runoff occurs earlier, which exposes native vegetation earlier. The net result is lower stream flows for the same precipitation levels. Brad Udall suggests that about one-half of the reduction in flows we’ve seen since 2000 in the Colorado may be due to temperature alone.

Good snow years means so-so water years in the Colorado River? Wow, that seems to have a lot of so-what! What do you think are the most important so-whats? For water supply purposes, it’s more than a so-what. If temperatures continue their upward trajectory (with year to year variability, of course), we may be in for a new normal. That normal may not have a ground floor.

I like statistics. Does one statistic leap to mind that illustrates what’s going on in the Colorado River Basin? Yes, the number is 1.2 million acre-feet, the amount that the Lower Basin (and Mexico) must reduce their demands if they are to stabilize levels in Lake Mead—at least for the moment. If temperatures continue to warm, they may have to reduce their demands even more.

Spray irrigation on a field in the Imperial Valley in southern California. This type of irrigation is a lot better than the extremely water inefficient type of flood irrigation that is popular in this region. Still, in the high temperatures of this desert region a lot of the water evaporates, leaving the salts, that are dissolved in the colorado River water that is used, on the soil.
Spray irrigation on a field in the Imperial Valley in southern California. This type of irrigation is a lot better than the extremely water inefficient type of flood irrigation that is popular in this region. Still, in the high temperatures of this desert region a lot of the water evaporates, leaving the salts, that are dissolved in the Colorado River water that is used, on the soil.

Why do California, Arizona and Nevada have to cut back—and we in the headwaters area don’t. The 1922 Colorado River Compact gave the upper basin states 7.5 million acre-feet, and the lower-basin states 8.5 maf. It was always assumed that California, in particular, but also Arizona would develop more rapidly, and they did, while the upper-basin states would be slower to put their allocated water to use. But, by the 1970s California was using far more than its 4.4 million acre-foot allocation. Since then, they have been reducing their diversions, but they remain above their allocation.

What are the implications for the headwaters in Colorado and Wyoming? We could continue to see good snow years and decent regional water supply conditions, but due to increasing regional temperatures and system-wide demands that exceed supplies, the Colorado as a whole may continue to be in crisis. There is an old saying that water flows uphill toward money. My biggest concern is that the continuing supply deficit may trigger efforts that will impact our quality of life, especially upper basin agriculture, which may be seen as the “low-hanging fruit.”

In your recent paper, you issue a warning. What is that warning—and is more than just one exclamation mark justified? My warning is that often, but not always, after we’ve had big El Niño years, in the next year, or two (or even three), we end up with drought in Colorado. 1997-98 and 1957-58 are good examples.

In Colorado, we need to quit talking about continuing drought and acknowledge that conditions in much of the state since the fall of 2013 have been wet (the Southwest and Rio Grande have not been as lucky). This means we need to be prepared for the NEXT drought. As (Colorado Water Conservation Board director) James Eklund says “wishing for the drought to end is not a successful strategy.”

For the basin as a whole, we need to be prepared to survive another 2000-2004 period. The difference is that in 1999 reservoirs were full to the brim. Now, they’re at levels of 40 to 50 percent of capacity.

It sounds like we will really need to rethink our use of water from Colorado and Wyoming to Arizona and California. Who’s in charge of this Plan B? The good news is that many entities are actively engaged in seeking solutions. The State of Colorado has just issued a water plan, for the first time ever. The lower division states appear to be on track to implement significant additional water savings if Mead levels continue to decline. Nobody is really in charge. The U.S. Secretary of the Interior has a significant role because of her authority over the operation of the major projects, but the states, affected water users, environmental groups, and the Native American tribes are all at the table.

In Lower #ColoradoRiver Basin, Small Fixes Are Hoped to Avoid the Big Fix — Colorado Public Radio #COriver

Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.
Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.

From Rocky Mountain PBS (Jim Trotter):

The river system, with its headwaters in Rocky Mountain National Park, has been stressed by drought since 2000. The most recent national climate assessment for the Southwest forecasts that the country’s hottest and driest region can only expect more of the same.

“This may be what the start of a water war looks like,” suggested a recent story in the Los Angeles Time.

The story by ace writer William Yardley focuses on negotiations between the lower basin states of California, Arizona and Nevada to voluntarily reduce withdrawals from Lake Mead in order to forestall the mandatory, more drastic cutbacks that most likely would come with a federal declaration.

Yardley calls the approach “tinkering.”

But Tom Buschatzke, director of the Arizona Department of Water Resources and one of the senior water managers on the river, says, “I like to describe this as another incremental step.”

The question is, can incremental steps preserve the governance of the river pretty much as is, defined by the Colorado River Compact of 1922 and modified by numerous laws and court decisions since?

“I don’t think a water war is inevitable,” Buschatzke tells Yardley.

The upper basin states generally and Colorado particularly are not as in dire shape as the lower basin states. As we’ve said before, Colorado has almost been in a bubble the past couple of years – average to above average snowpack, strong runoffs, filled reservoirs. But if water runs short for 25 million people in the lower basin, many of whom are in Southern California, no one can expect to remain untouched.

Yardley seems to admire the Arizona approach.

“But for Buschatzke,” he writes, “who has spent decades efficiently providing water for a desert population – Arizona uses less water now than it did 60 years ago even though the population has soared from 1.1 million to 6.7 million – the big fix is actually in the accumulation of all the little fixes he and others are constantly making. A federal grant for new technology that will better measure water use. Paying a farmer to fallow a field. Saying nice things about your colleagues across the state line and the fine folks in Washington. Keeping things collegial. Sharing. Saving. Preserving the process – and the peace.”

Obviously better than a new water war.

Delph Carpenter's 1922 Colorado River Basin map with Lake Mead and Lake Powell
Delph Carpenter’s 1922 Colorado River Basin map with Lake Mead and Lake Powell

#ColoradoRiver: Facing historically low levels, Lake Mead officials are fending off a water war — The Los Angeles Times #COriver

Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.
Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.

From The Los Angeles Times (William Yardley):

Drought is draining the West’s largest reservoir, Lake Mead, to historic low levels. Forecasts say climate change will make things worse. Headlines warn of water shortages and cutbacks. Members of Congress are moving to protect their states’ supplies.

Yet if war is really imminent, why is one of the region’s most experienced water managers doing the same thing he has done for years: tinkering?

“I like to describe this as another incremental step,” said Tom Buschatzke, director of the Arizona Department of Water Resources.

Buschatzke was talking about a plan he is helping develop, along with water managers in California, Nevada and Mexico, that would voluntarily reduce water allocations from the Colorado River to those three states and Mexico. They hope to have it in place in time to avoid steeper, mandatory cuts that could begin as soon as 2018.

Would their plan change everything? Would it finally fix the increasingly inadequate blend of canals, conservation and compromises that somehow keeps water flowing to more than 25 million people, including a substantial chunk of those in Southern California?

Not even close.

But for Buschatzke, who has spent decades efficiently providing water for a desert population — Arizona uses less water now than it did 60 years ago even though the population has soared from 1.1 million to 6.7 million — the big fix is actually in the accumulation of all the little fixes he and others are constantly making. A federal grant for new technology that will better measure water use. Paying a farmer to fallow a field. Saying nice things about your colleagues across the state line and the fine folks in Washington. Keeping things collegial. Sharing. Saving. Preserving the process — and the peace.

“I don’t think a water war is inevitable,” he said. “I think we’ve proven over the last 20 years that we can effectively work together to find solutions that really work. And as long as we continue to do that, the water war won’t happen.”

The current project, called the drought contingency plan, is a tweak to a previous tweak. Nearly a decade ago, water managers recognized that Lake Mead was draining faster than predicted. They recalibrated plans for how they could handle cutbacks. Now, with Lake Mead dropping even faster, they are recalibrating again.

The goal, as has been the case for years, is for water users to limit how much they take out of Lake Mead. The less they take, the less likely the lake will drop to levels that prompt mandatory cuts.

Yet the cuts would not apply evenly. Under an agreement reached in the 1960s, California is not required to make any cuts, even if the lake drops so low that Arizona and Nevada lose everything.

But now, even California is willing to conserve because officials know that, in the event of catastrophe, they will be forced to share anyway. It is better to try to prevent the catastrophe in the first place — and keep the federal government from taking over a process the states want to control.

There is no firm draft of the drought contingency plan, but the gist of it has been floated at meetings for several weeks. Under the plan, Arizona and Nevada would take cuts before California, but California eventually could take cuts too — again, with the goal of staving off even more severe cuts if it does nothing.

Buschatzke, who speaks weekly with managers in other states, said he thinks California has a new appreciation for Arizona’s endless search for efficiency.

“I think the drought in California, the severe impacts on the state water supply, have made them feel what it’s like to be Arizona,” he said.

The Colorado River Basin is divided into upper and lower portions. It provides water to the Colorado River, a water source that serves 40 million people over seven states in the southwestern United States. Colorado River Commission of Nevada
The Colorado River Basin is divided into upper and lower portions. It provides water to the Colorado River, a water source that serves 40 million people over seven states in the southwestern United States. Colorado River Commission of Nevada

#COWaterPlan: Time to get started on implementation

James Eklund and Governor Hickenlooper roll out the Colorado Water Plan, Thursday, November 19, 2015 via The Colorado Independent
James Eklund and Governor Hickenlooper roll out the Colorado Water Plan, Thursday, November 19, 2015 via The Colorado Independent

From The Denver Post (Jim Lochhead, Jon Goldin-Dubois):

The big question now is, what steps do we need to take to secure Colorado’s water future? The answer lies in Chapter 10: the “Critical Action Plan” that includes important, measurable objectives, goals and actions.

This chapter calls for reducing the future gap between water supply and demand by continuing water conservation and reuse efforts, incorporating water-saving actions into land-use planning, working to preserve agricultural economies while increasing flexibility and efficiency, creating stream and watershed protection plans, and increasing education and outreach.

These ideas are well thought out, reasoned and critical to implement. And the legislature took a few baby steps on some of these earlier this year. It legalized capturing rainwater through residential rain barrels, and it increased the ability of Front Range agricultural water users to retain their water rights but share some of their water with other users in times of need. The legislature also allocated $5 million to the CWCB to begin implementing the water plan.

However, now is not the time to claim success or, conversely, to throw in the towel. Now is the time to use the collective attention, work and energy of the tens of thousands of citizens who helped shape the plan and those who work daily on water issues in the state to push through critical parts of the plan to ensure a secure water future for Colorado.

Fortunately, we don’t have to reinvent the wheel to get this done. We have proven examples on how to kick-start, incubate, and work cooperatively to implement the water plan’s suggested actions.

For instance, the Colorado River Cooperative Agreement between Denver Water and West Slope local governments, water providers and ski areas will enhance the health of streams in the Colorado River Basin while allowing Denver Water to strengthen its system against drought and climate change by enlarging Gross Reservoir. As a result, the project actually benefits both sides of the Great Divide. Future projects like the expansion of Gross Reservoir that include appropriate mitigation are part of the solution. They should receive state support and funding because they can align with the state’s water values and the plan’s well-articulated criteria for being sustainable, collaborative and cost-effective. Indeed, the plan’s criteria should be applied to all project proposals — including the $5 million noted above — to ensure public funds are spent wisely.

Most importantly, we can take simple, immediate actions to increase water-use efficiency. The governor can accelerate reuse, graywater, and green infrastructure by funding the Colorado Department of Public Health and Environment to update its regulations. He can work to remove barriers to water reuse and green stormwater management and use. He can improve river health by setting a time frame for the CWCB and basin roundtables to establish priority lists of rivers that should have local stream management plans done. And, he can support water banks — to better facilitate sharing water for a multitude of purposes — in key river basins…

Jon Goldin-Dubois is president of Western Resource Advocates. Jim Lochhead was appointed Denver Water’s CEO and manager in 2010.

#ColoradoRiver: “Unprecedented high temperatures in the [#COriver] basin are causing the flow of the river to decline” — Brad Udall

The Colorado River Basin. The Upper Colorado River Basin is outlined in black.
The Colorado River Basin. The Upper Colorado River Basin is outlined in black.

From The Las Vegas Desert Sun (Ian James):

Lake Mead reached the new all-time low on [May 18, 2016] night, slipping below a previous record set in June 2015.

The downward march of the reservoir near Las Vegas reflects enormous strains on the over-allocated Colorado River. Its flows have decreased during 16 years of drought, and climate change is adding to the stresses on the river.

As the levels of Lake Mead continue to fall, the odds are increasing for the federal government to declare a shortage in 2018, a step that would trigger cutbacks in the amounts flowing from the reservoir to Arizona and Nevada. With that threshold looming, political pressures are building for California, Arizona and Nevada to reach an agreement to share in the cutbacks in order to avert an even more severe shortage.

“This problem is not going away and it is likely to get worse, perhaps far worse, as climate change unfolds,” said Brad Udall, a senior water and climate research scientist at Colorado State University. “Unprecedented high temperatures in the basin are causing the flow of the river to decline. The good news is that we have time and the smarts to manage this, if all the states work together.”

[…]

As of [May 19, 2016], the lake’s level stood at an elevation of about 1,074.6 feet. The federal Bureau of Reclamation, which manages the reservoir and Hoover Dam, projects the level to decline a few feet more to an elevation of about 1,071 feet by the end of June, before the level begins to rise again with releases of water from Lake Powell.

Under the federal guidelines that govern reservoir operations, the Interior Department would declare a shortage if Lake Mead’s level is projected to be below 1,075 feet as of the start of the following year. In its most recent projections, the Bureau of Reclamation calculated the odds of a shortage at 10 percent in 2017, while a higher likelihood – 59 percent – at the start of 2018.

But those estimates will likely change when the bureau releases a new study in August. Rose Davis, a public affairs officer for the Bureau of Reclamation, said if that study indicates the lake’s level is going to be below the threshold as of Dec. 31, a shortage would be declared for 2017.

That would lead to significant cutbacks for Arizona and Nevada. California, which holds the most privileged rights to water from the Colorado River, would not face reductions until the reservoir hits a lower trigger point.

Representatives of California, Arizona and Nevada said last month that they hope to have a deal finalized by the end of the year for all three states to accept cutbacks earlier than otherwise required in order to head off a more serious crisis.

Interior Secretary Sally Jewell has said she is optimistic about the talks, calling the over-allocation of the river a shared problem that must be solved. During a May 4 visit to Southern California, she said that there has been “extraordinary collaboration” between the states in working toward a deal, and that the United States and Mexico have also been making progress in negotiations on a new accord to share water from the Colorado River.

While representatives of the three states have discussed the outlines of proposals to temporarily take less water from Lake Mead, they say considerable hurdles remain, including negotiations between water districts within each state…

Scientists have estimated that rising temperatures and the resulting declines in runoff across the Colorado River Basin could reduce the river’s flow by between 5 percent and 35 percent by the middle of the century.

“Human-caused climate warming will drive larger and larger flow reductions as long as emissions of greenhouse gases continue,” said Jonathan Overpeck, co-director of the University of Arizona’s Institute of the Environment.

“The river is over-allocated even before climate change is factored in,” Overpeck said in an email. He said he thinks the negotiations will probably “focus on how to reduce the over-allocation, but will eventually have to focus on sharing the pain as climate change continues to reduce the flows.”

From Esquire Magazine (Charles P. Pierce):

The long-term prognostications are just uncertain enough to be terrifying. The American Southwest—and the Los Angeles area in particular—are natural deserts. Only the miracle of engineering has made them habitable. Quite simply, we created human space in a place that, left to its own devices, would have been suitable only by cactus and lizards.

Often when we think we’ve conquered nature, we find we’ve only held it to a tenuous draw.

Rifle “State of the River” meeting recap

Rifle Falls back in the day via USGenWeb
Rifle Falls back in the day via USGenWeb

From the Glenwood Springs Post Independent (Ryan Hoffman):

Conditions in the Upper Colorado River Basin, particularly in Colorado, are OK for the time being, officials said Wednesday during a “state of the river” address in Rifle.

However, the largest of several caveats to that statement falls in the context of the entire Colorado River Basin, specifically the lower basin, where water use continues to outpace supply.

Additionally, good flows and filling reservoirs in the Centennial state and in other areas of the upper basin — a region that includes western Colorado, eastern Utah, a sliver of Arizona and portions of Wyoming and New Mexico — are a sign that drier conditions loom in the future.

The combination of the two could lead to reductions in water usage, Eric Kuhn, general manager of the Colorado River Water Conservation District, said Wednesday.

The statement was not a prediction, Kuhn added, but a call for preparedness.

The cautionary note comes at a peculiar time basinwide.

“So right now … you’re … reading a lot of things about what’s going on in Arizona and the drought in California, the lower basin states are using too much water and they’re having to cut back — all of that is true,” Kuhn said. “But we’re kind of in an interesting situation. In Colorado conditions are OK to wet.”

Snowpack for the Upper Colorado River Basin was at 118 percent of average as of May 24, according to provisional SNOTEL data from the Natural Resources Conservation Service.

While the basinwide snowpack is less than the past two years, it is not “too far off normal,” said Nolan Doesken, Colorado state climatologist.

A streamflow forecast from NRCS predicts most of the Upper Colorado River Basin will hover around 100 percent of average May through July. And, Colorado’s reservoir storage statewide at the end of April was 112 percent of average.

Operations at two smaller storage reservoirs for the Upper Colorado River Basin, Green Mountain Reservoir in Summit County and Ruedi Reservoir east of Basalt, reflect average conditions, according to Victor Lee, hydrologic engineer for the Bureau of Reclamation’s eastern Colorado area office.

Green Mountain is expected to fill around July 10, and Ruedi is expected to fill around July 15.

While Colorado is looking “pretty darn good,” as Kuhn said, trouble lies downstream, where the combined storage in two of the nation’s largest reservoirs is declining.

Specifically, Lake Mead continues to see a drop in its water level to the point of a historic low. Water from Lake Powell has been released to stem Mead’s decline. A forecast from the Bureau of Reclamation predicts 9 million acre-feet of water could be released from Lake Powell in 2016 to help Lake Mead.

The problem, Kuhn said, is the demand in the lower basin is outpacing supply.

Numbers, shared Wednesday night, for Lake Mead’s water budget show an inflow of 9 million acre-feet, while outflow is 9.6 million AF. Evaporation claims another 0.6 million AF, which leads to a total deficit of 1.2 million AF.

While there has been a great deal of attention paid to the word “drought,” Kuhn said conditions on the Colorado River have mostly been stable since 2005.

“I would argue we’re not in a drought in the Colorado River Basin as a precipitation drought,” he said. “We may be in a drought because the demand exceeds supply in the system, especially in the lower basin.”

Should conditions worsen, it would exacerbate the situation.

As for when exactly conditions will worsen is uncertain, but Doesken said it could be right around the corner.

“This year we’re just cooking along as pleasant as can be, but what do you know about drought,” he asked. “It is always around the corner, so the longer we have little drought on the map the sooner we’ll be back into the next drought. … I guess I’d say that is a prediction.”

#ColoradoRiver: Lake Mead Record Low Reflects Changing American West — Circle of Blue #COriver

Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.
Lake Mead behind Hoover Dam December 2015 via Greg Hobbs.

From Circle of Blue (Brett Walton):

Nervous investors, concerned about their nest eggs, will check the financial markets. Is the New York Stock Exchange up? What direction is the NASDAQ moving?

For people living in the American Southwest, water levels in reservoirs play the same role. And Lake Mead is the blue chip, the biggest, most consequential, most widely watched piece in the game. When water levels are up, spirits are unburdened. People are confident in their place in the desert.

But when water levels are down, a cloud of worry creeps in, bringing questions about the fragility of life in the drylands. Down, way down, is where Lake Mead is today. On May 18, just before sunset, the surface elevation of America’s largest reservoir crossed the 1,074.7 foot threshold, setting a new record low for the iconic water body. The next day another record low was set. In fact, every day since then the reservoir has broken the old mark. The Bureau of Reclamation, the federal agency that manages Mead, expects the daily decline to continue through June. The reservoir is 36 percent full — or, to look at it another way, 64 percent empty.

Public worry has evolved to a transcendent regional anxiety, and moving the Southwest to action. Communities are investing in new equipment and partnerships in order to adapt to the basin’s new math. Las Vegas spent nearly $US 1.5 billion to construct a water intake at the bottom of the lake and a pumping station to lift the water. Los Angeles, which is outside the basin but gets Colorado River water delivered by canal, is cutting reliance on imported water. Phoenix and Tucson, often viewed as ideological opposites, agreed in 2014 to coordinate the use of their water facilities, to maximize storage and minimize cost. Most remarkable of all, California — which holds the most power in the basin and the most secure rights — is in talks with Arizona and Nevada on a new conservation agreement. That agreement would reduce California’s annual take of the Colorado River for the first time.

Mead started to tumble at the turn of the 21st century, when drier conditions took hold in the Colorado River Basin. With every new annual low the sense of urgency in the seven-state, two-country watershed grew. A landmark 2007 agreement worked out a formula for declaring a shortage in the lower basin states of Arizona, California, and Nevada, and for restricting water withdrawals from Mead. The three states are now working to delay that day of reckoning by keeping more water in the big reservoir.

A reckoning is imminent. The climate and the Colorado are drying. There are proposals from the upper basins states — Colorado, New Mexico, Utah, and Wyoming — to take more water out of the river, which will reduce flows into Lake Mead. Utah filed a federal application earlier this month for a pipeline to draw water from Lake Powell, located upstream from Mead.

Topography is another complication. Because the canyon that holds the lake is v-shaped, water levels fall more quickly near the bottom. Every one-foot drop in elevation equates to 80,000 acre-feet of water lost — an acre-foot is 326,000 gallons — or more water than San Francisco uses in a year. It all adds up to a long-term forecast of diminishing supplies.

There is no time to waste. The timetable for action is accelerating. The record lows are coming sooner in the season – July 9, 2014; June 23, 2015; May 18, 2016. All eyes are on the number 1,075. If Mead’s elevation in August is projected to be lower than 1,075 feet at the start of the following year, then a shortage would be declared. The Bureau of Reclamation estimates a 56 percent chance of a lower basin shortage by 2018. This means water cuts from the Colorado for Arizona and Nevada (and potentially for California, depending on how the ongoing negotiations shake out).

Despite the gloomy forecast, there are encouraging signs of camaraderie. A shortage would have come sooner if not for concerted conservation efforts in recent years. A $US 11 million program that was agreed to in 2014 is paying for conservation projects that bank the saved water in Mead. A similar program is taking place in the upper basin.

All told, a shortage will not decimate the basin. Its punch is more psychological at the moment than physical. But it is symbolic of the difficulty ahead if Lake Mead drops below 1,050 feet, or 1,025 feet, or even near the 950-foot level where hydropower generation would cease. The sternest tests for the Colorado River Basin — both political and hydrological — are still to come.