Western states buy time with a 7-year #ColoradoRiver #drought plan, but face a hotter, drier future — The Conversation #DCP #COriver #aridification

The white “bathtub ring” around Arizona’s Lake Mead (shown on May 31, 2018), which indicates falling water levels, is about 140 feet high. AP Photo/Ross D. Franklin via The Conversation

From The Conversation (Brad Udall, Douglas Kenney, John Fleck):

As Midwest states struggled with record spring flooding this year, the Southwest was wrestling with the opposite problem: not enough water. On May 20, 2019, federal officials and leaders from seven states signed the Colorado River Drought Contingency Plan, a sweeping new water management agreement for this arid region.

The plan is historic: It acknowledges that southwestern states need to make deep water use reductions – including a large share from agriculture, which uses over 70% of the supply – to prevent Colorado River reservoirs from declining to critically low levels.

But it also has serious shortcomings. It runs for less than a decade, through 2026. And its name – “Drought Contingency Plan” – suggests a response to a temporary problem.

As scholars who have spent years researching water issues in the West, we know the Colorado River’s problems are anything but temporary. Its waters have already been over-allocated, based on a century of false optimism about available supply. In other words, states have been allowed to take out more than nature puts back in.

Now the river is being further depleted by climate change-driven aridification. The next steps, post-2026, require a recognition that Arizona, Nevada and California will likely have to come to terms with permanent reductions in their Colorado River supply. For their part, Wyoming, Utah, Colorado and New Mexico must abandon dreams of taking ever-larger gulps from the Colorado River to support future growth.

The Colorado River is about 1,400 miles long and flows through seven U.S. states and into Mexico. The Upper Colorado River Basin supplies approximately 90 percent of the water for the entire basin. It originates as rain and snow in the Rocky and Wasatch mountains. Credit USGS.

Draining western reservoirs

The Drought Contingency Plan is an important step in that direction. By creating a new layer of rules that temporarily reduces water allocations, it significantly reduces the chance of emptying Lake Mead, the massive reservoir on the Arizona-Nevada border that supports residents of Arizona, Nevada, California and Mexico. Without the plan, the lake conceivably could have been sucked dry – a devastating prospect for 40 million people who live in the Colorado River Basin.

As a seven-year stopgap, the plan comes just in time. After 19 years of unprecedented low flows, the nation’s two largest reservoirs – Lakes Mead and Powell – collectively contain only 40% as much water as they held in 2000. And while the winter of 2018-2019 was a big snow year, it merely balances the previous year, when record-setting warm and dry weather in large parts of the basin lowered water levels in Lake Powell by over 40 feet.

Dry years like 2018 are the far more likely future. From 2000 through 2004, annual runoff totaled only 65% of the 20th-century average. And in 2012-2013, it was just 60% of the 20th century average. More episodes like these would seriously compromise the system’s ability to provide water to the seven Colorado River Basin states and Mexico.

A hotter, drier future

Climate change is and will remain a significant issue. Since 2000, Colorado river flows have been 16% below the 20th-century average. Temperatures across the Colorado River Basin are now over 2 degrees Fahrenheit warmer than the 20th-century average, and are certain to continue rising.

Scientists have begun using the term “aridification” to describe the hotter, drier climate in the basin, rather than “drought,” which implies a temporary condition.

Studies show that higher 21st-century temperatures have been reducing runoff. Warmer temperatures increase evaporation from soils and water bodies, and increase sublimation from snowpacks – direct conversion of snow and ice into fog or steam, without melting first. And they increase plant water use, due to a longer growing season and more warmth on any given day.

In a 2017 study, one of us (Brad Udall) and Jonathan Overpeck found that higher temperatures due to climate change had reduced the flow of the Colorado River by approximately 6%. The study projected that additional warming could reduce flows by approximately 20% in 2050 and up to 35% by 2100 if precipitation levels did not change. A 2018 modeling study estimated the flow losses due to higher temperatures at about 10%.

Overuse in the Lower Basin states of Arizona, Nevada and California is the second major problem. This problem is officially known as the “Structural Deficit” – a 1.2 million acre-foot gap, representing 8% of the river’s flow, between allocations made in the early 20th century and the amount of water the river can provide.

Cities from Las Vegas on the north to Tucson and Phoenix on the south and west to San Diego and Los Angeles all have come to depend on that water. Meanwhile, agriculture – including important areas like Yuma and the Imperial Valley, where much of the nation’s valuable winter produce is grown – uses 70% of the river’s water.

The All American Canal diverts water from the Lower Colorado River to irrigate crops in California’s Imperial Valley and supply 9 cities. Graphic credit: USGS

Looking past 2026

With the contingency plan only running until 2026, Basin leaders are already discussing the framework of a new planning effort. In our view, the process should be open and inclusive, given the huge number of competing interests in the region, including municipalities, agriculture, tribes and the environment.

An effective long-term plan should solve the overuse problem in the Lower Basin, while preparing for extended and unprecedented low flows. It should revisit a number of long-standing assumptions about how the river is managed, including the Upper Basin’s so-called “delivery obligation” to the Lower Basin, which leaves the upper states – Wyoming, Utah, Colorado and New Mexico – bearing the burden of climate change, while the Lower Basin states remain free to overuse. And it will have to address the reality that there is not enough water for users in the Upper Basin to continue exporting ever more water to growing cities like St. George, Utah, and Colorado’s Front Range.

Solving the twin problems of climate change and overuse will not be easy. The good news is that water users in the basin have found ways to work together for everyone’s benefit, first in a set of water management guidelines negotiated in 2007, and then with the Drought Contingency Plan.

Now, after staving off worry that system reservoirs could drop to calamitous levels, water users and managers can focus on these pressing longer-term issues. It is time to step back, look at the big picture and design a water management system that works for all stakeholders in the basin for the next several decades.

Brad Udall, Senior Research Scientist, Colorado Water Institute, Colorado State University; Douglas Kenney, Senior Research Associate and Director, Western Water Policy Program, University of Colorado, and John Fleck, Professor of Practice in Water Policy and Governance and Director, Water Resources Program, University of New Mexico

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Dividing the waters: How a compact call might unfold on Western Slope — @AspenJournalism #ColoradoRiver #COriver #aridification

A chart from the Colorado River District’s Phase III risk study, showing average annual depletions from the Western Slope, including transmountain diversions, tied to both pre and post compact rights. Graphic credit: Colorado River District via Aspen Journalism

From Aspen Journalism (Brent Gardner-Smith):

Coloradans use, or deplete, an annual average of 2.5 million acre-feet of water from the state’s various river basins that send water down the Colorado River system to Lake Powell, according to a new study on water use and water rights presented [June 25, 2019] in Grand Junction by the Colorado River District to more than 130 water managers and users.

Of the 2.5 million of annual average consumptive use, the study found that 1.6 million is tied to pre-Colorado River Compact water rights that are not subject to curtailment under the terms of the 1922 compact, which requires that the upper-basin states of Colorado, Utah, Wyoming and New Mexico send a certain amount of water to the lower-basin states of California, Arizona and Nevada.

But that leaves 932,000 acre-feet of current consumptive water use that is subject to compact curtailment, because the use of the water is tied to post-compact water rights.

The study, which drills down into water use in the various river sub-basins on the Western Slope, found that of the 932,000 acre-feet of post-compact water use, 626,200 acre-feet is from the “Colorado River Mainstem Basin,” which includes the main stem of the Colorado and the tributaries that drain the Roaring Fork, Eagle, Blue and Fraser river basins in Pitkin, Eagle, Summit and Grand counties.

The Upper Colorado River Basin, or that section of land drained by the Colorado River, within the state of Colorado, above the Colorado River’s confluence with the Gunnison River. This basin is regulated by the state of Colorado as Division 5, and the state’s regional water court and water engineer’s office are located in Glenwood Springs. Graphic credit: Colorado River District via Aspen Journalism

Exporting water

The Colorado River Basin, for the purposes of water-rights administration, is defined by the state as Division 5. And it accounts for virtually all of the transmountain diversions from the Western Slope to the Front Range.

Of the 626,200 acre-feet of average annual post-compact use in the Colorado River basin, 532,000 acre-feet is attributed to transmountain diversions.

This isn’t breaking news for Front Range water managers, who have long known that their water from the Western Slope is based on post-compact water rights.

“I would be very surprised if any of this is a surprise to them,” said John Carron of Hydros Consulting Inc. in Boulder. He is the engineer managing the study and its complex hydraulic model, which are being paid for by both the Colorado River District and the Southwestern Water Conservation District in Durango.

But the numbers in the study showing the high reliance on post-compact water rights help illustrate how intertwined the Western Slope and the Front Range are in the face of a compact call.

“This really is a statewide issue, not just a West Slope issue, just by virtue of the fact that 60% of post-compact use in Colorado is by transmountain users,” John Currier, the river district’s chief engineer, said at Thursday’s meeting.

This graphic shows the transmountain diversions in Colorado.

Risk factors

The study also sought to determine whether future depletions from the larger Colorado River upper-basin river system would increase the likelihood of a compact call, based on the hydrology recorded from 1988 to 2015.

The upper basin is supposed to deliver between 8.25 and 7.5 million acre-feet a year to the lower basin, depending on how the compact is interpreted.

The model used in the study found that if new depletions increased by 12%, it would increase the likelihood of compact call by 46% — if the goal was to deliver 8.25 million acre feet year to the lower basin, or 82.5 million acre-feet on a 10-year running average.

If the goal was to deliver 7.5 million acre-feet a year, or 75 million acre-feet on a 10 year running average, the model indicated a 0% increase in risk, primarily because of a new agreement to use reservoirs upstream of Lake Powell, mostly Flaming Gorge Reservoir, to send water downstream.

But, Carron noted, “all models are wrong, some are useful,” and said the risk of a compact call could be higher if there is less water in the future than the amount used in the model.

The outflow of the Bousted Tunnel just above Turquoise Reservoir near Leadville. The tunnel moves water from tributaries of the Roaring Fork and Fryingpan rivers under the Continental Divide for use by Front Range cities, and Pitkin County officials have concerns that more water will someday be sent through it.

Priority dates

The study also asked if a compact call were to materialize, how far down a list of post-compact water rights, prioritized by dates, would the state have to curtail in order to send significant amounts of water downstream?

The study found that if the state needed to send 100,000 acre-feet downriver to the lower basin, it would have to curtail post-compact water rights dating back to July 1957.

That’s a notable date, because the water rights for the Fryingpan-Arkansas Project — which diverts about 52,000 acre-feet a year from the headwaters of the Fryingpan and Roaring Fork rivers — have a 1957 priority date and could be curtailed early in the process.

If the state needed to send 300,000 acre-feet downriver, it would need to curtail rights dating back to September 1940, and that could curtail Denver Water’s diversions from Dillon Reservoir through the Roberts Tunnel, which are made under water rights with a 1946 priority date.

If the state needed to send 600,000 acre-feet, it would require curtailing post-compact rights dating back to August 1935, which could curtail the rights from 1935 that allow water to flow through the Adams Tunnel to northern Colorado.

The crowd of water managers and users gathered on June 20, 2019 at the Ute Water Conservancy District to hear the latest on the Colorado River District’s risk study. Photo credit: Brent Gardner-Smith/Aspen Journalism

Water use

The study also provides an overall portrait of how Coloradans are using water from the Western Slope basins.

Of the 2.5 million acre-feet of water that Coloradans are now using from the state’s rivers that send water down to Lake Powell, including use tied to both pre- and post-compact rights, 1.2 million acre-feet is being depleted from the Colorado River Basin, or Division 5.

Of that 1.2 million acre-feet, 669,000 acre-feet is going toward in-basin uses, such as irrigation in the Grand Valley, and 551,000 acre-feet is going toward transmountain diversions.

Depletions in the other Western Slope basins include 552,000 acre-feet from the Gunnison River basin; 501,000 acre-feet from the Southwest basin, which includes the Dolores and San Juan rivers; 197,000 acre-feet from Yampa River basin; and 62,000 acre-feet from the White River basin.

When it comes to water within each Western Slope basin, most of the water being depleted from the rivers is going to grow hay, grass and alfalfa, with smaller portions being used to irrigate orchards and row crops, and still smaller portions being used to provide water to people and their lawns in cities and towns.

About 600 cfs of water from the Roaring Fork River basin flowing out of the east end of the Twin Lakes Independence Pass Tunnel on June 7, 2017. Photo: Brent Gardner-Smith/Aspen Journalism

Front Range options

Most water users in Colorado are now considering ways to use less water, and most also are concerned about new uses in the system, which could hasten a compact call.

But a specific concern for the Western Slope arises from the Front Range’s heavy reliance on post-compact transmountain diversions, which account for about 60% of Front Range use.

Front Range water managers seem to have two options in the face of a compact call: Buy up land on the Western Slope with senior water rights, and then fallow the land and send the water downstream; or ask the state to not strictly apply the priority system, based on the dates of water rights, in order to avoid junior, post-compact, rights being curtailed.

Either way, the reliance by the Front Range on post-compact water rights is expected to ripple right back to the Western Slope.

“It’s time to start talking with our colleagues on the Front Range,” Jim Pokrandt, the river district’s director of community affairs and the chair of the Colorado Basin Roundtable, said at the conclusion of Thursday’s meeting.

Barbara Biggs, the chair of the Metro Basin Roundtable, which includes the Denver metro area, was at Thursday’s meeting, and she concurred with Pokrandt.

“Talking is always better than not talking,” Biggs said. “And planning is always better than not planning.”

Aspen Journalism covers rivers and water in collaboration with The Aspen Times. The Times published this story on Monday, June 24, 2019.

Video: 40th Annual GWC Summer Conference Day 1

Session One: The Pre-Amble to IG 2.0
The Interim Guidelines introduced major changes in river management, and established an operational framework and collaborative environment supporting additional reforms, including the recent DCPs (Drought Contingency Plans). How does this background inform and influence the path forward to new rules?

Delph Carpenter’s Preferred Compact — @R_EricKuhn #ColoradoRiver #COriver #aridification

Here’s a historical look at the Colorado River Compact and Delph Carpenter’s influence from Eric Kuhn that’s running on InkStain. Click through and read the whole post for Eric’s insights. Here’s an excerpt:

The 1922 compact as it was signed in November 1922 was not the compact Carpenter wanted when the negotiations began in the previous January. He was a fierce advocate for state sovereignty over all the waters that originate or flow through a state, but Carpenter knew he might be on the wrong side of the United States Supreme Court on the matter…

In the early 1900s, A Colorado developer proposed a project that would divert water from the Laramie River Basin into the adjacent South Platte River Basin. In 1911, Wyoming went to the U. S. Supreme Court to protect water rights that had already been perfected in the Wheatland area. As the Colorado River negotiations began, the case had been through two oral arguments, but had not yet been formally decided. Carpenter feared that since both Colorado and Wyoming were prior appropriation states, the court would apply the doctrine to the Laramie on an interstate basis, undermining his cherished state sovereignty and, on the Colorado River, giving the advantage to faster growing lower river states.
The Laramie case loomed as representatives of the seven Colorado River Basin states came together to negotiate what would become the Colorado River Compact.

After joining Utah commissioner R. E. Caldwell during the sixth Compact Commission meeting to block a proposal to apportion water to individual states based on the amount of irrigable acreage within each state, during the seventh meeting, Carpenter made his move. Carpenter’s proposal was relatively simple. He suggested that the lower river states should allow the upper river states to develop and use water within the basin unimpeded by the states of the lower river –“the construction of any and all reservoirs or other works upon the lower river shall in no manner arrest or interfere with the subsequent development …of the upper states or the use of water therein….”

In return, Carpenter said, the upper river states would do the same- “give you absolute free unbridled rights, all objections withdrawn…” The upper river states would not litigate or oppose in Congress, any development in the lower river. Carpenter made the case that due to the canyon and mountainous topography, climate (limited growing season), and because of return flows, water use within the upper part of the basin would have little impact on the supply of water to the lower river- “the areas which may be irrigated and the consumption …. so limited by nature, that the states of origin will never be able to beneficially use even an equitable portion of the waters …. of each.” When pressed by Commission Chairman Herbert Hoover, Carpenter acknowledged that because exports out of the basin were fully consumptive the upper river would agree to limit the amount water moved across the continental divide. In Silver Fox of the Rockies, historian Daniel Tyler suggests that Carpenter and his fellow upper river commissioners would have accepted a limit of 500,000 – 600,000 acre-feet per year, about 25% less than the current exports.

Commissioners from the lower river rejected Carpenter’s proposal countering that without an overall limit on upper river use, they would not have the certainty necessary to finance their proposed projects. In June 1922, the Supreme Court unanimously ruled in favor of Wyoming and applied the concept of prior appropriation to the Laramie River as a whole, confirming Carpenter’s fears. The decision forced him to change tactics. When the commissioners reconvened in Santa Fe in November 1922, building on a proposal by the Reclamation Service’s Arthur Powell Davis (now Bureau of Reclamation) to create a compact among the two basins, Carpenter made a new proposal which became the framework for the compact that was ultimately approved. Carpenter proposed the basins be divided at Lee Ferry (a mile downstream of Lee’s Ferry), the Upper Basin would, in Carpenter’s words, “guarantee” a 10 year-flow at Lee Ferry (the negotiated number ended up at 75 million acre-feet), and each basin would share any future treaty obligation to Mexico…

In theory, new export projects out of the Upper Basin to meet the needs of the booming Colorado Front Range and Wasatch Front could be a driver for new consumptive uses, but reality suggest otherwise. There are currently only three export projects in the planning or permitting process; Denver Water’s Moffat System Expansion project, Northern Water’s Windy Gap Firming project, and the State of Utah’s Lake Powell Pipeline. The net additional consumptive of the first two projects is small, no more than about 20,000 acre-feet per year. The Lake Powell Pipeline will divert about 80,000 acre-feet per year to the St. George area, but it may not really be an export project. The water it diverts will be used in the Lower Basin. Like overall Upper Basin consumptive uses, since 1988 the trend for exports has been flat or slightly declining…

The current situation on the river raises the basic question of equity between the two basins that Carpenter recognized a century ago. The Lower Basin is using more than its 8.5 million acre-feet apportionment under the 1922 compact. The Upper Basin is using far less than its 7.5 million acre-feet, about 4.3 million acre-feet per year. Yet, with fixed obligations to the Lower Basin and Mexico under the 1922 compact, the Upper Basin still bears the brunt of the climate change risk.

Eric and his co-author, John Fleck, have written a new book Science be Dammed: How Ignoring Inconvenient Science Drained the Colorado River. Most Colorado River watchers have the book on their wish list. Click here to pre-order. Publication is slated for later this summer. Here’s a blurb from the Tattered Cover Bookstore website:

Description

Science Be Dammed is an alarming reminder of the high stakes in the management—and perils in the mismanagement—of water in the western United States. It seems deceptively simple: even when clear evidence was available that the Colorado River could not sustain ambitious dreaming and planning by decision-makers throughout the twentieth century, river planners and political operatives irresponsibly made the least sustainable and most dangerous long-term decisions.

Arguing that the science of the early twentieth century can shed new light on the mistakes at the heart of the over-allocation of the Colorado River, authors Eric Kuhn and John Fleck delve into rarely reported early studies, showing that scientists warned as early as the 1920s that there was not enough water for the farms and cities boosters wanted to build. Contrary to a common myth that the authors of the Colorado River Compact did the best they could with limited information, Kuhn and Fleck show that development boosters selectively chose the information needed to support their dreams, ignoring inconvenient science that suggested a more cautious approach.

Today water managers are struggling to come to terms with the mistakes of the past. Focused on both science and policy, Kuhn and Fleck unravel the tangled web that has constructed the current crisis. With key decisions being made now, including negotiations for rules governing how the Colorado River water will be used after 2026, Science Be Dammed offers a clear-eyed path forward by looking back.

Understanding how mistakes were made is crucial to understanding our contemporary problems. Science Be Dammed offers important lessons in the age of climate change about the necessity of seeking out the best science to support the decisions we make.
About the Author

Eric Kuhn [@R_EricKuhn] , recently retired, worked for the Colorado River Water Conservation District from 1981 to 2018, including twenty-two years as general manager. The district is a water utility and policy agency covering most of the Colorado River basin within Colorado.

John Fleck [@jfleck] is director of the University of New Mexico’s Water Resources Program. A Colorado River expect, he wrote Water Is for Fighting Over and Other Myths About Water in the West.

Praise For…

“Highly significant for understanding the present water supply issues of the southwestern United States.”—Victor Baker, Hydrology and Water Resources, University of Arizona

#ColoradoRiver Compact obligations put #FrontRange transmountain diverters and Upper Basin in general at highest risk if there is a call #COriver #aridification

Here’s a report from Dennis Webb writing for The Grand Junction Daily Sentinel. Click through and read the whole article. Here’s an excerpt:

Upper Colorado River Basin water users are the most vulnerable on the Western Slope in the event of a call required by an interstate compact to curtail use, with much of that vulnerability resting with entities that divert water from that basin to the Front Range, new analysis shows.

John Carron, with Hydros Consulting, presented the latest work on potential risks facing the Western Slope in the case of continued long-term drought to a joint meeting of the four West Slope Basin Roundtables at the Ute Water Conservancy District in Grand Junction Thursday. This is the third phase of an analysis being conducted for West Slope water entities of risk arising from possible future water supply and demand levels.

Modeling used in the phase-three analysis found a 46 percent chance that over the next 25 years, the running 10-year average flow just below Lake Powell could fall below 82.5 million acre-feet. That threshold accounts for the average 7.5 million acre-feet a year that states in the Upper Colorado River Basin must allow to reach Lower Basin states over any 10-year period, plus another 750,000 acre-feet a year obligated to Mexico under a treaty.

Notably, the study finds that the risk doubles if annual Upper Basin water consumption increases an average of 11.5 percent a year…

New Mexico resident John Fleck…wrote a preview on Carron’s presentation last week on his blog, www.inkstain.net/fleck/. Fleck wrote that if average 10-year flows drop below 82.5 million acre-feet, “all sorts of hell could break loose, in court and/or as Colorado and other states scramble to cut back uses to meet downstream delivery obligations.”

[…]

A compact call is of most concern to those with water rights junior to 1922, when the interstate river compact was finalized. The Hydros study found that Colorado uses an average of about 2.5 million acre-feet of Colorado River water each year, with about 1.6 million of that involving pre-compact water rights, and some 932,000 acre-feet involving post-compact rights.

The upper Colorado River Basin accounts for about 626,000 acre-feet of post-compact water use, followed by southwest Colorado basins at 178,000 acre-feet, and the remainder spread between the Yampa, White and Gunnison basins. But about 532,000 acre-feet of the post-compact depletions within the upper Colorado basin are attributable to transmountain diversions, or about 57 percent of total post-compact depletions in the state, according to the report.

A curtailment of uses wouldn’t necessarily involve all 932,000 acre-feet of post-compact water in Colorado. The Hydros study dives into questions such as what are the oldest water rights (July 1957) that would be affected if 100,000 acre-feet were called, 300,000 acre-feet (September 1940), and 600,000 acre-feet (August 1935). It also breaks out the impact by acre-feet for each Colorado River sub-basin to reach each of those partial curtailment levels.

For purposes of discussion, and not because Hydros is advocating the idea, the report also explores the possibility that a curtailment in Colorado might be applied in some way other than simply on a statewide basis according to the age of water rights.

As its example, it calculates mandatory reductions in use based on each sub-basin’s post-compact water use as a percentage of statewide post-compact use.

Under such an approach, as an example, in the case of a 300,000 acre-foot statewide curtailment, the Gunnison Basin would be responsible for 18,436 acre-feet of that total, compared to 20,862 acre-feet if its percentage of overall use wasn’t considered. But southwest Colorado basins would be on the hook for about 57,000 acre-feet, about 17,000 more than when not considering sub-basin percentage of use.

On Stressed #ColoradoRiver, States Test How Many More Diversions Watershed Can Bear — KUNC #COriver #aridification

Gross Reservoir — The Gross Reservoir Expansion Project will raise the height of the existing dam by 131 feet, which will allow the capacity of the reservoir, pictured, to increase by 77,000 acre-feet. The additional water storage will help prevent future shortfalls during droughts and helps offset an imbalance in Denver Water’s collection system. With this project, Denver Water will provide water to current and future customers while providing environmental benefits to Colorado’s rivers and streams. Photo credit: Denver Water

From KUNC (Luke Runyon):

The Colorado River is short on water. But you wouldn’t know it by looking at a slate of proposed water projects in the river’s Upper Basin states of Colorado, Utah and Wyoming.

The river and its tributaries provide water for 40 million people in the Southwest. For about the last 20 years, demand for water has outstripped the supply, causing its largest reservoirs to decline.

In the Bureau of Reclamation’s 2012 Colorado River Basin Water Supply and Demand Study, you can pinpoint when the lines crossed somewhere around the year 2002. It’s a well-documented and widely accepted imbalance.

That harsh reality — of the river’s water promised to too many people — has prompted all sorts of activity and agreements within the seven Western states that rely on it. That activity includes controversial efforts in some states in the Colorado River’s Upper Basin to tap every available drop before things get worse.

The utility that owns [Gross Reservoir], Denver Water, wants to increase the size of the dam by 131 feet, and fill the human-made lake with more water from the headwaters of the Colorado River via a tunnel that traverses the Continental Divide.

Imagine a tractor trailer hauling dam-building materials making this turn, Long says.

“If they truck all of this material up our canyon, people in our community are gonna get killed by those trucks. Period,” Long said. “There’s a lot of other issues here but the safety thing should really be a serious priority.”

Long and his wife, April Lewandowski, live near the reservoir in a community called Coal Creek Canyon. Like many of her neighbors, Lewandowski commutes from the sparsely populated canyon to her job on the state’s dense Front Range. Her daily commute on the canyon’s two-lane highway is the same as a haul route for trucks needed to build the dam addition.

Long pulls up to a small parking area that overlooks the dam. It’s a deep wall of concrete, stretched between the tree-lined canyon walls of South Boulder Creek.

“I mean you look at how the land splays out, you can see why they want to (build it),” Long said. “It’s so much wider all the way around.”

If the expansion goes through, the place where we’re standing will be submerged in water. The addition to Gross Dam will raise it to 471 feet in height, making it the tallest dam in Colorado…

Denver Water first started taking an expansion of Gross Reservoir seriously after the dry winter of 2002. Exceptional drought conditions took hold across the Mountain West. The utility’s CEO, Jim Lochhead, said in the midst of those historic dry conditions, a portion of its service area nearly ran out of water.

“This is a project that’s needed today to deal with that imbalance and that vulnerability and to give us more drought resiliency,” Lochhead said.

Since then, Denver Water has filed federal permits to start construction, and negotiated an agreement with local governments and environmental groups on the state’s Western Slope to mitigate some effects of the additional water being taken from the headwaters.

Before leaving office, former Colorado Democratic governor and current presidential hopeful John Hickenlooper threw his weight behind the project, giving it an endorsement and suggesting other water agencies in the West take notice how Denver Water approached the process.

But despite the political heft behind the project, it faces considerable headwinds.

Environmentalists are suing, arguing the expansion will harm endangered fish. A group of local activists say the additional water will spur unsustainable population growth along the state’s Front Range. In recent months, the utility began sparring with Boulder County officials over whether they were exempt from a certain land use permit.

Building a 131-foot dam addition does come with baggage, Lochhead said. But he argued his agency has done its part to address some of the concerns, like reducing the number of daily tractor trailer trips up Coal Creek Canyon and planning upgrades to the intersection where trucks will turn onto Gross Dam Road.

“It is a major construction project. I don’t want to gloss over that. It will have impacts to the local community,” Lochhead said.

Denver Water staff are doing more outreach in the canyon as well, Lochhead said.

“We are committed to the project and seeing it through. We’re also committed despite the opposition to working with the local community in doing this the right way,” he said…

The Gross Reservoir Expansion Project will add 77,000 total acre feet — 72,000 for Denver Water use and 5,000 for an environmental pool that provides additional water for South Boulder Creek during low-flow periods — nearly tripling reservoir capacity.

The latest scuffle with Boulder County has brought the Gross Dam expansion squarely back into public view. At a county commissioner’s meeting in March, residents criticized Denver Water on all fronts, from specific concerns about the construction itself, to broader concerns about water scarcity in the Colorado River basin…

“This project represents an effort by Denver Water … to actually grab water while they can, before federal legislation and management of the Colorado River Basin is imposed,” McDermott said.

What McDermott is referring to is a stark disconnect in the Colorado River watershed. States downstream on the river — Arizona, Nevada and California — signed a new agreement in May called the Drought Contingency Plan that keeps them from becoming more reliant on the Colorado River. It requires cutbacks to water deliveries should levels in Lake Mead, the river’s largest reservoir, continue to drop.

Meanwhile, upstream in Colorado, Wyoming, Utah and New Mexico, no such agreement was made. Those states wound up agreeing to study the feasibility of a program that would compensate farmers to stop irrigating their cropland if reservoirs dropped, with no solid way to pay for it. They agreed too to better coordinate releases from their biggest reservoirs to aid an ailing Lake Powell. While they figure out how to develop those two concepts, the Upper Basin states keep inching along on their development projects to divert more from the river.

The 1922 Colorado River Compact, the river’s foundational governing document, gives Upper Basin states the legal cover to continue developing projects like the Gross Reservoir expansion. In the compact, each basin is allocated 7.5 million acre-feet of the river’s water. Over the decades the rapidly growing and intensely farmed Lower Basin has used much more than that. The less populated Upper Basin has never reached its full allotment. Those state have been using roughly 4.5 million acre-feet for the last 13 years, with the rest flowing downstream for the Lower Basin to use as it sees fit…

Conservation programs tend to be less expensive than massive new projects, [Doug] Kenney said. But additional water supplies stored in reservoirs give more security and reliability. It’s why water leaders push for them, even when the economics don’t make sense.

Denver Water’s collection system via the USACE EIS

Upper #ColoradoRiver Basin #drought contingency plan depends on rights holders bypassing water #COriver #aridification

The looming possibility of mandatory curtailment of water use has raised concerns among Western Slope water managers, who feel that such cuts could harm Western Slope agricultural, such as this hay filed in the Yampa River basin. However, as water levels continue to drop to record lows in Lake Powell, mandatory curltailments are being discussed as a real possibility, especially by Front Range water managers. Photo credit: Brent Gardner-Smith/Aspen Journalism

From The Steamboat Pilot & Today (Eleanor C. Hassenbeck):

The collective group of [recently signed] agreements is called the Colorado River Drought Contingency Plan.

It aims to raise the unprecedented low water levels in the largest reservoirs on the Colorado River system, Lake Powell and Lake Mead, to enable them to continue to deliver water and produce hydropower.

In Colorado, it calls for three possible actions:

  • Creating a bank of stored water in federally owned reservoirs upstream of Lake Powell. This water would be released into Lake Powell in order to make sure Colorado continues to meet obligations to deliver a certain amount of water to downstream states under the Colorado River Compact.
  • Increasing cloud seeding and removing deep-rooted, invasive plants that take up a lot of water, such as tamarisk.
  • Creating a voluntary program that would temporarily pay agricultural water users to fallow their land and send water they have a right to downstream. This is called demand management.
  • Of the options on the table, demand management — the option that would pay farmers not to use their water — is the one most likely to impact Routt County…

    Demand management is still only a hypothetical, so the Yampa River Basin could opt out of a program if it doesn’t work for the area.

    The Colorado Water Conservation Board has assembled workgroups on topics related to demand management. These groups are now meeting behind closed doors to develop preliminary reports outlining how the program might work.

    Brown said once these reports are completed and released to the public, there will be opportunities for community members to provide input on the idea. She said there will be the “opportunity for a real, thoughtful conversation, especially in the Yampa and White (river) basins.”