FromThe Cortez Journal (Jim Mimiaga) via The Durango Herald:
A 10-day whitewater boating release is planned for the Dolores River below McPhee dam and reservoir, managers said this week.
The recreational water flows will be let out from Tuesday to May 30 and are scheduled to accommodate boaters over Memorial Day weekend.
“Timing the release early for the three-day holiday was a big interest for the boating community,” said Mike Preston, general manager for the Dolores Water Conservancy District.
Beginning Tuesday, the managed “spill” will increase at a rate of 400 cubic feet per second per day to achieve a 1,200 cfs flow by the morning of May 24. The high flow will be maintained through May 27, then ramp down to 800 cfs through noon May 30. A gradual ramp down over a few days will follow.
However, the managed release is expected to continue after May 30, but to what extent has not yet been determined, water officials said.
Winter snowpack that reached 140% of normal is enough to fill McPhee Reservoir and provide the boating release below the dam. Recent cooler and rainy weather in Southwest Colorado has slowed the snowpack runoff, creating uncertainty about the final timing…
The inflow rate will depend on hard-to-predict temperatures and potential rain in the coming weeks. McPhee is expected to reach full capacity by mid-June, said district engineer Ken Curtis, and all irrigators will get a full supply for the season…
The 97-mile stretch of the Dolores River below the dam from Bradfield Bridge to Bedrock is revered by boaters for its challenging rapids and remote, red-rock canyon wilderness.
The three- to five-day Slick Rock-to-Bedrock section through winding Slick Rock Canyon offers a pristine river running experience. The 18-mile, one-day Ponderosa Gorge has convenient access and fills with locals and tourists when the river runs. No permit is required to boat the Dolores River.
The expert Snaggletooth Rapid is especially notorious for drenching boaters and occasionally flipping boats. A road along the river accessed from Dove Creek is a popular spot to spend the day watching boaters negotiate the wild hydraulics created by the rapid’s “fangs.”
Also this week, temperature suppression flows of 100 cfs were released from the dam to benefit the downstream native fishery. The strategy is to delay the spawning of the bluehead and flannelmouth suckers and roundtail chub until after the whitewater release.
Ruedi Reservoir on Friday was just under 63 percent full as it continues to recover from the recent drought, but the wet, cool spring — more snow and rain is possible today — means there is plenty of snow remaining in the upper Fryingpan River Valley.
Gauges at and near the reservoir show winter is loosening its grip, albeit slowly. The Ivanhoe Snotel site, which sits at 10,400 feet, had a snowpack Friday that is 185 percent of normal for the day, while the Kiln site (9,600 feet) stood at 161 percent of average.
That simply means more snow is locked in at high elevations than normal for this time of the year, said John Currier, chief engineer with the Colorado River District.
“This year the snow is melting out a little later higher up,” he said. “I do expect water to be fairly high for the reservoir.”
Currier predicted Bureau of Reclamation officials, who control releases from Ruedi, to keep flows in the Fryingpan at around 300 cubic feet per second (CFS) for most of the summer. That level, which will increase drastically as snowmelt increases and fills the tub, is preferable for “fisherman wade-ability reasons,” he said. “They are typically going to have to bypass [that CFS rate] because there’s much, much more water during runoff.”
Ruedi being roughly three-quarters full in mid-May is somewhat below normal, said Mark Fuller, who recently retired after nearly four decades as director of the Ruedi Water and Power Authority. That’s a sign of both a stubborn snowpack and the reclamation bureau “trying to leave plenty of room for late runoff in anticipation of a flood out of the upper Fryingpan when it gets warm,” he said…
Releases from Ruedi may make fishing the gold-medal waters below the reservoir a bit more difficult when they occur, but greatly aid the river environment in the long term, said Scott Montrose, a guide with Frying Pan Anglers.
Fish kills in the North Fork of the South Platte River are occurring during low water flow periods that fail to dilute the toxicity of heavy metals such as iron, copper and aluminum. Contaminants in the form of heavy metals move downstream, originating primarily from Hall Valley and Geneva Creek mining operations.
When water flow is adequate, there is enough oxygen to negate the impact of the toxins. When water levels are inadequate, fish develop coatings on their gills as a natural self-defense mechanism to the toxins. That protective coating ultimately renders their gills inoperable.
When and why do water levels get too low?
Water flow in the river is dependent upon how much water is released from Dillon Reservoir through Roberts Tunnel, and those decisions are made almost exclusively by Denver Water.
When more water is needed within Denver Water service areas, the rate of the water passing through Roberts Tunnel is set to flow more freely. When water is not needed to serve the Denver Water service area, the flow from Roberts Tunnel is restricted, much to the detriment of the people, and the fish, in Park County.
Water flows can be naturally low in the river during certain seasons. This year, in mid-March, for example, snowmelt had not yet occurred and the river was in its customary state of low flow prior to the fast-approaching late-spring thaw.
An abundance of area-wide spring moisture, however, created a situation where Denver Water service areas enjoyed a surplus of water. Therefore, the flow from Roberts Tunnel and Dillon Reservoir was ceased on March 11 and remained so at least until this writing.
The predictable result was the most recent fish kill, which occurred March 11-15, because flows were simply not sufficient to combat ever-present toxic heavy metals related to mining. No information has been provided by Denver Water as to when the tunnel will be reopened.
Denver Water states its position
When The Flume recently requested a statement from Denver Water regarding flows in the river and operations of Roberts Tunnel, a response was received in timely fashion.
In direct response to whether or not Denver Water felt a moral obligation to residents in Park County related to ecological systems they have long controlled, and whether Denver Water should accept responsibility for maintaining minimal flow in the South Platte River for the environmental and economical benefit of the entire North Fork region, the following statement was submitted:
“We (Denver Water) understand the potential for impacts to the fishery when flows from the Roberts Tunnel are shut down, and certainly recognize and appreciate the effect on the angling community and local businesses and outfitters. Unfortunately, operation of the Roberts Tunnel is directed by legal obligations and decrees tied to Colorado water law and binding agreements with West Slope communities where the water from the tunnel originates.
“As you know, the flows from the Roberts Tunnel originate in water diverted from West Slope rivers and streams into Dillon Reservoir. Denver Water depends on this supply when snow pack within the Upper South Platte watershed is insufficient. However, since early March, portions of the Upper South Platte watershed have received more than four feet of snow and spring precipitation continues to be strong.
“Legally, water supplied through the Roberts Tunnel can only be accessed when water is needed in Denver Water’s service area. Further, any other uses for the water, including augmenting stream flows for aquatic life or recreation uses, are not allowed as a primary purpose for operating the tunnel.
“While we provide projections about how long Denver Water will deliver water through the tunnel, those are only estimates based on snow pack, reservoir storage and other system elements. Those projections can change as conditions change; as they did in late winter and early spring this year.”
Releases from the Aspinall Unit will be increased by 250 cfs on Wednesday, May 1st. This will bring flows in the Gunnison River through the Black Canyon up to shoulder flow levels, as described in the decree for the Black Canyon water right. The current forecast for the April-July runoff volume for Blue Mesa Reservoir is 860,000 AF of inflow, which is 127% of average. Flows in the lower Gunnison River are currently above the baseflow target of 1050 cfs. River flows are expected to stay above the baseflow target for the foreseeable future.
Pursuant to the Aspinall Unit Operations Record of Decision (ROD), the baseflow target in the lower Gunnison River, as measured at the Whitewater gage, is 1050 cfs for April and May.
Currently, diversions into the Gunnison Tunnel are 675 cfs and flows in the Gunnison River through the Black Canyon are around 575 cfs. After this release change Gunnison Tunnel diversions will still be 675 cfs and flows in the Gunnison River through the Black Canyon will be around 825 cfs. Current flow information is obtained from provisional data that may undergo revision subsequent to review.
Warming temperatures but especially so during spring months
In Pennsylvania, the groundhog known as Punxsutawney Phil saw no shadow this year. That is supposed to portend an early spring.
In the Rocky Mountains, early springs have been coming no matter what. This was a cold winter in many places, but on average the climate has been warming for several decades. It’s sure to get much warmer yet.
A case in point is Colorado’s North Park, headwaters of the North Platte River but a short distance from the headwaters of the Colorado River and also the Steamboat ski area.
There, according to Dr. J.J. Shinker, an associate professor from the University of Wyoming, the temperature overall has increased 1.44 degrees Celsius (2.6 degrees Fahrenheit) since 1909.
But warming during the spring months of March, April, and May has been disproportionate, rising almost 4 degrees Fahrenheit (2.21 degrees C) on average since 1909.
“That’s a lot of warming in a short period of time,” she told members of the Colorado Water Congress at a recent conference. She also pointed out that warming at high elevations has been disproportionately greater than the global average.
(But Jeff Lukas of Western Water Assessment, the lead author of “Climate Change in Colorado,” the 2014 synthesis report sponsored by the Colorado Water Conservation Board, points out that “there is no robust and consistent evidence that higher-elevation regions in Colorado are warming at a different rate than lower-elevation regions.”
But of disproportionate warming during spring, there is no dissent. And that produces earlier runoff in the North Platte and other rivers in Colorado. On average, runoff occurs five days earlier for every degree Celsius in warming.
This matters to water managers, who try to ensure the irrigation ditches still have enough water come August and September. It also matters to mountain resorts as warming springs shrink the backend of ski season.
But everybody should be concerned for two more reasons, says Shinker. First, the worst droughts we’ve seen, the worst on record since Eurosettlement about 150 years ago, don’t come close in depth and intensity to those of the past. Forest fires of the past were also giant affairs.
This was part of natural variability. But now there is the overlay of what might be called unnatural variability, this overlay caused by human forcing of the climate.
“The warming that we are seeing is occurring at a rate that is outside the range of natural variability,” Shinker said in an interview after her talk to Colorado water managers. “And it’s occurring as a result of the greenhouse gases that result from human activity.”
Paleoclimatologists can tell much about shifting climates of the past 12,000 years by studying high mountain lakes. Consider Emerald Lake, which is in Colorado’s Sawatch Range, near the trailheads to the state’s two highest mountains, Elbert and Massive. Scientists studying lake sediments and other clues have documented shorelines that a millennium ago were much lower. The droughts then lasted for decades, even hundreds of years, what are called megadroughts.
Lake of the Woods, which is located in Wyoming along the Continental Divide south of Jackson Hole, also offers evidence deciphered by scientists of a megadrought 5,200 years ago.
The point, said Shinker, is that natural variability has always occurred in the interior West. So, too have, extreme events, such as the wildfires that accompanied a megadrought in North Park about 2,000 years ago.
In the Colorado River Basin, scientists have reached much the same conclusion. Undeniably, there have been several hard drought years since 2000. But Brad Udall of Colorado State University and other scientists have concluded that it’s not a drought as conventionally understood. Rather, rising temperatures have begun causing more evaporation and transpiration, resulting in less water getting downstream.
That doesn’t mean conventional climatic forces don’t have swagger. From her post in Wyoming, Shinker studies what causes natural climatic variability in the interior West, such as movement of the polar jet stream north and south. But now there’s an overlay to those natural climatic variations, one created by human activities.
The April 1 forecast for the April – July unregulated inflow volume to Blue Mesa Reservoir is 925,000 acre-feet. This is 137% of the 30 year average. Snowpack in the upper Gunnison River basin is currently 132% of average. Blue Mesa Reservoir current content is 259,000 acre-feet which is 31% of full. Current elevation is 7440 feet. Maximum content at Blue Mesa Reservoir is 829,500 acre-feet at an elevation of 7519.4 feet.
Black Canyon Water Right
The peak flow and shoulder flow components of the Black Canyon Water Right will be determined by the May 1 forecast of the April – July unregulated inflow volume to Blue Mesa Reservoir. If the May 1 forecast is equal to the current forecast of 925,000 acre-feet of runoff volume, the peak flow target will be 6,513 cfs for a duration of 24 hours. The shoulder flow target will be 915 cfs, for the period between May 1 and July 25. The point of measurement of flows to satisfy the Black Canyon Water Right is at the Gunnison River below Gunnison Tunnel streamgage at the upstream boundary of Black Canyon of the Gunnison National Park.
Aspinall Unit Operations ROD
Pursuant to the Aspinall Unit Operations Record of Decision (ROD), the peak flow and duration flow targets in the lower Gunnison River, as measured at the Whitewater gage, will be determined by the forecast of the April – July unregulated inflow volume to Blue Mesa Reservoir and the hydrologic year type. At the time of the spring operation, if the forecast is equal to the current forecast of 925,000 acre-feet of runoff volume, the hydrologic year type will be set as Moderately Wet. Under a Moderately Wet year the peak flow target will be 14,350 cfs and the duration target at this flow will be 10 days. The duration target for the half-bankfull flow of 8,070 cfs will be 20 days. The criteria have been met for the drought rule that allows half-bankfull flows to be reduced from 40 days to 20 days.
Projected Spring Operations
During spring operations, releases from the Aspinall Unit will be made in an attempt to match the peak flow of the North Fork of the Gunnison River to maximize the potential of meeting the desired peak at the Whitewater gage, while simultaneously meeting the Black Canyon Water Right peak flow amount. The magnitude of release necessary to meet the desired peak at the Whitewater gage will be dependent on the flow contribution from the North Fork of the Gunnison River and other tributaries downstream from the Aspinall Unit. Current projections for spring peak operations show that flows in the Gunnison River through the Black Canyon could be over 7,500 cfs for 10 days in order to achieve the desired peak flow and duration at Whitewater. With this runoff forecast and corresponding downstream targets, Blue Mesa Reservoir is currently projected to fill to an elevation of around 7500 feet with an approximate peak content of 660,000 acre-feet.
To save endangered fish and support healthy water levels, conservationists get creative on the Colorado River’s 15-Mile Reach
The Colorado River—that ancient and mighty flow that has carved the landscape of the American West over millennia—serves as a primary water source for approximately 40 million people. But there is a stretch in the headwaters that at times runs so low and weak it has trouble sustaining some of its oldest inhabitants.
This stretch, known as the 15-Mile Reach, is home to four federally endangered fish species–the Colorado Pikeminnow, Humpback Chub, Bonytail and Razorback Sucker. In the springtime, when irrigation diversions begin but snowpack runoff is still nominal, the 15-Mile Reach can drop to dangerously low levels.
Now, a groundbreaking deal between Walton Family Foundation grantee the Colorado Water Trust, the Orchard Mesa Irrigation District, Grand Valley Water Users Association and the U.S. Bureau of Reclamation, which manages water and power in the West, have secured a legal mechanism to be able to send more water down the river at critical times through a creative arrangement that both enhances environmental and recreational flows and protects existing water rights.
The deal provides habitat protection for these embattled fish species by bringing more water into the Reach when it is needed.
This mechanism allows water to be protected from the point of conservation all the way down and through any excess capacity at the Grand Valley Power Plant, then provides instream flow benefits down and through the 15-Mile Reach.
The agreement, like many involving water in the West, required resourceful thinking among all participants. That’s because under current state law, there aren’t many options for upstream water rights owners to send some of their water downstream for the benefit of conservation without going through an often protracted water court process.
And some might question whether using a water right, even for this kind of worthy cause, meets the “beneficial use” standard required by law.
Faced with that hurdle, the partners needed to find another path forward that met that strict legal requirement. They found their solution just north of the Reach in the aging Grand Valley hydro-electric facility.
Built in 1933, the plant is now undergoing a substantial renovation with help from the Colorado Water Trust.
The Trust was able to lease excess capacity in the hydropower plant, and the Orchard Mesa Irrigation District used these proceeds from this lease to help pay for some of the renovations. This kind of creative win-win solution is a model for how we manage the river in the future.
By bringing clean power into the equation, the deal operates under the umbrella of existing law to give water rights owners the flexibility and go-ahead to support a healthy and sustainable river ecosystem.
“The agreement sends water to a critical reach of the river without requiring a permanent change to those water rights,” explains Anne Castle, a Colorado water lawyer and former assistant secretary for water and science at the U.S. Interior Department.
Anne helped broker the groundbreaking deal.
“This arrangement could set a precedent moving forward,” Anne says, “and it also proves that there is a way for those with water supplies to be able to send water downstream in a voluntary, compensated and temporary manner.”
The final agreement is an innovative “three-fer” that provides multiple benefits.
First, the water is protected for instream flow benefits from the original point of use down to the hydropower plant. Then, the water’s momentum is harnessed by the plant and converted to clean energy. Finally, the water continues downstream, augmenting the 15-Mile Reach and helping the river flow at healthier levels, which benefits the fish.
Water is scarce in the West. Securing the necessary federal, state and local approvals can require a great deal of coordination—and more than a little ingenuity. This is precisely why this nimble approach is such a landmark achievement.
As the health of the Colorado River Basin reaches a critical inflection point, with demand for water now exceeding supply, more agile, innovative projects like what is being accomplished for the 15-Mile Reach offer a new vision for a water-strapped West.
Complex problems often require innovative solutions. As growing populations continue to rely on the 1,500 miles of the Colorado River, this victory proves that progress is possible—often one mile at a time.
Ted Kowalski: Colorado River Initiative Lead and Senior Program Officer
Ted is a senior program officer, leading the Walton Family Foundation’s Colorado River initiative.