The spring peak operation is nearing completion. The peak release period of the spring peak operation has concluded. Flows at the Whitewater gage were over 14,350 cfs for six days and a peak daily flow of 16,500 cfs occurred on June 9th.
The ramp down period has begun and releases will continue to be decreased through Thursday, June 20th. The ramp down schedule is shown below. Daily flows for the Gunnison River below the Gunnison Tunnel should be considered as approximations. Actual flows may vary from the numbers below if side inflows to Crystal Reservoir increase or decrease the spill rate beyond what is currently forecast.
This is quite a series of video from the USBR and Awesome Science detailing the problems in 1983 at Glen Canyon Dam after first fill of Lake Powell and the destruction in the left spillway. They also show the reconstruction of the spillways and testing afterward. They’ll likely never be used again.
Those who keep an eye on the lower Fryingpan River, below Ruedi Reservoir, may have noticed that the river’s flow increased this week in three distinct steps.
On Monday, the river was flowing steadily at just about 200 cubic feet per second.
On Tuesday, it stepped up to 250 cfs, and on Thursday, it took another 50 cfs jump, to 300 cfs.
And on Friday, the river jumped another 25 cfs, heading into the weekend flowing at about 325 cfs. (See USGS gage).
The increases in flow were directed by Tim Miller, a U.S. Bureau of Reclamation hydrologist who manages water levels in Ruedi and also manages water releases from the reservoir, which is about 14 miles above Basalt.
The water from the reservoir was being released through the dam’s outlet structures, as well as through the hydropower plant at the base the dam, into an area that’s popular with anglers, and large fish, and nicknamed the “Toilet Bowl,” due to its swirling waters.
Miller’s goal is to fill the reservoir by July 4, while avoiding overfilling the reservoir, which would cause water to flow over the dam’s spillway, which does not have a flow-controlling gate, as some spillways do.
Miller is now balancing some factors beyond his control: the deep snowpack above Ruedi, lingering cold temperatures and varying flow levels in the transmountain diversions tunnels in the upper Fryingpan Basin.
On Friday, Ruedi was 64.6 percent full and holding 66,116 acre-feet of water, according to Reclamation. When full, the reservoir holds 102,373 acre-feet.
But, given the deep snowpack above Ruedi, Miller said “it’s very possible” the reservoir could spill, something that, to his knowledge, has only happened a few times since the reservoir and dam were completed in 1968.
The Ivanhoe snow-telemetry, or SnoTel, site above Ruedi, in the Ivanhoe Creek subbasin, is at 10,400 feet. The site shows there was still 54 inches of snow at that elevation Friday. That’s up from 42 inches a week ago but still below the March 14 peak of 90 inches.
“It just really depends on the weather,” Miller said of future releases into and out of Ruedi.
Peak runoff in the upper Colorado River basin within Colorado is now expected to arrive late, between June 15 and June 25, as more cool weather is in the forecast.
Not for flood control
Victor Lee, also a hydrologist with the Bureau of Reclamation, made a presentation on Ruedi and Green Mountain reservoirs Monday at the Colorado River Basin roundtable in Glenwood Springs.
He said he expected, because of the snowpack, to see above-average releases out of Ruedi as the reservoir fills and to see above-average diversions through the Boustead Tunnel, which sends water collected by the Fryingpan Arkansas Project diversion system under the Continental Divide to Turquoise Lake, near Leadville.
Since 1972, the Fry-Ark Project has diverted an average of 54,000 acre-feet a year through the Boustead Tunnel, but it’s expected to divert 84,000 acre-feet this year, according to Lee.
On Friday, the tunnel was sending east a relatively modest 38 cfs of water, but it had been sending about 300 cfs on May 17.
Lee also sounded a cautionary note about the rare prospect of Ruedi filling, spilling and sending at least 600 cfs of water down the lower Fryingpan.
“I have to stress that Ruedi is not a flood-control project, and if we get filled, there are no gates on the spillway to stop water from going,” Lee said. “And so, if we’re full, and we fill before peak runoff, there is always that chance that we would have excess flows beyond 600 cfs.”
Aspen Journalism covers rivers and water in collaboration with The Aspen Times. The Times published a version of this story on Saturday, May 25, 2019.
The May 15th forecast for the April – July unregulated inflow volume to Blue Mesa Reservoir is 990,000 acre-feet. This is 147% of the 30 year average. Snowpack in the Upper Gunnison Basin peaked at 143% of average. Blue Mesa Reservoir current content is 457,000 acre-feet which is 55% of full. Current elevation is 7473.2 ft. Maximum content at Blue Mesa Reservoir is 829,500 acre-feet at an elevation of 7519.4 ft.
Based on the May forecasts, the Black Canyon Water Right and Aspinall Unit ROD peak flow targets are listed below:
Black Canyon Water Right
The peak flow target is equal to 7,158 cfs for a duration of 24 hours.
The shoulder flow target is 966 cfs, for the period between May 1 and July 25.
Aspinall Unit Operations ROD
The year type is currently classified as Moderately Wet.
The peak flow target will be 14,350 cfs and the duration target at this flow will be 10 days.
The half bankfull target will be 8,070 cfs and the duration target at this flow 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.)
Pursuant to the Aspinall Unit Operations ROD, 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 latest forecast for flows on the North Fork of the Gunnison River keeps river flows below their projected peak flow level for most of the 10 day forecast period. Warmer weather and higher flows are forecast to return by the first days of June.
Therefore ramp up for the spring peak operation will begin on Wednesday, May 22nd, with the intent of timing releases with this potential higher flow period on the North Fork of the Gunnison River. Releases from Crystal Dam will be ramped up according to the guidelines specified in the EIS, with 2 release changes per day, until Crystal begins to spill. The release schedule for Crystal Dam is:
Crystal Dam will be at full powerplant and bypass release on May 26th. Crystal Reservoir will begin spilling by May 27th and the peak release from Crystal Dam should be reached on May 30th or 31st. The flows in the Gunnison River after that date will be dependent on the timing of the spill and the level of tributary flow contribution. Estimates of those numbers will be determined in the upcoming days.
The current projection for spring peak operations shows flows in the Gunnison River through the Black Canyon between 7,000 cfs and 8,000 cfs for 10 days in order to achieve the desired peak flow and duration at Whitewater. Actual flows will be dependent on the downstream contribution of the North Fork of the Gunnison River and other tributaries. Higher tributary flows will lead to lower releases from the Aspinall Unit and vice versa.
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.
Here’s the release from the Southeastern Colorado Water Conservancy District (Chris Woodka):
Agriculture received the lion’s share of water from the Fryingpan-Arkansas Project this year, when an abundant water supply is expected to boost Arkansas River flows as well as imported water.
Allocations totaling 63,000 acre-feet were made by the Southeastern Colorado Water Conservancy District board on Thursday (May 16), with 48,668 acre-feet going to agriculture, and 14,332 going to cities. The district is the agency responsible for management of the Fry-Ark Project, which is operated by the U.S. Bureau of Reclamation.
“This is a remarkable outcome for the Arkansas River basin, given the dry conditions we faced last year,” said Garrett Markus, water resources engineer for the district. “The conditions look favorable during the next three months, when rainfall should add to the abundant snowpack already in the mountains.”
Water users in nine counties benefit from the supplemental water provided by the Fry-Ark Project, ranging from large cities in Pueblo and El Paso counties to irrigation companies in the Lower Arkansas Valley. Fry-Ark Project water accounts for about 10 percent of flows in the Arkansas River annually.
While cities are entitled to more than 54 percent of project water, their accounts in Pueblo Reservoir are relatively full, freeing up additional water for agriculture. Municipal allocations include:
Fountain Valley Authority, 7,353 acre-feet;
Pueblo Water, 2,000 acre-feet;
Cities west of Pueblo, 2,312 acre-feet;
Cities east of Pueblo, 2,667 acre-feet.
In the event of changing conditions – a reduction of precipitation or rapid melt-off of snow – the District initially will release only 28,256 acre-feet of water to irrigation companies until final imports are certain, with the remainder delivered as soon as the expected total is reached. Municipal allocations would not be affected by a shortfall, because they are all below allocation limits.
Another 17,338 acre-feet of irrigation return flows were allocation, and 10,016 acre-feet will be initially released.
Reclamation estimates the project will yield 84,000 acre-feet this year, but deductions from that total are made for evaporation, transit loss and obligations to other water users reduce the amount of water available to allocate.
The Fry-Ark Project imports an average of about 56,000 acre-feet through its collection system in the Fryingpan River and Hunter Creek watersheds above Basalt. Water comes through the Boustead Tunnel into Turquoise Lake, through the Mount Elbert Power Plant at Twin Lakes and into terminal storage at Pueblo Reservoir.
Three-month projections from the National Oceanic and Atmospheric Administration predict cooler and wetter than average conditions for eastern Colorado.
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.
Boustead Tunnel Construction via The Aspen Times
The end of the tunnel that brings water from Hunter Creek to the Fryingpan River drainage, and then on to the eastern slope. Photo credit: Brent Gardner-Smith, Aspen Journalism.
A portion of the flow in Hunter Creek is diverted to the Front Range and to locations downvalley from Aspen.
“The Colorado River runs right right behind our backyard on the (border) of our reservation if you look at the map,” said [Damon] Clarke in an interview. “And we don’t get a drop from it. You guys, down there in the Valley, you get tons and tons of water from the river.”
If a water rights settlement became law, the Hualapai Tribe would get 4,000 acre-feet of Colorado River water each year…
The current bills, introduced in both the U.S. House and Senate, include:
$134.5 million to construct a pipeline bringing most of that water to the reservation, which includes the community of Peach Springs and Grand Canyon West, the tribe’s tourist hotspot;
$32 million for operations, maintenance and repairs once the tribe assumes title over the pipeline;
$5 million for the Department of Interior to operate it before that time;
$2 million for DOI to provide technical assistance to the Hualapai Tribe.
But Interior is still against the specific terms of the settlement.
During testimony in late 2017, Alan Mikkelsen, who was then the deputy commissioner of the Bureau of Reclamation, told the Senate Indian Affairs Committee that while the Department of Interior generally supports settlements for Indian water rights, “we believe the cost to construct a 70-mile pipeline from the Colorado River lifting water over 4,000 feet in elevation will greatly exceed the costs currently contemplated.” In his testimony, Mikkelsen also worried about litigation.
Mikkelsen is now senior adviser to DOI Secretary David Bernhardt. Interior declined an interview, but a spokeswoman said via email that the department’s position on the Hualapai water settlement remains the same.
Rep. Tom O’Halleran (D-AZ01), the lead sponsor of the settlement legislation in the House, said the only sticking point is the dollar amount.