Rains cause Lake Granby to spill again | SkyHiNews.com

Rains cause Lake Granby to spill again

After a long week of wet weather, Lake Granby is spilling once more. Steady rain on both sides of the divide has filled Front Range reservoirs, limiting the amount of water being diverted through the Alva B. Adams Tunnel. As of Wednesday evening, July 30, Shadow Mountain Dam was releasing about 550 cubic feet per second, said Kara Lamb with the U.S. Bureau of Reclamation. Granby Dam was also releasing around 550 cfs. Releases from Granby Dam were primarily through the river gate, though some water is coming over the spillway. On the other side of the divide, officials expect outflows from Olympus Dam into the Big Thompson River to increase. Inflows to Lake Estes in Estes Park are being returned to the Big Thompson River via the Big Thompson Power Plant.

Agencies brace for ‘robust’ runoff in Grand County

Water operators, county and town officials have started planning for this year’s high water season. If this spring is anything like last year when the high country experienced consecutive hot days during peak runoff, there’s a chance of flooding, officials say. Snowpack in the Upper Colorado River Basin contains 142 percent of the average water content for this time of year, meaning it’s a “pretty robust year” for snowpack, said Northern Colorado Water Conservancy District spokesperson Dana Strongin. In fact, in an April 5 “Runoff Update,” Northern blogged: “Some of us are using words like ‘epic’ to describe the West Slope snowpack.” The Grand County Office of Emergency Management has held its first meeting with town managers and public works directors to talk about planning for high water levels and coordinating with dam operators. The towns and county are organizing a program to make sandbags available at a discounted rate, said Trevor Denney, Grand County’s Emergency Manager. If stream levels start to rise quickly, alerts will be sent to people in low-lying areas along streams, Denney said. Notifications will be made through Reverse 911 and the cell phone system Code Red. (For those not signed up with the local Code Red notification system, visit http://www.gcemergency.com, or call 970-887-2732.) From the unexpected flooding that took place last year, areas of special concern are along the Fraser River, such as by the Hi Country Haus and Beaver’s Village Lodge in Winter Park and near housing complexes in Granby, along the Colorado River between Lake Granby and Windy Gap, and along the North Inlet in the town of Grand Lake. The Fraser River Basin is at about 136 percent of average for snowpack water content. Of priority will be watching for dead-fallen trees and other large debris that can get swept downstream and caught under bridges or culverts, blocking water flows, Denney said. The Northern Colorado Water Conservancy District is planning controlled releases out of Granby Dam in its preparation for the runoff season. As of Wednesday, April 6, Granby Dam elevation sat at 22 feet from full. Willow Creek snowpack is at 150 percent of average. Beginning April 6, releases from Granby Dam into the Colorado River increased by 60 cfs. Another increase brought the flow below the dam to 140 cfs. Another change on Friday is planned to bring the flow to about 200 cfs through the weekend. Northern is also making changes at Willow Creek Dam. Flows in Willow Creek below the dam could be as high as 350 cfs. The early controlled releases before dams reach capacity should help avoid major peaks in rivers, Strongin said. Whether the Granby Dam reaches the point of the spillway will depend on weather and water levels, she said. The last time the Granby Dam spilled was in 2000. Last year, Northern narrowly averted a spill by conducting releases. “We’re trying to avoid a flood in that area,” Strongin said. Although peak runoff is impossible to predict since it greatly depends on spring weather temperatures in the area, last year’s runoff peaked the first week of June due to consecutive 80-degree days that hastened the pace of high-elevation melting snow. – Tonya Bina can be reached at 970-887-3334 ext. 19603.

Lake Granby spill ends

Water that began to spill over the Granby Dam spillway at Lake Granby on Wednesday, July 16, is now headed instead toward the Front Range through the Alva B. Adams Tunnel. The lake officially started spilling last Wednesday, according to Northern Colorado Water Conservancy District, when the water level reached 8,279.5 feet. Kara Lamb with the U.S. Bureau of Reclamation wrote in an email late Tuesday night, July 22, that the spill had ended and diversions to the Front Range through the tunnel increased to 408 cubic feet per second. Meanwhile, she wrote, releases from the dam into the Colorado River are running at about 70 cfs.

Lake Granby releases increased again

Northern Water Conservancy District and the U.S. Bureau of Reclamation increased releases out of Lake Granby from 2,150 cubic feet per second to 2,400 cfs on Friday, June 12. The increased flows are expected to fill the Colorado River below Granby Dam to bank-full capacity, according to officials with Northern Water. When the releases from the lake reached about 1,800 cfs, in conjunction with high flows in the Fraser River, the Colorado River near Hot Sulphur Springs was causing minor in the town campground. About two weeks ago, releases from the lake were being made in coordination with releases elsewhere on the Upper Colorado River to help endangered fish near Grand Junction. Those releases were scheduled to end on June 10. The new, higher releases from Lake Granby are intended to make room to accommodate continued high inflows as area snowpack melts. The Lake Granby pool elevation is increasing an average of 3 inches per day despite the releases, according to Northern Water. According to Bureau of Reclamation data, Lake Granby was 96.5 percent full at an elevation of 8,277.5 feet as of Friday afternoon. The dam begins to spill on its own when the lake elevation exceeds 8,280 feet. Visit http://www.usbr.gov/gp-bin/arcweb_graresco.pl for the latest conditions at Lake Granby.

State of the Colorado River: An unusual year for snowpack, runoff

It's been a fickle season for snowpack, and runoff could go either way in this unusual water year. That was the message delivered by regional water managers at the Colorado River District's State of the River meeting on Tuesday evening, May 26, in Granby. During the meeting, officials from the Upper Colorado River Basin's biggest water interests including Northern Water, Denver Water and the U.S. Bureau of Reclamation spoke about some of the basin's biggest issues, including the state of runoff and snowpack in the region and the movement at Ritschard Dam on Wolford Mountain Reservoir. Though snowpack seemed to falter during what proved to be a rather dry March, it's been building steadily over the last three to four weeks, explained Don Meyer with the Colorado River District. The variations in snowpack have pushed the basin into "uncharted territory," he said. "I think the message here is think 2010 in terms of snowpack," Meyer said. Though he added that snowpack is not analogous to runoff, Meyer said 2015 "will likely eclipse 2010 in terms of stream flow." Victor Lee with the U.S. Bureau of Reclamation echoed Meyer, adding that recent cold temperatures across the region have allowed snowpack to persist. Though snowpack is currently below average, it could linger past the point at which the average snowpack tends to drop. However, everything is still up in the air, Lee said. "I just want to stress that there's a lot of uncertainty with the snowpack," he said. If the current snowpack does translate into high runoff in Grand County, there may not be anywhere to put it, Lee said. Front Range reservoirs are full, and storage in Lake Granby is the highest it's ever been for this time of year, according to Lee's presentation. "We're way above what we've ever seen in the past," he said. The result will likely be higher flows from Lake Granby. Though it could be a good runoff year for Grand County, Meyer said that snow-water equivalent above Lake Powell is still well below average, making it a dry year for the Upper Colorado River Basin overall. Ritschard Dam Officials aren't sure when the settling and movement at Ritschard Dam will stop, but it poses no threat to safety, said John Currier with the Colorado River District. "We really are absolutely confident that we don't have an imminent safety problem with this dam," Currier said. The dam has settled around 2 feet, more than twice the anticipated depth, since 1995. Inclinometer readings from parts of the dam's core have shown one section moved around 7 inches downstream, Currier said. Problems are focused on the rock-filled shells that line either side of the dam's clay core, Currier said. Moisture control was not used during the construction of the shells, leaving them less dense than they needed to be, he said. The structural issues were discovered during routine maintenance work. As of now, there are no definitive plans on how to repair the dam, though Currier said he anticipated "some type of structural remediation." What kind of remediation or an approximate cost is currently unknown, he said. "I would like to say by this time next year we would have a very firm plan in hand of what we want to do with the remediation of this dam," Currier said. Some possibilities include removing the top of the dam and reprocessing the shell material before returning it in a more dense state, Currier said. To relieve some pressure on the dam, the district will operate Wolford Mountain Reservoir at 10 feet below full pool this year to reduce deformation, though Currier said that's not a sustainable resolution. "Our goal is to keep everybody apprised of what's going on and how it might affect you," Currier said. Endangered Fish The Bureau of Reclamation will increase flows from the Granby Dam to 1,500 CFS around May 29 and maintain those flows until around June 8, Lee said. The releases will be part of an endangered fish recovery program and will be coordinated with releases from other basin reservoirs to enhance peak flows in the Grand Valley where the plan is focused. Wolford Mountain Reservoir will also participate in the coordinated releases, Meyer said. The program hopes to re-establish bonytail chub, Colorado pikeminnow, razorback sucker and humpback chub populations to a 15-mile stretch of the Colorado River above Grand Junction. Windy Gap Firming After receiving its Record of Decision last year, the Windy Gap Firming Project's next major hurdle is acquiring a Section 404 permit from the Army Corps of Engineers for the construction of Chimney Hollow Reservoir, said Don Carlson with Northern Water. The permit regulates dredged or fill material into water as part of the Clean Water Act. Northern Water hopes to acquire the permit this year, with construction possibly beginning in 2016 or 2017, Carlson said. The project seeks to firm up the Windy Gap water right with a new Front Range reservoir. The project currently stores water in Lake Granby. Because it's a junior water right, yield for the project is little to nothing in dry years. Northern Water also hopes to establish a free-flowing channel of the Colorado River beside the Windy Gap Reservoir as part of the Windy Gap Reservoir Bypass Project. The new channel would allow for fish migration and improve aquatic habitat along the Colorado River. That project still needs $6 million of its projected $10 million cost. Moffat Tunnel Flows Moffat Tunnel flows are hovering around 15 CFS as Denver Water is getting high yield from its Boulder Creek water right, said Bob Steger with Denver Water. The increased yield from that junior water right means flows through Moffat Tunnel will remain low through early summer, Steger said. "The point is we'll be taking a lot less water than we normally do," he said. Denver Water expects its flows through the tunnel to increase in late summer as its yield from Boulder Creek drops, Steger said. Williams Fork Reservoir, which is used to fulfill Denver Water's obligations on the Western Slope, is expected to fill in three to four weeks, Steger said.

Spill, baby, spill: Lake Granby likely to flow over dam within 10 days

GRAND COUNTY – Sitting just 5 feet from full on Thursday, Lake Granby was on course to spill. The last time the lake (also known as Granby Reservoir) had water flowing down the spillway was in 2000. Such an event of greater than 75 cfs flowing at the Near Granby Gauge would be a long-awaited gift to the Colorado River between the Lake Granby Dam and Windy Gap, said Jon Ewert, DOW aquatics biologist in Hot Sulphur Springs. That section of the Colorado has been deprived of flushing flows because of the dam built for reservoir storage. “It would be beneficial to that stretch,” Ewert said, “it would move sediment out and clean out riffles (stretches of gravel where fish like to spawn and where insect production is).” “What we will do, when a spill is imminent, is max out the release from the bottom of the reservoir,” said Water Northern Conservancy District spokesperson Brian Werner. The reason for the controlled release is to avoid water going over the top of the spillway, he said. “We’ll do everything in our power to minimize that.” Northern plans to institute a call list for downstream property owners to warn them of the possible spill with increased river flows, Werner said. The Granby Reservoir spilled each year from 1995 to 2000. In each of those years there were controlled releases through the bottom of the dam with about two days of water going over the spillway, according to Werner. Spills have lasted from a couple of days to 10 days. Flows in the river from a spill can exceed 400 cfs. In 1996 and 1997, water flows at the spill exceeded 2,000 cfs. “We don’t anticipate getting anywhere near that high this year,” Werner said. With runoff peaking last week, the Northern Water Conservancy District was moving water out of Shadow Mountain Reservoir into Granby Reservoir, releasing by as much as 5,000 cfs for a period of 12 hours. In the Colorado-Big Thompson system, Shadow Mountain Reservoir helps to maintain a constant surface elevation in natural Grand Lake and is a conduit between Granby Reservoir and Grand Lake. Heightened runoff in Grand Lake inlets caused that lake to rise, which by Colorado-Big Thompson decree is not allowed to fluctuate by more than 1 foot. As far as Granby Reservoir’s chances for spilling, “We’re 99 percent sure it’s going to spill,” Werner said. The lake is rising about .5 feet per day, which means the lake could spill within about 10 days. “If at the start of the year you said we were going to spill, we would have laughed,” he continued. “It shows what can change in a water year in just a couple of months.” Pumping at Willow Creek is planned to be minimal, with one of the pumps turned off today, June 18. Northern plans to cut the other pump when “absolutely assured Granby spills,” Werner said. Northern is not sending water through the Adams Tunnel with Front Range reservoirs full. Windy Gap, which pumped 6,700 acre-feet, has pumps shut off. – Tonya Bina can be reached at 970-887-3334 ext. 19603 or e-mail tbina@skyhidailynews.com.

Ritschard Dam work pushed to 2018; expert says dam failure ‘essentially nonexistent’

An earthwork project on Ritschard Dam, north of Kremmling on Wolford Mountain Reservoir, has been postponed this summer due to a combination of factors, though officials plan to move forward with construction in 2018. Officials from the Colorado River District, which owns and operates Wolford Mountain Reservoir, announced in spring 2016 that they were scrapping plans to conduct a multimillion dollar rehabilitation project on Ritschard Dam, which when full holds back Wolford’s 66,000 acre-feet of water. At that time the district announced it would initiate an earthwork project to restore the dam to its original height after several years of settling dropped the dam’s crest by roughly one-and-a-half feet. District officials, however, announced plans this week to postpone the dam heightening project until 2018. Jim Pokrandt, spokesperson for the river district, explained the decision was based on several factors including that the project is still working through the permitting process and officials were concerned about a late start for construction and the potential for bumping up against colder weather. Pokrandt further noted that 2017 has been a very busy construction season and bids on the project would have been high. “This is still a good project and it needs to be done. It will just take another year,” Pokrandt said. The River District had previously planned to draw down Wolford to accommodate the earthwork but the recent announcement means accelerated drawdowns will not occur. According to Ray Tenney, Deputy Chief Engineer for the District, for the remainder of summer and fall, the usual and expected water deliveries for contract and endangered fish habitat purposes will occur, resulting in a typical seasonal drawdown of about 10 feet in water elevation in coming months. Wolford’s recreational amenities, including camping, boating, fishing, and day-use, will still remain open to he public. Ritschard Dam was originally built in 1995. The River District realized the dam was settling and shifting at a rate higher than initially anticipated in 2009. The district initially planned to conduct roughly $15 million in rehabilitation work but last year the district announced it would scrap the project after a team of former engineers from the Federal Bureau of Reclamation examined the dam and determined the accelerated settling did not necessarily pose a significant risk. “The odds of having a dam failure associated with ongoing movement of the dam, as a practical matter, is essentially nonexistent,” said John Currier, district chief engineer, at the 2016 State of the River meeting in Granby.

Lake Granby releases aid power plant project

Crews began work in May on the Granby Hydropower Plant at the base of Granby Dam on the Colorado River. This will be the second Colorado-Big Thompson Project hydropower plant owned and operated by Northern Water Conservancy District. The first was the Robert Trout Hydropower Plant at the outlet to Carter Lake, which began operating in May 2012. Scheduled to be complete in May 2016, the Granby Hydro Plant will generate a maximum of 5 million kilowatt hours annually. The plant's renewable power is intended to benefit customers in Grand and Jackson counties. Granby-based Mountain Parks Electric Inc. has contracted with Northern Water to purchase the power, according to Northern. In 2011, the U.S. Bureau of Reclamation granted Northern Water a Lease of Power Privilege to construct the Granby Hydro Plant. Northern Water then secured a low-interest loan from the Colorado Water Conservation Board to construct the $5.7 million facility. Lake Granby releases Before Granby Hydro Plant construction could proceed it was necessary to make releases through the reservoir's radial gates and spillway rather than via the dam's outlet works. This unusual method of releasing water from Lake Granby to accommodate the hydro plant's construction was possible this year because Lake Granby is nearly full. However, the reservoir's high water level also presents several future operational challenges, such as ice buildup on the reservoir outlet's radial gates, and creating space in Lake Granby for 2016 spring runoff. For these reasons Northern Water and Reclamation began pre-emptive operational releases from Lake Granby through the reservoir's spillway earlier this month. Although the required release rate in August is 40 cubic feet per second, Northern Water and other East Slope diverters are adding 35 cfs to that release rate to benefit endangered fish in the Colorado River. In addition, Lake Granby's operational releases are approximately 125 cfs, bringing the reservoir's current total release to 200 cfs, until further notice. Northern Water and Reclamation have been and will continue to communicate with Grand County, Trout Unlimited, and others during these operations at Lake Granby.

Fishing Corner: Rainbows still hitting at the ‘W’s

The slush is here and very bad in spots. The rainbows are hitting well at Willow Creek, Wolford and Williams Fork, there are a lot of trout along the shorelines in the deeper reservoirs. There are still a few spawning kokanee in Wolford, the younger ones are hitting down by the dam in the old river channel. Lakers in Granby and Williams Fork are biting very good on small jigs tipped with sucker meat. Bernie Keefe has been a fishing guide on lake Granby for longer than 15 years.

Exercise considers ‘worst-case scenario’ of Granby Dam failure

What if 361,000 acre feet of water, the amount that is in the reservoir today, were to breach the Granby Dam and spill into the river valley? Area emergency responders took part in a table-top exercise earlier this month to review and revise the play book of what to do if this “worst-case scenario” were to happen. “It’s important that the local, county, state, and federal agencies are working together to coordinate and be prepared in case something this unlikely does happen,” said Bureau of Reclamation spokesperson Kara Lamb. The formal exercise, conducted every three years, is part of the Safety of Dams program through the Bureau, which owns the system of dams and dikes that make up the Colorado Big Thompson Project. The table-top exercise is followed up with a functional exercise, to take place next year, during which emergency officials act out the communication in the plan. The exercise took place on Nov. 2 in Granby, focusing on Granby, Willow Creek and Shadow Mountain dams. There are no current issues with the dams, Lamb stressed, and there hasn’t been since they were constructed. Nevertheless, the exercises are part of an effort to be prepared for a wide realm of circumstances that could happen, she said. County emergency officials were treated to a scenario that, for people like Granby Mayor Ted Wang, were an eye-opener for what could happen if the Granby Dam were to break. The worst-case-scenario simulation estimated that if seepage were identified at 7 a.m., and the dam were to completely fail by midnight, the flats west of Granby would end up with 30 feet of water on the ground and Hot Sulphur springs would experience water 50 feet above ground. The water would follow the flow corridor of the Colorado River and spill out into low-lying areas, submerging the future community Orvis Shorefox and Granby’s “hotel row” as well as Hot Sulphur Springs. Mayor Wang noted at the exercise that the Orvis development at the west-end of Granby could have an estimated population of 1,800 residents. Warnings about any possible dam failure would take place before an actual break and every effort would be made to warn the communities, said Grand County Sheriff Rod Johnson. The Grand County Sheriff’s office would be in charge of coordinating the effort to get people to safety. The recent emergency practice exercises should not cause alarm, officials reiterated. Lamb encourages area residents to keep faith in the dam and its operators. Earthen dams are extremely stable because they are so thick, and it’s “very unlikely you’d see anything like this happen,” she said. With the Bureau’s 375 dams and dikes across the western United States, some more than 100 years old, the Bureau has had one failure. On June 5, 1976, the Teton Dam in Idaho, designed by the U.S. Bureau of Reclamation, failed just as it was being completed and filled for the first time. The collapse resulted in the death of 11 people and 13,000 head of cattle, and total damage estimates have ranged up to $2 billion. The dam was never rebuilt. “Because of that, the whole Safety of Dams was created,” Lamb said. The program is funded separately from the agency due to its importance; that way, budget cutbacks cannot affect it, she said. At full capacity, the Granby Reservoir can hold 540,000 acre-feet of water, which puts water elevation at 8,280 feet. On this November day, the water sits at an elevation of 8,253 feet. -Tonya Bina can be reached at 887-3334 ext 19603 or e-mail tbina@grandcountynews.com.