by Marissa Lorenz
Grand County and its water partners reacted quickly this week to early-season concerns for aquatic habitat when monitoring systems showed continued low river flows partnered with high water temperatures.
On Friday, the US Geological Survey’s Colorado River gage near Kremmling reported a low river flow of barely 300 cfs (cubic feet per second) and a temperature that peaked at 71 degrees Fahrenheit.
With 58 years of data collected at the site, the historic mean for flow this time of year–when runoff is normally increasing and/or nearing its peak–is around 1750 cfs. Warm river temperatures at any time of the year are considered dangerous for the fishery.
According to the Colorado River Headwaters Chapter of Trout Unlimited, “Warm water holds less oxygen, and trout have trouble getting enough oxygen in water over 65 degrees. They can suffocate when water temps get into the 70s. Playing, catching, and releasing
a fish in warm water is often a death sentence for that fish.”
In response to the concerning measurements, reported Grand County Manager Ed Moyer, the Colorado River Water Conservation District (CRWCD) sent an email to Grand County and their other Learning by Doing partners, Northern Water, and Denver Water, including a call to action.
The CRWCD asked each water management entity to allow for additional bypass flows from their various diversion projects that would permit “extra” water to continue naturally downstream, increasing river flow and addressing high temperatures on the Colorado River at and below Kremmling.
By the end of the day, stated Moyer, all three organizations had responded by “bypassing” water flow (or foregoing water diversion rights in order to leave critically-needed water in its original system) and increasing the total release into the distressed section of the Colorado River by 200 cfs.
The River District, which stores 66,000 acre-feet of water in Wolford Mountain Reservoir for the express purpose of offsetting negative impacts to the Upper Colorado River Basin and Colorado’s Western Slope caused by Colorado River water diversion to the Front Range, released an additional 50 cfs on Saturday morning.
Additional water would typically not be released until late in the season when stream flows drop with decreased runoff and increased summer temperatures.
Denver Water bypassed an additional 100 cfs from the Moffat tunnel system later in the day, allowing flows to continue down St. Louis Creek into the Fraser River.
And Northern Water/Municipal Subdistrict began bypassing an extra 50 cfs out of Windy Gap on Saturday evening, water that would normally be pumped into Lake Granby.
Together, the added waters brought the Colorado River flow near Kremmling up to around 500 cfs and reduced temperatures to about 60 degrees overnight.
“Thanks to the Colorado River District, Denver Water, and Northern Water (all as members of Learning By Doing) for their quick response and coordination, and for working directly with downstream irrigators,” said Moyer, referring to the cooperative effort to “maintain, and where reasonably possible, restore or enhance the aquatic environment in the Fraser, Williams Fork, and Colorado River basins and their tributaries in Grand County, Colorado.”
But in spite of the fact that flows are remaining relatively stable several days later, water temperatures continue to peak at concerning levels during the day and there is no long-term strategy in place for how to address unprecedented water needs in a year during which Grand County and the entire Upper Colorado River Basin has begun the summer in circumstances of “exceptional drought” (according to the US Drought Monitor) and with below-average snowpack.
“Nothing will change until the Shoshone call comes on,” Moyer stated to the Grand County Board of County Commissioners on Tuesday, referencing the Colorado River’s most senior water rights holder, the Shoshone hydropower plant, located near Glenwood Springs.
When the Shoshone (or any other senior water rights holder) enacts either of its two rightful calls for water, any junior water rights holders upstream must stop diverting water until the call is filled. For communities upstream of any enacted call, it also means the derivative benefit of increased water flows through their waterways.
But the Shoshone call isn’t expected to happen until about June 25, says Moyer. “That’s still three weeks out. We need some precip.”
Moyer put forth that Grand County could potentially request an meaning the 5,412.5 acre-feet of water stored in Lake Granby for release into the Colorado River to help address a 15-mile stretch of water near Palisade and Grand Junction that is determined to be an endangered fish habitat.
That water is typically held until the beginning of August, when it is released in the amount of 35 cfs, according to Moyer, in order
to maintain a 75 cfs release out of Granby Reservoir when flows would otherwise drop to 40 cfs on August 1.
“We try to stretch that out through September,” says Moyer, “especially when the minimum flow drops from 40 to 20 [cfs] on September 1. In dry years, the 5412.5 AF water has been released earlier than August 1, in mid-late July, due to flows in the 15-mile reach for the endangered fish or as requested by Grand County due to high temperatures on the Colorado River in Grand County.”
“We can ask for the draw,” Moyer said to commissioners, “but we need it in July and August. It is not a good year–it’s just a recipe for disaster.”
He alluded to the drought conditions experienced at this time last year, a year whose hot and dry conditions led to the worst fire season in Colorado’s history. “And we had below-average snowpack this year. The soil moisture is really low. We’re starting to talk about how much melt is going into the soil and not running off–we need rain.”
In the meantime, local cooperation has proven successful so far, and the Colorado River District does have an immediate plan to help address concerns in this anticipated low-water year.
Don Meyer, CRWPD Senior Water Engineer, explains that the River District is now releasing a total of 70 cfs, continuing to “bypass inflow to meet Muddy Creek demands and maintain 50 cfs bypass Colorado River below Kremmling.”
“Due to very dry conditions in the Blue River basin, the River District will be releasing up to 26,000 acre feet from Wolford from July thru October for Denver Water, in substitution for water stored in Dillon Reservoir and owed to Green Mountain Reservoir,” Meyer described. “Williams Fork Reservoir will also participate. The volume has not been finalized, but we expect to be releasing perhaps 200 cfs beginning in July when the Shoshone Call comes on.”
Meyer observed that Denver water reduced diversion through the Moffat Tunnel again on Wednesday and is only diverting flows from the Fraser River Diversion and the Jim Creek Diversion. They are bypassing all branches of Ranch Creek and Vasquez Creek and are expected to reduce the Moffat Tunnel diversion to a “target flow” of 200 to 225 cfs.
And thanks to favorable runoff and rain conditions on the East Slope, Northern Water has only been diverting up to 50 cfs through the Adams Tunnel. And Granby, he says, is releasing 75 cfs, “typical for June.”
But if the season continues with the expected increase in drought conditions, short-term solutions may not prove enough. More work will have to be done to address the longer-term water needs of not only Grand County and the Upper Colorado River Basin but of the entire American West.
For current river information, go to waterdata.usgs.gov/. To learn more about the Colorado Headwaters Trout Unlimited Chapter, visit, coheadwaters.org/. For more information on Learning by Doing, its partner agencies, and how they’re working together to protect water and aquatic life, go to www. grandcountylearningbydoing.org/.