Colorado water officials will gather in Durango this week to decide whether a pair of powerful Colorado River rights can be used to benefit the environment.
The Colorado River District, supported by a broad Western Slope coalition, has entered into a $99 million agreement with Xcel Energy to buy two key water rights tied to Shoshone Power Plant, located on the Colorado River near Glenwood Springs. Part of the deal is to add a newly approved use to the existing water rights: keeping water in the river to help the aquatic ecosystem.
That environmental use, called an in-stream flow right, requires approval from a state water agency, the Colorado Water Conservation Board. If the board decides not to add the Shoshone rights to its Instream Flow Program, the Colorado River District would have to start from scratch. Its goal is to maintain the status quo flows permanently to have greater water security on the Western Slope.
People are eager to weigh in: They filed about 5,100 pages of documents to make their arguments in the months leading up to this week’s hearing.
“We’ve been presented with a tremendous amount of material,” said Greg Felt, who represents the Arkansas River Basin on the state water board. “I’m just trying to make good use of time to sift through all of those rebuttal statements and look for different potential paths forward.”
By early August, more than 200 members of the public voiced support alongside a broad mix of Western Slope water districts, governments and community groups.
Front Range water providers and managers — like Aurora Water, Colorado Springs Utilities, Denver Water and Northern Water — opposed parts of the proposal even while supporting the overall environmental benefit.
These providers are responsible for sending water to millions of homes, businesses and farms. They are worried their water supplies could be negatively impacted and raised questions about how the Colorado River District estimated past water use at Shoshone. Some asked for more time to negotiate a proposal. (The board must decide on a proposed in-stream flow acquisition within 120 days, a time period triggered in May.)
The hearing is scheduled to begin Wednesday and end Thursday. Members of the public can attend in person at Fort Lewis College, via Zoom or the YouTube livestream.
Board members must decide whether to acquire the two water rights, owned by an Xcel Energy subsidiary. Shoshone’s 1905 water right allows the power plant to divert up to 1,250 cubic feet per second of water. A second, more recent, water right allows the plant to divert 158 cfs.
The small, aging hydropower plant’s 1905 water right is old enough and large enough to impact up to 10,600 other upstream water rights. Some of those upstream rights send water from the Western Slope through tunnels and across mountains to Front Range communities.
Even if the board accepts the environmental use, it has to go through a water court process before it can be finalized. This multiyear process includes steps where water users can make sure their water rights will not be negatively impacted by the proposed change.
A closer look at the environmental potential
But what exactly could Shoshone’s water rights do to help the environment?
Shoshone Power Plant generates hydropower by, first, taking water out of the Colorado River. It does this at a nondescript dam, called Hanging Lake Dam, next to Interstate 70 about 9 miles east of Glenwood Springs.
This dam is located about 2.4 miles upriver from the Shoshone Hydroelectric Facility, where water spits back out into the Colorado River.
The power plant can pull up to 1,408 cfs of water out of the river. Sometimes, there’s more than that amount of water flowing through the Colorado River, like during spring runoff season when the snow is melting.
Sometimes, the river flows at 1,400 cfs or less, like in the late summer season or during the winter. In that scenario, the power plant can pull almost all of the water out of the river, leaving a trickle flowing down the river channel while the rest goes through pipes to the facility.
That can be a problem for fish species, macroinvertebrates and the health of the river ecosystem for that 2.4-mile stretch.
When water is plentiful — when the river is naturally gushing or the power plant is not diverting water to generate electricity — there is plenty of room for fish to zig-zag between rocks, take refuge from eagles, otters and minks, or find a comfortable temperature zone.
Fish species can travel upstream and downstream more easily without having to make large jumps over boulders. The 2.4-mile stretch, called the Shoshone reach, is home to brown trout, rainbow trout, whitefish, dace, sculpin and suckers. The reach is a popular fishery for anglers.
Three species of native fish, bluehead sucker, flannelmouth sucker and roundtail chub, travel through the reach, according to the Colorado Parks and Wildlife analyses.
These native fish can live up to 30 years and sometimes travel dozens of miles from good forage areas to good reproductive habitat. Their habitat is threatened when streamflows change — like when dams divert large amounts of water — predators and nonnative competitors. Their range has declined by 50%, CPW said.
But when Shoshone is diverting water, it’s a different story.
“If you’re flying by on I-70, you’ll think that river is like, totally dewatered, and there’s like a tiny thread of a channel,” Kendall Bakich, a CPW aquatic biologist said during a May presentation to the CWCB. The CPW declined requests for a follow-up interview.
Fish in the river are packed into the narrow channel, she said. CPW found 300 fish per acre in the Shoshone reach when the power plant was diverting water.
This is a good time for anglers and predators to go fishing, but fish have a hard time escaping. Underwater, they want to defend their territory, but when they rub fins with their neighbors, they get stressed, Bakich said. The close proximity also enables the spread of disease.
In the winter, low flows allow ice to stretch down and anchor onto rocks that would otherwise provide habitat for fish and macroinvertebrates. In 2010, so much ice formed that it blocked up the dam and the river stopped for two days, Bakich said.
Low flows are also a problem near natural hot springs: There is less cold water to dilute the hot water, and the high temperatures have killed fish in the past. In the summer, shallow, low water becomes too warm and can also stress or kill fish.
There is a diverse aquatic ecosystem in the reach currently, the CPW analysis found, but increasing flows more regularly through the area will help.
But environmental benefits are only one of the criteria board members will need to consider this week. They also will consider the location of other water rights, return flows, downstream users and other factors.
That’s where the nuance comes in, Felt said.
“As a state, we have been presented with a pretty amazing but also challenging opportunity,” he said. “I don’t think it’s all about yes and no. How do we get it just right?”