Cheyenne has for decades relied on elaborate engineering and water rights trades to get most of its water from the headwaters of the Colorado River.
With that likely to dry up, the city could be left with few alternatives, and looking to Laramie County ranches for water probably won’t work, a Wyoming water expert said.
“It’s really not a matter of if, it’s a matter of when that Colorado River water is going to be in jeopardy,” Jim Pike Cowboy State Daily. “The problem then becomes, what kind of move does Cheyenne make next?”
Pike came to Laramie County in 2007 and began serving as a water conservation specialist for the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS). He retired a few years ago, but said he’s still concerned about the future of the county’s water supply as Cheyenne continues to grow – and get thirstier.
Looking West Not An Option
Getting more water from ranches west of the city probably isn’t a good option, Pike said.
The city has in the past, for example, used several wells on the Polo Ranch West of Cheyenne and F.E. Warren Air Force Base, he said.
“There is a large cone of depression out there in the groundwater levels,” he said.
Tim Dawson of Laramie County, a veterinarian who lived on the Polo Ranch for time, agreed.
“Out there on the Polo during a dry year, literally, the kitchen sink was shooting air,” he told Cowboy State Daily.
Dawson said the ranch’s original owner John Morris, who died in 2014, told him how the ranch was an “Oasis” back in the 1950s. But during some recent years, Crow Creek hasn’t even flowed through the property. Instead, the water disappears into fissures and flows entirely underground, leaving the creek bed dry.
Morris and his family were involved in lawsuits against the city of Cheyenne over water use, and some ranchers to the west still blame the city for drawing their water tables down, Pike said.
Weaning Off The Colorado River
The headwaters of the Colorado River are at the opposite end of Wyoming, but Cheyenne has for decades sourced up to 70% of its water from there.
Cheyenne’s links to the Colorado River are complicated, Brad Brooks, directory of the city’s Board of Public Utilities, recently told Cowboy State Daily.
In western Wyoming, the Little Snake River flows into the Yampa River, which flows into the Green River, which in turn flows into the Colorado.
Water from the Little Snake River is piped from the western side of the Continental Divide through a ¾-mile-long tunnel near Encampment, Brooks said. From there, it flows into Hog Park Reservoir, then into the Encampment River and finally into the North Platte River.
However, Cheyenne is supplied through Rob Roy Reservoir in the Snowy Range Mountains, Brooks said. Water flows from there into the Douglas drainage and also into the North Platte.
There is a “gallon-for-gallon” trade between the water coming out of the Little Snake River and that coming out of Rob Roy Reservoir, he said.
The system dates back to the 1960s, and water rights that were drawn up in the 1950s, Brooks said.
Up until now, that system has supplied Cheyenne with more than enough water. However, there’s increasing concern that volatile politics downstream could change that. Particularly in the Lower Colorado River, squabbles between states such as California and Arizona – as well as the Navajo Nation’s ongoing dispute over water with Arizona – have heated up.
It's feared that those cantankerous politics could reverberate back upstream. That cold result in the culling of some relatively recent water rights, including Cheyenne’s roundabout claim to the Colorado River Headwaters.
Out in Laramie County, a large portion of the water from local sources comes from wells that supply overhead pivot irrigation on cropland, Pike said.
Most of those farm wells date back to the 1950s or so, he said. However, he questions the long-term efficiency of that, given the relatively sparce growing capacity on such naturally arid, high-altitude ground.
During his tenure with the NRCS, Pike said he convinced many farmers to simply give up pivot irrigation and let their land go dry. The agency paid them anywhere from $900 top $1,800 an acre to do so.
“Thirty to 40 years had passed and their wells were getting weaker. A lot of those wells had declined from 900-1,0000 gallons per minute to 300-600 gallons per minute,” he said. “Maybe their irrigation pivot was wearing out, and it costs $100,000 to replace one of those pivots.
“And a lot of those farmers were in that age group where they weren’t interested in re-investing that kind of money.”
In many cases, those irrigation buyouts helped water tables fill back up, Pike said.
Quit Punching Wells?
Farmers and other county residents also formed a “county control area” west of Interstate 25, which forbid any new water wells, he added. However, when there was an oil boom in parts of Laramie County in 2015, the state superseded that so companies could dig wells to supply water for fracking.
That policy was supposed to be reviewed in 2020, but it wasn’t, Pike said.
Now, he’s concerned that continued demand for new wells will just keep making things worse as the city, county, farmers and housing developers all compete for dwindling water supplies.
Meanwhile, he favors continuing to try convincing farmers to shut down pivot irrigation.
“I think we’re in good enough shape,” he said. “If we can get the city, the county and the state working together, I think this problem is solvable.”
Some ranches could still rely on natural flow, such as from Crow Creek, Dawson said. Particularly after heavy snow winters like this one, the Cheyenne could do more to capture runoff from snow in reservoirs in the Laramie mountains.
That would be better than letting everything blast through the low country in a rapid runoff and escape useful application, he said.
Pike added that surface water and groundwater need to be managed as a single resource, with an eye toward long-term conservation. Unfortunately, the status quo has been that “water flows toward money.”
Dawson agreed that it can come down to money.
“You’re going to generate a lot more tax revenue from 5 acres with domestic well and a house on it than you are going to generate from 5 acres of prairie grass that some old boy is running cattle on,” he said.
Photo: Pivot irrigation may be something Laramie County farmers will have trouble maintaining as Cheyenne's share of Colorado River water dwindles. (Getty Images)