Colorado rivers may shrink by 30% as climate change continues, report says

Climate change will continue to hammer Colorado’s hallmark rivers and streams, with a new report showing their flows will shrink by 5% to 30% over the next nearly 30 years.

And it’s not just drying up our water.

Human-caused global warming has raised Colorado’s annual average temperature by 2.3 degrees between 1980 and 2022, the report says. Colorado climate change, exacerbated in the fall months and in the southwestern and south central parts of the state, will add another 1 to 4 degrees of average temperature by 2050.

The news comes with the release early this week of the Colorado Climate Report, the third in a series of papers the state has issued since 2008 documenting the impact of the warming climate.

Beyond drying rivers, the steady heating of Colorado will worsen toxic ozone pollution along the Front Range, drive more wildfire danger and push wildlife further out of current comfort zones, according to climate experts from environmental groups who saw the embargoed report.

And the emergencies will tend to become the norm. Within 26 years, the report says, our “normal” years will be as hot as the hottest years leading up to 2022.

“Those are alarming numbers,” said State Sen. Dylan Roberts, D-Frisco. Roberts is among several Colorado lawmakers working on legislation to cushion the blows of a warming climate.

“Coloradans who depend on rivers and streamflow for agriculture and recreation notice if a stream dips even a couple of points,” Roberts said. “To hear of a 30% reduction is shocking and really concerning. But looking forward, that also gives support and credence to what we’re trying to do now, which is preparing Colorado for that reality and doing with less water.”

Extreme heat will also become more common and dangerous.

“The wild beauty that is at the heart of our state identity is at risk,” said Heidi Leathwood, climate policy analyst with the nonprofit advocacy group 350 Colorado. “The expected temperature rise and increasingly more frequent and severe heat waves will hit all of us hard, but will continue to hit low-income communities and people of color even harder unless the state takes immediate and effective steps toward environmental justice.”

Farmers, kayakers and anglers are likely to feel the impact the most with urban users feeling less of the pain, said Becky Bolinger, assistant state climatologist and a co-author of the report.

Agriculture uses as much as 80% of the water generated in Colorado and as its take shrinks, the productivity of farm fields will shrink also. The industry contributes $47 billion to Colorado’s economy, according to the Colorado Department of Agriculture.

Farmers already wrestling with a long-term drought and warming temperatures, face tough choices, said Joel Schneekloth, a specialist in irrigation practices and agricultural water use at Colorado State University.

“Growers are already dealing with declining [water] supplies,” said Schneekloth, who works with farmers in the South Platte and Republican river basins. “Years ago they had wells that could pump 600 to 700 gallons per minute. Now some are down to 200 to 300 gallons per minute.”

As a result, he said, “We know some of these areas are going to come to an end. … It’s not a rosy picture.”

At the same time, the state’s $13.9 billion skiing, rafting and fishing industries will also take a hit, as streams shrink, and the timing of the skiing and rafting seasons grow shorter and shift.

“Of course we’re concerned,” said Andy Neinas, a 37-year veteran of Colorado’s rafting industry whose company, Echo Canyon River Expeditions, survived the droughts of 2002, 2012 and 2018.

“Those hit us on our head, and we had to learn to adapt,” he said of the drought years. “So we changed the logistics of our trips, changed the duration, and we started using smaller craft [able to float on smaller streams]. And though we are known as white water outfitters, a lot of what we do is scenic, so even though water levels may be lower, it doesn’t change the value of the scenery and the experience of being out in nature.”

Urban areas consume just 7% of state water supply

Environment advocates said the continuing pattern of warming anticipated by the study is cause for extreme worry — and action.

“With the projected declines in snowpack, and the increases in wildfires, heatwaves and dry conditions, the outdoor recreation industry is at extreme risk, our agricultural industry will suffer, and outdoor workers and those living without air conditioning will be in increasing danger,” Leathwood said.

“Nowhere will communities be safe from the threat of wildfire which could strike at any time and place. It will be increasingly difficult or even impossible for wildlife to adapt,” Leathwood said.

Urban areas are likely to feel the least impact, Bolinger said, because they use just 7% of the state’s water and have flexibility in managing their water supplies each year.

Looking ahead, Bolinger said there are hopeful trends, largely in the way Colorado is already adapting to climate change.

“It’s scary to look at some of these numbers … but with reports like this, you’re increasing awareness of the issues and as long as we’re planning we can be better prepared for a lot of events that will inevitably occur. It makes you feel not quite so helpless when we know there are things we can do to protect ourselves and our ecosystems,” she said.

Environmental advocacy groups want Colorado lawmakers to go well beyond adapting to conditions. They say the report underscores why they will be working at the 2024 legislature and beyond on policy changes to combat global warming, at what they see as the prime source: the fossil fuel industry.

“The oil and gas industry in particular is a significant contributor to several of the costly crises discussed in the report,” said Ryan Maher, staff attorney for the Center for Biological Diversity. “The industry puts pressure on limited water resources. It’s the single largest anthropogenic cause of Colorado’s ozone problem, which will only worsen with higher temperatures from climate change. And the industry’s ozone is itself a dangerous greenhouse gas.”

Colorado regulators are still letting oil and gas companies “off the hook,” Maher said. They are permitting too many new oil and gas wells, failing to enforce leak regulations on existing wells, and allowing drilling and production on the hottest summer days in a way that worsens the ozone problem on the Front Range, the advocates say. Nine northern Front Range counties have been categorized by the EPA as “severe” violators of toxic ozone regulation, and face various sanctions as a result.

“This report underscores that if the Polis administration doesn’t get serious about phasing out drilling and fracking, Colorado stands to suffer tremendously,” Maher said.

Dan Haley, president of the Colorado Oil and Gas Association, responded that environmental advocates should stop trying to drive fossil fuel production out of Colorado.

“As an industry, we have decreased greenhouse gas emissions, such as methane, in Colorado by more than 70 percent over the past decade, and our scientists and engineers work each day to reduce it further,” Haley said.  New technology and tight regulation means that in coming years, “the state’s emissions profile from this industry likely will continue to decrease,” Haley said. “The world will need more energy to survive and thrive in the 21^st century,” Haley said, “and it should come from places like Colorado that protect the environment.”

Fresh Water News was launched in 2018 as an independent, nonpartisan news initiative of Water Education Colorado. Our editorial policy and donor list can be viewed at wateredco.org.