Western lawmakers make moves to improve snow measurement in Colorado River Basin

Western lawmakers, including U.S. Sen. John Hickenlooper of Colorado, want to know — exactly — how much snow and water is in the Colorado River Basin.

The legislators Thursday introduced a bill focused on improving how the basin measures its water supply. It’s a tough subject: Rising temperatures, prolonged drought and persistent demands have cast uncertainty over the future water supply of 40 million people. With better measurement techniques, water users will be better prepared to decide how to manage reservoirs, put water on crops and manage drinking water systems, according to Hickenlooper, a Democrat, and U.S. Sen. John Curtis, a Republican from Utah.

“You can’t manage what you can’t measure,” Hickenlooper said. “Snowmelt is Colorado’s largest reservoir. Leveraging advanced snow monitoring tech will give us more accurate water predictions and unlock a better understanding of how to make the most of our water in an era of extreme drought.”

Coloradans watch snow data closely: Farmers need it to decide how much of which crop to plant, and reservoir operators use it to balance dam releases and reservoir storage. It impacts city utilities and lawn watering restrictions in the summer.

The accuracy of snow and water monitoring has become even more pressing in recent years. Rising temperatures pose a threat to the basin’s water supplies, and the river’s annual flows are shrinking. In some cases, an average snowpack has produced a much less-than-average flow of water down streams and into irrigation ditches. 

In Utah, an average winter snowpack produced a “shabby” runoff, about 54% of the norm, according to state officials at an Upper Colorado River Commission meeting in June.

For water officials, a tighter, less-predictable water budget puts more pressure on gauging just how much water is in the snowpack and how much can make it down streams to ecosystems and communities.

The newly proposed bill aims to address this by reauthorizing the Bureau of Reclamation’s Snow Water Supply Forecasting program through 2031.

The bill highlights focus areas for the program, like being more responsive to changing weather and watershed conditions, informing water management decisions at local up to interstate levels, and building the program’s capacity so it can adapt to new forecasting and measurement capabilities. 

The bill would also support different measurement technologies like imaging spectroscopy, machine learning, and integrated snowpack and hydrologic modeling. 

It would increase the program’s budget from $15 million over five years to $32.5 million over five years.

This week, the companion legislation in the U.S. House — put forward by Colorado U.S. Reps. Joe Neguse, a Democrat, and Jeff Hurd, a Republican — advanced out of the House Committee on Natural Resources.

The effort could face headwinds under President Donald Trump’s administration, which has slashed budgets, cut staffing at the Bureau of Reclamation, decreased federal science funding and removed national climate assessments from federal websites, according to news reports.

The state wants better measurements, too

At the state level, Colorado lawmakers took similar steps this year to take water measurement to the next level.

In May, Gov. Jared Polis signed House Bill 1115 into law. The law authorized the Colorado Water Conservation Board, a state water policy agency, to create a program that collects and shares data on snowpack levels with a budget of about $105,000 for fiscal year 2025-2026. The goal was to help the state navigate water conditions in a changing climate, according to a news release in May. 

The state program will also delve into advanced technologies for snow measurement, like airborne and remote sensing tools.

That’s the kind of work that Airborne Snow Observatories Inc. has been doing for local communities around Colorado. The ASO team members use lasers, planes and their own two feet to calculate how much water is in the mountain snowpack. 

This measurement technique, developed at NASA’s Jet Propulsion Laboratory, captures one snapshot of an entire watershed. When ASO flies over a watershed, lidar technology on the bottom of the airplane sends pulses of laser light to the ground to take snow depth measurements every 10 feet across all elevations in the watershed on a particular day.

This technique fills in the gaps of the longstanding snow-telemetry, or SNOTEL, network, which has been operated by the Natural Resources Conservation Service for decades and is a primary source of information for water managers.

The network is made up of over 900 stations in the West, 114 of which are in Colorado. Sensors at each station take measurements at one carefully chosen location in a watershed, and then use that data to model the amount of water in the snow across a larger area. The continuous measurements give researchers and water managers long-term, up-to-date information at one particular location within a watershed.

“Managing water in the West starts with understanding our snowpack,” Jeff Deems, CTO and co-founder of ASO, said in a prepared statement supporting the new federal bill. “This bipartisan legislation recognizes that better data leads to better decisions — for communities, farmers, water utilities, and ecosystems.”

The lawmakers announced the bill just before Colorado River Day, which celebrates the day when Congress officially changed the river’s name from the Grand River to the Colorado River on July 25, 1921.  

“In the West, water is everything — our economy, our communities and our way of life depend on it,” Curtis said. “This bill brings 21st century tools to one of the oldest challenges we face: knowing how much water we’ll have and when.”