Arizona State University (ASU) and Salt River Project (SRP) are collaborating with Airborne Snow Observatories Inc. (ASO Inc.) on a project to enhance water supply forecasting in Arizona. The team is using an airplane equipped with advanced scanning lidar and imaging spectrometers, combined with computational modeling from ASU, to measure snowpack in the Salt River watershed. This marks the first time such technology has been used for this purpose in Arizona.
The airborne technology was developed by NASA’s Jet Propulsion Laboratory. Data collected during the flights will be analyzed to test hydrologic forecasting models created by ASU Professor Enrique Vivoni, who leads the project as principal investigator.
“Mapping snow cover with these airborne technologies is a first of its kind for the state of Arizona,” said Vivoni, who is also part of the Arizona Water Innovation Initiative at the Julie Ann Wrigley Global Futures Laboratory. “We are excited about using snow maps in forested regions of the Salt River to improve runoff forecasts and train algorithms that apply artificial intelligence.”
The research aims to help SRP more accurately forecast runoff into seven reservoirs supplying water to over 2.5 million residents in the Valley area. Flights will focus on basin areas upstream of Roosevelt Dam on the Salt River, particularly near New Mexico’s Upper Black River Basin. A pilot and scientist will conduct several four- to five-hour flights across the basin through March, starting January 21 from Safford, Arizona.
On-the-ground SRP crews will complement aerial data by measuring snow water equivalent and depth during simultaneous surveys. According to Bo Svoma, SRP climate scientist and senior meteorologist, “This project is so critical because it will enable SRP to strengthen our measurement tools and provide more accurate data as we manage the reservoirs.”
The initiative is funded by a U.S. Bureau of Reclamation grant awarded to ASU’s Center for Hydrologic Innovation and SRP’s Innovation and Development Program, which supports collaborative research with Arizona universities on issues important to SRP operations.
ASO Inc.’s platform measures key properties like snow depth, water content in snowpack, and reflectivity—factors that vary based on precipitation, wind, temperature, and landscape features. Lidar technology emits light beams from an aircraft toward the ground; by timing their return after reflection off snow surfaces every ten feet across landscapes, scientists calculate snow depth precisely. Imaging spectrometers also assess how reflective the snow is—a factor influencing melt rates.
Processed data from these flights generate comprehensive maps of regional snow conditions used in hydrology models for seasonal tracking and runoff forecasting.
These new measurements do not replace existing monitoring systems such as SNOTEL or other SRP tools but instead fill gaps and improve predictions for reservoir management.
“The ASO data, along with satellite imagery from Planet Labs, is helping us to monitor the ephemeral snowpacks in the Salt River, which distinguish us from other parts of the Western United States,” Vivoni said. “This information is then used to feed hydrologic forecasts that provide state-of-the-art runoff predictions that help manage water supply in Arizona.”
In addition to this project focused on water resources innovation Arizona State University has been recognized as number one in innovation for eight consecutive years by U.S. News & World Report.
Patty Likens with SRP contributed reporting.
