SALT LAKE CITY — Forty million people, 5.5 million acres of farmland and the livelihood of residents in major metropolitan areas such as Salt Lake City, Denver and Las Vegas depend on the Colorado River, described as the workhorse of the West and under assault by drought.
The U.S. Geological Survey is in the beginning stages of learning more about this river via an expanded and more sophisticated monitoring system that aims to study details about the snowpack that feeds the river basin, droughts and flooding, and how streamflow supports groundwater, or vice versa.
Begun earlier this year, the probe is part of a larger effort by the federal agency to study 10 critical watersheds throughout the country by expanding its monitoring capabilities.
According to the research agency, it maintains real-time monitors that provide data on the nation’s water resources, including more than 11,300 stream gauges that measure surface-water flow and/or levels; 2,100 water-quality stations; 17,000 wells that monitor groundwater levels; and 1,000 precipitation stations.
While that may seem like a lot, the network falls short of meeting the demands of modern-day analysis. The monitors in place cover less than 1% of the nation’s streams and groundwater aquifers and were designed to meet the needs of the past, according to the agency.
Because of this, the agency is investing in the Next Generation Water Observing System, which will tap sophisticated new monitoring capabilities resulting from recent advances in water science.
The effort will also bring together the knowledge and expertise of agency scientists, resource managers and other stakeholders to determine water information needs not only now, but into the future.
The system will use both fixed and mobile equipment — including drones — to collect data on streamflow, evapotranspiration, snowpack, soil moisture, water quality, groundwater/surface-water connections, stream velocity distribution, sediment transport and water use.
When it comes to the Colorado, understanding snowpack is critical because the Upper Colorado River Basin supplies about 90% of the water for the entire Colorado River Basin — with about 85% of the river flow originating as snowmelt from about 15% of the basin at the highest altitudes.
The lower basin is arid and depends upon that managed use of the Colorado River system to make the surrounding land habitable and productive.
“New monitoring technology is essential to addressing many issues associated with our annual water balance in the Upper Colorado River Basin,” said Dave “DK” Kanzer, who is deputy chief engineer at Colorado River Water Conservation District.
The Delaware River Basin, which serves big cities such as New York and Philadelphia, was the first watershed selected as the pilot watershed to study two years ago.
Selected earlier this year, the Colorado River Basin is in the early planning stages of the study, but scientists hope understanding snow accumulation and melt processes in this basin will improve the accuracy of determining water availability for downstream users and provide information relevant for other snowmelt-dominated watersheds in the western United States.