NEWS RELEASE: Wyoming Geological Survey Publishes Report on Groundwater Salinity in Wyoming

WSGS Publishes Report on Groundwater Salinity in Wyoming

The Wyoming State Geological Survey (WSGS) recently published a report that examines the salinity of groundwaters that occur throughout Wyoming, and explores the relationship between salinity and depth-of-sample in selected geologic formations.

“Using groundwater appropriately is important for preserving this precious resource,” says Dr. Erin Campbell, state geologist and director of the WSGS. “By identifying groundwater sources that aren’t consumable by humans or livestock, or usable for irrigation, industry may be able to utilize low-quality water and leave higher-quality water in place.”

Groundwater quality varies widely throughout Wyoming’s geologic basins, which serve as home to most of the state’s population and economic activity. An aquifer may produce high-quality groundwater suited for human consumption at a basin’s edge, while water pumped from the same aquifer a few miles further into the basin may be unfit for livestock usage.

One measure of water quality is its “salinity,” or TDS, which is the amount of dissolved material that remains as residue after the liquid portion of a water sample evaporates. Salinity, measured in milligrams per liter, is one constituent, among others, used by the Wyoming Department of Environmental Quality to determine if groundwater resources are suited for human consumption, agricultural application, or livestock watering. Although salinity provides a general measure of water quality, it does not specify the type or amounts of particular chemical compounds present.

“The results of this study show that naturally occurring groundwater salinity varies widely within individual geologic formations, at different depths, and throughout the state,” says Karl Taboga, WSGS hydrogeologist.

WSGS geoscientists investigated thousands of water quality analyses from the U.S. Geologic Survey (USGS) and the Wyoming Oil and Gas Conservation Commission. The publication also includes an explanation of groundwater salinity and maps of water quality by salinity level throughout Wyoming.

“Groundwater Salinity in Wyoming: Open File Report 2020-6,” is available as a free download from the WSGS website. The report follows a series of studies examining the occurrence of industrial-grade groundwater in Wyoming’s structural basins. Previous reports published in the series examined the salinity of groundwater in the Denver-Julesburg Basin in southeastern Wyoming and the Powder River Basin in northeastern Wyoming. The statewide salinity report supplements the recently released USGS report, Brackish Groundwater in the United States.