Groundwater Salinity in Wyoming

The Wyoming State Geological Survey (WSGS) used data from more than 11,500 groundwater quality analyses obtained from the U.S. Geological Survey Produced Water Database and the Wyoming Oil and Gas Conservation Commission to evaluate groundwater salinity in Wyoming. Saline groundwaters occur most frequently in the Denver-Julesburg Basin (43 percent of all wells tested) and the Overthrust Belt (30 percent), followed by the Powder River (27 percent), Laramie (23 percent), Great Divide and Washakie (22 percent), and Bighorn (21 percent) basins. Saline wells are found with less frequency in the Wind River (20 percent), Green River (18 percent), and Hanna (11 percent) basins. No saline wells are recorded in the Jackson Hole, where oil and gas exploration has been limited. The locations and geologic units of sites that produce saline waters were largely determined by exploratory oil and gas drilling. Consequently, the sample sites shown in the figures presented in this report are clustered in Wyoming’s oil and gas fields. To access an interactive map from Wyoming State Geological Survey, please see: https://arcg.is/be1Hq