Wyoming Surface Water

The use of Wyoming’s water is managed by the Wyoming State Engineer’s Office. The Wyoming Department of Environmental Quality monitors water quality. These agencies serve important roles in the management of Wyoming’s water resources. Any events—changes in climate, drought, vegetation change, fires, insect outbreaks—that impact our mountain watersheds will have major consequences for all Wyoming water users and water users downstream.

Wyoming is the fifth driest state in the United States. More than 70 percent of the state receives less than 16 inches of precipitation on average each year. At 6,700 feet, Wyoming also has the second highest mean elevation in the United States. Mountain snowpack runs off to form the headwaters of Wyoming’s major river systems and helps recharge aquifer systems.

Three of America's major river systems have their headwaters in Wyoming: the Missouri, Colorado, and Columbia. Other major rivers include the Yellowstone, Bighorn, North Platte, Green, and Snake.

Surface Water Map of Wyoming

The Wyoming State Geological Survey in 2009 released Surface Water Resource Map of Wyoming: Streamflows and Storage, showing streamflows and surface water storage in Wyoming. This unique and comprehensive map product includes current and historic streamflow and reservoir capacity data.

The map is available as a free download or for purchase in hardcopy with accompanying CD that illustrates the minimum, average, and maximum streamflow rates at 330 U.S. Geological Survey gage locations across Wyoming and the maximum storage capacities of reservoirs and volumes of major lakes. The map also features watershed boundaries, surface water facts and trivia, tables of the 10 largest lakes and rivers, and inset maps of structural geology and the headwaters and routes of Wyoming rivers.

Water map
Download Surface Water Resource Map of Wyoming: Streamflows and Storage.


Kurt Hinaman, kurt.hinaman@wyo.gov