The Wyoming State Geological Survey (WSGS) has completed a groundwater study of the Powder/Tongue/Northeast River Basins (NERB) in northeast Wyoming for the Wyoming Water Development Commission (WWDC). The study is part of an overall effort to assess groundwater in river basins throughout the state. This was a multi-year project funded by the WWDC.

The NERB encompasses the entire northeast quarter of Wyoming, and includes headwater drainages of the Little Bighorn, Tongue, Powder, Little Powder, Little Missouri, Belle Fourche, Cheyenne, and Niobrara rivers. The waters from all eight rivers flow ultimately to the Missouri River.

Major sandstone aquifers include the Arikaree, Wasatch, Fort Union, Lance, and Fox Hills formations and the Inyan Kara Group. The Tensleep and Minnelusa formations and the Madison Limestone are productive limestone aquifers. Of these aquifers, the Wasatch-Fort Union aquifer system has been the most heavily produced.

The Technical Memorandum is available for free download.