The U.S. Army Corps of Engineers, Walla Walla District supplemented the National Environmental Policy Act documentation for the operation and maintenance (O&M) program for the Federal and non-Federal levees that make up the Jackson Hole Flood Protection Project (JHFPP) along the Snake and Gros Ventre Rivers near the town of Jackson in the northwest corner of Wyoming.

The Supplemental Environmental Assessment (SEA) evaluated current and proposed O&M actions and associated potential environmental effects that may not have been adequately addressed in the April 1990 Jackson Hole, Wyoming Flood Protection Project O&M Decision Document and Environmental Impact Statement (1990 O&M Decision Document EIS) (Corps, 1990). The SEA is tiered to and incorporates by reference the 1990 O&M Decision Document EIS.

The Corps will continue to continue to operate and maintain the JHFPP consistent with its authorized purposes, while minimizing adverse effects to the environment.  The Finding of No Significant Impact was signed in June 2018.