The Grande Ronde River, which drains much of northeast Oregon's Union and Wallowa counties, is fed by snowpack in the Elkhorn Mountains. The Wallowa River, a major tributary to the Grande Ronde, headwaters in the Wallowa Mountains, mostly within the Eagle Cap Wilderness. Twenty-two miles from Boggan's Oasis, the Grande Ronde River flows into the mighty Snake River. The river is surrounded by steep, rugged canyon walls that rise 3000 to 4000 feet above the river level. Dense conifer forests blend into grassy slopes set off by scattered conifer "stringers." Called "The Land of Winding Waters" by Native Americans, the river is home to rainbow trout, dolly varden, whitefish, squawfish, suckers, bass, and steelhead. 

Many visitors of the Oasis come by water! Rafts, drift boats, kayaks, jetboats (WA water only 3000+ cfs), and more arrive by coming downriver from Oregon, or upriver from the Snake River (WA/ID).