In 1999, ONDA, along with four other conservation groups, won a major legal victory when a judge ordered the BLM to permanently eliminate all cattle grazing from areas of concern on the Owyhee Wild and Scenic River.

186 miles of the Owyhee River and its tributaries are designated Wild or Scenic.  The river begins in Nevada, winding through Idaho and into Oregon through one of the most sparsely populated areas in the contiguous U.S.  Its spectacular canyons reveal 14 million years of geologic history.  The Owyhee is a popular float for rafters and kayakers who come to marvel at its canyons and paddle its whitewater.

The Owyhee Canyonlands have over 700,000 acres of potential Wilderness and 288 miles of wild and scenic rivers. The canyons are home to the world's largest herd of California bighorn sheep, 6,000 pronghorn antelope, 7 species of bats, sage grouse and songbirds, redband trout, longnose snakes, and pygmy rabbits. Innumerable archaeological and historical sites are hidden in its canyons.  ONDA has been working with other conservation groups to gain permanent protection for this remote and wild area.