Oreana Reservoir   Be the first to submit input for Oreana Reservoir. If you have info on Oreana Reservoir, Harney County, Oregon please submit it here to improve this web site.          These outdoors activities are available near Oreana Reservoir.   Hiking Trails Near Oreana Reservoir: The Beef Trail, Harney County, 12 miles away       5 hiking miles, 644 feet elevation difference