Warm Springs Reservoir

Warm Springs Reservoir is a reservoir on the boundary between Harney and Malheur counties in the U.S. state of Oregon. It is located 13 mi southwest of Juntura at an elevation of 3406 ft. The lake's primary inflow and outflow are both the Malheur River.

The 106 ft and 469 ft thin-arch concrete Warm Springs Dam was built from 1918 to 1919 by the Warm Springs Irrigation District, and was later modified in 1930 and 1939 with the help of the United States Bureau of Reclamation. It was constructed from 19500 yd3 of material on top of a series of olivine basalt lava flows. The resultant 8.5 by reservoir has a maximum area of 4194 acre, a maximum volume of 169714 acre.ft, and a maximum depth of 140 ft. It has a shore length of about 34.5 mi and a residence time of about 2.2 years.

Warm Springs Reservoir's watershed covers approximately 1059.5 mi2 of eastern Oregon. It receives an average precipitation of 17.5 in. As of the 2000 Census, there were 157 people living within the watershed's boundaries.

The predominant wildlife in the region is mule deer and various waterfowl. Bass, bluegill, and rainbow trout are the main fish found in the reservoir. The reservoir is classified as eutrophic, with a transparency of about 3.3 ft.