History of the Dam & Reservoir

The McKay Dam is an impoundment of McKay Creek, a tributary of the Umatilla River in Umatilla County, Oregon, and is located six miles south of Pendleton on U.S. Route 395. The McKay Dam was built between 1923 and 1927 as a project of the United States Bureau of Reclamation (BOR), part of the Umatilla Basin Project that had started in 1908 with the nearby Cold Springs Dam. Modification of the spillway section was made in 1978-1979 to increase the capacity from 10,000 to 26,910 cubic feet per second.

The dam is an earth-fill dam with a reinforced concrete paved upstream slope. It stands 165 feet high and contains 2,364,000 cubic yards of material. At closure in 1927, the reservoir had a total storage capacity of 73,800 acre-feet, but a sedimentation survey in 1993 pegged the current active capacity of 71,534 acre-feet (88,236,000 cubic meters), of which 6,000 acre-feet (7,400,000 cubic meters) is used exclusively for flood control. The spillway section of the McKay Dam was modified 1978 through 1979 to increase the capacity from 10,000 to 27,000 cubic feet per second.

The reservoir is jointly managed by the BOR and the U.S. Fish and Wildlife Service (FWS) for irrigation water and habitat for a variety wildlife, including osprey, bald eagles and an abundance of waterfowl. The reservoir furnishes supplementary water to the Stanfield and Westland Irrigation Districts.

Quick Facts:

• Structural Height — 165 Feet.0
• Hydraulic Height (Normal Operating Depth at Dam) — 158.0 Feet
• Spillway Crest Elevation — 1,329.3 Feet
• Crest Elevation — 1,330.0 Feet
• Crest Length — 2,700.0 Feet
• Top of Active Conservation Pool (Elevation) — 1,317.1 Feet
• Total Water Storage at Elevation — 65,534 Acre-Feet, Plus 6,000 Acre-Feet Flood Space to Elevation 1,322 Feet
• Normal Water Surface Elevation — 1,317.1 Feet
• Spillway Type — Gated
• Auxiliary Spillway — No
• Spillway Capacity at Elevation — 26,910 Cubic Feet/Second at 1,329.3 Feet
• Outlet Works Capacity at Elevation — 1,240 Cubic Feet/Second
• Drainage Area — 186.00 Square Miles

History of the National Wildlife Refuge

McKay Creek NWR is an “overlay refuge” of the BOR’s Umatilla Irrigation Project. It was established as the "McKay Creek Bird Refuge" on June 7, 1927, through Executive Order 4662 from President Calvin Coolidge. The President's order transferred management of the lands—as related to wildlife—from the BOR to the Department of Agriculture as "a refuge and breeding ground for birds." Changes in the government (e.g., bureaus being created, disbanded and consolidated) over the years has resulted in McKay Creek NWR coming under the management of the FWS. Public Land Order 1366 (November 27, 1956) issued by the Secretary of the Interior withdrew additional public lands to enlarged the refuge by 23.5 acres. Through a formal agreement between the FWS and BOR (August 25, 1955) the FWS took over primary management of fish and wildlife resources. The agreement has been renewed over the intervening years and is still in effect.