Flood Control Act approved July 3, 1958, (Public Law 85-500) HD 170, 85th Congress. 1st Session and the Flood Control Act approved October 23, 1962. SD 137, 87th Congress 2nd Session. Modified in Section 102(v) of WRDA 1992 (106 Stat 1187), Section 338 of WRDA 1996 (110 Stat. 1808) and further modified to require seasonal adjustments to the Top of Conservation Pool in WRDA 1999.
Location: On the Mountain Fork River a tributary of Little River at river mile 20.3, about 9 miles north-northeast of Broken Bow in McCurtain County, Oklahoma.
Purpose: Flood control, hydroelectric power, water supply, recreation, and fish and wildlife.
History of Construction: Construction began in October 1961. Impoundment began in October 1968 and the conservation pool was filled in April 1970. The first power unit was put on line in January 1970 and the second unit in June 1970.
Type of Structure: The dam is a rolled, earth-filled sturcture about 2,750 feet long rising 225 feet above the streambed. The total length of the dam, dike and spillway is 4,026 feet.
Spillway & Outlet Works: The controlled spillway is a concrete ogee weir located in a saddle about 1.25 miles northwest of the right abutment of the dam. Total length of the structure is 376 feet with a clear opening of 320 feet. The structure is controlled by eight 40-foot by 40-foot tainter gates. Design capacity of the spillway is 443,000 cubic feet per second. Seven 8-foot wide piers support a roadway bridge across the spillway. Operating channel capacity below the dam is 8,000 cfs.
Hydrologic Data: The flood of record, as recorded on the Eagletown gage, occurred in 1945 with a volume of 1,047,700 acre-feet, which is equivalent to 26.05 inches of runoff from the upstream drainage area. The maximum discharge was measured as 101,000 cfs on May 20, 1960. An average daily inflow of 76,600 cfs occurred on May 3, 1992. The flood of record since impoundment occurred in May 2009 with the pool cresting at 627.50.