from Hub Pages "Oklahoma Attractions: Fun things to do in Okmulgee, Oklahoma"
The Okmulgee Spillway, built in 1939-1940 by the Works Projects Administration, sits at the northeastern most point of the Lake Okmulgee Dam. The 40-foot-high by 250-foot- long cascade which is being nominated, is a series of upwardly rising limestone steps which buttress the original 1927-28 spiliway (built by a private contractor), on the dry side of the dam. Stone retaining walls buttress the dry side cuts that were made into the dam to accommodate the spiliway. The retaining walls are stepped upward from the creek floor, providing access up and down the slope. The center of the stepped cascade is additionally buttressed by a 72 x 72 foot stone platform. The floor of the creek is paved with stone blocks as well. Across the creek from the cascade, a stone retaining wall follows the line of the highway and prevents washouts from Lake Okmulgee. This is the only such flood control/recreational structure of this design, material, and workmanship in Okmulgee County.