The property on which the dam and spillway are located is owned in part by Lakeside Village Properties and in part by Oklahoma County, documents indicate. The dam and spillway were built in 1962, almost four decades ago, to impound the lake for recreation and aesthetics associated with residential and apartment development in the vicinity of the lake, Barnett related. Blueprints indicate the rolled earthen dam is 15 feet high and 300 feet long, with a concrete emergency spillway 46 feet wide. The upstream slope of the dam has eroded from lapping waves. The crest of the dam has eroded on the upstream slope to the point that, in some sections, the crest is only 4 feet wide, half its original width.
Water flows beneath the control section of the spillway.
Consequently, dirt underneath the center of the emergency spillway has washed out and the concrete has collapsed into a hole measuring approximately 6 feet wide by slightly over 10 feet long and almost 4 feet deep. The downstream toe of the dam is saturated from seeping water that has created a permanent wetland. At least two deep pedestrian and bike trails have been cut into the face of the earthen dam, and at least one utility pole has been planted in the shoulder of the dam. Plants of all sizes, ranging from saplings to grown trees and brushy vegetation, are growing on the dam and the control section of the spillway. A professional engineer testified that hydrology analysis showed that if the dam collapsed, the Wilshire Village apartments approximately 1,000 feet downstream would be flooded.