This 825-foot-by-140-foot auxiliary concrete spillway is constructed on an existing earthen dam at the Corn Hydroelectric Plant in Gadsden County, Florida. The project features an ogee concrete spillway, 2,050 linear feet of steel sheet pile cutoff walls, and 1,700 linear feet of earthen dam extension. This isolates and eliminates the current fuse plug and emergency spillway system, and will pass 69,900 cubic feet of water per second when the upstream reservoir, Lake Talquin, reaches its maximum stage of 77 feet. The new auxiliary spillway system provides the Corn Hydroelectric plant with an increased level of safety mandated by the Federal Energy Regulatory Commission.
The client requested that PCL meet two primary objectives in managing the existing Corn Hydroelectric dam during construction: maintain the safety of the public, and maintain Lake Talquin's status as a recreational lake and vibrant environment. As part of the first objective, the client required the project to be constructed outside of Florida's hurricane season, leaving only six months to complete the work. Through careful planning, close collaboration with the design engineer, and timely execution of the work, the project team safely completed construction within a timeframe that mitigated serious risk and satisfied the client's needs. The project team also accomplished this with no impact to the public's use of the lake and while maintaining its environment.