Summary: In 2015, the Omaha District initiated a dam safety modification study in response to Cherry Creek Dam receiving an elevated risk rating through the USACE risk characterization process primarily because of the dam’s large downstream population and the potential for overtopping issues during an extremely rare precipitation event. A series of public scoping meetings were held in cooperation with the Denver Office of Emergency Management Homeland Security to begin development of an Environmental Impact Statement (EIS). After incorporating public comments and conducting detailed economic and risk analysis, the draft EIS recommends No Action.
Although the recommended plan is No Action, the dam safety study did identify maintenance issues with the Cherry Creek Dam spillway. Over time, sloughing of soil along the sides of the spillway has increased the spillway’s crest elevation approximately 12.5 feet and reduced its capacity to carry water. Because this has been identified as a maintenance issue, the Omaha District is pursuing a spillway cleanout project using operation and maintenance funding.
Geographic Scope: Cherry Creek Dam, Arapahoe County, Colorado
Decision/Date: Made following close of public comment period.