Truth and Consequences: How Studying the Truth Behind Updated Hydrology and Evaluating Downstream Consequences Saved Millions of Dollars in the Rehabilitation of Sheriff Dam’s Spillway

The Dam Safety Branch of the Colorado Division of Water Resources (DWR) has developed risk-based guidelines that have the potential to reduce dam rehabilitation scope and costs considerably in appropriate situations. This paper will cover how W. W. Wheeler & Associates, Inc. (Wheeler) used various DWR guidelines and worked with the DWR to reduce the cost and scope of the Sheriff Reservoir Dam Rehabilitation Project. The dam rehabilitation was optimized by identifying a risk-based spillway design which could provide adequate flood protection without being oversized, resulting in a cost savings of millions of dollars to the dam owner and reduced impacts to Forest Service land.