Impacts of Risk-Based Analysis on Current Design Practices

A summary of hydrologic design standards used by selected federal agencies for the safety evaluation of dams is presented. A computational procedure is outlined to develop hydrologic design bases for dams and spillways using a risk-based methodology. Two illustrative examples are presented to demonstrate the impact of risk-based analysis on current design practices. it is shown that the hydrological design basis resulting from a risk-based analysis may not always be in conformity with applicable federal or state regulations. Finally, some of the limitations to the performance of an accurate risk-based analysis are presented.