Applying Risk-Benefit Analysis to Select an Appropriate Streambank Stabilization Measure

Stream stabilization designers are often faced with the challenge of selecting effective bank stabilization measures. The potential benefits of stream stabilization measures can be economic, environmental, or social. Depending on the level of the potential benefit, a designer may be willing to take higher risks in implementing a given measure. A risk-benefit analysis is presented here that involves a qualitative analysis of risk and benefit (using failure modes and effects analysis) and risk and benefit quantification in terms of cost. The initial result of the method is the establishment of risk priority numbers (RPN_s) and benefit priority numbers (BPN_s), which provide a relative qualitative measure of the potential risk and benefit and can be used to prioritize and rank measures. The results of the qualitative analysis are then used to estimate risk and benefit quantitatively in terms of cost. These quantitative values are then compared for several stabilization alternatives to provide justification and guidance on selecting the most effective alternative. The risk-benefit method is applied to select a stream stabilization measure for a stream rehabilitation project in Indiana.