Calculation method for multidimensional flood control benefits of embankments

Traditional methods for calculating embankment flood control benefits (FCBs) fail to fully consider multiple benefit categories and require repeated flood simulations and loss estimations. This study defines embankment FCB as encompassing economic, life, health, and environmental benefits, which arise from the embankment's mitigation of flood-induced economic losses, loss of life, health impacts, and environmental damage. By introducing the value of a statistical life (VSL), a monetary quantification method of loss of life is proposed. By analyzing the ratio of injuries to deaths and the ratio of value of statistical injury to VSL, a monetary quantification method for health impacts is proposed. Combined with the environmental loss rate and the monetary value of the environment, the monetary value of environmental impacts is calculated. Based on the monetized value of comprehensive flood losses, this study proposes a simplified frequency method that only requires flood simulations and loss calculations under no-project conditions. A case study is conducted to verify the method, and the results indicate that economic benefits hold an absolute advantage in the total FCB, but the life, health, and environmental benefits should never be overlooked. The method has broad application prospects in comprehensive benefit evaluation and benefit–cost analysis of embankments.