A new theoretical approach to assessing the economic feasibility of sediment management strategies is proposed by incorporating probability distribution directly into the analysis. This would allow the life of Dez hydropower, for instance, to be prolonged definitely. The discount rate is also examined as a fundamental means of reflecting risk in discounted cash flow evaluations. Eight options for sediment management in Dez reservoir are assessed and future reservoir storage volumes estimated for the period 2018 to 2068. As a second step, discounted cash flow (DCF) with gamma discounting rate is used to evaluate present values for future cash flows for each option. The results indicate that these models, which offer an efficient approach, can be used to assess the cost-benefit feasibility of sediment management strategies. Guidelines are given for applying this approach to other projects.