This paper presents and defines a method for standardizing ecosystem services in the context of hydropower projects and demonstrates its applicability through the Folsom hydropower plant in California. In particular, this paper uses the Final Ecosystem Goods and Services Classification System (FEGS-CS) to provide a structured framework for identifying ecosystems, the potential services they provide, and their beneficiaries. In this paper, the benefit transfer technique is used for estimating non-market values for new policy contexts. The total value of this case study is about USD 169 million per year for the Folsom hydropower plant in California. The advantage of the proposed framework lies in its ability to be imported and applied to any other hydropower facility, and it can be extensively used both for new and existing power plants.