The Benefits of Achieving the Chesapeake Bay TMDLs (Total Maximum Daily Loads): A Scoping Study

Concerns about nutrient pollution in the Chesapeake Bay have led to the establishment of pollution limits—total maximum daily loads (TMDLs)—which, by 2025, are expected to reduce nitrogen loadings to the Bay by 25 percent and phosphorous loadings by 24 percent from current levels. This paper outlines how the benefits associated with achieving the Chesapeake Bay TMDLs could be measured and monetized. We summarize studies that measure the benefits of improved water quality in the Bay and evaluate whether these studies could be used to value the water quality benefits associated with the TMDLs.In cases where studies conducted in the Bay watershed either do not exist or are out of date, we discuss whether results from studies conducted elsewhere could be transferred to the Chesapeake Bay. We also discuss original studies that would be useful to conduct in the future.