The Hydrogeomorphic (HGM) Approach is a collection of concepts and methods for developing functional indices and subsequently using them to assess the capacity of a wetland to perform functions relative to similar wetlands in a region. The Approach was initially designed to be used in the context of the Clean Water Act Section 404 Regulatory Program permit review sequence to consider alternatives, minimize impacts, assess unavoidable project impacts, determine mitigation

of FWS for many years of interesting and helpful interaction. Mr. Lee Baxter, U.S. Bureau of Reclamation, shared some examples of sensitivity analyses done with spreadsheets, and Mr. Jon Campbell, Wetlands Branch, wrote the spreadsheet presented in Figure 7-2. Dr. Mary Davis, Wetlands Branch, provided many useful comments on the manuscript.