The mission of USACE is broad, and within the scope of that broad mission, information about watershed and channel behavior must be available for decision making for planning, designing, operating, permitting, and regulating. This chapter identifies studies for which such information is required, it describes conceptually the role that computer program HEC-HMS can play in providing that information, and it shows conceptually how HEC-HMS would be used to provide the information.
The pages below explain study scoping, data sources, method selection, model evaluation, and the role of companion software. They provide a current orientation for using the historical examples in the study chapters; the Preface explains how guidance notes and software tips identify later developments.