“Assumption” of the federal Clean Water Act (CWA) Section 404 describes the process whereby a state or tribe obtains approval from the U.S. Environmental Protection Agency (EPA) to administer a § 404 program within their borders and consequently begins administering all aspects of the program. The process of Section 404 assumption is a complex one, requiring interested states and tribes to invest significant time and resources into exploring options, compiling a complete application and developing a robust assumed program at the state/tribal level. NAWM has developed a set of resources to inform and assist states and tribes that are considering assumption. Resources include assumption frequently asked questions (FAQ), a list of commonly used assumption terms and definitions, and tips and lessons learned from states that have worked on key components of the assumption process, including documenting assumable waters and conducting regulatory crosswalks. NAWM also provides a useful a checklist of considerations for states/tribes starting to explore assumption and a matrix of useful assumption resource examples that states and tribes can review and adapt.