By the middle of the twentieth century, preservation efforts in the U.S. had become so prevalent, in number and among various locations, that it was necessary for the federal government to make legislation that would create programs and stronger means of advocacy. The National Historic Preservation Act (NHPA) was passed in 1966, creating government programs still in existence as well as the basis upon which all preservation legislation created since has been based.
NHPA changed preservation in the U.S. in several ways. First, it created several crucially important programs still in existence, the National Register of Historic Places and the Advisory Council on Historic Preservation. The National Register of Historic Places is a comprehensive survey of all historic sites, buildings, districts, objects, and structures deemed historically, architecturally, or archaeologically significant through an evaluative process, involving local, state, and federal preservationists. The Advisory Council on Historic Preservation oversees the Preserve America Program and the Section 106 process, wherein all projects receiving federal funding must be evaluated to determine their possible impacts on historic resources.
Second, in addition to the programs NHPA created, the legislation is important because it established the need for partnerships on local, state, and national levels. NHPA created State Historic Preservation Offices, or SHPOs, state offices in charge of designating and reviewing the historic resources in their respective states.
Finally, NHPA became the basis for several tax credit and incentive programs that encourage historic-building owners to preserve their buildings by providing financial assistance to make the projects’ costs competitively inexpensive with new construction.