市區更新
Urban renewal programs are funded in part by federal grants. The National Historic Preservation Act of 1966, which created the NRHP, requires that federal agencies give consideration to the opinions of the Advisory Council on Historic Preservation in assessing the impact their actions will have on listed properties and consider alternatives to any action that would destroy or significantly affect them. The listings of downtown Troy's districts and buildings therefore had the practical effect of preventing their demolition for urban renewal.