Rainbow Bridge -- Smith Ferry, Idaho

Cultural Resources

Cultural resource investigations involve documentation, interpretation, and preservation of prehistoric/historic archaeological sites, historic structures and traditional cultural properties that are evaluated as eligible for the National Historic Register. ITD’s policy is to either avoid adverse impacts to cultural resources or to minimize and mitigate the impacts for all projects requiring ground disturbance.

ITD is required by federal regulations in Section 106 of the National Historic Preservation Act (NHPA) of 1966 and Section 4(f) of the Department of Transportation Act of 1966, to assess the historic resources prior to potential impacts related to transportation construction and maintenance activities.

Section 106 Review Requires:

  1. Identification of historic properties that may be affected by the proposed transportation projects and resolves such conflicts
  2. Consulting with the State Historic Preservation Office (SHPO), the Tribal Preservation Offices (THPO), and other interested persons/parties during the early stages of planning and throughout the project
  3. Preparing cultural resource analysis describing each cultural resource, its specific location and potential impacts to it from the project
  4. Completing the “Determination of Significance and Effect” form (ITD-1502) with SHPO concurrence

Section 4(f) Evaluation Requires:

  1. Analysis of impacts to cultural resources on or eligible for the National Register of Historic Places (historic sites, bridges, archaeological resources) and impacts to public parks, recreation areas, and, wildlife and waterfowl refuges, resulting from transportation projects
  2. Identifying the resources being used by a project and examining alternatives to avoid that use

Additional information and guidance concerning Cultural Resources Investigations can be found at the following links:

Idaho State Historical Society
Environmental Process Manual
Federal Highway Administration (FHWA)
Advisory Council on Historic Preservation
Expedited Section 106 Review Using the Programmatic Agreement
Protecting Historic Properties: Citizen's Guide to Section 106 Review