Design

U.S. Department of Transportation Federal Highway Administration

MEMORANDUM

The Office of Infrastructure is pleased to distribute the Interstate System Access Informational Guide (.pdf, 1.1 mb). We ask that you share this information with your partner agencies including local agencies, metropolitan planning organizations, regional authorities, and turnpike and tollway authorities. The Guide along with FHWA's Interstate Access policy is available electronically at: https://www.fhwa.dot.gov/programadmin/interstate.cfm.

The purpose of the Guide is to identify successful practices and provide support for an informed and consistent decision-making process that considers the impacts of proposed changes in access to the Interstate System. The Guide therefore, supports the justification and documentation of the information necessary to substantiate FHWA's consideration and potential approval of any proposed change in access to the Interstate System. The organization and information contained in the Guide facilitates the consideration of the appropriate issues, conduct of the required analysis, and decision-making in a manner that considers and is consistent with the provisions of FHWA's Policy on Access to the Interstate System (74 FR 43743 (August 27, 2009)).

Notable changes incorporated into the Guide include the following:

• Interstate access requests are no longer required to include highway capacity and operational analysis in accordance with the Highway Capacity Manual if another traffic analysis method was selected, as being more appropriate, to fully identify and evaluate performance and impacts of the proposed access change. This guidance replaces the requirements in FHWA's memo dated August 21, 2001.
• Guidance clarifying FHWA's expectations regarding partial interchanges.
• Guidance clarifying transportation system management (TSM) alternatives and the analysis required.
• Identification of the requirement to document and verify the analysis conducted in support of proposed change in access was consistent with regional models and the preferred alternative included in the TIP, STIP, and LRTP.
• Identified a range of alternatives that may need to be considered to justify additional Interstate access and what would constitute a no-build alternative and
• Clarified the requirement that all changes in access must connect to a public road.

Additional technical resources and tools are also available on FHWA's web site at: https://www.fhwa.dot.gov/programadmin/fraccess.cfm and FHWA's internal Design Discipline Support Site. In the interest of continual process improvement and to support Divisions in their stewardship and oversight of the Interstate System, the Office of Program Administration will periodically update the Interstate System Access Informational Guide. Please submit recommended revisions or successful practices to consider in future updates to the document to either Brooke Struve (brooke.struve@dot.gov) or Michael Matzke (Michael.matzke@dot.gov).

• Traffic Analysis Tools