23 CFR Appendix C to Subpart A of Part 470, Policy for the Signing and Numbering of Future Interstate Corridors Designated by Section 332 of the NHS Designation Act of 1995 or Designated Under 23 U.S.C. 103(c)(4)(B)
State transportation agencies are permitted to erect informational Interstate signs along a federally designated future Interstate corridor only after the specific route location has been established for the route to be constructed to Interstate design standards.
1. The corridor must have been designated a future part of the Interstate System under section 332(a)(2) of the NHS Designation Act of 1995 or 23 U.S.C. 103(c)(4)(B).
2. The specific route location to appropriate termini must have received Federal Highway (FHWA) environmental clearance. Where FHWA environmental clearance is not required or Interstate standards have been met, the route location must have been publicly announced by the State.
3. Numbering of future Interstate route segments must be coordinated with affected States and be approved by the American Association of State Highway and Transportation Officials and the FHWA at Headquarters. Short portions of a multistate corridor may require use of an interim 3-digit number.
4. The State shall coordinate the location and content of signing near the State line with the adjacent State.
5. Signing and other identification of a future Interstate route segment must not indicate, nor imply, that the route is on the Interstate System.
6. The FHWA Division Office must confirm in advance that the above conditions have been met and approve the general locations of signs.
1. Signs may not be used to give directions and should be away from directional signs, particularly at interchanges.
2. An Interstate shield may be located on a green informational sign of a few words. For example: Future Interstate Corridor or Future I-00 Corridor.
3. The Interstate shield may not include the word “Interstate.”
4. The FHWA Division Office must approve the signs as to design, wording, and detailed location.