To ensure that the National Network remains substantially intact, FHWA retains the authority to rule upon all requested additions to and deletions from the National Network as well as requests for the imposition of certain restrictions. FHWA approval or disapproval will constitute the final decision of the U.S. Department of Transportation.

(a) Additions. (1) Requests for additions to the National Network, including justification, shall have the endorsement of the Governor or the Governor's authorized representative, and be submitted in writing to the appropriate FHWA Division Office. Proposals for addition of routes to the National Network shall be accompanied by an analysis of suitability based on the criteria in § 658.9.

(2) Proposals for additions that meet the criteria of § 658.9 and have the endorsement of the Governor or the Governor's authorized representative will be published in the Federal Register for public comment as a notice of proposed rulemaking (NPRM), and if found acceptable, as a final rule.

(b) Deletions—Federal-aid primary—other than interstate. Changed conditions or additional information may require the deletion of a designated route or a portion thereof. The deletion of any route or route segment shall require FHWA approval. Requests for deletion of routes from the National Network, including the reason(s) for the deletion, shall be submitted in writing to the appropriate FHWA Division Office. These requests shall be assessed on the basis of the criteria of § 658.9. FHWA proposed deletions will be published in the Federal Register as a Notice of Proposed Rulemaking (NPRM).

(c) Requests for deletion—Federal-aid primary—other than interstate. Requests for deletion should include the following information, where appropriate:

(1) Did the route segment prior to designation carry combination vehicles or 102-inch buses?

(2) Were truck restrictions in effect on the segment on January 6, 1983? If so, what types of restrictions?

(3) What is the safety record of the segment, including current or anticipated safety problems? Specifically, is the route experiencing above normal accident rates and/or accident severities? Does analysis of the accident problem indicate that the addition of larger trucks have aggravated existing accident problems?

(4) What are the geometric, structural or traffic operations features that might preclude safe, efficient operation? Specifically describe lane widths, sight distance, severity and length of grades, horizontal curvature, shoulder width, narrow bridges, bridge clearances and load limits, traffic volumes and vehicle mix, intersection geometrics and vulnerability of roadside hardware.

(5) Is there a reasonable alternate route available?

(6) Are there operational restrictions that might be implemented in lieu of deletion?

(d) Deletions and use restrictions—Federal-aid interstate. (1) The deletion of, or imposition of use restrictions on, any specific segment of the Interstate Highway System on the National Network, except as otherwise provided in this part, must be approved by the FHWA. Such action will be initiated on the FHWA's own initiative or on the request of the Governor or the Governor's authorized representative of the State in which the Interstate segment is located. Requests from the Governor or the Governor's authorized representative shall be submitted along with justification for the deletion or restriction, in writing, to the appropriate FHWA Division Office for transmittal to Washington Headquarters.

(2) The justification accompanying a request shall be based on the following:

(i) Analysis of evidence of safety problems supporting the deletion or restriction as identified in § 658.11(c).

(ii) Analysis of the impact on interstate commerce.

(iii) Analysis and recommendation of any alternative routes that can safely accommodate commercial motor vehicles of the dimensions and configurations described in §§ 658.13 and 658.15 and serve the area in which such segment is located.

(iv) Evidence of consultation with the local governments in which the segment is located as well as the Governor or the Governor's authorized representative of any adjacent State that might be directly affected by such a deletion or restriction.

(3) Actions to ban all commercial vehicles on portions of the Interstate System not excepted under § 658.11(f) are considered deletions subject to the requirements of subsection (d) of this section.

(4) Reasonable restrictions on the use of Interstate routes on the National Network by STAA-authorized vehicles related to specific travel lanes of multi-lane facilities, construction zones, adverse weather conditions or structural or clearance deficiencies are not subject to the requirements of paragraph (d) of this section.

(5) Proposed deletions or restrictions will be published in the Federal Register as an NPRM, except in the case of an emergency deletion as prescribed in § 658.11(e). The FHWA will consider the factors set out in paragraph (d)(2) of this section and the comments of interested parties. Any approval of deletion or restriction will be published as a final rule. A deletion of or restriction on a segment for reasons ascribable to dimensions of commercial motor vehicles described in either § 658.13 or § 658.15 shall result in a deletion or restriction for the purposes of both §§ 658.13 and 658.15.

(e) Emergency deletions. FHWA has the authority to delete any route from the National Network, on an emergency basis, for safety considerations. Emergency deletions are not considered final, and will be published in the Federal Register for notice and comment.

(f) Exceptions. Those portions of the Interstate System which were open to traffic and on which all commercial motor vehicles were banned on January 6, 1983, are not included in the National Network.

(g) Restrictions—Federal-aid primary—other than interstate. (1) Reasonable restrictions on the use of non-Interstate Federal-aid Primary routes on the National Network by STAA-authorized vehicles may be imposed during certain peak hours of travel or on specific travel lanes of multi-lane facilities. Restrictions related to construction zones, seasonal operation, adverse weather conditions or structural or clearance deficiencies may be imposed.

(2) All restrictions on the use of the National Network based on hours of use by vehicles authorized by the STAA require prior FHWA approval. Requests for such restrictions on the National Network shall be submitted in writing to the appropriate FHWA Division Office. Approval of requests for restrictions will be contingent on the ability to justify significant negative impact on safety, the environment and/or operational efficiency.