Questions and Answers About Vehicle Size and Weight

23 CFR 658.11 Additions, deletions, exceptions, and restrictions (to National Network)

Can non-Interstate System designated routes be removed from the National Network?
Can Interstate System highway segments be removed from the National Network?
May States impose reasonable restrictions on the use of Interstate System routes without approval from the FHWA?
May States restrict use of the non-Interstate National Network routes by vehicles authorized to operate on those routes under Federal law and regulations without FHWA approval?
May States restrict the hours that vehicles subject to Federal size limits may use the National Network?
When the National Network was designated, some States included all Federal-aid primary highways on it without a specific designation. Are they part of the designated network?
May States restrict trucks to specific lanes on multi-lane highways?
What is FHWA’s recommended practice for closures of Interstate highway segments for Special Events?
What should the FHWA Division Office consider when consulting with the State on proposals to close Interstate highway segments for special events?

23 CFR 658.11 Additions, deletions, exceptions, and restrictions (to National Network)

Can non-Interstate System designated routes be removed from the National Network?

Yes, subject to approval by the FHWA. 23 CFR 658.11©

Can Interstate System highway segments be removed from the National Network?

Yes, subject to approval by the FHWA. 23 CFR 658.11(d)

May States impose reasonable restrictions on the use of Interstate System routes without approval from the FHWA?

Yes, when they are related to (1) specific travel lanes on multi-lane highways; (2) construction zones; (3) adverse weather conditions; or (4) structural or clearance deficiencies. 23 CFR 658.11(d)(4).

Construction zones may include restrictions to the mainline or ramp(s) of a long or short duration, and include all travel lanes, or specific travel lanes. Information on construction zone restrictions should be disseminated under established State and local procedures. Notice of the restrictions should be provided in advance to the public and to neighboring State and Local DOT's that are affected by the construction. Similar to the intent of 658.11, the Work Zone Safety and Mobility Rule and the associated Transportation Management Plan (TMP) provide a consultative process for the identification of effects on truck traffic caused by work zones and the means to minimize those effects such as detours and notification to the traveling public.

For more information, please see: http://www.ops.fhwa.dot.gov/wz/resources/final_rule.htm and 23 CFR Part 630.1002 to 630.1016.

May States restrict use of the non-Interstate National Network routes by vehicles authorized to operate on those routes under Federal law and regulations without FHWA approval?

Yes, on specific travel lanes of multi-lane highways, restrictions related to construction zones, seasonal operations, adverse weather conditions and structural or clearance deficiencies. 23 CFR 658.11(g).

May States restrict the hours that vehicles subject to Federal size limits may use the National Network?

Yes, subject to approval by the FHWA. 23 CFR 658.11(g)(2)

When the National Network was designated, some States included all Federal-aid primary highways on it without a specific designation. Are they part of the designated network?

Yes. The States' inclusion of them as part of the NN was an automatic designation.

May States restrict trucks to specific lanes on multi-lane highways?

Yes. There are no Federal traffic laws that require all highway lanes to be available to all types of commercial motor vehicles.

What is FHWA’s recommended practice for closures of Interstate highway segments for Special Events?

Due to potential impacts on interstate commerce, FHWA recommends that proposals to close segments of the Interstate System for special events be developed in consultation with the FHWA Division Office. The purpose of the Interstate System includes the safe and efficient transportation of persons and goods. Use of segments of the Interstate System for special events, which may disrupt traffic, impede commerce, or present a potential safety concern to the traveling public is discouraged.

States are responsible for activities occurring on the Interstate System, including approval of special events. Efforts should be made to minimize the closure of Interstate segments, disruption of traffic, and reasonable alternate routes should be provided. In addition, full consideration of the safe operation of detours and connecting facilities must be assured for commercial and passenger vehicles. Information about special event closures should be provided in advance to the public and to State and Local DOTs.

Additional information on Interstate System Access Guidance may be found at: https://www.fhwa.dot.gov/programadmin/fraccess.cfm.

What should the FHWA Division Office consider when consulting with the State on proposals to close Interstate highway segments for special events?

During consultation with the State, the FHWA Division should consider:
Impact on interstate commerce;
Potential safety concerns;
Alternative routes that can safely accommodate commercial motor vehicles of the dimensions and configurations described in sections 658.13 and 658.15;
Duration and location of the closure;
Level of coordination with the local governments in which the segment is located, and the Governor or the Governor's authorized representative of other State(s) that might be affected by such a closure;
The State’s plan for providing advance information to the public and to State DOTs.