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Truck Size and Weight

The Consolidated Appropriations Act, 2016, Truck Size and Weight Provisions

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Memorandum

Subject: Information: The Consolidated
Appropriations Act, 2016, Truck Size
and Weight Provisions		 Date: June 20, 2016
From: /s/Original signed by
Jeffrey A. Lindley
Associate Administrator for Operations		 In Reply Refer To: HOFM-1
To: Division Administrators in ID, KS, ME
and VT
Directors of Field Services
Director of Technical Services 		   

On December 18, 2015, the President signed into law the Consolidated Appropriations Act, 2016 (Act) (Pub. L. 114-113), making appropriations for the Federal Highway Administration, Highway Trust Fund, and other government agencies for the fiscal year ending September 30, 2016. This memorandum provides guidance on certain truck size and weight provisions of the Act. Those provisions, effective as of December 18, 2015, include: Vehicle weight limitations—Interstate System for Maine and Vermont (Division L, Sec. 124); Vehicle weight limitations—Interstate System for vehicles in Idaho (Division L, Sec. 124); and special rules for Kansas regarding property-carrying unit limitation (Division L, Sec. 137).

Division Offices should take notice that the truck size and weight provisions of the Act may affect these States' compliance with 23 CFR 650, Subpart C (National Bridge Inspection Standards). The potential impacts on bridge load rating and posting requirements are of particular importance. Division Offices should work with these four States to determine whether the Act's weight limit changes will require bridges to be re-rated and posted (restricted) with respect to the maximum load-carrying capacity in accordance with 23 CFR 650, Subpart C.

If you have any questions, please contact John Berg in the Office of Operations at 202-740-4602, or Lubin Gao in the Office of Infrastructure at 202-366-4604.

Attachment

A. BACKGROUND

Section 127 of title 23, United States Code (U.S.C.), establishes weight limitations for vehicles operating on the Interstate System. The maximum gross vehicle weight limitations are: 20,000 pounds on a single axle; 34,000 pounds on a tandem axle; or the maximum allowed by the Federal Bridge Formula (see "D." below), with an overall gross weight not to exceed 80,000 pounds, including all enforcement tolerances, except for those vehicles and loads which cannot be easily dismantled or divided, and have been issued permits in accordance with applicable State laws.

Section 31112 of title 49, U.S.C., establishes limitations with respect to the length of property-carrying units.

B. GOVERNING AUTHORITIES: The following are applicable to the Consolidated Appropriations Act, 2016 (Act) (Pub. Law 114-113) truck size and weight provisions:

  1. 23 U.S.C. 127 - Vehicle weight limitations - Interstate System
  2. 49 U.S.C. 31112 - Property-carrying unit limitation

C. DESCRIPTION OF THE CONSOLIDATED APPROPRIATIONS ACT, 2016, TRUCK SIZE AND WEIGHT PROVISIONS

Section 124 – Vehicle weight limitations—Interstate System

  • Maine and Vermont Vehicle Weight Limitations – Amends 23 U.S.C. 127(a)(11)(A) and (B) to make permanent certain provisions of Maine and Vermont state law.
    • With respect to all portions of the Interstate Highway System in the State of Maine, laws (including regulations) of that State concerning vehicle weight limitations applicable to other State highways shall be applicable in lieu of the requirements under 23 U.S.C. 127(a).
    • With respect to all portions of the Interstate Highway System in the State of Vermont, laws (including regulations) of that State concerning vehicle weight limitations applicable to other State highways shall be applicable in lieu of the requirements under 23 U.S.C. 127(a).
  • Vehicles in Idaho – Amends 23 U.S.C. 127 by adding the following provision specific to the State of Idaho: A vehicle limited or prohibited under 23 U.S.C. 127 from operating on a segment of the Interstate System in the State of Idaho may operate on such a segment if such vehicle: (1) has a gross vehicle weight of 129,000 pounds or less; (2) other than gross vehicle weight, complies with the single axle, tandem axle, and bridge formula limits set forth in 23 U.S.C. 127 (a); and (3) is authorized to operate on such segment under Idaho State law. See 23 U.S.C. 127(t).

Section 137 – Special rules for Kansas regarding property-carrying unit limitation
Kansas may now allow the operation of a truck tractor and 2 trailers or semitrailers not in actual lawful operation on a regular or periodic basis on June 1, 1991, if the length of the property-carrying units does not exceed 81 feet 6 inches and such combination is used only to transport equipment utilized by custom harvesters under contract to agricultural producers to harvest one or more of wheat, soybeans, and milo during the harvest months for such crops, as defined by the State of Kansas. See 49 U.S.C. 31112(c)(5).

D. TERMS AND DEFINITIONS

Federal Bridge Formula – Congress enacted the Bridge Formula in 1975 to limit the weight-to-length ratio of a vehicle crossing a bridge. This is accomplished either by spreading weight over additional axles or by increasing the distance between axles.

Compliance with Bridge Formula weight limits is determined by using the following formula:

Federal Bridge Formula W = the overall gross weight on any group of two or more consecutive axles to the nearest 500 pounds.; L = the distance in feet between the outer axles of any group of two or more consecutive axles; and N = the number of axles in the group under consideration.

where W = the overall gross weight on any group of two or more consecutive axles to the nearest 500 pounds.; L = the distance in feet between the outer axles of any group of two or more consecutive axles; and N = the number of axles in the group under consideration. 23 U.S.C. 127(a)(2).

Property-Carrying Unit – Any part of a commercial motor vehicle combination (except the truck tractor) used to carry property, including a trailer, a semitrailer, or the property-carrying section of a single unit truck. 49 U.S.C. 31112(a)(1).

Property-Carrying Unit Length – The length of the property-carrying units of a commercial motor vehicle combination is the length measured from the front of the first property-carrying unit to the rear of the last property-carrying unit. 49 U.S.C. 31112(a)(2).

Single Axle Weight – The total weight transmitted to the road by all wheels whose centers may be included between two parallel transverse vertical planes 40 inches apart, extending across the full width of the vehicle. The Federal single axle weight limit on the Interstate System is 20,000 pounds. 23 U.S.C. 127(a)(1).

Tandem Axle Weight – The total weight transmitted to the road by two or more consecutive axles whose centers may be included between parallel transverse vertical planes spaced more than 40 inches and not more than 96 inches apart, extending across the full width of the vehicle. The Federal tandem axle weight limit on the Interstate System is 34,000 pounds. 23 U.S.C. 127(a)(1).

Tractor or Truck Tractor – The non-cargo carrying power unit that operates in combination with a semitrailer or trailer, except for automobile transporters and dromedaries. See in 49 U.S.C. 31111(a) and 49 CFR 177.835.

E. QUESTIONS AND ANSWERS

Vehicle weight limitations for Maine, Vermont, and Idaho—Interstate System (Section 124)

Question 1: What changes did the Consolidated Appropriation Act, 2016 (Act) make to Interstate weight limits in Maine and Vermont?

Answer 1: Prior to the enactment of the Act, laws (including regulations) of the States of Maine and Vermont concerning vehicle weight limitations applicable to other State highways were applicable to the Interstate System in lieu of the 23 U.S.C. 127 requirements through December 31, 2031. The Act made the applicability of the State limitations permanent.

Question 2: Are the Federal Interstate vehicle weight limits in 23 U.S.C. 127, such as 80,000 pounds Gross Vehicle Weight, 20,000 pounds on single axle, 34,000 pounds on a tandem axle, and the Federal Bridge Formula, applicable in the States of Maine and Vermont?

Answer 2: No. Laws (including regulations) of Maine and Vermont concerning vehicle weight limitations applicable to other State highways are applicable to the Interstate System in those States in lieu of the Federal vehicle weight limits specified in 23 U.S.C. 127(a).

Question 3: Does the Federal Bridge Formula apply to a vehicle that weighs up to 129,000 pounds that is operating on the Interstate System in Idaho?

Answer 3: Yes. Under 23 U.S.C. 127(t)(2), such vehicle must comply with the single axle, tandem axle, and the bridge formula limits set forth in 23 U.S.C. 127(a).

Question 4: Aside from the axle and bridge formula limits, are there other conditions that must be met for a vehicle with a gross vehicle weight of up to 129,000 pounds to be able to operate on a segment of the Interstate System in the State of Idaho?

Answer 4: Yes. Under 23 U.S.C. 127(t)(3), such vehicle must also be authorized to operate on such a segment under Idaho State law.

Question 5: How does the Idaho provision impact bridge rating and posting requirements?

Answer 5: Bridges subject to the new legal loads in Idaho as a result of this provision must be rated and posted or restricted if necessary for these new legal loads to comply with 23 CFR 650, Subpart C.

Question 6: What are the Federal reasonable access requirements for a vehicle that weighs up to 129,000 pounds while operating on the Interstate System in the State of Idaho?

Answer 6: In accordance with 23 U.S.C. 127(b), the State may not enact or enforce any law denying reasonable access to motor vehicles subject to title 23, U.S.C., to and from the Interstate Highway System to terminals and facilities for food, fuel, repairs, and rest.

Special rules for Kansas regarding property-carrying unit limitation (Section 137)

Question 1: In Kansas, what is the allowable length limit of a truck tractor and 2 trailers or semitrailers not in actual lawful operation on a regular or periodic basis on June 1, 1991, if such combinations are used only to transport equipment utilized by custom harvesters under contract to agricultural producers to harvest one or more of wheat, soybeans and milo during the harvest months for such crops, as defined by the relevant State.

Answer 1: The State of Kansas may allow a length limit of up to 81 feet 6 inches for these vehicles.

Question 2: What actions should Kansas consider in implementing this provision?

Answer 2: As applicable, Kansas should revise State laws or regulations concerning lengths and backhaul in implementing this provision.

General

Question 1: When do the new provisions in the Act take effect?

Answer 2: The effective date for the Act is December 18, 2015. However, in Idaho, for the Federal law under 23 U.S.C. 127(t) to be in effect, a State law authorizing vehicles with gross vehicle weight of up to 129,000 pounds must also be in effect.

Question 2: Who may I contact for more information on these provisions?

Answer 2: Implementation guidance not covered in this memo should be directed to the FHWA Division Office Truck Size and Weight Specialist in Maine, Vermont, Kansas, or Idaho, as appropriate. A list of FHWA Division Office Truck Size and Weight Specialists is available at https://ops.fhwa.dot.gov/freight/sw/contact/index.htm#fhwa.

Question 3: Where are resources available for Vehicle Size and Weight?

Answer 3: FHWA has numerous resources available at https://ops.fhwa.dot.gov/freight/sw/index.htm.
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