Safety of Idaho Rural Highways Under 129K Trucks

A significant number of local highway jurisdictions in Idaho lack the engineering expertise and financial resources to conduct detailed assessments when requests are received to increase weight allowances for local roadways beyond the current legal limit for gross load weight of 80,000 pounds. Idaho Code 49-1004A (1) states “the authority having jurisdiction may designate routes … for vehicles not exceeding … 129,000 pounds, utilizing criteria established by the board based upon road and bridge structural integrity and engineering standards” These higher load limits can enable private freight organizations to better compete in domestic and global markets by allowing them to distribute freight more efficiently. The Idaho Transportation Department has the engineering staff and database resources available to evaluate road and bridge capacities on state and federal highways; however, local highway districts may not have such resources. This limits the local districts’ ability to expeditiously consider increased load requests, which in turn limits freight organizations’ ability to operate more efficiently on rural highways resulting in less competitive Idaho industries. Additionally, many local roadways are not designed or constructed to accommodate any type of heavy load. This collaborative study between the Idaho Transportation Department and the Local Highway Technical Assistance Council would provide local highway jurisdictions guidance for conducting roadway assessment from review of available data and current condition to full engineering studies where appropriate.


  • English


  • Status: Completed
  • Funding: $25000
  • Contract Numbers:


  • Sponsor Organizations:

    Pacific Northwest Transportation Consortium

    University of Washington
    More Hall Room 112
    Seattle, WA  United States  98195-2700

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    University of Idaho, Moscow

    Department of Civil Engineering
    P.O. Box 441022
    Moscow, ID  United States  83844-1022
  • Project Managers:

    Ibrahim, Ahmed

  • Performing Organizations:

    University of Idaho, Moscow

    Department of Civil Engineering
    P.O. Box 441022
    Moscow, ID  United States  83844-1022
  • Principal Investigators:

    Ibrahim, Ahmed

  • Start Date: 20161215
  • Expected Completion Date: 20180131
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers
  • Subprogram: Rural Highways Load
  • Source Data:

Subject/Index Terms

Filing Info

  • Accession Number: 01632769
  • Record Type: Research project
  • Source Agency: Pacific Northwest Transportation Consortium
  • Contract Numbers: DTRT13-G-UTC40
  • Files: UTC, RiP
  • Created Date: Apr 27 2017 3:35PM