Highway Ranking Model

New software to rank all proposed highway projects in a transportation plan based on gridlock relief has been developed by the Virginia Department of Transportation (VDOT), Northern Virginia District. The model uses the local metropolitan planning organization (MPO) future networks and future trip tables to process the data. It develops thousands of alternative highway networks using various combinations of planned highway improvements and then calculates the amount of gridlock relief for each improvement to develop the best sequence for constructing the plan to achieve the most gridlock relief per cost possible as improvement funds become available. The advantage of ranking all improvement projects with a computer model is to make sure limited resources are used to add capacity when and where it is most effective. Project A and Project B might both be excellent improvements by themselves in 2010, but if Project B goes first, then Project A may not reduce congestion any further on the regional system until post 2030. This model and the TTI model that is famous for ranking the Washington region as the third most congested area in the country produce similar results for this region. The model is debugged and has been used in production to rank 52 elements as potential candidates for a future Six Year Plan for Northern Virginia. To do this, the model ran for six days non-stop on a PC with Intel 3.06 GHz processor and 1.5 GB of RAM. The final output, after evaluating each improvement independently and in combination with other improvements, was a ranking of all the improvements to reduce the most gridlock in the 2010 time period. This was used to aid decision makers in developing the next Six Year Plan. Gridlock relief is measured in two ways by the model: vehicle miles of travel gridlock reductions per cost; and vehicle hours of delay reductions per cost. Gridlock relief is only measured if the Level of Service (LOS) passes a threshold, which is user specified, like LOS D, E or F. The model currently does not compare benefits across modes. It assumes planned transit improvements are in place for any forecast year highway ranking analysis. Transit networks may be incorporated in future versions of the model.


  • English

Media Info

  • Media Type: CD-ROM
  • Features: Tables;
  • Pagination: 6p
  • Monograph Title: Tools of the Trade: 10th National Conference on Transportation Planning for Small and Medium-Sized Communities

Subject/Index Terms

Filing Info

  • Accession Number: 01044609
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Mar 23 2007 12:08PM