Estimating the Net Social Benefits of Vehicle Trip Reductions with TRIMMS Model

Transportation demand management (TDM) programs struggle to prove a cost-effective and alternative means to address congestion and emission pollution reduction, while at the same time guarantying economic sustainability. There is a lack of standardized methods to quantify cost and benefits which represent a key impediment to effective TDM promotion. To assess this issue, the Center for Transit Research (NCTR) at the Center for Urban Transportation Research (CUTR), recently developed TRIMMS© (Trip Reduction Impacts for Mobility Management Strategies), a practitioner-oriented sketch planning tool. TRIMMS© estimates a wide range of benefits which highlight TDM effectiveness in reducing congestion, excessive fossil fuel consumption, emission pollution, and global climate warming, while considering economic efficiency and sustainability. The model provides default parameters for 85 metropolitan statistical areas, allows input customization and differentiates between analysis at the regional and employer-site levels. Recognizing that there is uncertainty in the value of inputs , TRIMMS© includes a Monte Carlo-based sensitivity analysis module. This feature allows estimating the probability that program benefit-to-cost ratios will at least be greater than some predetermined benchmarking value. This feature allows conducting TDM evaluation to meet the Federal Highway Administration Congestion and Air Quality (CMAQ) Improvement Program requirements for program effectiveness assessment and benchmarking.


  • English

Media Info

  • Media Type: DVD
  • Features: Figures; Maps; References; Tables;
  • Pagination: 21p
  • Monograph Title: TRB 89th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

Filing Info

  • Accession Number: 01156932
  • Record Type: Publication
  • Report/Paper Numbers: 10-3516
  • Files: TRIS, TRB
  • Created Date: Jan 25 2010 11:47AM