Transportation

Model Documentation

COG/TPB staff develops and maintains, with some consultant assistance, a series of regional travel demand models that are used for the regional transportation planning process in the Washington, D.C. metropolitan area. These regional travel demand models are developed under the guidance of the Travel Forecasting Subcommittee (TFS), which is a subcommittee of TPB's Technical Committee. At any given time, the COG/TPB staff maintains at least two regional travel demand models: an adopted, production-use model and a developmental model. The production-use model is the one that is used planning studies conducted by COG/TPB and is made available to outside parties for their use. The developmental model is the one that is currently under development by COG/TPB staff, and is generally not made available to outside parties. Each major change or revision to the model is referred to as a "build"; and is often indicated as the third index in the model version number, e.g., build X of the Version 2.3 Travel Model can be called Version 2.3.X.

Currently Adopted Travel Model

The currently adopted, production-use regional travel model for the Washington, D.C. metropolitan area is the TPB Version 2.3 Travel Model, Build 66, also known as the Version 2.3.66 Travel Model. This model became the adopted travel model on November 16, 2016, when the TPB adopted the following two resolutions:

  • R3-2017: Resolution finding that the 2016 Constrained, Long-Range Plan Amendment and the FY 2017-2022 Transportation Improvement Program conform with the requirements of the Clean Air Act Amendments of 1990, as represented by the state air quality implementation plans (SIPs);
  • R4-2017: Resolution approving of the 2016 Amendment to the Constrained, Long-Range Transportation Plan for the National Capital Region.

The TPB Version 2.3 Travel Model was calibrated to year-2007 conditions in 2012, and this work was documented in the following calibration report:

In 2013, the Version 2.3 Travel Model was validated to year-2010 conditions. Updates to the model resulting from this validation work were part of Build 52. The model validation effort was documented in the following memo:

The user's guide for the current model, Ver.2.3.66, is in two volumes, one for the main report (including Appendix A) and one for Appendices B, C & D.

The current documentation for the highway and transit networks used by the regional travel demand model is currently being written.

Documentation for Past Adopted Travel Models

Version 2.3 (Build 57a)

Version 2.3 (Build 57)

Version 2.3 (Build 52)

  • Milone, Moran, Humeida, Seifu, and Martchouk. User's Guide for the MWCOG/NCRTPB Travel Forecasting Model, Version 2.3, Build 52. Draft Report. Washington, D.C.: Metropolitan Washington Council of Governments, National Capital Region Transportation Planning Board, September 18, 2013.
  • User's Guide for the MWCOG/NCRTPB Travel Forecasting Model, Version 2.3, Build 52: Appendices B (Batch Files), C (Cube Voyager Scripts), and D (AEMS Fortran Control Files). Washington, D.C.: Metropolitan Washington Council of Governments, National Capital Region Transportation Planning Board, September 18, 2013.
  • Milone, Seifu, Yin, Moran, Hamlin, Davis, Posey, and Bacon. Highway and Transit Networks for the Version 2.3.52 Travel Model, Based on the 2013 CLRP and FY 2013-2018 TIP. Final Report. Washington, D.C.: Metropolitan Washington Council of Governments, National Capital Region Transportation Planning Board, March 18, 2014.

Version 2.3 (Builds 33 through 39)

  • Calibration Report for the TPB Travel Forecasting Model, Version 2.3, on the 3,722-Zone Area System. Final Report. Washington, D.C.: National Capital Region Transportation Planning Board, January 20, 2012.
  • User's Guide for the TPB Travel Forecasting Model, Version 2.3, Build 38, on the 3,722-Zone Area System. Final Report. Washington, D.C.: National Capital Region Transportation Planning Board, January 20, 2012.
  • Snead, Milone, Hamlin, Davis, Seifu, and Martchouk. FY-2010 Network Documentation: Highway and Transit Network Development. Draft. Washington, D.C.: National Capital Region Transportation Planning Board, June 30, 2010.

Version 2.2

  • COG/TPB Travel Forecasting Model Version 2.2 Specification, Validation, and User's Guide - March 1, 2008
  • Two-Step Traffic Assignment for HOT Lane Modeling in 2008 CLRP - December 2, 2008
  • Transmittal of Version 2.2 travel model files as per the 2008 CLRP/2009-2014 TIP air quality determination - December 17, 2008
  • TPB Models Development Status Report - presentation to the Travel Forecasting Subcommittee on November 21, 2008. Slides 6-11 discuss updates to the Version 2.2 travel model, including the two-step assignment.
  • FY-2008 Network Documentation: Highway and Transit Network Development- September 19, 2008.
  • FY-2009 Network Documentation: Highway and Transit Network Development. Draft report. June 30, 2009.

Version 2.1D

  • Status of the TPB Version 2.1D Regional Travel Model - September 17, 2004
  • COG/TPB Travel Forecasting Model Version 2.1 D Draft #50 Calibration Report - November 17, 2004
  • COG/TPB Travel Forecasting Model Version 2.1 D Draft #50 User's Guide - November 17, 2004
  • FY-2004 Network Documentation: Highway and Transit Network Development- November 17, 2004