Transportation

Model Documentation

COG/TPB staff develops, maintains, and improves, 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 for 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. The TPB regional travel demand model is generally given a version number, which may have three parts: X.Y.Z. The first number represents major changes to the model. The second number represents more modest updates to the model. And the third number, sometimes called "build" is used to indicate smaller changes to the model, including bug fixes.

Currently Adopted Travel Model

The currently adopted, production-use regional travel demand model for the Washington, D.C. metropolitan area is known as the Version 2.3.70 Travel Demand Model. This model became the adopted, production-use model on Oct. 18, 2017, when the TPB adopted the following two resolutions:

  • R3-2018: Resolution finding that the Virginia Department of Transportation (VDOT) and the Maryland Department of Transportation (MDOT) off-cycle amendment to the 2016 Constrained Long-Range Plan conforms with the requirements of the Clean Air Act Amendments of 1990

  • R4-2018: Resolution approving the Virginia Department of Transportation (VDOT) and the Maryland Department of Transportation (MDOT) off-cycle amendment to the 2016 Constrained Long-Range Plan for the National Capital Region.

The Ver. 2.3.70 model is the latest in a series of adopted, regional, production-use travel demand models, within the “Version 2.3” model family. The previous adopted, regional, production-use travel demand model was the Ver. 2.3.66 model. All the model versions in the Version 2.3 model family are aggregate, trip-based, four-step travel demand models.

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 Ver.2.3.52. The model validation effort was documented in the following memo:

The user's guide for the current model, Ver.2.3.70, is in two volumes, one for the main report (including Appendix A) and one for Appendices B, C & D.

It is planned that the network documentation will be completed in March 2018.

The current developmental model is a trip-based travel demand model, known as the Ver. 2.5 travel model. It was developed in FY 17 by a consultant (Cambridge Systematics, Inc., and Gallop Corporation. FY 17 Task Orders. Final Report. Metropolitan Washington Council of Governments, National Capital Region Transportation Planning Board, June 2017) and is currently undergoing testing by TPB staff. Since it is a developmental model, it is not available for dissemination to outside parties.

Documentation for Past Adopted Travel Models

Version 2.3.66

Version 2.3.57a

Version 2.3.57

Version 2.3.52

  • User's Guide for the MWCOG/NCRTPB Travel Forecasting Model, Version 2.3, Build 52. Draft Report. 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). Metropolitan Washington Council of Governments, National Capital Region Transportation Planning Board, September 18, 2013.
  • 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. 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. 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. 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

 

Page updated 12/15/2017.