Chittenden County Metropolitan Planning Organization (CCMPO) Travel Model Peer Review Report

Table of Contents

• Disclaimer
• Acknowledgements
• Report Organization
• Report Purpose
• Virtual Peer Review Forma
• 1.0 CCMPO Responsibilities
• 2.0 Regional Characteristics
• 3.0 Travel Demand Modeling at CCMPO.
• 4.0 Current CCMPO Mode
  • 4.1 Model Applications
  • 4.2 CCMPO Model Inputs and Model Components Peer Discussion
• 5.0 Technical Questions
• 6.0 CCMPO Modeling Priorities
  • 6.1 Short-Term Priorities
  • 6.2 Long-Term Priorities
• 7.0 Peer Review Panel Recommendations
  • 7.1 Short-Term Priorities
  • 7.2 Long-Term Priorities
  • 7.3 Virtual Peer Review Forma
• Appendix A List of Peer Review Panel Participants
• Appendix B Peer Review Panel Biographies
• Appendix C CCMPO TMIP Peer Review Application
• Appendix D Peer Review Panel Technical Questions
• Appendix E CCMPO Modeling Priorities

List of Figures

Figure 1: Chittenden County Transportation System Map

List of Tables

Table 1: Chittenden County 2008 Employment by Industry

Disclaimer

The views expressed in this document do not represent the opinions of FHWA and do not constitute an endorsement, recommendation or specification by FHWA. The document is based solely on the discussions that took place during the peer review sessions and supporting technical documentation provided by the peer review host agency.

Acknowledgements

The FHWA wishes to acknowledge and thank the peer review panel members for volunteering their time to participate in the peer review of the Chittenden County Metropolitan Planning Organization (CCMPO) travel demand model and for sharing their valuable experience.

The Peer Review Panel Members were:

Rebekah Anderson (ODOT)
Kyung-Hwa Kim (ARC)
MaryAnn Waldinger (COMPASS)
Richard Walker (Portland Metro)

Brief biographies for each of the peer review panel members are presented in Appendix B.

Report Organization

This report is organized into the following sections:

• Overview of the purpose of this report, including an introduction to the peer review process and the objectives of the CCMPO peer review;
• Planning responsibilities of CCMPO;
• Introduction to the demographics, land use and transportation characteristics of the CCMPO region;
• A brief history of travel demand modeling at CCMPO;
• Discussion of how the CCMPO travel demand model is used and a review of model inputs and each component of the CCMPO model. This section includes the majority of the discussion that took place during the peer review;
• Additional discussion of future enhancements to the CCMPO model; and
• Peer review panel recommendations.

In addition to the main body of the report, there are five appendices. Appendix A is a list of peer review participants. Appendix B contains brief biographies for each of the peer review panel members. Appendix C is the TMIP peer review application submitted to FHWA by CCMPO. Appendix D is a list of technical questions about the travel model submitted by the panel. And Appendix E is a list of short-term and long-term modeling priorities developed by CCMPO.

Report Purpose

This report summarizes the results of a peer review of the CCMPO travel demand model. The peer review was supported by the Travel Model Improvement Program (TMIP), which is sponsored by FHWA. The peer review of a travel model can serve multiple purposes, including identification of model deficiencies, recommendations for model enhancements, and guidance on model applications. Given the increasing complexities of travel demand forecasting practice and the growing demands by decision-makers for information about policy alternatives, it is essential that travel demand forecasting practitioners have the opportunity to share experiences and insights. The TMIP-supported peer review provides a forum for this knowledge exchange.

CCMPO applied for the peer review to obtain a better understanding of their current models capabilities and to help address new travel demand modeling needs in their region. The CCMPO travel demand model was recently updated to a full daily model and was re-validated using newly acquired 2009 National Household Travel Survey (NHTS) add-on data. Informal peer reviews have been conducted in the past by local transportation planning and modeling professionals, but a review by practitioners with a broader range of experience was desired. The TMIP peer review provided an excellent means to assess CCMPO's existing model system and provide recommendations for our ongoing model updates in order to maximize limited resources. Of particular interest are suggestions related to multimodal modeling of mixed use centers in smaller urban areas and the potential advantages and difficulties associated with moving to an activity-based modeling system.

The peer review was convened to provide guidance to CCMPO so that its travel demand model can meet the ever growing list of challenges. The primary goals of this peer review were to:

1. Identify techniques for modeling mixed housing and employment land use areas which are designed to support additional non-motorized and transit use.
2. Identify procedures for improving air quality and climate change modeling.
3. Prioritize areas for inclusion if the model geography were to expand outside the county boundary.
4. Elicit recommendations regarding the general interaction between regional models and microsimulation tools.
5. Identify how the effects of increased travel costs (e.g. gas prices) can be better implemented in the model.
6. Identify possible refinements to the FHWA Quick Response Freight Manual techniques for representing light, medium, and heavy truck freight in the regional model.
7. Discuss the considerations associated with the transitioning into an activity-based or tour-based model.
8. Elicit recommendations regarding land use forecasting tools, including the existing Land Use Allocation Module (LUAM) included in CCMPO's current model.
9. Elicit recommendations on visualization techniques and performance measures for better communication to stakeholders.
10. Discuss additional improvements CCMPO should consider to maintain a model consistent with current best practices.

Virtual Peer Review Format

The format for the CCMPO Peer Review was a bit different than typical TMIP Peer Reviews. Standard practice is to hold a one to two day in-person on-site meeting at the agency's offices thereby requiring travel by the invited panel members.

The meeting agenda is usually broken into two main parts. First, the agency presents and discusses the organization's responsibilities, characteristics, and planning objectives followed by a detailed overview of the existing regional travel demand model. Second, the panel then typically meets independently to formalize their recommendations which are presented and discussed with the agency and meeting participants prior to concluding the peer review.

CCMPO staff was mindful of the resources and scheduling difficulties associated with an in-person peer review process. To that end, the agency proposed initiating a 'virtual' peer review which was completed over the course of four online webinar sessions. The intent was to remove potential barriers to participation for panelists, decrease costs, and still provide thoughtful reviews to assist in determining future model investments.

Four separate roughly two-hour meetings were held via web-conference. The meetings were organized and hosted by FHWA with support from the Volpe Center which also recorded the audio portion of the meetings. Each meeting session is described below.

Session #1

Date: February 15, 2011, 2pm - 4pm EST

Agenda: Introductions, background, review of existing model, potential improvements

Session #2

Date: March 1, 2011, 1:00 - 3:30pm EST

Agenda: Discussion of key issues and questions, areas for improvement

Session #3

Date: April 8, 2011, 3:00 - 4:30pm EST

Agenda: Independent panel meeting convened to assemble comments and feedback

Session #4

Date: April 12, 2011, 2:00 - 4:00pm EST

Agenda: Comments and feedback presented by peer review panel to broader group