Creating a Statewide Modeling System in Virginia

Presentation for the 11th TRB National Transportation Planning Applications ConferenceMay 7, 2007

Outline

• Overview of Modeling in Virginia

• Creating the Virginia Transportation Modeling (VTM) System

• Implementation of VTM System

• Lessons Learned

Travel Demand Modeling in Virginia: 1960-Early 1990’s

• 1960-1970’s: – Extensive Survey Work and several 3 and 4-step models created.

Models run on mainframe computers.

• 1980’s: – Models switched from Mainframe to MINUTP and TRANPLAN

software.

– Technical Transportation Planners wear many hats including Travel Demand Modeling

• Early 1990’s: – Decline in VDOT in house modeling capability as many technical

transportation planning staff knowledgeable about travel demand modeling move on to other jobs or retire.

– Modeling Needs begin to increase significantly.

Travel Demand Modeling in Virginia: Mid 1990’s – Early 2000’s

– Modeling Needs Continue to Increase• Air Quality Conformity

• Transit, Toll, and Freight

• Seven new models

• Number of Models maintained by VDOT more than doubles

– Number of VDOT Staff doing modeling work decreases

– Many problems with consultant led modeling projects

Travel Demand Modeling in Virginia: Early 2000’s - Present

• 2003: – Creation of New VDOT Central Office Modeling Group

• 2004: – Modeling Group begins work on VTM Modeling System

• 2005:– VTM Model User’s Group Created

• 2006: – VTM Modeling System Policy & Procedures Manual Completed

– Implementation of VTM Modeling System begins

– Most models moved to a common software platform and format: CUBE Voyager

• State/MPO Modeling Staff increase after several years of decline

• Modeling needs continue to increase

VDOT Central Office

Why Did VDOT Decide to Create a Statewide Model System?

• Efficiency Consistency Easier to Maintain and Train Quicker Turnaround on Model Requests

• Technically Defensible

• Move Towards Best Practice Large Model Regions: Advanced 4-Step Small Model Regions: Basic 3 or 4-Step Renewed focus on Project Level Forecasting

What type of Modeling System to Create?

How comprehensive should it be?

How high should standards be?

How standardized do models need to be?

How to balance needs between small and large urban areas?

How to make system flexible to handle future needs?

Development Process

• Initially: Limited Outreach– VDOT Central Office Modeling Staff

• Eventually: Collaborative Effort– VDOT Central Office Modeling Staff– VDOT Central Office Planning Staff– VDOT District Modeling Staff– VDOT District Planning Staff– Planning District Commissions– Metropolitan Planning Organizations– Creation of Virginia Transportation

Modeling (VTM) User’s Group

Virginia Transportation Modeling (VTM) System

Comprehensive Minimum Guidelines & Standards– All Urban Area models– Full Range of Travel Demand Modeling activities: Inputs to Analysis

Some Standardization– Software– Acceptable Procedures– File Names– Transportation Network Attributes

Higher Standards for Large vs. Small Model Regions

Acceptable vs. Recommended Practice

Maintain some Flexibility– Guidelines vs. Standards– Possible to go above and beyond minimum guidelines & standards

Existing Travel Demand Modeling Regions

Future Travel Demand Modeling Regions

Policies and Procedures Manual

Examples from Policy and Procedures Manual: TAZs

Policy and Procedures Manual: Mode Choice

Policy and Procedures Manual: Guidelines for Cutline Analysis

Policy and Procedures Manual: Dynamic Validation

Implementation Process

• Work in Progress: Improving Land Use Forecasting Process Moving all models to common software format: Citilabs

CUBE Voyager Catalogs Transportation Network Standardization Linking Transportation Networks with GIS and State

Traffic Databases

• Multi-year Effort Five Year Plan: FY 2007 – FY 2012

• Large Data Collection Efforts Planned NHTS Survey Add-Ons Statewide External Station Surveys

Lessons Learned

• It takes a Village Collaborative Effort Needed Partnership: VDOT, Planning District Commissions,

MPOs, and State Universities Extensive Outreach and Education about Travel Demand

Modeling Needed

• Rome was not built in a day Initial Efforts were too Ambitious Do not overextend Staff Resources Measuring Expectations

• Balancing Development vs. Application Needs Coordination with Air Quality Conformity schedules Coordination with CLRP and Corridor Study schedules

Questions?