NJTPA Update Blog

NJTPA staff hosted four webinars from mid-March to mid-April to hear from other MPOs around the country about their travel demand modeling experiences and approaches. The webinars were part of efforts by the NJTPA to consider upgrades to its computer model which is used to simulate the operation of the regionwide transportation system and to forecast and analyze travel patterns for required planning activities.

The webinars each featured two presenters from around the country. They allowed NJTPA and partner agency planners and technical staff to learn about using models to help answer questions facing the region — the impacts of emerging transportation technologies, changing demographics and behavior, new travel modes, and economic changes.

The NJTPA’s model currently uses traditional “trip-based” methods to predict where and when individuals travel for specific activities such as work, education or shopping. A more complex approach, “tour-based” modeling, is used by several of the agencies that presented in the webinars. This approach considers travel behavior in greater detail. It groups together trips into a tour, which reflects an individual’s travel from home to one or more destinations and then back home. In contrast, trip-based modelling does not associate various stops with the same individual. Some of the agencies also discussed “destination choice” models, which could improve accuracy as well.

Webinar participants also heard about useful online resources such as the OpenStreetMap, a collaborative online map built on the model of Wikipedia, and General Transit Feed Specification data which allows transit schedules to be compiled from various providers. These can help to better represent road, public transit, walking and biking trips.

In addition to assessing regional travel and air quality impacts, the NJTPA model is adapted by partner agencies and subregions for use in predicting local effects such as land use changes. Any upgrades to the NJTPA model would consider these functions. As highlighted in the webinars, added complexity would require more data, computing power and staff time, but could strengthen the ability of planners and policy makers to understand the choices and needs of the traveling public.
 
Webinar presenters included the New York Metropolitan Transportation Council and the Delaware Valley Regional Planning Commission; metropolitan planning organizations in Baltimore, Atlanta, San Francisco, Dallas/Fort Worth, Portland (Oregon), and Seattle; and the North Carolina DOT, which conducts modeling for Charlotte. Partners from NJTPA subregions, NJ TRANSIT, the New Jersey Department of Transportation, the Port Authority of NY and NJ, and Federal Highway Administration participated. The webinars were held on March 11th, March 23rd, April 8th and April 22nd.