Toll Demand Model for the Delaware Department of Transportation Travel Demand Model

As transportation providers across the nation face growing funding shortfalls, they are increasingly looking to tolling as an option to increase revenue. As toll revenue becomes a more important part of the funding for transportation programs, agencies are seeking to determine the potential impacts of more complex arrays of tolling options such as electronic toll collection and frequency-of-use discounts. The transportation planning organizations responsible for providing information to agencies are being expected to produce more reliable forecasts of traffic and revenue that directly reflect the subtleties of these tolling scenarios. To provide this information, the Delaware Department of Transportation (DelDOT) developed an improved toll demand model. This toll demand model was incorporated into the existing nested logit mode choice model. One thing that makes the new toll demand model unique is that it not only incorporates the toll–no-toll choice but also includes an E-ZPass ownership model used for cash–E-ZPass market segmentation. The model allows DelDOT to reduce the amount of “unquantifiable” attributes included in the mode choice bias constants. The model would be readily transferable to other areas that either do not currently have tolling or do not explicitly account for tolling in their existing models.