Active transportation demand model for decision-making in Fredericton
University of New Brunswick
There has been an increase in demand for Active Transportation (AT) in urban areas, yet there is a lack of guidance incorporating AT in standard four-step travel demand modelling. This broad issue presented itself as an opportunity for this thesis: the development of a calibrated AT demand model to aid decision-making processes for a small city, followed by scenario testing to determine factors contributing to AT use. Fredericton, New Brunswick was used as a case study given the availability of multimodal bridge traffic counts and the ability to create a cordon area with the two bridges: one bridge with AT and road traffic, and the other with AT traffic only. These two bridges are very different when it comes to characteristics that might influence AT use including sounds levels, sidewalk width, and proximity to traffic. Once the model was completed in VISUM, then the calibration began and it was possible to calibrate AT volumes on the Bill Thorpe Walking Bridge to match existing demand; however, AT volumes on the Westmorland Street Bridge were consistently overestimated. This suggests that if AT users treated both bridges the same, there would be 1100 more users per day on the Westmorland Street Bridge. It was hypothesized that AT users were assigning a generalized cost penalty to the Westmorland Street Bridge, effectively making the route appear to be costlier than the actual physical distance. To reach all calibration target values, the AT link length was increased on the Westmorland Street Bridge 1.5km or four times the bridge link length to represent the penalty. Next steps consist of the inclusion of seasonal adjustment factors to better understand volumes crossing the bridges and different trends in different months.