Exploring Strategies for Promoting Modal Shifts to Transitways

Transitways represent large public investments whose positive impacts must be maximized whenever possible to justify the expenditures they entail. Prominent among those looked-for positive impacts is the encouragement of automobile-to-transit mode shifts by attracting increased transitway ridership.

This study explores the impacts of travel time, travel cost, and population density on mode choice, using the 2010 Travel Behavior Inventory. We found a monetary value of in-vehicle travel time of $17.5/hour and a transfer penalty of $10, equivalent to 35 minutes in-vehicle travel time. Density, especially at destinations, has important effects, but travel time is the key to promote the shift to transit.

The research also employs a Direct Ridership Model (DRM) to predict boardings at the station level as a function of transit-supportive policies. We find that station-area focused policies promoting affordable housing and sidewalks on all streets in station areas or entire cities have a significant and positive impact on ridership if there are sufficient potential destinations in the immediate station area, measured as the number of Google places within 100 meters.

Based on our results, we stress the importance of station area affordable housing as a transit system efficiency measure, as well as for the social equity reasons it is usually encouraged. We recommend strengthening proaffordable housing policies and pro-sidewalk policies in Twin Cities station areas, supporting and encouraging for the neighborhood-scale commercial development that is required for their efficacy, and the continued implementation of pro-affordable housing policies and pro-sidewalk policies as the regional transitway system expands.