You might know that the Red Line train you board every morning is crowded. But WMATA, Washington DC’s transit agency, needs more information than that to improve service.
Data on train and bus conditions, as well as on people’s travel patterns, is exactly what WMATA’s Office of Applied Planning is seeking through its new initiative, “Trace.” This program syncs anonymized SmarTrip card “tap” data (information from the Metro fare gates and buses on where users enter the system) with vehicle locations, allowing WMATA’s planners to make educated guesses on which trains or buses riders boarded and how crowded those vehicles were.
Existing methods of counting riders – such as automatic people counters built into buses and manually counting people exiting a station – aren’t entirely reliable, explained Catherine Vanderwaart, an analyst from the Office of Applied Planning at last week’s Transportation Techies meet-up group. Trace provides a workaround.
SmarTrip card data also helps WMATA monitor the impacts of track work on ridership. Vanderwaart plans to apply Trace and its data to the long-term understanding of behaviors like mode choice and to informing decisions on system capacity.
WMATA isn’t the first transit agency to combine card data with vehicle locations. Transport for London (TfL), in a partnership with MIT dating back to 2005, built a program similar to Trace and uses it routinely to give automatic fare refunds (similar to WMATA’s Rush Hour Promise) and inform service decisions.
An explanation of Transport for London’s data matching program.
In 2015, TfL reported that it used this program to inform bus service during the emergency closing of the Putney Bridge to buses the previous year. Because they discovered that most bus riders crossed the bridge in the middle of one bus trip, they set up transfer facilities on either side of the Thames so riders would not be charged for two bus trips after crossing the bridge on foot. TfL also sent emails to riders who would be affected.
Andrew Carpenter contributed to this reporting. Photo by Sam Kittner for Mobility Lab.