Wenjing Pu was in the first year of his Ph.D. program at the University of Illinois when Google Maps made their debut in 2005. Although these maps could help internet users discover routes to their new jobs or plan road trips, Pu, a civil engineering student, felt that the information presented was much too static. He set out to discover a way to feed a network like this with dynamic traffic data, to provide travelers with real-time information to aid them in getting from point A to point B.
Pu’s dissertation used location data from transit buses known as “probes” to estimate and predict urban street travel time. He even developed an algorithm to account for the time that buses spent picking up and dropping off passengers. Pu was among the first to use “big data” in this way, and he brought this expertise with him when he joined COG as a transportation planner in 2009.
“My goal is to help travelers be more informed,” said Pu. “Eventually, I’d like for someone to be able to choose a route, check historical travel conditions, and know exactly what to expect in terms of times and routes before they walk out the door.”
Pu brought the Transportation Planning Board (TPB) at COG on board with using private sector probe-based traffic data—making it the first metropolitan planning organization to do so. Although an outside company provides the data, Pu is still tasked with summarizing the data and calculating easy-to-understand performance measures.
Lately, Pu is largely focused on the development of the biennial Congestion Management Process Technical Report, which monitors and assesses congestion management strategies employed throughout the region, and the quarterly National Capital Region Congestion Report, which summarizes traffic congestion and travel time reliability performance measures.
In 2011, he received accolades for his study of the "before-and-after" traffic effects of the 2011 opening of the Intercounty Connector in Maryland using GPS-based speed information gathered from travelers who have agreed to share the information anonymously from their smartphones or in-vehicle navigation devices. The study was one of the first in the country to use such data to measure before-and-after effects. It showed that, after the ICC opened, traffic congestion on nearby local roads dropped, though by a similar share as did the rest of the region -- a likely result of the national economic recession and other factors. On an absolute basis, however, roads in the vicinity of the ICC saw a greater decline in congestion, as the area was already relatively more congested than the region as a whole.
Part of Pu’s role is to also find the best way to “tell the story” of his findings. He recently joined planner Ben Hampton for an interview with The Washington Post’s “Dr. Gridlock” Robert Thompson on summer-to-fall travel patterns. The two used the National Capital Region Congestion Report to explain the post- Labor Day “Terrible Tuesday” phenomenon, or the idea that the region’s commute returns to normal the Tuesday after Labor Day. Contrary to popular belief, Pu’s analysis showed that vehicle miles traveled on the highway only declined by less than 1 percent in the summer months. There is, however, a significant drop in average delays, likely the result of commuters’ flexible summer schedules, boosted by the onset of long summer days.
According to Pu, he feels “at home” in COG’s Department of Transportation Planning. Pu hopes that his work continues to help the region’s residents, and he is excited for the future of his field.
“Transportation has really been changed by this era of big data, we’re also experiencing a shift in hardware and a new sharing economy,” said Pu, referencing the arrival of carsharing services and connected or autonomous vehicles. “It’s a very exciting time.”