Tracking the Tracks

If D.C.-area commuters start feeling like hamsters crammed into a maze this summer, they won’t be too far off. That’s because they have been thrust into a remarkable transportation experiment.

Washington’s Metrorail has embarked on its unprecedented “SafeTrack” maintenance program—which squeezes three years of repairs and upgrades into one—and UMD researchers are surveying riders and analyzing how the service reductions and shutdowns affect the rest of the region’s transportation network.

Unlike unpredictable public transit disruptions such as breakdowns and worker strikes, this concrete schedule of 15 outages provides an ample chance to get before-and-after data, says Lei Zhang, director of UMD’s National Transportation Center (NTC@Maryland) and Herbert Rabin Distinguished Professor in the Department of Civil and Environmental Engineering.

“It’s a very unique opportunity,” he says.

For each of the 15 SafeTrack projects, NTC@Maryland will predict, analyze and release a report on traffic conditions. The first report, released on June 9, looked at the impact of fewer trains running on the Orange and Silver lines from the East Falls Church to Ballston stations. It found that the number of vehicles on I-66, I-395 and I-495 near the project on Monday, June 6, increased just 3 percent compared to the previous eight Mondays in April and May.

The result, in line with typical daily fluctuations, isn’t surprising based on surveys of more than 200 Metro riders: 39 percent reported that they didn’t intend to change their riding plans; 34 percent said they would alter only their departure time; and just 9 percent said they would drive alone instead.

“We’ve seen a lot of evidence of inertia,” Zhang says. “A lot of people don’t want to use other modes until it really hurts them.”

Consequently, Zhang expects rider responses and traffic impact may be different for subsequent SafeTrack phases, which will feature complete shutdowns of some Metro service areas. He is also interested in further studying why just 3 percent of surveyed riders said they would use options such as Uber, often hailed as the future of transportation.

“This is the first time we can observe how people will use these emerging rideshare services,” Zhang says. “Why is it not a lot of people see them as a viable option?”