FABB Blog

John Pickett, a federal economist, mounts the 20-year-old red touring bike that he’s dubbed “the Mule” just before 7 a.m. outside the shed behind his home in the Mount Vernon area of Fairfax County. Over the past decades, he’s put more than 33,000 miles on its odometer, and he’s ready to add 15 more.

As the rising sun breaks over the Potomac River, Pickett pedals northward along the Mount Vernon Trail. He is one of the Washington area’s growing number of bicycle commuters, and he’s due at work in Rosslyn in about an hour.

Getting into his rhythm near Dyke Marsh, the 57-year-old Pickett barely notices passing a brown wooden post. He has no sense of breaking a light beam, but this is where the National Park Service first detects — and counts — him.

It happens over and over again to Pickett and the approximately 2,000 others who use the trail each day. As they bike, run and walk the 18.1-mile path, they unknowingly trip a series of sensors. Those dozen sensors are connected to counters, which over time will tell a tale of who is using the route and at what times.

In the traffic-snarled capital region, where transportation alternatives are becoming increasingly important, this bike and pedestrian route and others like it across Northern Virginia, Maryland and the District have become “a secondary nervous system” for commuters.

“We know a lot about cars,” said Ralph Buehler, an associate professor of urban affairs and planning for Virginia Tech who has consulted with the Park Service. “Suddenly, we have data that enlarges what we can see about how bicyclists and pedestrians behave.”

Bike-friendly Arlington County, which works closely with the National Park Service, has placed the newest sensor, an expensive, state-of-the-art, French-made device, on the trail near Reagan National Airport.

Unlike older counters, this one can distinguish between humans and machines, using an induction loop embedded in a double-diamond pattern in the pavement. It senses when a bicycle passes over. That is paired with a passive infrared sensor that notices the direction of travel when a warm body passes by, creating a disturbance much like a boat’s bow wave. That minute-by-minute information is wirelessly uploaded each quarter-hour to a central database and sent to the county daily.

While pedestrians and bicyclists share the trail, reports show that two-thirds of the users are on two wheels. No one knows how many are commuter, but bright red Capital Bikeshare bikes are popping up with regularity.

That rent-by-the-hour bike program started with 100 stations in the District and 14 in Arlington in 2010. It now has more shared bikes in circulation — 1,890 — than any other region in the country, having just flown by the 4 million trip mark, with 22,000 members and expanded networks in the District, Arlington, Alexandria and, soon, Montgomery County. Bike commuting in Arlington has more than doubled between 2006 and 2011, and the D.C. Department of Transportation estimates an average of 87,000 bike trips per day in the region.