Oregon wants to make its roads safer and more convenient for cyclists, but has a problem—it has very little data on where people ride and what influences their choices. So it turned to an outfit that has loads of data on that: Strava.

The Oregon DOT is poring through reams of data provided by the popular app, used by cyclists to track, among other things, where and when they ride. The information could be used to help shape transportation projects.

“We were really deficient on the cycling and walking side of data,” said Margi Bradway, the active transportation lead at the Oregon DOT. State officials could build bike lanes where they seemed logical, but they didn’t really know where they were most needed or if those that were built were popular. With the hard data from Strava, educated guesses become informed decisions.

The idea to tap the power of Strava came to Bradway in the summer of 2013. She was on a ride and noticed everyone tapping away at Strava during a break.

Strava jumped at the chance to sell the data and finalized the deal in September. That’s led to similar partnerships with London, Glasgow, Orlando, Florida and other cities. and other cities, creating an unexpected new revenue stream for an app designed to help cyclists and runners connect online, share their progress and encourage each other.

For $20,000 a year, transportation planners and others can access Strava Metro, which provides an unprecedented look at where and how people are biking. It can tell them where they speed up and slow down, for example, or where they might stay in the street or ride on a crosswalk. That information can reveal where bike lanes or traffic calming measures would be useful, and if those already installed are effective.

“Without better data, they can’t ask those questions,” Strava co-founder Michael Horvath said. “Strava Metro has the potential to provide the answers.”

Current methods of counting cyclists take a ton of time or a ton of money. The DOT can videotape traffic and have someone sit at a monitor and count cyclists, or it can send someone to sit on the sidewalk and watch them go by in real time. Neither method is terribly efficient.

Bike counters—bulky devices embedded in the ground—are less tedious and time-intensive, but cost as much as $20,000 and provide data for one specific location. That makes spending $20,000 a year for everything Strava knows look like a bargain. It was an easy sell for the DOT brass, Bradway said, especially when they saw the data they’d be getting.

The Strava data has been “fairly eye-opening,” Bradway said, since “we don’t have a good understanding of why people ride when they do.”

At one intersection, for example, transportation planners discovered cyclists coming from the south would slow down before crossing, while those coming from the north would come to a stop and then walk their bikes or ride slowly. It was the first time planners could see that, and they realized the intersection posed a risk to cyclists.

In another case, the DOT installed rumble strips on Highway 26 near Mount Hood. The strips are a great way to help drivers avoid running off the road, particularly at night, but they’re a nightmare for cyclists. Strava data revealed where cyclists were getting off the highway and where they were getting back on, possibly to avoid the rumble strips. At those spots, planners could consider alternative, more cyclist-friendly safety options, like signs and lights.

The data is far from perfect, or even complete. Its data for Hawthorne Bridge, a major bike commute corridor in downtown Portland, represents just 2.5 percent of total cyclists, Bradway said.

Obviously, Strava only track riders who have a smartphone and use the app. The company won’t say how many users it has, but claims users worldwide upload 2.5 million activities—which include rides and runs—are uploaded each week.

Strava is used by recreational riders more than commuters, so you could argue a lot of its data isn’t relevant to urban commuters. But Horvath argues that even a San Francisco cyclist headed to the far side of the Golden Gate Bridge to ride in Marin County will move through the city using the same routes a commuter would.

Users with privacy concerns may not be thrilled to know Strava is selling data, but Strava scrubs personal information before it goes out. What’s more, once cyclist is, from a computing standpoint, indistinguishable from another, once he’s on the street, so you can’t follow a specific person for the duration of a ride.

Horvath says Strava Metro will be an important revenue source for the company, but it doesn’t change the company’s underlying goal: Making life better for cyclists, Horvath said. If it can help cities change for the better, it’s still doing that.

The Oregon DOT considers the Strava deal a pilot project, and it’s still using its more traditional methods of tracking cyclists. But it is first time Bradway and her colleagues have been able to see not just where cyclists are, but “how people ride and how they make decisions.”