When the Seattle Department of Transportation plans the coming downtown network of protected bike lanes this year, it will do so with a new tool in its arsenal: detailed data about the riding habits of thousands of Seattle bicyclists.
The data comes from Strava, an app and website that tracks the route, speed, distance, time and elevation of cyclists and runners.
The app started as and still is primarily a way for bike racers and recreational riders to track their training efforts and compete against each other virtually. (Strava has leader boards for fastest times on user-created segments, such as a certain hill climb.) But many users track all of their mileage including their daily commutes and trips around town.
And that's what interests the city.
According to Michael Oldenburg, Strava’s senior communications director, nearly half of the rides uploaded in major metropolitan areas are from people’s commutes. In May 2014, Strava started bundling data it collects from the 2.5 million-plus trips uploaded each week and licensing it to city transportation and planning departments through a program called Strava Metro. To date, government departments in Oregon, Orlando and Arlington, Virginia, have used it, along with cities in Scotland and Australia.
According to Sam Woods, the multimodal program manager for the Seattle Department of Transportation, the city plans to license about $5,000 worth of data from Strava to help plan the Center City Bicycle Network, the system of protected bike lanes they’re building downtown. Given Strava Metro’s pricing of 80 cents per user’s data per year, SDOT will be getting information on about 6,250 people.
The Center City network is still in its early planning stages, but the city received $5.8 million in federal funding to build protected bike lanes on Seventh and Fourth avenues and SDOT Traffic Engineer Dongho Chang has said department officials are looking to build protected bike lanes on east-west corridors as well.
For SDOT, Woods says, one of Strava’s appeals is that it sheds light on the ways riders get through town. “We have counts at various locations of cyclists, but we have no origin-destination data or the specific routes that cyclists are currently using," she says. Using Strava, "We can identify demand corridors.”
The Strava data will be used along with SDOT’s traditional sources such as roadside counts, analysis of existing road conditions and information gathered at public outreach sessions.
The Strava data is also less expensive than traditional counts SDOT might have had to conduct, she says. “We can extrapolate individual counts to the entire network allowing a more accurate demand analysis of all streets and paths. This is very cost effective compared to counting hundreds of locations.”
Some people worry that the data doesn’t represent the breadth of users who will be using the downtown bike lanes once they’re built, both because Strava is used primarily by racer-types and because using it requires either a GPS unit or a smartphone.
Cascade Bicycle Club Advocacy Director Jeff Aken says, “As advocates and planners we need to always be mindful that the data only shows an extremely small subset of riders. Strava can inform our outreach and community engagement, but does not replace it.”
Strava’s Oldenburg says that when it comes to city routing, company officials have largely found commuter and recreational riders' route choices to be the same. "Recreational riders and commuters typically follow the same streets because generally there's a bike lane or an understood ‘best route’ that people all use.”
That said, Oldenburg recognizes it’s not a catchall tool. “We certainly don't say Metro is the end all be all data set for cities," he says. "But it's the first of its kind and a very broad data set that hasn't been available in the past.”
Despite the concerns about its representational limits, Cascade Bicycle's Aken is enthusiastic about adding Strava to the pool of planning tools. “The data Strava and similar apps provide is amazing. The maps can show how people move through complicated intersections and highlight how cyclists travel around the region. It also allows us to see what, if any, differences exist in route preferences by gender.”
He continued, “Ultimately we need better data on everyone who is currently bicycling or wants to ride, whether for work, recreation or utility purposes regardless of age and ability."
As city officials work on the network, the data will get a real test.