Bike to Work Day, celebrated throughout the DC-Maryland-Virginia region, is meant to get people out of cars, reduce congestion and emissions, and improve public health. But how effective are such events in the long run? A new study of the Sacramento, California region indicates that, in isolation, annual bike promotion events have limited long-term impact. However, these events should be looked at as part of a larger effort to promote biking. For instance, when used in conjunction with other bike educational campaigns and/or the addition of new bike infrastructure, bike to work days, weeks, or months can be an effective tool to encourage biking. As so often, more research is needed.
The new study, Travel Behavior Impacts of Transportation Demand Management Policies: May is the Bike Month in Sacramento, California, examines one of the most extensive bike to work events. The preliminary conclusion is that people who hadn’t previously done much biking may do more; “participants who were considering bicycling more and usually traveled by modes other than bicycling . . . more often increase their bicycling frequency than individuals who had already been regularly bicycling.” This is the good news. The bad news is that, “this increase was only temporary and seems to have disappeared after the end of the campaign.”
However, a glance at the underlying numbers, can be interpreted more optimistically. Twenty-five percent of survey respondents biked 5-7 days per week prior to bike to work month, the number went up to 30 percent during that month, and then shrunk to 25 percent after, for a net 5 percent gain. Numbers were also solid for those who biked 3 to 4 times a week, from 15 percent to 21 percent and then down to 20 percent.
These encouraging results in the direction of behavior change warrant more research. The study is “an attempt to understand the possible effect of the campaign after accounting for sampling bias and other confounding effects,” Jai Malik, a PhD student at the Institute of Transportation Studies and co-author of the study, explained in an e-mail. As Dr. Giovanni Circella, the Director of the 3 Revolutions Future Mobility (3RFM) Program at the Institute of Transportation Studies, who was the principal investigator of the study, explained, “Some self-selection of the respondents might be in place, with those that were more enthusiastic about the program remaining engaged and completing also the after survey.” Individuals who bike already are over-represented, and the results could therefore be biased. .
Furthermore, the weather in May, when the event takes place, is better for biking than before–an excellent reason to choose May to encourage biking, but one that warrants more research and analysis. The model used by the study “shows that change in the weather was indeed one of the factors which led to the increase in biking,” Malik said.
Still, the data provided can be interpreted as positive for bike to work events. It is encouraging that, according to the study, “individuals who usually travel by car, walk or transit as a typical mode of transportation were the ones who more often reported an increase in bicycling during and after the campaign.” This indicates the objective of decreasing car trips is being at least partially met, although the flip side is that those who already bike were unlikely to bike even more. However, “Almost 70% of participants reported that their bicycling frequency” during and after bike to work month was similar, “suggesting that habits created during the campaign persisted.”
The survey data draws on 1,970 observations, reduced to 1,727 after “data cleaning.” Survey respondents had a larger proportion of higher-income and better educated adults and 58 percent were males.
What the study means for Arlington
Not surprisingly, given its innovations in transit and walkability, Arlington is one of the key biking jurisdictions in the United States. In recent years, the share of work trips done by bikes has increased dramatically, from 0.6 percent in 2006 to 2.4 percent in 2016, settling down a bit to 1.5 percent in 2018, according to data from the Census Bureau American Community survey (provided by BikeArlington). However, Henry Dunbar, Director of Operations, Active Transportation, Arlington, emphasized that counting bike trips is difficult, leading to unevenness in the results. And a short trip to public transit is not counted in these number. Nor are bike trips for errands and recreation, which constitute a major area for future research.
Still, Arlington does extremely well in national bike rankings, coming in as the eighth best biking city in North America in the Places for Bikes rating system. Although ridership is somewhat low compared to other top cities, safety and growth rate are high. Dunbar did point out that Washington, DC has much better ridership numbers, about double that of Arlington, but these are due largely to density. He added that Arlington’s biking and walking contribute to its rating as the fittest city in America.
While the study indicates that bike to work programs, done in a vacuum, have a limited impact, in conjunction with other educational programs and/or bike infrastructure, they likely have complementary effects. For instance, the study pointed to research that in Australia highly successful “comprehensive programs included targeted information, events and incentives to promote bicycling.”
This comprehensive approach has long been Arlington’s. We “can’t just do these bike to work days, months and weeks in a vacuum,” said Dunbar. “Our efforts have really tried to cater toward getting the reluctant riders to start.” Programs need to be year round. In Arlington, there are outreach events every month, as well as classes to help inexperienced riders feel comfortable in traffic, and even a book club. BikeArlington also includes helpful maps geared to different bicyclists’ comfort levels and showing different routes for biking to work or recreation, as well as intriguing tools, such as RackSpotter to help with bike parking.
Making biking easy is key. Dunbar emphasizes “helping people with wayfinding, helping them with solving what the regular rider has already figured out . . . and we do that year round, everything from getting people just to learn how to ride” to dealing with “extreme weather conditions.” As winter approaches, for instance, Arlington will hand out lights and reflective gear to help novice riders realize they can bike all year and in multiple conditions.
Dunbar also emphasized working in cooperation with local businesses, for instance to include showering facilities and sufficient bike parking. It’s also critical to work across agencies and communities, such as police and with housing agencies, as well as to cooperate across borders, with other local governments and with advocacy organizations.
Of course, infrastructure is key. The “bikeability of the neighborhood” is a crucial factor, Malik told me, encompassing infrastructure, safety, and accessibility. In Arlington, bike infrastructure includes not just bike lanes, but bike boxes to assist bikes at lights, buffered lanes that provide additional space between bikes and cars, HAWK Beacons to assist bikes and pedestrians in crossing busy streets, copious off-street trails, and wayfinding signs.
The “gold standard” for bikeability, however, and the current focus of much bike advocacy, is protected bike lanes. These use such methods as plastic bollards or a physically raised surface to give even novice bicyclists a feeling of safety. Arlington first installed such lanes in 2014 and added to them in 2016, but still has a long way to go for a connected network that would likely draw large numbers of new bicyclists. Indeed, the county currently only has 2.9 miles of protected bike lanes according to the Master Transportation Plan, Bicycle Element. However, Arlington does plan to complete 75% of a “Low Traffic Stress Bicycle Network by year 2025 and 90% by year 2030.”
Bike to Work Day reminds us of what Arlington’s bicycle policy and advocacy has already done and of what it hopes to accomplish in coming years.