Bike shares and bike infrastructure

I’m currently reading Walkable Cities by Jeff Speck. In it, he talks about induced demand which is the common finding that widening roads, which is done to reduce traffic congestion, generally maintains or increases congestion. This is because, in the short term reduced congestion makes trips easier so people make more of them or more people make them. Another important factor is how things like wider roads make other modes of transportation harder. It takes longer for a pedestrian to cross a wider road for example which can mean that it switches from being easier to walk to being easier to drive.

That’s cars. I’ve often been an advocate that if you build better cycling infrastructure it will lead to more people cycling. While anecdotal, I do have some support for this view in my own life. Many people have told me that they would like to bike, or walk, more places but they are concerned about safety. They don’t feel comfortable riding in the road. In the past, I’ve met people and helped them find the safe route to their destination to help get them on their bikes. Personally, I’ve talked before in posts about how I will bike longer routes if I feel safer on them. So, it seems like there could be a form of induced demand with cycling infrastructure. If cities build cycling infrastructure, cycling is perceived as being a safer and more viable option. If it is safer, more people are willing to participate.

This is what Van Veghel and Scott (2024) set out to investigate. What is interesting about their research though, is that they looked at the impact of new cycling infrastructure on bike share use. Their findings are good evidence that induced demand happens with cycling infrastructure too.

Bike share usage increased after construction of a significant bike route. This alone is not conclusive because the construction finished as restrictions from the COVID-19 pandemic were lifted. This means that some people who may have taken public transportation previously may have switched to bikes to avoid crowded transit rather than because of the bike access. However, even this is potentially positive as those people could have switched from public transport to personal vehicles and presumably car shares rather than bikes.

Use of the route that became the bike route increased, while travel on surrounding roads decreased. This is important because it shows that cycling infrastructure can concentrate cyclists on certain routes. This potentially changes flows and subsequent safety on those other roads. I know that for me, I’ll typically take a quieter road over a busier one, but this often brings me closer to parked vehicles and the omnipresent fear of getting doored (when a driver opens their door without looking and the cyclist, with no warning time to avoid the collision hits the now open door).

The findings are significant. 47% of the trips examined post construction were classified as induced trips. That’s huge. And while this is just one study, it sets out some steps to examine induced cycling demand in other locations. Drivers currently have the loudest voices in most cities because our cities have been designed and continue to be modified in ways that increase drivers. But what happens as more cities invest in safe cycling and pedestrian friendly infrastructure? If we build it will induced demand for other modes beyond the personal vehicles result in larger and larger interested populations?