What’s the cost of choosing to drive a car instead of riding a bike?
By: Rodrigo Davies
Tags: Cycling, Transportation, Mobility

Every mile you ride is worth 32 cents to society — and every mile you drive costs us 18 cents, a study has found.

We think we know why promoting cycling and walking is a good thing. It’s good for the environment. It’s good for personal health. It reduces congestion and pollution. It promotes personal wellbeing and the perceived liveability of places.

But when it comes to justifying investment in cycling and walking infrastructure, one of the challenges is that it can be hard to quantify the benefit — to society and to the individual — alongside the negative impacts we’re avoiding by shifting travel away from cars. We can count traffic flows and cars, and to varying extents, pollution and congestion, but can we bring these factors together to understand the tradeoffs we’re making between different modes? Might being able to do so shift the relative level of investment we place in each mode?

Recently a group of researchers attempted to quantify the costs and benefits of cycling, walking, and driving to explore the broader impact of infrastructure investment in the European Union. They took into account a whole range of societal impacts, such as land use and cost pollution, as well as individual impacts, such as health benefits and travel time, in order to estimate the costs — and benefits — of cycling, walking, and driving both for society and the individual.

For instance, driving a car was found to have a cost to society of €0.11 per kilometer (or 18 US cents per mile) due to factors such as the associated pollution, land use, collisions, and infrastructure construction and maintenance costs. The cost to the individual of driving a car was €0.89 per kilometer ($1.60 per mile), due to factors including the cost of operating a car, travel time, congestion and parking.

Cycling, by contrast, generated a €0.18 net benefit to society for every kilometer cycled (or 32 US cents per mile), primarily due to the health benefits of physical activity. For the individual, cycling had a cost of course, due to perceived safety and discomfort, the risk of accidents, and the additional travel time required to reach a destination. Nevertheless, the cost was €0.14 per kilometer (26 US cents per mile), about one sixth the cost of driving a car.

Walking was found to generate the greatest net benefit to society (€0.37 per kilometer, or 69 US cents per mile), and although the personal cost was still much lower than driving, it was about three times higher than cycling (€0.50 per kilometer or 56US cents per mile) due to the extra journey time associated with walking.

What’s most exciting about this work is that it can be applied back to investments that have been made by local governments, to understand if they’re paying off or not.

Calgary has, in five years, recouped 75% of the cost of building the protected bicycle lanes.

In Calgary, Canada, a full network of protected bicycle lanes was built across the downtown core in 2015. By applying the methodology from the European research to bicycle count data collected on the network, it is possible to determine the net social benefit generated by the initial investment in cycling infrastructure.

The network of protected bicycle lanes cost C$5.5 million (Canadian dollars) to build. As every kilometer travelled by bicycle generates C$0.28 of social benefit, the network has generated C$4.1 million in social benefit and counting. That means that Calgary has, in five years, recouped 75% of the cost of building the protected bicycle lanes.

While no methodology is perfectly generalizable, it would be interesting to see more local communities attempting to quantify the costs and benefits (societal and individual) of infrastructure so that we can have a more holistic discussion about why mode shift matters — and remind ourselves that every infrastructure decision, especially continuing the status quo, has a cost associated with it.

Are you working on mode shift in your area? Let’s talk.