Study: Induced Demand Works for Bikes and Transit, too

‘Induced demand’ is a common trope among planners, usually signifying the futility of building more vehicle lanes in an effort to reduce congestion. “If you build it, they will come,” lament multimodal transportation advocates.

But the same concept works both ways, writes Kea Wilson in Streetsblog USA. Building multimodal infrastructure, according to a new U.K. study, will also induce demand for biking, walking, and public transit.

In what may be a global first, a team of researchers at the University of Cambridge in the United Kingdom finally put hard, country-wide data behind the intuitive idea that building multimodal infrastructure like bike lanes and rail lines will — surprise! — get more people biking, taking transit, and leaving their cars at home, at least in their home country.

The research helps counter arguments that new bike lanes, bus lanes, and pedestrian infrastructure won’t be used once built. However, induced demand due to infrastructure is just one of several factors that influence mode choice. “When a driver takes a newly built highway lane, after all, that decision isn't just motivated by a desire for a slightly faster commute on some fresh asphalt — which that driver herself quickly undermines as she and all the other drivers quickly form a traffic jam. It's also fueled by public attitudes that stigmatize and even criminalize other ways of getting around, subsidies that make motoring artificially cheap, and a raft of non-infrastructural policies that make taking another modes inconvenient, dangerous, or outright impossible.”