How do bike lanes decrease traffic?

What happens when you add bike lanes to city streets? Do they keep bicyclists safe? Do they ease or increase traffic? The Guardian looks at how bike lanes helped reduce congestion in London and Paris. From the video:

“Traffic is no more than people making decisions about where, when and how they travel from one place to another. This means that taking road space away from cars, in favor of bikes in many cases can reduce congestion, because you’re making car travel less attractive while enticing people to travel by bike, public transport, or walking.”

“All the evidence,” the video summarizes, “points to bike lanes having a positive impact on congestion, pollution, and our health.” In addition to making city streets less crowded, biking, public transportation, and walking increases exercise and decreases carbon emissions.

Two key ideas:

Induced Demand: Increasing road capacity tends to attract more cars, leading to congestion. Conversely, reducing road capacity by introducing bike lanes can encourage biking and discourage car use, alleviating congestion. When a city’s public spaces are connected by a robust bike lane network, the demand for biking is created.

Traffic Evaporation: When road capacity is reduced, some car trips may disappear because of convenience or congestion, either because people choose alternative modes of transport or because they combine or eliminate trips altogether.

Many short car trips could be replaced by cycling, walking, or public transport, suggesting a significant potential for reducing car dependence.

“In Hackney, east London, 17% of residents have had some roads in their neighborhoods closed to motor vehicles and those neighborhoods have seen a 40% reduction in traffic as a result. In Paris, roadway restrictions have contributed to a 5% drop in car trips since 2010. While the city has also seen a 54% increase in bike use, from September 2018 to 2019.”

And since this video was published in 2022, cities like Paris have expanded their car-free zones. Through child-friendly initiatives aimed at pedestrianizing and limiting motorized traffic in the vicinity of nursery and elementary schools, Paris is actively creating safer environments for residents of all ages.

Watch these related videos next:
• Why, Traffic, Why?
• What is a bike bus?
• Bicycle rush hour in Utrecht, the Netherlands’ fourth largest city