The non-profit organization People For Bikes recently released its annual ranking of the bike-friendliness of cities. What I find most interesting was a discussion of cities that improved the most last year, including Salt Lake City, Utah. The city did some major infrastructure improvements including the 9 line trail along an abandoned railway and improved bike lanes on major streets. But what really caught my eye was that the city reduced the speed limit along 420 miles of local roadways from 25 to 20 mph, in an attempt to lower pedestrian fatalities ( a local engineer said “Only about 4% of the crashes in our city involve bicycles and pedestrians, but they make up more than 46% of all the fatalities that we have here”). A local advocacy organization “sweet streets” has pushed for this with the phrase “20 is plenty”. I like this for two reasons. The first is that evidence shows that the likelihood of a fatality in a collision between a motor vehicle and a pedestrian or cyclist goes down dramatically as speed limits are lowered. The second is that I remember this being emphasized in a book about cycling in the Netherlands [1]. Everyone assumes that the bike friendliness of places like Amsterdam results from good infrastructure, which is indeed part of the solution. But also of great importance is that speed limits in residential areas are often much lower than in the US, like 15 mph vs. our more common 25. Going from 25 to 20 is a big step in the right direction. I liked this comment from a city councilman on the decision: “We as a nation really have inherited generations of traffic engineering only focused on getting cars from point A to point B very quickly and not focused on making the streets safe for all modes of transportation.”
References
Bruntlett, M, and Bruntlett C, Building the Cycling City: The Dutch Blueprint for Urban Vitality, Island Press, 2018.
