Would Kansas City Bike Lanes Actually Save 36 Lives per Year? Probably Not

Kansas City officials are working on a draft of the Bike KC Master Plan, a strategy for increasing bike lanes within city limits. Advocacy group BikeWalkKC says that the plan, which could cost taxpayers anywhere from $387 to $418 million, would save 36 lives per year if implemented. But how do we know that’s true?

It is important to realize that this marketing campaign, even though it uses biker-oriented talking points, is not talking about 36 cyclist lives—the latest annual data from 2017 showed zero cyclist fatalities. Instead, it estimates:

• 15 lives saved by increased physical activity
• 6 lives saved by improved air quality
• 15 lives saved by a reduction in fatal car crashes (not crashes that occur because a cyclist was involved—any fatal car accident counts)

Only the physical activity category is directly connected to bikers who would use the lanes.

There are problems with these estimates. Physical activity benefits, while hard to measure, are dependent upon more Kansas Citians choosing to bike instead of drive. Only 0.3 percent of commuters used bikes in 2018, and a survey noted that fewer than 50 percent of respondents were interested in biking more. More bike lanes could mean an increased number of bikers—but it’s just a projection, and there’s no way to know how many more bikers we’ll see with expanded bike lanes, let alone what the actual health benefits will be.

Six lives saved by improved air quality also seems a stretch. The number was achieved by expanding data from research in New Zealand. Even if this study was properly applied to Kansas City, the boasted number is the highest estimate possible. An economic summary of the Bike KC Master Plan read:

Assuming 1 death due to air quality for every 100 million vehicle miles traveled and 1 per 40 million vehicle starts (trips), the bike plan could reduce Kansas City air pollution fatalities anywhere from 1-6 deaths per year . . . [emphasis added]

The most puzzling estimate is that of fatal crash reduction. The economic summary of the bike plan noted that 228 fatal car crashes occurred within the city limits of Kansas City from 2015-2017, and that 94 of these occurred along the route of the proposed bike lanes. While the summary boasts a 47 percent reduction in these crashes due to the way bike lanes will change the flow of traffic, no crash data was included.

Upon reaching out to the authors of the economic summary for more information, I was told that they did not have any data on the cause of these car accidents: 

The dataset provided by the Mid-America Regional Council did not provide any context on the causes of the crash. There has been some analysis of the contributing factors in fatal crashes . . . but our FHWA source on road diets does not differentiate by crash cause or even crash severity. It is simply an empirical measure on the impact of road-dieted streets on total crash volume. These benefits accrue to all users, regardless of mode or how many people take up bicycling.

How can a 47 percent reduction in fatal crashes be a realistic estimate when there is no available data on what caused the crashes? If the reduction is due to fewer cars traveling the roads with the bike lanes, does that simply mean the crashes occur on the alternative routes these cars travel? Stating the number of crashes occurring within city limits and presenting some traffic flow statistics from other areas does not seem compelling. If BikeWalkKC wants to claim 15 fewer lives taken annually by fatal car accidents as a result of expanded bike lanes, shouldn’t there be more data to back that claim up?

By portraying the Bike KC Master Plan as a strategy that will save 36 lives per year, BikeWalkKC is not avoiding the real problem at hand: this project will cost hundreds of millions in taxpayer dollars, money that could be better spent elsewhere. As my colleague Patrick Tuohey noted,

Kansas City has significant needs, significant transit needs. They are not biking. It is infrastructure. It is infrastructure repairs. It’s getting those steel plates off our streets.

The use of questionable statistics will not help develop solid city policy. If the city has millions of dollars to toss around and is concerned about saving lives, a better idea would be hiring more police officers, not building more bike lanes.