04/18/2025

The Lack Of Science In Road Design Is Deadly

17:31 minutes

High angle looking top down view of complicate road and expressway intersection in Bangkok city of Thailand. Shot by drone can use for transportation or abstract concept. Road design
Credit: Shutterstock

If you’ve seen a car crash on the side of the road, you might look at it and think that the person at fault is the driver. But how much blame should be shared by the people who designed those roads in the first place?

Well, some traffic engineers are calling for the field to accept more blame for the crashes and the tens of thousands of annual fatalities that happen on our roads, including Dr. Wes Marshall, a professor of civil engineering at the University of Colorado Denver. In his book Killed By A Traffic Engineer: Shattering the Delusion that Science Underlies our Transportation System, he digs into the standards that have dictated traffic design for decades to find out exactly how much science they’re based on. Spoiler alert: It’s a lot less than you’d think.

Host Flora Lichtman sits down with Dr. Marshall to talk about how we got to this point and what a safer version of our streets could look like.

Read an excerpt from Killed By A Traffic Engineer.


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Segment Guests

Wesley Marshall

Wesley Marshall is an associate professor of civil engineering at the University of Colorado, Denver.

Segment Transcript

The transcript of this segment is being processed. It will be available early next week.

Meet the Producers and Host

About Dee Peterschmidt

Dee Peterschmidt is a producer, host of the podcast Universe of Art, and composes music for Science Friday’s podcasts. Their D&D character is a clumsy bard named Chip Chap Chopman.

About Flora Lichtman

Flora Lichtman is a host of Science Friday. In a previous life, she lived on a research ship where apertivi were served on the top deck, hoisted there via pulley by the ship’s chef.

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