The diverging diamond
How a "complete street" makes a 180-degree turn away from a pedestrian- and bicycle-friendly environment.
A couple of weeks ago, I ran a short blurb in a Friday News Digest about the idea of a diverging diamond interchange. Here's what I said:
Speaking of videos and engineers, did we need more proof that the engineering profession is insane than this video of the "diverging diamond". If we had infinite resources (we don't), this would still be crazy, but the fact that we're broke just shows you how insulated from reality so many of them are. Hey, engineers -- watch my TED talk on the difference between a ROAD and a STREET. You're trying to rid yourself of accident-prone left turns? Well, how about just build ROADS where there is no need for left turns and STREETS where they are no problem, instead of the STROADS you build today. I'm not joking.
There were some hard feelings in the comments section about my categorization of the diverging diamond -- and the egineering profession that developed it -- as insane. In a spirited discussion, one of our readers posted a video of an engineer giving an enthusiastic tour of the pedestrian features of one diverging diamond. For me, it was irresistible.
The following video is my "response". Sometimes I feel as if I'm shouting into the wind with the engineering profession. This may just be more of that. If nothing else it was theraputic to me. Hopefully it provides some value and insight for our readers.
As a final note; while I acknowledge that I did pick and choose the comments of the enthusiastic engineer that I wished to highlight, I did not edit the video or his comments. I don't think I took any out of context either. Please listen for yourself and see if you agree with my "insanity" assessment.
Charles Marohn is a Professional Engineer licensed in the State of Minnesota and a member of the American Institute of Certified Planners. He is president of Strong Towns, a non-partisan, non-profit organization that advocates for changes in development patterns and a complete understanding of the full costs of methods of growth. Strong Towns is seeking tax-deductable, $25 donations from 100 readers to create a video version of its Curbside Chat presentation.
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