That ol' diverging diamond

I'm neck deep in prepping for the 26th Congress for the New Urbanism (CNU) where I'll be making a presentation, podcasting multiple times each day, taking part in some meet-ups and then hosting a series of debates Friday night. You're going to get a lot of that, so buckle up. You can see the full schedule here.

The downside is that I don't have a ton of bandwidth for my normal Monday article. So, in a quick recap, I want to share something I put together back in 2011 that has come back on my radar recently.

Way back then, I was sent a video by an enthusiastic engineer who was extolling the pedestrian-friendly features of the Diverging Diamond Interchange (DDI). His walking tour was everything I've come to expect from those in my profession (with a growing number of notable exceptions).

Instead of displaying any knowledge of what the experience of being a human on foot is like, the video tour focused on engineering checklist items, superficial treatments and bizarre anecdotes. I decided to narrate a response to his narration. Here's the result, from 7+ years ago:

The reason it's back on my radar is because, while it sat dormant for a while, somebody must have shared it in engineering circles because I've been getting a rash of comments lately.  Some of my favorites include:

I love the notion of me being "the worst example of our dramatic outrage culture" — my kids would find that funny. I also find it fascinating how comment after comment insists that DDI is a huge success because it handles traffic well. Yeah, I'm sure it does, but the video I was reacting to tried to make the case that it was "pedestrian friendly" which it most certainly is not.

Here's one I chose to engage with:

I should have quit there, but I attempted to answer the question by putting forth the statistic I would use to judge whether something was really pedestrian friendly: do humans outside of vehicles actually use it?

So what would a statistic be? I'll suggest two, reject the former and bolster the latter.

#1: Pedestrian crashes. While many engineers would cite this statistic as proof of something, I reject it for the obvious reason that the design, as despotic as it is for people attempting to walk or bike, will suppress walking and biking. Discouraging people from walking and biking is not really a sign of success.

#2: Pedestrian traffic. If pedestrian traffic is noticeably increasing to a volume that is statistically significant, then I'd cheer that the DDI is creating a safe and inviting environment for people to walk and bike. That would also make crash statistics have some validity.

Regardless of what is happening with stat #1, stat #2 is not occurring. That puts my back into the entire loop of asking: why are we pretending this is pedestrian friendly? Do we really care about people outside of a car? If so, this is a pretty terrible way to show it.

It will not shock you to learn that this conversation didn't go far. I opted out, but the comments continue to trickle in. While the engineering profession has made a lot of progress in the intervening years, I'm continuously reminded just how far we have yet to go.

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