Sometimes you never know when a driving trip for a vacation might provide a totally unexpected benefit.
But that’s exactly what happened when a recent multi-state journey included passing through southwest Missouri and specifically the city of Springfield. For those who haven’t been there, Springfield is that state’s third-largest city with about 170,000 residents and a metro-area population of more like 450,000 people. In other words, it feels a lot like Colorado Springs from the 1990s.
The driving route involved coming into Springfield from the north on Missouri Route 13, actually a four-lane highway. As it reaches the city, Missouri 13 intersects with Interstate 44, a major freeway that follows a southwest-to-northeast path from Wichita Falls, Texas, to Oklahoma City, Tulsa, Springfield and St. Louis (largely following the track of Historic U.S. Route 66).
When you’re a stranger coming upon that interchange in north Springfield, you might be confused at first by how the thoroughfare seems to weave left and right.
But for someone from our part of the world, it quickly led to a different realization. This actually was the exact kind of Diverging Diamond Interchange, also known as DDI, that’s about to become reality in Colorado Springs — specifically at the I-25 exit for Fillmore Street, where work is just beginning.
Like many, we’ve had trouble grasping how the Diverging Diamond concept works, and as we understand it, more than a few businesses and commuters who regularly pass through the I-25/Fillmore area also fear it might create problems and drive confused people away. Colorado Department of Transportation folks have been reassuring, calmly trying to explain that everyone will appreciate I-25/Fillmore much more when it’s done. But that hasn’t been good enough for many skeptics.
Then came the unplanned experience in Springfield, where a handful of the Diverging Diamond Interchanges have been constructed in the past five years or so. Actually, the one we encountered was the original, finished in 2009.
After going through several of them in and around Springfield, count us among the believers fully convinced the DDI project will make a huge difference at I-25/Fillmore.
There are several reasons why. One, it’s cheaper and has been proven to work, as a Missouri transportation site says, “where space and funds are limited.” Two, it doesn’t involve the major cost of flyover ramps or lanes, largely utilizing what’s already in place with some alterations.
Three, and most important, the idea works. We won’t try to explain every detail, but a few points stood out from Springfield:
It eliminates the lines waiting to turn left onto the interstate. As you approach from either side, you first can exit right onto the interstate. But then the lanes cross upon reaching the overpass, which moves each side to the left and allows vehicles to turn left smoothly onto the entry ramp for the interstate without waiting for oncoming traffic, a light or turn signal. Also, cars exiting the interstate can merge left or right onto the secondary roadway (Fillmore here) without stacking up waiting for a stoplight.
No left-turn lines, no left-turn signals. The lights on each side of the overpass simply allow traffic to flow straight through, helped by medians and signage. Congestion and crashes decrease considerably. Nobody sits waiting on the overpass itself (many of us know the disconcerting sway as cars now sit on the Fillmore bridge over I-25).
Since most folks won’t be driving to Springfield, check it out for yourself at tinyurl.com/n9epfma. And in a year or so, Colorado Springs will be the latest example.