Roundabouts are just plain better
News today suggests some much-need improvements are scheduled for the I-95 intersection with Pooler Parkway and the airport in Savannah. From the article:
The Savannah Airport Commission on Wednesday voted to spend $67,500 as part of a joint agreement with the Georgia Department of Transportation, Gulfstream Aerospace and the Outlet Mall of Georgia to ease traffic congestion at the I-95/Pooler Parkway/Airways Avenue interchange.
Meanwhile, the airport, Georgia DOT, the outlet mall and Gulfstream have come together to jointly fund interim improvements.
Those include adding dual left-turn lanes to the northbound exit ramp of I-95, extending the existing westbound left-turn lane on the bridge over I-95 for traffic onto southbound I-95 and adding a right-turn lane for eastbound traffic onto southbound I-95.
Two traffic signals also will be modified.
Like I said, this is much-needed. The intersection is a real mess. It backs up many hours of the day, it's hazardous for traffic exiting from I-95 and frustrating for those trying to get to the airport. Development is booming on the Pooler side. Improvements are absolutely needed.
Here's an aerial of the current intersection:
It's unfortunate to me that GDOT is following the "typical" path here of more lanes, a bigger intersection, traffic signals etc.. By now, there's more than ample evidence from around the country that roundabouts are a far better solution in situations like this. Why are they better?
1. They are safer. Multiple studies show not only fewer accidents, but far fewer accidents with injuries or death.
2. They take up less room. Multiple-turn lane signalized-intersections are huge. Even a two-lane roundabout would be smaller.
3. They don't fail as often. Signals rely on electricity, which often fails. When they do, it's chaos. Roundabouts are simple and don't require mechanical activity. Some would call this Antifragile.
4. They are less expensive. Roundabouts cost less to build and far less to operate/maintain. I like the idea of saving money.
5. They require less road improvements downstream. Most people don't realize that roads are sized based on intersection capacity. Because roundabouts are also so efficient (traffic is always moving), the approaching roads don't need to have as many lanes. That also saves money, and creates more land for beautification and development.
People sometimes object to roundabouts, claiming they're confusing or scary. Look, traffic signals were new once, too, and people learned how to use them. I don't believe people are so stupid that they can't figure these out as well. In fact, they're common throughout the world, just not as much in the US.
Some examples from aerials below:
And for good measure, here's an example from France near a suburban mall and interchange:
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