Friday, July 20, 2012
To paraphrase, a roundabout is a perfect circle where entering traffic yields to everything else and exits right to leave the circle. A roundabout is more of an orbital intersection, less of a perfect circle usually, where the lanes flow out and staying in the roundabout requires left turns. Roundabouts can efficiently handle a large volume of traffic but can not safely accommodate pedestrians, whereas traffic circles are the opposite.
Here is a chart created by WashU and distributed by Friends for a Better Boulevard (click to enlarge):
This looks fine and dandy, but I think it raises questions as to which of these we really want. I agree that this intersection will have to handle large volumes of traffic, but I am uncomfortable with it doing that unless major design concessions are made to promote walkability in and out of the circle as well. Why would we put an arch and a park in the middle of this, just to improve the view that motorists have, esp if people can't get to it?? I'm wondering if there is a way to engineer a hybrid roundabout and traffic circle.
Let me make one thing clear before I even open up this can of worms, and before anyone accuses me of straying from the reservation: I support whatever the consensus alternative is to anything above-grade. I just also agree that this debate needs to play out. For instance, while I love the amazing renderings produced by Andrew Stewart, who has also been helping the group, the bone I have to pick there is that Western Avenue does not flow into the circle. For me, Western Avenue and its high traffic counts, high prominence, high blight factor, and huge rent gap potential for development, is one of the main reasons to do this intersection RIGHT. I want to be on the record supporting the movement in its entirety and I support whatever a public process would yield, that said, I am looking to see Western Avenue flow directly into a circular roadway that can also accommodate pedestrians. A circle of some sort that does not accommodate Western OR pedestrians is only half as sweet.
Having made my unconditional support clear, I keep going back to the name "better boulevard." To me, a better boulevard means something other than the strict and narrow purview of what is better for motorists. I am looking for what is better for pedestrians, for bicycles, for transit, for quality of life, for the environment, for economic development, and the entire city as a whole. While there is no doubt that a roundabout is far superior to those ends than an earthen ramp or anything above-grade, I would also suggest that an old-fashioned traffic circle may be even better. IF there is a way to make a traffic circle work for high traffic counts.