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Text from North Carolina roundabout engineer Jim Dunlop, P.E., North Carolina Department of Transportation writing in the Roundabout Research listserv this week:
I thought it was the Wilmington traffic engineer. Turns out it was a traffic enforcement officer from Wilmington. He set up his patrol car in the middle of the intersection, to warn drivers to that the signal was out. He then put a circle of cones around his vehicle to hopefully protect it. After a while, he realized that drivers were treating it essentially as a roundabout. So he set up lane closures to bring it to a single lane (with a right turn bypass!) The aforementioned traffic engineer then took the idea and modified it a few times to make it work better. They implemented it at two other intersections. One of those had about a five mile backup which became about a ½ mile queue after the temp roundabout was implemented.