Interesting dialogue as I am in Middletown WI this week, and low and behold I came upon an identical (to the Meridith) structure. But the big difference is that the size of the circle is 1.5-2X the one in NH
. When I say identical, right down to the center island design and granite curbs. My suspicion is that this design is a standard highway design (prehaps someone can find it in the DOT database) that NH DOT has lifted. The larger structure here seemed to work well with Semi's ( I saw 2 go arround both 90 and 180 degrees of the circle) with out hitting either the inside island or curbs.