An unconventional design known as the diverging diamond interchange has proven to be safer and more efficient than conventional left turn lanes. Road planners across the country are switching sides.

APPLETON — In an effort to increase traffic safety, the Wisconsin Department of Transportation is constructing three new diverging diamond interchanges as part of the Interstate 41 expansion project.

Diverging diamonds quietly remake U.S. interchanges, easing left turns, crashes, and delays with smarter, human centered ...