A major interchange is undergoing a role reversal in Arizona's second- largest metropolitan area. Designed to solve traffic headaches and a dire safety problem, the Interstate 10 interchange project in Tucson is "flipping" the grade of Prince Road so that it will pass over, instead of under, I-10.
The revamp is part of a $76.4-million effort to widen I-10 along a two-mile stretch to eight lanes from six. Crews have to contend with six lanes of traffic at all times, a major railroad route and multiple utilities—all while keeping an eye out for potential archaeological finds.