The Triangle's first diverging diamond interchange opened before 9 a.m. Tuesday on Western Boulevard at Interstate 440 in west Raleigh.
The new design was scheduled to open Monday morning, but Western Boulevard was closed an extra day after the contractor delayed work, such as paving and putting down line markers, according to the N.C. Department of Transportation.
Other WRAL Top Stories
According to the DOT, the contractor, Lane Construction, faces $10,000-an-hour fines for missing the deadline. By Tuesday morning, the fine had topped $250,000.
The diverging diamond interchange is more efficient and safer, according to project engineers. The DOT posted an example of the interchange on YouTube.
How it works
Western Boulevard traffic turning right onto the interstate will remain in the right lane. Traffic traveling straight through the interchange or turning left will stop at a signal. On green, those drivers will be able to make a left turn onto the ramp without having to cross oncoming traffic or continue straight ahead.
A national study of diverging diamond interchanges found that the design reduced crashes resulting in injury or death by an average of 54 percent.
The diverging diamond interchange is also less expensive than other interchange redesigns because it often can use existing infrastructure. The DOT has installed several diverging diamonds in other parts of the state, including in Mebane and Lumberton, and says more are planned for interchanges in the Triangle.
The I-440 work is part of a project to widen the interstate to a total of six lanes between Walnut Street in Cary and Wade Avenue in Raleigh.
That work is scheduled to be completed in summer 2023.