PennDOT plans on Tuesday to open the new Diverging Diamond interchange along Interstate 70 in Rostraver to two lanes of traffic in each direction on Route 51.

The interchange was partially opened in July, with a single lane of Route 51 traffic crossing above the interstate in each direction.

On Monday, crews from Golden Triangle and Power Contracting will prepare for the opening of all Route 51 lanes by making final changes to the interchange’s traffic signals.

All lanes are expected to be cleared for traffic at about 5 p.m. Tuesday.

Motorists should be prepared for delays and intermittent traffic halts both Monday and Tuesday, when the signals will undergo testing of their emergency preemption function. That function provides a green light for approaching emergency vehicles.

Police will assist with stopping traffic while local police and fire departments test the signals’ operation.

In the diverging diamond format, which replaced a previous cloverleaf interchange, the northbound and southbound lanes of Route 51 cross over and swap positions at each end of the bridge. That allows motorists who are turning left from Route 51 onto I-70 to do so without having to complete the move in front of oncoming traffic.

The interchange work is part of a $120.6 million project that also involves improvements on an adjacent stretch of I-70.

Work along the interstate will continue into the winter, according to PennDOT. Crews will be reconstructing pavement, improving drainage and working on the median and shoulders.

Copyright ©2025— Trib Total Media, LLC (TribLIVE.com)