CORAOPOLIS (KDKA) — After decades of problems in the S bends of Interstate 79 just south of the Ohio River Penndot has a new plan of action to stop the rollover accidents.

PennDOT says the number of hours that drivers have lost sitting in miles of backups when an accident has happened could have been avoided if drivers, mostly truckers, had heeded the warnings to slow down to 45 miles per hour.

READ MORE: Pittsburgh's Dolly Parton Imagination Library Sends 75,000th Free Book To Pittsburgh Children

Penndot District 11 Traffic Engineer Todd Kravits says those curves are “Averaging about six rollover crashes per year, three of those would involve trucks on an average.”

Do the math back to when those curves opened in the mid-’70s and that’s a lot of trouble.

Static signs have been put up over the years but this latest effort is electronic, big, bright, and hard to ignore.

“When the trucks exceed that posted speed of 45 miles an hour,” Kravits said. “The message on the boards change, telling the trucks to slow down. In fact, it flashes trucks slow down and yellow lights flash as well.”

READ MORE: West Virginia To Study Need For Third Dose Of COVID-19 Vaccine

The new signs are connected to radar guns.

“The sensors are very very specific and they can detect different types of vehicles,” Kravits said. “In fact, we can set the system up to detect almost any kind of big one. Right now we have it focused on trucks.”

The electronic warning signs are both north and southbound.

The signs went active on Friday and so far some truck drivers appear to be taking the warning and slowing down.

MORE NEWS: Residents Get Married At UPMC Asbury Heights Senior Living Center

Penndot hopes the signs work because Kravits says while they have looked at engineering alternatives to eliminate the S-Curves, “other options right now that really aren’t feasible.”