Today is the day when the southbound Parkway North goes down to a single lane so that PennDOT can create the 579 crossover into the HOV lane for the next couple of months. 

PennDOT is trying to minimize the disruption to your weekend plans, and the expected confusion comes on Monday morning. 

The HOV lane entrances are closed, the lines have been repainted to make it two lanes, and in short, it is temporarily no longer an HOV lane. 

"It'll strictly be just for 579 traffic," said PennDOT District 11 Assistant Executive Director for Construction Doug Thompson. 

Thompson said they must get all of the 46,000 vehicles per day off of the southbound ramps to the Veterans Bridge. 

"We need to lift up the bridge and completely remove all the loading from that bridge to do some repairs and strengthen the bridge's substructure," Thompson explained. 

Removing the traffic also means that they'll be closing the ramp from Route 28 southbound to 579, and those 11,000 drivers per day will detour up to East Street Valley to access 579 with the 35,000 other daily drivers at the opening to the HOV lane south of McKnight Road. 

"Then both the center and left lanes, as we know them today, are available to go into 579," Thompson said. 

It will be a major change of driving habits, and Thompson said he believes that people will learn quickly, even if they miss it the first day, it's only a mistake drivers will make once. 

The Parkway North lane restrictions begin tonight at 9 p.m., they will reopen one of the lanes on Saturday so those heading into town for Pickesburgh can get in with minimal disruptions, and then go back into place on Saturday night at 6 p.m. 

The new configuration will be ready by 10 a.m. on Sunday morning and in place for the Monday rush hour and beyond. 

In total, between the north and southbound support piers, five bridges are considered high priority, and there are another 18 that need repairs. 

PennDOT expects to wrap up the repairs by early December.