Construction season moves into high gear this morning with major changes in traffic patterns on Route 65 at the Interstate 79 interchange in Glenfield.

Restrictions and/or ramp closings also resume today on Route 28 at Etna and the Fort Duquesne Bridge, Downtown, as the Pennsylvania Department of Transportation begins nearly $300 million in road and bridge work in Allegheny County.

Weather permitting, crews were expected to start crossing southbound Route 65 traffic to the northbound side at 7 a.m. at River Road in Haysville. Single-lane traffic will be maintained in both directions on the northbound side through Toms Run Road in Kilbuck.

The $20.8 million project to improve the interchange and its Route 65 approaches began last year. Today's changes also will affect numerous ramps.

These ramps will be closed and traffic detoured: southbound Route 65 to southbound I-79; northbound I-79 off-ramp to southbound Route 65; Kilbuck Street on-ramp to southbound Route 65; southbound Route 65 off-ramp to Kilbuck Street/Glenfield Viaduct; and Glenfield Viaduct on-ramp to southbound Route 65.

Two ramps will have their direction of traffic reversed: On-ramp from Kilbuck Street/Glenfield Viaduct to northbound Route 65 will become the southbound off-ramp to Kilbuck Street/Glenfield Viaduct/northbound I-79; northbound off-ramp from Route 65 to Glenfield Viaduct/Kilbuck Street/northbound I-79 becomes the on-ramp from Kilbuck Street/Glenfield Viaduct to southbound Route 65.

Northbound traffic on Route 65 accessing Glenfield Viaduct/Kilbuck Street/northbound I-79 will be detoured.

In a statement last week, PennDOT said the process to complete the crossover and close and reverse the ramps is expected to take most of today. The new traffic patterns will remain in place around-the-clock through late June. Detours will be posted.

In June, traffic will be moved to the other side and restrictions will continue until October.

Big changes also are in store on Route 28, the Fort Duquesne Bridge and Parkway East, where a weekend project produced big outbound backups at the Squirrel Hill Tunnels on Saturday.

The ramp from Fort Duquesne Boulevard to the upper outbound deck of the Fort Duquesne Bridge will close starting at 7 a.m. today through April 9 as work resumes on a $23.3 million bridge rehabilitation project that will bring numerous restrictions through its completion in October.

Traffic will detour via the 10th Street Bypass, Commonwealth Place and Fort Pitt Boulevard to reach the bridge.

Route 28 will have single-lane traffic in both directions at the Etna interchange from 9 a.m. to 3 p.m. weekdays this week as crews prepare a construction crossover for next Monday.

Also, the on-ramp from Butler Street to southbound Route 28 will be closed starting at 9 a.m. today through late November.

Next Monday, northbound traffic will be reduced to one lane at the Shaler water plant and cross over to the southbound side for about one mile, returning to the northbound lanes before the new bridge over Route 8 at the Etna interchange.

Two southbound lanes of traffic will be maintained.

The crossover is needed to allow crews to reconstruct the northbound road surface and bridges, PennDOT spokesman Jim Struzzi said.

The $27.2 million project will complete more than 10 years of improvements to the Etna interchange.

Major reconstruction of the outbound Parkway East from Churchill to the Pennsylvania Turnpike is to begin next Monday, but drivers got a surprise appetizer on Saturday. Outbound traffic was restricted to one lane just before the Squirrel Hill Tunnels, causing backups of two miles or more through the day.

Mr. Struzzi said repairs were being made to the concrete connections to abutments on the Commercial Street Bridge and the restriction could not be lifted until the concrete cured. The work could not be performed overnight because of the cure time needed, he said.

It "was an odd set of circumstances with the Penguins game and people out and about because of the good weather," he said. "We apologize to the public for the inconvenience and the headaches it caused."

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