A bumpy half-mile missing link on the North Shore Trail will be filled handsomely this winter by a $5 million elevated structure stretching from near the 31st Street Bridge to the Three Rivers Rowing Association's boathouse in Millvale.

The trail addition "is actually one long bridge along the riverbank," said Thomas E. Baxter IV, executive director of Friends of the Riverfront, the nonprofit organization that sponsored and championed the project.

The addition is part of a $21.9 million Pennsylvania Department of Transportation project to relocate railroad tracks running parallel to Route 28 to clear the way for a major reconstruction and widening of the highway.

The project will begin soon with completion of the trail bridge scheduled for April. There will be no closure of the biking and hiking trail during the project, Mr. Baxter said. "We did not want to cut anyone off who commutes or uses the trail for recreation," he said.

Until now, riders on the North Shore who wanted to continue to Millvale had to endure a rutted half-mile unimproved section across Norfolk Southern Railway property between the entrance to the Washington's Landing bridge and the boathouse.

The project calls for moving the railroad tracks closer to the river, on the course currently used by trail patrons. The trail will occupy a 12-foot-wide elevated structure built over the edge of the riverbank.

Mr. Baxter said the structure will be above the 100-year flood plain. It will be wide enough to accommodate emergency vehicles. Because the structure will be built before rail lines are moved, there will be no need to close the trail during construction.

The completed trail structure will be taken over by the City of Pittsburgh and be part of the Three Rivers Heritage Trail, a dedicated biking, hiking and walking trail running 21 miles along both sides of the Allegheny, Monongahela and Ohio rivers.

Mr. Baxter said public meetings will be held next year on plans to extend the trail along the Allegheny to Armstrong County. Long-range plans also call for connecting various pieces of existing trail to form a Pittsburgh-to-Erie bikeway.

Moving the railroad tracks is a key to PennDOT's plan to improve the notorious Route 28 "death stretch" from Chestnut Street to the 40th Street Bridge.

The relocation project is funded through the federal economic stimulus program. The trail improvement got $2.9 million in stimulus money, $1.5 million from earlier federal earmarks, $500,000 from the state Department of Conservation and Natural Resources and $100,000 allocated by state Sen. Jim Ferlo, D-Highland Park., Mr. Baxter said.

The Heinz Endowments and Laurel Foundation provided $300,000 in support funding, he said.

The railroad relocation project is scheduled for completion in spring 2012. Minor restrictions may occur on Route 28 and River Avenue and a full closure of the 31st Street Bridge for about one month will be required as the project continues, PennDOT said.

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