SECAUCUS — A year after state and local dignitaries broke ground on a $1.5 billion rail bridge in the Meadowlands, NJ Transit and Amtrak commuters aren't yet riding on the new span. But they are passing an active construction site.

Tucked away under the Eastern Spur of the New Jersey Turnpike, several sections of two giant steel support poles await installation. They will carry high-voltage electrical transmission lines that power the railroad. When put together later this month, they will tower more than 200 feet.

"The equipment we will use to lift these things is truly epic," said Scott Clinton, Amtrak manager of capital construction. "There's a lot of moving pieces."

Nearby, a small army of construction workers in hard hats and safety vests pour concrete into a 540-foot retaining wall. As they do, NJ Transit and Amtrak trains carefully slip by at 30 mph, half the usual speed, and blaring their horns, to protect the safety of the workers.

The retaining wall will support the eventual alignment of the new tracks that will take these same trains to the new Portal North Bridge.

That span will be the centerpiece of a 2.3-mile project that will allow trains to pass at 90 miles an hour over the Hackensack River, with enough clearance below to allow for maritime traffic. The current bridge, built in 1910, occasionally gets stuck in the open position, and Amtrak personnel have to bang it closed with sledgehammers.

As the smaller projects show, there's more to building a new bridge than just the bridge.

"It's not like we're just replacing a few hundred yards of span," said Craig Schulz, an Amtrak spokesman for the Gateway Program. "It's a pretty extensive project."

The new bridge will offer some relief to beleaguered commuters. However, the federal government still hasn't committed to pay for nearly half the project's total cost.

Late last year, right after the ceremonial groundbreaking, the Federal Transit Administration downgraded the Portal North project's eligibility for the agency's Capital Investment Grants.

NJ Transit responded by committing $600 million in borrowed money backed by revenues from the state Transportation Trust Fund. The federal agency is reviewing the plan, and a decision could come early next year.

"Hopefully, we can just keep it going," Schulz said.

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Meanwhile, a $16 million federal grant, with a $4 million state match, is paying for the work that's underway, and it will be finished in time for what the project's supporters hope will be a favorable ruling from Washington.

Clinton noted that the early construction work he oversees is on schedule and under budget.

“The steady progress on early construction work on the Portal North Bridge is proof positive that the Gateway partners have the skill and will to deliver projects on time and on budget," said Jerry Zaro, New Jersey's trustee on the Gateway Development Corp., which is overseeing the work on the bridge.

The bridge is but one piece of the larger, $30 billion Gateway Program to rebuild and expand rail infrastructure between Newark and Manhattan.

The larger effort will include a new Hudson River tunnel with two tracks. The current two-track tunnel, built in 1910, will be rebuilt. Its condition has worsened since Superstorm Sandy flooded it with seawater in 2012.

Other work includes a direct connection between the Bergen, Main and Port Jervis lines and the Northeast Corridor to enable a one-seat ride from Bergen and Rockland counties into New York.

Another bridge, Portal South, will expand the railroad to four tracks from Newark to New York Penn Station.

But funding for all those pieces is far from secure. The Trump administration has balked at paying for half the tunnel's estimated $13 billion construction cost and has thrown up hurdles toward getting funds for the Portal North Bridge.

For now, the work focuses on smaller pieces of the project. In addition to the electrical transmission poles and the retaining wall, workers have relocated a bundle of fiber-optic cables that connect to Wall Street. The cables were attached to the current bridge.

They've constructed a steel cage around a Civil War-era cast-iron pipe that still provides two-thirds of Jersey City's water. That structure will shield the ancient pipe from the daily march of heavy trucks and construction equipment.

"We're obliged to provide some protection for their infrastructure from our equipment," Clinton said.

At the retaining wall, which runs parallel to the NJ Turnpike and is within sight of Secaucus Junction, workers have installed most of the 206 precast concrete panels.

The concrete they're using to fill in the space behind the panels isn't the kind you'd use to pave your driveway. It's cellular concrete, which is lightweight and porous.

Proper drainage of water away from the track surface is critical to a functioning railroad, Clinton said, and the cellular concrete does the job well.

The new track alignment west of the Secaucus station will rise dramatically over the landscape on a 2 percent grade. That's a 2-foot rise for every 100 feet of track, and it will allow the new bridge to clear any barges on the river. The current alignment will be abandoned.

Clinton said the project has uncovered pieces of the old New York Penn Station, which was demolished by the financially distressed Pennsylvania Railroad in 1963 and unceremoniously dumped in the Meadowlands. He said that as construction progresses, more discarded pieces of the station may turn up.

Unlike the construction of the Pennsylvania Railroad in 1910 or the turnpike in 1951, today's workers can't just build the new bridge without taking the environment into consideration. They're bound by the National Environmental Policy Act of 1969. That landmark law requires extensive review of environmental impacts and mitigation.

"When we're all done," Clinton said, "we're going to put things back the way they were."

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