"It will be like a spaceship landed," warned Pennsylvania Department of Transportation spokesman Eugene Blaum. "Motorists should be aware it is going to be there so they can keep their eyes on the road."
Work on the bridge had barely begun at 10 p.m. Friday, however, when the traffic nightmare started. Reduced by one lane in each direction for the installation, the expressway was gridlocked throughout yesterday. Pennsylvania State Police said the traffic flow was unlikely to improve until the project is completed tonight.
More than 100,000 vehicles pass that way each weekday. But the $8.1 million span - owned by Norfolk Southern, paid for by PennDot - will be nowhere near as busy. It has one purpose and only one: to carry a single train, the ingot-lugging "Lukens Local," on a 31-mile round trip between Swedeland in Montgomery County and Coatesville in Chester County once a day, six days a week.
"Whether one train or 41 trains use it," Blaum said, the state had no choice but to build the bridge - if it wanted to proceed with the $240 million redo of the I-76 and Route 202 interchange at King of Prussia.
Norfolk Southern's old bridge, a 110-foot-long, steel-plate platform built in 1951, was squatting in the middle of the plans. It had to come down.
The line itself dates to 1889, when the rails ruled long-haul transport. Wanting to skirt the congested yards of Philadelphia, the Pennsylvania Railroad constructed what became known as the Trenton Cutoff, over which freight flowed from Trenton west through Montgomery, Chester and Lancaster Counties to Harrisburg and beyond.
Even in the 1950s, as the Pennsy waned, the line was carrying as many as 30 trains daily - serpentine monsters comprising 100 cars each and packed with coal, automobiles and general merchandise.
Today, the Trenton Cutoff is near dormant. Once a day, two six-axle locomotives coupled together push 30 to 40 cars loaded with scrap metal out of a small switching yard in Swedeland and trundle toward the Bethlehem Lukens Steel mill in Coatesville. On the return trip, they carry steel ingots.
"The fact that there is one train a day is the railroad's business," said Jack Claffey, director of transportation planning at the Delaware Valley Regional Planning Commission. Under state law, PennDot "can't come along and screw them."
Earlier this year, the old bridge was demolished, and Norfolk Southern switched to an adjacent, Peco-owned rail bridge. That, too, will be torn down when the new span opens, probably by March.
A half-mile away, over nightmarishly congested South Gulph Road, PennDot is spending $2.6 million to replace a 27-foot-long Norfolk Southern bridge with one that is 102 feet. Part of the same gargantuan King of Prussia project, South Gulph will be widened to include three traffic lanes and two bikeways.
The Lukens Local that chugs over both bridges might not be so lonely someday. Norfolk Southern is hoping to pick up more industrial customers along the swiftly developing Route 202 corridor in Chester County, said spokesman Rudy Husband.
One potential client looking longingly at the Trenton Cutoff is SEPTA. In planning documents, the transit agency has floated the idea of using the tracks for its proposed Cross County Metro commuter line, between Willow Grove and southern Chester County.
Norfolk Southern is not commenting on the prospect of sharing its rails with passengers.
The Cross County, after all, has generated little popular support and virtually no capital funding since it was first envisioned in the mid-1980s. It is, Husband said, "too far out to be meaningful."
To others, the bridge presents a more radical possibility: a landmark-size ad for suburbia.
Civic boosters already are salivating at the thought of slapping a message or greeting on the span, which will dominate a featureless edge city known for mall sprawl and office parks.
Like the famed "Trenton Makes the World Takes" bridge (1,022 feet) over the Delaware, "it should have something on it," said Peter Quinn, director of the Greater Valley Forge Transportation Management Association, a nonprofit clearinghouse for commuter services. "It should get a name."
"We might want to paint it" with a slogan, said Al Paschall, director of the Greater Valley Forge Chamber of Commerce. "We are the land of Mr. Mall," as he calls King of Prussia's retail megalopolis.
Not so fast, said Husband, of Norfolk Southern.
"We frown upon any kind of billboard or advertising on our structures," he said.
"If somebody wanted to put up a sign that said, 'Welcome to the Suburbs,' I'm not sure we would be open to that."
Contact Jere Downs at 610-313-8128 or firstname.lastname@example.org.