The massive rail bridges over 52d Street in West Philadelphia are a portrait of neglect.
Trees grow from their ramparts, water weeps through their stone walls, holes are visible in the rusting deck, the piers are cracked, beams are corroding. Trash gathers at the base of the columns.
Every day, scores of trains and thousands of passengers cross the bridges on five sets of tracks. Amtrak trains run there between Harrisburg and Philadelphia, and SEPTA's busiest route, the R5-Paoli line, passes over.
The 108-year-old structure is a key span on a route the Obama administration is considering for a high-speed rail corridor that could carry 125-m.p.h. trains.
But like many Amtrak bridges in the Philadelphia region, the 52d Street structure is made of corroded steel and crumbling stone.
Amtrak inspectors rate many of its structural elements "poor." Some components are even worse, marked "serious," just one grade above "failed."
Nearly half of Amtrak's 302 bridges in the Philadelphia region have some elements rated "poor" or worse, according to Amtrak's bridge-inspection reports, prepared over the last two years. The Inquirer obtained them under the Freedom of Information Act.
The inspections show that 143 bridges - 47.4 percent - received "poor" or lower marks for such defects as deteriorated metal plates or decaying stone walls. Some have eroded support piers, others badly worn girder elements and missing rivets. (The count does not include marks for painting or signs, which would push the number of "poor" structures even higher.) None of the bridges had any "failed" marks.
Amtrak officials say the bridges remain safe for travel. But decades of deferred maintenance mean the aging bridges will require hundreds of millions of dollars to bring them into good repair.
The situation is similar elsewhere in the country, where Amtrak owns about 1,400 bridges, largely in the Northeast. Lacking money to meet all of its repair and maintenance needs, Amtrak has deferred an estimated $5 billion in capital and infrastructure maintenance spending.
"In addition to increasing the risk of a major failure on the system, the deteriorated condition of Amtrak's rolling stock and infrastructure may contribute to higher operating costs and reduced reliability of service," the GAO said in a 2006 study, the last review of its kind by the agency.
Charles S. Yordy, Amtrak's director of structures, maintenance, and inspection, said the bridges, even in their present state of deterioration, remain safe for use.
"Our primary concern, first and foremost, is the safety of the traveling public," he said.
Accidents related to structural failure of rail bridges are relatively rare. Federal Railroad Administration records show that between 1982 and last year, 58 train accidents were caused by the structural failure of railroad bridges, all on freight railroads and none fatal.
In the Philadelphia region, many of Amtrak's bridges are more than 100 years old, inherited from the defunct Pennsylvania and Reading railroads. Built in the age of steam locomotives, the bridges were designed for heavier trains than they now carry.
"So we have some degree of reserve capacity," Yordy said. "You can have some reduction in material and not have a calamitous collapse." He said "rust looks a lot worse than it is."
Independent engineers, agreeing that poor ratings don't mean impending disaster, say the reports are warning signs of the need for prompt attention.
"Everything is of concern, but it's not necessarily earth-shaking," said Ben T. Yen, professor emeritus of civil engineering at Lehigh University and a consultant to companies and states on bridge evaluation and repair. "Every part of a bridge is important and needs to be maintained."
Decades of wear, rain, snow, road salt, and debris cause deterioration in bridge support structures.
Left unchecked, such deterioration can create major structural problems, similar to the cracks that required the emergency closing of I-95 in Philadelphia last year to reconstruct a column.
Bridges usually deteriorate very slowly, although collapses can occur suddenly when one element fails, as happened with an I-35 highway bridge in Minnesota in 2007. There, gusset plates that connect beams to columns buckled and triggered a collapse that killed 13 people.
The 302 Amtrak bridges in the region are all in Philadelphia and its four suburban Pennsylvania counties, as there are no Amtrak-owned bridges in South Jersey.
On most of them, according to the reports The Inquirer obtained, structural elements typically were rated "fair," or 3 on a scale of 1 ("excellent") to 6 ("failed"). Each bridge is inspected annually, and a rating of 4 ("poor") or worse prompts a follow-up inspection by an Amtrak system engineer to determine what action is needed.
As a result, 111 local bridges - including those over 52d Street - have been put on a priority list for repairs or replacement, with an estimated cost of $19.4 million. But many of those will wait years for attention because of a lack of money.
The current Amtrak capital budget has only about $38 million for bridges, culverts, and tunnels nationwide, down 34 percent from the 2008 budget.
More money is on the way. In October, Congress roughly doubled its contribution to Amtrak, approving $13 billion over five years. The federal stimulus package also included $1.3 billion for capital investment for Amtrak. None of that money is earmarked for bridges in the five-county Philadelphia region.
Tony DeSantis, president of the Delaware Valley Association of Rail Passengers, said, "There has been no massive rebuilding since the '30s."
"I don't think you need to sit up nights worrying about bridges collapsing, but they need to get on this, in terms of fixing and maintaining and replacing them," he said. "You can't run a passenger railroad unless you have infrastructure in good repair."
On Amtrak's Philadelphia-area bridges, elements rated "poor" or "serious" vary widely, depending on the type of bridge. Many have deteriorated sole plates (a support member for a beam) or masonry plates (which spread the load to underlying concrete or stone foundations).
Some have corroded anchor bolts, which connect the bearing to the columns. Some have deteriorated walls, where the end of the bridge rests. Some, like the Pennsylvania Avenue bridge in Morrisville, have excessive movement when trains pass over.
Many have multiple woes.
A report on a steel bridge over Allegheny Avenue in North Philadelphia notes: "Bottom flange reduced to a knife's edge at [end of bridge]. Masonry and sole plates are reduced significantly due to heavy rusting. Two stiffeners [steel supports] above abutment are reduced. Back wall shows heavy spalling [crumbling] . . . rivets worn at connector plate . . . handrail at south end is loose."
At a stone-arch bridge over Whitford Road in Chester County, the inspector noted missing bricks, leaving holes and cracks, and he wrote that "poor drainage is allowing water to penetrate . . . causing further deterioration."
At a concrete bridge over North 11th Avenue in Coatesville, the inspector reported 60 percent of the underside was deeply eroded, exposing rusting steel reinforcing bars.
The 92-year-old bridge over Anderson Avenue in Ardmore, next to the train station, has holes in the asphalt walkway through which the street below is visible. Part of the girder beneath the walkway, the inspector wrote, is reduced in half by rust, and a nearby strut is rusted through completely.
As bridge elements deteriorate, they can cause the rails to bend or shift, making trains slow down or even derail.
Amtrak's Yordy, standing under the 52d Street bridges, said that even with its litany of problems, the structure "is still serviceable." But he noted that its age was catching up with it.
"One-hundred-year-old bridges should be considered for replacement," he said, noting the corrosion and the possibility of steel fatigue.
As Yordy and Amtrak spokesman Cliff Black examined the structure recently, a pedestrian chastised them: "Why don't you paint it so it looks like something?"
Black looked at the rusting bridges overhead and acknowledged, "These are ugly, just as that guy said. But they are safe. They may need some remedial work. But one bad member won't bring them down."
With more bridges than money, Amtrak has a challenge to determine which repairs can afford to wait and which must be made now.
"The main thing is, we really have to pay attention to the minor things so they don't become serious," said Yen, the bridge expert at Lehigh. "Every part of the bridge must be maintained in good shape."