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Many of the bridges included in the AP review have sufficiency ratings
-- a score designed to gauge the importance of replacing the span -- that are much lower than the Skagit bridge. A bridge with a score less than 50 on a 100-point scale can be eligible for federal funds to help replace the span. More than 400 bridges that are fracture critical and structurally deficient have a score of less than 10, according to the latest federal inventory. The Brooklyn Bridge is among the worst. There are wide gaps between states in historical bridge construction and their ongoing maintenance. While the numbers at the state level are in flux, Iowa, Nebraska, Missouri and Pennsylvania have all been listed recently in the national inventory as having more than 600 bridges both structurally deficient and fracture critical. Pennsylvania has whittled down its backlog of structurally deficient bridges but still has many more to go, with an estimated 300 bridges in position to move onto the structurally deficient list every year if no maintenance is done. Barry Schoch, the state transportation secretary, said in an interview that officials would like to add redundancy to fracture critical bridges when they can, particularly if a bridge is also structurally deficient. "Those are high on the priority list," Schoch said. After the 1983 collapse of the I-95 bridge over the Mianus River in Connecticut, the focus turned to a fracture critical bridge style known as pin-and-hanger assembly. Pennsylvania worked over the following years to add catcher beams to its pin-and-hanger spans. That's the case now on the George Wade Bridge that carries I-81 traffic across the Susquehanna River. More recently, crews have also been trying to move the bridge off the structurally deficient list after finding significant cracks in the piers. Officials say northeastern states face particular challenges because the infrastructure there is older and the weather is more grueling, with dramatic and frequent freeze-thaw cycles that can put stress on roads and bridges. Many Pennsylvania lawmakers have long sought to boost transportation funding, in part to address crumbling bridges. But this year's proposals, including Gov. Tom Corbett's $1.8 billion plan, stalled amid fights over details. That's a common issue among infrastructure managers in other states, who say they don't have the money to replace all the bridges that need work. Instead, they continue to do patch fixes and temporary improvements. Washington's Douglass bridge has been rehabilitated twice. The catcher beams were added because the pin-and-hanger expansion joints that hold the bridge's main girders in place had deteriorated to the point "we were concerned that we could have a failure, and that the failure could be catastrophic," said Ronaldo Nicholson, the chief bridge engineer for the area. "If the joint fails, then the beam doesn't have anything to carry itself because there are only two beams. Therefore the bridge fails, which is why we call it fracture critical," Nicholson said. The bridge has a sufficiency rating of 60, an increase from the 49 rating in 2008 before some repair work was done. It remains structurally deficient because inspectors deemed the superstructure in poor condition due to "advanced structural steel section loss with holes and overhang bracket connection deficiencies," according to an inspection report from earlier this year. A new bridge would cost about $450 million if it was required to be able to open so large ships can travel the Anacostia, an infrequent occurrence, Nicholson said. If not, the cost could be as low as $300 million, he said. Nicholson emphasized that if city officials feel the bridge is unsafe, they'll prohibit trucks from crossing or close the span entirely. Inspections have been stepped up to every six months instead of the usual two-year intervals for most bridges. In the meantime, officials are trying to stretch the bridge's life for another five years
-- the time they estimate it will take to build a replacement. Congressional interest in fixing bridges rose after the 2007 collapse in Minneapolis, but efforts to add billions of extra federal dollars specifically for repair and replacement of deficient and obsolete bridges foundered. A sweeping transportation law enacted last year eliminated a dedicated bridge fund that had been around for more than three decades. State transportation officials had complained the fund's requirements were too restrictive. Now, bridge repairs or replacements must compete with other types of highway projects for federal aid. The new law requires states to beef up bridge inspection standards and qualifications for bridge inspectors. However, federal regulators are still drafting the new standards. "Do we have the funding to replace 18,000 fracture critical bridges right now?" Rehm asked. "No. Would we like to? Of course."
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