An analysis of the recently released 2014 U.S. Department of Transportation National Bridge Inventory database finds good news and bad news when it comes to the most heavily traveled U.S. bridges.

The good news is that there are 168 fewer structurally deficient structures in Pennsylvania than there were in 2013.The bad news is that it means 61,000 structurally deficient bridges across the nation are still in need of significant repair.The analysis of the federal government data, conducted by American Road & Transportation Builders Association Chief Economist Dr. Alison Premo Black, shows cars, trucks and school buses cross Pennsylvania's 5,050 structurally compromised bridges 16.1 million times every day.Not surprisingly, the most heavily traveled are on the Interstate Highway System, which carries the bulk of truck traffic and passenger vehicles.The top 10 most heavily traveled structurally compromised bridges in the state are:• Parkway East over the Squirrel Hill Tunnel (Allegheny County)• PA Turnpike (Interstate 276) over Route 2017, DB-146 and DB-146 W (Montgomery County)• Delaware Expressway over Wheatsheaf Lane (Philadelphia County)• Delaware Expressway over Venango Street (Philadelphia County)• Interstate 95 over earth fill and sewer access (Philadelphia County)• Interstate 95 over Comly Street (Philadelphia County)• Interstate 95 over Unruh Avenue (Philadelphia County)• Interstate 95 over Fraley Street (Philadelphia County)• Interstate 95 ramp over New State Road and a railroad (Philadelphia County)• Interstate 95 over Ramp C (Philadelphia County)The bridge problem could get a whole lot worse soon, Black warns.The federal Highway Trust Fund is the source of 52 percent of highway and bridge capital investments made annually by state governments.The HTF has suffered five revenue shortfalls between 2008 and 2014, and has been bailed out with nearly $65 billion in revenues from the General Fund just to preserve existing investment levels.The latest extension of federal highway and transit funding through the HTF expires on May 31, absent congressional action. Nearly a dozen states so far have canceled or delayed road and bridge projects because of the continued uncertainty over funding.ARTBA expects that number to increase as the deadline nears."State and local governments are doing the best they can to address these significant challenges, given limited resources," Black says.Bridge investments have been growing in recent years, Black says, but it has come at the expense of highway and pavement spending, which has dropped over 20 percent in the last five years."Without additional investment from all levels of government, our infrastructure spending will be a zero-sum game," she said, noting that there is a current backlog of over $115 billion in bridge work and $755 billion in highway projects, according to U.S. DOT data."Many of the most heavily traveled bridges are nearly 50 years old. Elected officials can't just sprinkle fairy dust on America's bridge problem and wish it away," Black said.Bridge decks and support structures are regularly inspected by the state for deterioration and are rated on a scale of zero to nine-nine being "excellent" condition.A bridge is classified as structurally deficient and in need of repair if its overall rating is four or below.While these bridges may not be imminently unsafe, ARTBA believes signs should be posted so the public understands they have structural deficiencies that need repair.The ARTBA also found:• Pennsylvania ranks first place nationally in the number of structurally deficient bridges: 5,050.• Pennsylvania ranks second place in the percentage of its bridges that are classified as structurally deficient: 22 percent.