Across the state and in the region, a bad bridge situation has gotten better in recent years.
Although Pennsylvania continues to lead the nation in structurally deficient bridges, the number of state-maintained bridges in that category has fallen from 5,600 in August 2010 to fewer than 4,500 in the most recent count.
Similar progress has been made locally. In a five-county area that includes Pittsburgh, the number of deficient state- and locally maintained bridges has fallen from 1,246 in 2010 to 1,054 now. In Allegheny County, the number was reduced from 439 to 340 in that time.
Still, nearly a quarter of the bridges in Allegheny, Beaver, Butler, Washington and Westmoreland counties remain structurally deficient, a designation that does not mean they are unsafe but that they are showing signs of deterioration that, if unaddressed, could lead to weight limits or closings.
A bridge is so designated if any of three elements -- superstructure, substructure or deck -- is found by inspectors to be in poor or worse-than-poor condition.
Pennsylvania Department of Transportation officials warn that the trend toward better bridges will be reversed if the Legislature does not approve new funding sources this year.
"While we've been able to make progress over the past four years, it was because of additional money that no longer exists," said Dan Cessna, PennDOT district executive for Allegheny, Beaver and Lawrence counties. That included the federal stimulus program and a state bond issue during the administration of Gov. Ed Rendell that was devoted solely to fixing bridges.
PennDOT projects that it can further reduce the number of deficient bridges to about 3,700 by 2020 if Gov. Tom Corbett's plan to raise additional transportation funding is approved. If nothing is done, it estimates the number increasing to about 4,800 by 2020.
About 300 bridges statewide are added to the structurally deficient list each year, including about 30 in Allegheny County, Mr. Cessna said.
One of the biggest bridges on the deficient list, the Liberty Bridge in Downtown Pittsburgh, is in need of rehabilitation that will cost an estimated $40 million to $60 million, he said. Final design of the project is expected to begin this year but construction funding is not yet available. More than 16,500 vehicles use the bridge on an average day.
The bridge superstructure is marred with patches of rust and there are areas of corrosion and deterioration in the steel, but Mr. Cessna said the span is safe. It is currently undergoing an in-depth inspection.
The best-case scenario has rehabilitation starting in 2015 if funding becomes available. The department will make interim repairs as necessary until then, Mr. Cessna said.
Other heavily traveled deficient bridges that are not funded for major upgrades yet are on Washington Avenue over Chartiers Creek in Bridgeville; Baum Boulevard over the Martin Luther King Jr. East Busway; and Golden Mile Highway over Humms Run in Plum. Together, they carry more than 50,000 vehicles per day.
Among the other major bridges that PennDOT would like to rehabilitate but lacks funding are the Birmingham and Smithfield Street bridges in Pittsburgh, the Elizabeth Bridge on Route 51 and the Vanport Bridge on Interstate 376 in Beaver County.
Projects that are scheduled to start this year will replace or rehabilitate three of the most heavily traveled deficient bridges in the county.
The Hulton Bridge over the Allegheny River between Harmar and Oakmont will be replaced by a new $60 million to $80 million four-lane span to be built just upstream from the existing bridge. Little-noticed structures on Route 88 and West Carson Street also will be replaced.
Two statewide plans have been advanced for raising additional revenue for roads, bridges and other transportation modes. Both would remove a cap on the tax paid by gasoline wholesalers, possibly leading to increased pump prices.
Mr. Corbett's plan would generate an estimated $380 million in year one and $1.4 billion by the fifth year for state and local roads and bridges.
Legislation sponsored by state Sen. John Rafferty, R-Montgomery, also would raise most driver fees, including vehicle registrations and license renewals. It would bring in $1.4 billion for roads and bridges in the first year and $1.9 billion by year five.
PennDOT plans to release a report by late this month or early June with details of what projects would be funded with the increased transportation revenue.
Jon Schmitz: email@example.com or 412-263-1868. Visit the PG's transportation blog, The Roundabout, at www.post-gazette.com/Roundabout. Twitter: @pgtraffic. First Published May 20, 2013 4:15 AM