WASHINGTON - The collapse of the Interstate 35W bridge in Minneapolis is igniting politically charged calls for a remedy to the nation's aging road infrastructure, including tens of thousands of substandard bridges.
As federal and state leaders ordered emergency inspections of similarly designed bridges, Democrats sparred with the White House on Thursday over responsibility for what both sides say is growing trouble on America's roads.
The debate played out as Congress was poised to set aside $250 million in emergency funding to help the Twin Cities recover from Wednesday's catastrophic bridge collapse.
On Thursday federal officials alerted states to inspect all bridges similar to the 35W bridge. In Minnesota, attention turned to the 200-plus bridges that share a well-known design weakness also in the 35W span -- a lack of structural redundancy.
The 35W bridge, like many others around the nation, had at least one steel component under tension whose failure likely would mean collapse. Civil engineers call such bridges "fracture critical."
Investigators still haven't determined whether that design weakness played a role in Wednesday's collapse. Gov. Tim Pawlenty on Thursday ordered immediate inspections of three Minnesota bridges of similar design. The bridges are on Hwy. 23 over the Mississippi River at St. Cloud, Hwy. 124 over the Kettle River at Sandstone and Hwy. 243 from Minnesota over the St. Croix River to Osceola, Wis.
In Washington, members of the Minnesota delegation readied two bills - one each in the House and Senate - that would authorize up to $250 million for the repair and reconstruction of the 35W bridge.
The emergency relief was sponsored by Rep. Jim Oberstar, the Minnesota Democrat who took control of the House Transportation and Infrastructure Committee at the beginning of this year.
Coleman, Klobuchar team up
In the Senate, Republican Norm Coleman and Democrat Amy Klobuchar teamed to sponsor an identical bill, which they said would pave the way for separate votes to spend the money in the coming months.
President Bush, in a White House appearance to discuss the 35W disaster, pledged that "the federal government must respond and must respond robustly."
But the bipartisan comity on the Minnesota aid masked deep divisions over the condition of the nation's bridges, nearly a third of which have been found structurally deficient or "functionally obsolete," according to recent studies by the U.S. Transportation Department and the American Society of Civil Engineers.
"I will say this is a reminder to us all that we need to have strong funding in the long term for our infrastructure needs in this country," Klobuchar said.
Oberstar said there are 592,473 bridges on the federal aid highway system. Of those 75,621 are structurally deficient and 79,523 are functionally obsolete. "These bridges do not have the capacity to carry the traffic that goes across," he said. "So we have a national bridge problem. This is part of our national highway problem."
None of the three Minnesota bridges that Pawlenty ordered inspected has the added concern of being "structurally deficient" -- a reference to their condition -- as the collapsed 35W bridge did. The bridges are rated in adequate condition, according to a Star Tribune analysis of the data in the National Bridge Inventory database as of February.
Yet the state has about 100 other bridges with nonredundant, fracture-critical components, which also are rated "structurally deficient," the data show. Of those, seven -- including the collapsed bridge -- are rated as possibly needing replacement.
The biggest is the Lafayette Bridge on Hwy. 52 in St. Paul.
"If one of the main beams fails in the system," said city engineer John Maczko, "the bridge is likely to collapse because there is nothing to take the extra load."
Such bridges are inspected at least once a year to check for fractures that could trigger a failure. But Maczko said he will be happy when the bridge is replaced, now scheduled for 2009. "The new codes have redundant systems in them, so that if one member fails another can hold it."
He said he wishes another fracture-critical bridge -- on I-35E over Cuyahoga Street -- would be replaced sooner than 2013 as currently planned.
State bridge engineer Dan Dorgan said that when the bridges now considered fracture critical were built in the 1960s, fatigue that could lead to such failure was not considered a problem in bridges. In the mid-1970s, engineers across the country started seeing problems in the design, he said.
Prof. Roberto Ballarini, head of the University of Minnesota Civil Engineering Department, said that bridges lacking structural redundancy are not necessarily bad, but require monitoring and maintenance. Adding redundant steel supports, for example, can affect other important bridge features, including how the structure expands and contracts, he said.
37 in state may need replacing
Minnesota has 37 bridges on federal and state highways labeled structurally deficient and possibly needing replacement. Throw in county road bridges and the number jumps to 460.
The data analyzed by the newspaper were contained in the Federal Highway Administration's National Bridge Inventory database as of February. The paper obtained a copy of the database from the National Institute of Computer Assisted Reporting in Columbia, Mo.
The U.S. Department of Transportation said Thursday that a label of "structurally deficient" means that certain elements of the bridge must be monitored and possibly repaired. "The fact that a bridge is 'deficient' does not imply that it is likely to collapse or that it is unsafe," the agency said in a prepared statement.
The debate over the backlog in bridge maintenance brought up finger-pointing in Washington over transportation spending. In his comments on the 35W collapse, Bush also used the occasion to rip Democrats in Congress for failing to finish work on the government's spending bills for the coming year, including an annual transportation appropriations bill.
He faulted the Democrats for exceeding his spending targets, prompting a sharp response from Senate leaders who accuse the White House of underfunding the nation's infrastructure needs.
"And when we try to invest what we believe is a better number, we just get veto threats," said Sen. Patty Murray, D-Wash., chairwoman of the transportation appropriations subcommittee.
Congressional Democrats and Republicans have been feuding since last month over an Office of Management and Budget report projecting a $4.3 billion shortfall in the federal Highway Trust Fund by the end of 2009.
Oberstar said that the Bush administration's unwillingness to commit to a "robust" transportation budget has led to the neglect of the nation's infrastructure, specifically bridges.
In 2003, the House Transportation Committee sent Bush a $375 billion transportation bill -- about $100 billion short of what the American Society of Civil Engineers recommended. Bush allocated $247 billion -- $90 billion less than the Transportation Department and the House committee passed.
Reporters Laurie Blake, Pat Doyle and Myron P. Medcalf contributed to this report.