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Time To Overhaul America's Aging Bridges?


This is SCIENCE FRIDAY; I'm Ira Flatow. Five years ago this month, the I-35W bridge in Minneapolis collapsed, sending a full load of rush-hour traffic into the Mississippi River. The disaster injured nearly 150 people, killed 13. The bridge was literally falling apart.

A year before the collapse, state inspectors found that some of the bridge's bolts were either loose, or corroded or missing altogether. In the words of one of my next guests: Engineers don't specify unneeded bolts. But how can we be sure something like that won't happen again? We probably can't, because experts say that nearly 8,000 bridges around the country are unsafe and in dire need of repair, similar in some way to the conditions on the I-35W bridge before it crumbled.

That doesn't mean they'll all collapse tomorrow, of course, but there's a great deal of uncertainty about their safety. You might be driving on one of them right now. And you can find out if one of those aging bridges is near you. You can go to SaveOurBridges.com, it's a site one of my guests, my next guest, has created to educate the public about our nation's infrastructure.

And let me introduce him now. Barry LePatner is the creator of SaveOurBridges.com. He's also author of "Too Big To Fall: America's Failing Infrastructure and the Way Forward." And he's founder of LePatner & Associates, that's a construction law firm here in New York. Welcome to SCIENCE FRIDAY.

BARRY LEPATNER: Ira, good to be with you today.

FLATOW: Also with us is Bill Miller, an associate professor of civil and environmental engineering at Temple University in Philadelphia. He joins us from Philly. Welcome to SCIENCE FRIDAY, Dr. Miller.

BILL MILLER: Thank you, Ira.

FLATOW: You're welcome. Dan McNichol is a journalist and author of "The Roads That Built America" and "The Big Dig." He's currently working on a book about the San Francisco Bay Bridge. He joins us from KQED in San Francisco. Welcome to SCIENCE FRIDAY, Mr. McNichol.

DAN MCNICHOL: It's great to be here, thanks Ira.

FLATOW: Bill, let me ask you about this bridge first. You're a civil engineer, and from an engineering perspective, what grade would you give the nation's bridges? Might there be bolts missing from a lot of bridges around the country?

MILLER: Certainly when the - based on when the interstate system started being built, back in the mid- to late '50s, at that time the standards for both building and constructing these types of larger bridges was not as well-developed as it is today. And that also includes the materials and the level of technology for making better steel and evaluating the designs by computer animation and those sorts of things we have today.

So based on that, yeah, certainly the inventory of bridges out there needs to be probably much more - inspected much more often than it actually is. But of course these are constrained by the state budgets for this type of purpose, since it's primarily the states that inspect and keep up the maintenance on these bridges.

FLATOW: And so what grades would you give in general, the bridges?

MILLER: Well, you can't give it an F because they're all standing up, but it's probably a D, barely functional, functioning not at an average level, but at a level which requires a lot of attention.

FLATOW: Barry LePatner, let's talk about the website you've created, SaveOurBridges.com. What criteria do you use to put a bridge on that site?

LEPATNER: Well, let me first say that I didn't create the criteria; the Federal Highway Administration was the one who provided, albeit without publication, the database here. There are 600,000 bridges on our national bridge inventory database, and what the Federal Highway Administration had prepared, never made public - I was able, doing research for my book "Too Big To Fall" to gain access to this database - was knowledge that with the fact that we have 72,000 bridges that are deemed structurally deficient, that means they're poor, that means you can't have the intended weight, and you have to close lanes on them.

But in addition to that, of those 72,000 bridges, there are 7,980 bridges that the Federal Highway Administration identified which were not only structurally deficient but fracture critical. And this is an important term for the public to understand. Fracture critical means they were designed in the '60s and '70s, so that if one member, one critical member fails, the entire bridge goes straight down. There's no redundancy to support the bridge.

Combine a bridge that's structurally deficient, poor, that is already lacking maintenance, with the fact that one piece can break, and it goes straight down, and you get the I-35W, you get the Sherman Minton Bridge that would have gone down but it was closed at the last minute, last October, in between Kentucky and Indiana.

And you understand that there are bridges, 160 on average in every state, just like those bridges.

FLATOW: So what's the goal of creating this map, for people to see where these bridges are and stay off of them?

LEPATNER: Well, as I went around the country and spoke to groups, from Washington to all over the country, the immediacy, the enormity of the problem that we're facing today with these perilous bridges almost washed over everybody's head. And so to bring it down to the community level, to make this a grassroots grasp of the situation, I created SaveOurBridges.com so anyone can go on the map in their location, wherever they are in any state, and see the bridges in their community which are truly dangerous for their children to go over on school buses every day, for their families to travel to and from work and for their communities to be exposed to a peril that now requires them to speak out to their politicians and demand the funding to fix these bridges.

FLATOW: Dan McNichol, you've written about the history of the interstate highway system. Give us a little historical context of how we got to where we are today with our bridges.

MCNICHOL: Well, it's interesting. It starts back in the 1920s. It was a golden era for road-building. And because of the Depression, it kicked, actually, into high gear, where bridge-building kept going, kept growing, despite the downturn in the economy.

But after World War II, Eisenhower, having driven his forces across the Autobahn, was so impressed, and when he became the president, very quietly but very quickly, he moved to develop a much broader system of road-building and networks. And he ousted the head of the Bureau of Public Roads at the time - today's Federal Highway Administration - because he wanted to create a new system, a new idea, a new concept, not improve the black-and-white-shielded highways, the U.S. routes like old 66, but he said let's build a brand new system just like the Autobahn, off to the side.

And that system became the red-white-and-blue-shielded interstate system. It was built, it was meant to be built in about 13 years, it was supposed to be done by the 1970s, early '70s, and it wasn't. It kept going. And the urban bridges, are the ones that are causing the most trouble today, were the last ones built, but they're the most heavily used.

The whole system, only not even two percent of our road net, handles 25 percent of our traffic. And these bridges were pretty much minimally designed, like Barry was mentioning, with a lifespan of maybe 40 years, but they were really disposable. They saw that the growth was coming so quickly that they would need to probably tear these things down and rebuild them anyway, just to expand them or increase their capacities.

So we're left with a whole inventory of bridges today, built in the '50s and the '60s and into the '70s, that are way beyond their lifespan; they've been beaten up and abused badly by trucking and heavy loads, and they've been neglected, mostly, by lack of maintenance.

FLATOW: Let me ask you about a bridge that's near to my heart because I cross over it every week. It's the Tappan Zee Bridge that crosses the Hudson, just north of New York City. And they're trying to build a new one because this one is in great danger, correct?

MCNICHOL: It is. And as a civil engineer student in your past, Ira, I'm curious what you think of it.


MCNICHOL: But it's an old, gorgeous truss bridge. I love these things like I think an engineer might. But the thing it, it was built in the early '50s. During the Korean War, a lot of bad metal was out there. And when this thing was put together, it was put together quickly in a spot that made political sense but not a lot of sense from an engineering standpoint, at a very wide part of the Hudson River.

And it has been the poster child of a road that's been overused and abused and neglected. And it is in dire need of a rebuild, a complete rebuild, and a replacement. And it looks a lot like this bridge out here in San Francisco, the Oakland Bay Bridge, that section between Oakland and Yerba Buena Island, that collapsed during the 1989 earthquake.

FLATOW: 1-800-989-8255 is our number if you'd like to call in. At what point does it pay to repair the bridge or to build a new one? Where...?

MCNICHOL: Well, in...

FLATOW: Anybody, you can all jump in. Go ahead, Dan, if you want to answer that.

MCNICHOL: OK, in 1989, that exact question, Ira, came to the Caltrans organization, the one that owned the Bay Bridge. And in '89 when the earthquake came and knocked out the Bay Bridge, they had this question: Do we rebuild it, or do we build a brand new one?

And the debate took so long. They decided, finally, to rebuild it. And that's what's being built today, a brand new, seismically advanced bridge. But it's almost a no-brainer. With the cost of repairing some of these old bridges, it's just simple and fast and more efficient to build a brand new one.

MILLER: Well, here's another aspect to look at it. In the year before the I-35W in Minneapolis collapsed, the Minnesota Department of Transportation was given a report by a prominent engineering firm, and it said that bridge is structurally deficient since 1991. It's fracture-critical. And with eight members that are in danger of collapsing, we recommend that we spend $15 million to shore up and provide redundancy to that bridge. The Minnesota Department of Transportation said that's a budget-buster, and we're not going to spend the money on it.

LEPATNER: They did spend three-and-a-half million dollars to do a pothole program on top of the bridge, loaded it up - against the advice of their engineers - with 575,000 pounds of material and trucks, right over the fracture-critical member, and it went straight down. The perverse reality of that was by failing to put up $15 million, the state got a brand-new bridge where the federal government pumped in $235 million. Multiply that by the nearly 8,000 remaining structurally deficient and fracture-critical bridges, and we could go broke putting in new bridges to replace old ones.

FLATOW: 1-800-989-8255. To the phones, to Roger in Philadelphia. Hi, Roger.

ROGER: Yes. Hi, Ira. Briefly, when the stimulus was passed in 2009, 787 billion, this could have - although we really need a few trillion to address the problem, as I'm sure your guests will agree. The stimulus money would have made a major dent in this, but it did not all get spent. I don't know what percent, but I think most of it was spent on other things than repairing infrastructure, even though very influential people like Ed Rendell, a former mayor and governor, whom I sure you're familiar with, were major advocates of infrastructure repair. And it seems to me that if you build it, you have a moral responsibility to maintain it, and yet the money just fritters away on other things. And I'm mystified by this. And if you and your guests have any comments...


ROGER: ...I'll be happy to listen, take them off the air.

FLATOW: Thank you, Roger.

LEPATNER: Well, let me answer this, because Ed Rendell would be the first one to say: While everybody in America heard about a $750 billion stimulus plan, only about $26 billion was scattered throughout the entire nation on infrastructure, and most of that went to new roads on short-term projects. Clearly, our American leadership has failed us by letting this situation persist over decades, and we need a renewed commitment, a renewed sense of political will to reinvest heavily in our infrastructure, which is the backbone of our commercial growth in the United States, our global growth around the world and our homeland security.

This is an American issue. It's not a Democrat, a Republican, a right-wing or a left-wing issue, but it's going to take the American people to rise up and demand it or it's not going to happen, because Washington will not make this investment on its own.

FLATOW: I'm Ira Flatow.

MILLER: You have to look at the...

FLATOW: Let me just jump in here and remind everybody that this is SCIENCE FRIDAY, from NPR. All right, Dan, was that you jumping in?

MILLER: It's Bill.

FLATOW: It's Bill. I'm sorry.

MILLER: If you look at the funding - and this was mentioned previously. If you look at the funding history, that's where the information is about how this has worked up to this point. When Eisenhower thought about getting the federal government to fund this new highway system, he had a problem of convincing Congress of doing that, and they came up with the idea of what's called a user fee, which today, unfortunately, is called the gasoline tax, where all the citizens would pay a small amount based on their gasoline purchases for what's considered to be a generally, publicly usable and important system, the interstate highway system.

But - and when the system was also built, it was built with 90 percent federal funding. But behind that was the idea that one of the advantages of building such a large system was that about three times the cost of the system would eventually be expended on maintenance of the system, which would be the province of the state governments and the - and all of the contracting and all of the support for that would have to come through the state governments. So the state governments would be spending this amount of money.

The problem, of course, is that in the decades since then, the will to fund at the state level has dropped off, and I think this is where the main problem is. The states are primarily responsible for the maintenance of these systems.

FLATOW: 1-800-989-8255 is our number. I'm just going to - there was an article recently about how - the symptom of all of this is even - the Capitol Dome has 1,300 cracks in it. And the Senate voted for - the Democratic-controlled Senate voted to repair it, and the Republican-controlled House didn't allocate any money to repairing it, and it's leaking and things. If you can't repair the Capitol Dome, I mean, the symbol - the great symbol of Washington, what hope is there for repairing - spending money to repair the bridges?

LEPATNER: Well, let me just say that having been down to Washington, having appeared before prestigious, very, very savvy groups from the Brookings Institution to many of the transportation agencies and lobbyists, they all agree the money is there to make substantial inroads in remediating our roads and bridges. The problem is that the politicians see no particular benefit to each of them in putting the money there because it's not something that they get a photo-op or they get a benefit that leads to their re-election. And the stratification of the politics in Washington, unfortunately, has held our infrastructure hostage, and there's no desire right now to seriously put money other than to keep it in the status quo, and that's going to lead to tragedies, unfortunately, in the years to come.

FLATOW: All right. We're going to take a break. We'll come back and talk lots more about saving our bridges with Barry LePatner, creator of saveourbridges.com, Bill Miller, associate professor of civil environmental engineering at Temple, and Dan McNichol, journalist and author of "The Roads That Built America" and "The Big Dig." Stay with us. We'll be right back after this break, talking about bridges. 1-800-989-8255. You can tweet us @scifri. We'll be right back.


FLATOW: This is SCIENCE FRIDAY. I'm Ira Flatow. We're talking this hour about the unsafe bridges around America, how to potentially avoid another disaster like the I-35W Bridge collapse, which occurred five - just about five years ago. My guests are Barry LePatner, creator of saveourbridges.com, also author of "Too Big to Fall"; Bill Miller, associate professor of civil and environmental engineering at Temple University in Philadelphia; Dan McNichol, a journalist and author of the "The Roads That Built America" and "The Big Dig." Our number: 1-800-989-8255.

Bill, the Commodore Barry Bridge in Philly and the new I-35W Bridge in Minneapolis have sensors on them to help engineers see if the bridges are unsafe. Tell us a bit about how that works.

MILLER: Yes. The sensors have been on the Commodore Barry Bridge for several decades now. There's about 500 of them. And what they do is that they are attached to different sections of the bridge, and when the bridge vibrates or moves, the sensors indicate that vibration. It's somewhat similar to a seismometer and an earthquake detection system. And when these signals are sent, they're gathered together by a computer, and it can provide a live animation, computer animation of the bridge as it's moving based on the traffic moving across the bridge, the loads on the bridge, also the wind load, which is a significant amount of pressure on the bridge. And it's - it can be used to monitor and to look for what may become more serious over time, problems with the structure.

FLATOW: 1-800-989-8255. A tweet from Christina Goldberg, who wants to know what's the worst bridge in America.


FLATOW: You're laughing, Barry. I'm going to let you answer it.

LEPATNER: The worst bridge will be the next one to fall. Look, here's some statistics to understand. You talked about the Tappan Zee Bridge. It is a bridge that carries 140,000 vehicles a day. New York state - the New York Thruway Authority, which manages that bridge, pays $100 million a year to keep it afloat. It is structurally deficient. It is fracture-critical just like the I-35W. And while they're planning to build a new bridge nearby, it's still going to take many years. The risk to every driver who goes over there every day is tangible.

In our nation, every engineer will tell you if you have a toxic mix of the 8,000 bridges that I'm talking about, structurally deficient and fracture-critical, no bridge engineer - and I've talked to the American Society of Civil Engineers at conventions and other engineering groups around the nation - no engineer can tell you that that bridge will be standing a day, a week, a month or a year later if it has that combination. It is the physics of the situation.

And the other statistic that all Americans should understand, these are not idle incidents. Since 1989, nearly 600 bridges throughout our states have failed. That doesn't mean they've all collapsed. Many of them did. But fail means if a bridge falls two feet or three feet below where it is, and they have to close it and do repairs, it's a failed bridge. And this is a serious situation that cannot be minimized.

FLATOW: Mm-hmm. Barry, you're writing your book about New York City's Williamsburg Bridge, and the lesson - and your lesson in how to handle a dangerous bridge.

LEPATNER: The comparison that I make in the first chapter of "Too Big to Fall" called - the chapter is called "A Tale of Two Bridges," parallels what happened in Minnesota, where they truly mismanaged - and that tragedy should never have happened, had they acted responsibly - with the situation in 1988 on the Williamsburg Bridge, which was in similar jeopardy when the transportation engineer, Sam Schwartz, acted as an engineer and, on his own, closed the bridge against huge political efforts to try and countermand him. He stood his ground. And in doing so, he saved the lives of countless people, because that bridge was only a short time, probably months away from collapsing. And it carried over 100,000 vehicles a day, plus subway lines that use that bridge coming from Brooklyn into Manhattan. That kind of responsible leadership is not evident in almost all the states today, where they have the bridges that are shown on the Save Our Bridges map.

FLATOW: Mm-hmm. Dan McNichol, are there laws about how often bridges have to be inspected?

MCNICHOL: Yeah. It's part of the funding, and you can always follow the money. But in the United States, the National Bridge Inspection Program was born out of the Silver Bridge collapse in the 1960s. When that bridge went down, it was on U.S. Route 35. It created such an uproar, a lot like the I-35W Bridge collapse in 2007. And with a loss of 46 lives, Lyndon Johnson took to the airwaves and said, we're going to be inspecting all of our bridges. And it developed into a policy, into a program that demands that at least every two years, a bridge is looked at. If it's fracture-critical, functionally obsolete, structurally deficient, that bridge is looked at even more often. And if it's robust and it's new, it might not be looked at quite as often.

But the bridge program is - it's a classic example. The head of Federal Highway at that time said, "This is how we operate. We learn. We build upon tragedy," quote-unquote. And that is engineering. That goes back to antiquity. Every time there's a failure, we learn. The Tacoma Narrows that sensationally ripped itself apart in swinging wind, the Silver Bridge, the Mianus River Bridge, the Schoharie Creek Bridge in New York, the long list, and now I-35W. Each one of them has created a higher bar. We've raised our game in every single one of these incidences.

And being a fan of DOTs, being a fan of these people who dedicate their lives to bridges, I have to say, I don't think it's a dire situation. I think it's actually important situation. It's not a crisis, but it's - there could be nothing more important than keeping these vital, symbolic structures robust and doing the maintenance.

FLATOW: Well, I...

MCNICHOL: It's not very glamorous, but it's the maintenance.

FLATOW: But if you have - what have you learned if you have fracture-critical bridges that are going to fall down and people are driving over them, and no one is held responsible, criminally or civilly, for - if - whoever gets killed on them, what have we learned?

LEPATNER: Well, let's look at the record. The Silver Bridge that Dan referred to went down on a Christmas holiday night weekday, when that bridge was quite crowded. It was a fracture-critical bridge. An eyebar broke, one little piece broke and the whole bridge went straight down.

At that time, had the Federal Highway Administration, had the National Transportation Safety Board, had the state Departments of Transportation learned properly, they would have added redundancy to the 18,000 existing bridges that were fracture-critical, that had no support. Instead, that same year, that same year, the I-35W Bridge in Minneapolis was built. And no other bridges were obviously seen fit to learn from that tragedy, nor from the Mianus River Bridge in Connecticut that collapsed in 1983, nor from the other fracture-critical bridges that have barely escaped failure because they were closed just before they collapsed. We have not learned, and we have not learned from the I-35W. Because if we had, I wouldn't have to publish that map, SaveOurBridges.com map.

MCNICHOL: Having worked in the federal highway administration...

MILLER: The term fracture-critical has a different meaning slightly than what I'm hearing. A fracture-critical member simply means that there is a particular part of the bridge based on design, usually an older design, where there is no redundancy, but that doesn't indicate that that is going to break. That's not what the term fracture-critical means. It simply means that if that part of the bridge comes under too much tension, the bridge may fail. And what's done in this case is that fracture-critical bridges are given additional inspections and are, you know, put on a basis of greater - relatively speaking - greater attention from the bridge inspection community.

LEPATNER: Bill, what you just said is exactly correct by itself, and there are 18,000 bridges that are fracture-critical in the nation that aren't automatically unsafe. But when that fracture-critical bridge is structurally deficient, which means it's rated poor; which means it has corrosion, fracture cracks, frozen bearings and a whole list that requires it to be posted - posted means you have to close lanes because it no longer can support the intended design loads - now you have created an engineering nightmare, which major bridge engineers who I've spoken to across the country say is not a healthy thing for any bridge. And no one can predict if one of those pieces can break because it's already a failed bridge since it no longer can carry the intended loads.

FLATOW: Do we have - I got a minute left - or two left. Do we have the money, the resources, the political will to fix these bridges?

MCNICHOL: I think we do, Ira. I think that we are a very rich nation, and we have the resources. We're just choosing not to spend them. Politicians do not lead, they follow. And we saw, in the 1920s, private investment in bridges. And I think if there's not a will out there to tax publicly, then we're going to see bridges - which are ideal for public-private partnership - to set up a toll plaza where there's not one or use one that's already existing, and toll these things and toll the interstate highway system.

You know, freeway meant no traffic lights, no grade crossings. It doesn't mean free of charge. And I think we need to start paying for this out-of-pocket because people are not willing to tax the general funds.

FLATOW: Mm-hmm.

LEPATNER: I think Dan is correct. I think we clearly have the money available. People in Washington has signaled that to me. It is a lack of political willpower and political leadership. And understand, if we just address 2,000 of these 8,000 bridges that I'm talking about on that map, then we will spend $60 billion. We will employ one million construction workers, get them off unemployment, get them off food stamps, put them back to work. And the end result of all that process will be fixing our bridges, strengthening our infrastructure, and also, it will become deficit-neutral, as the economists have confirmed. We need to do this and we have to start now.

FLATOW: All right, gentlemen. We have run out of time. I like to thank you all. Barry LePatner is creator of SaveOurBridges.com. If you go to that website, you can see the bridges he's talking about. He's also the author of "Too Big to Fall," and founder of LePatner & Associates, a construction law firm here in New York. Bill Miller is associate professor of civil and environmental engineering at Temple University. Dan McNichol, a journalist and author of "The Roads that Built America," and, "The Big Dig." Thank you all for taking time to be with us today.

LEPATNER: You're very welcome.

MCNICHOL: Thank you, Ira.

MILLER: You're welcome.

FLATOW: I'm Ira Flatow. This is SCIENCE FRIDAY from NPR. Transcript provided by NPR, Copyright NPR.