Sunday, August 05, 2007

The Bridge

I'm sure by now everyone has read or heard or watched the story about the bridge collapse. And I'm certain by now everyone has heard the word "infrastructure" mentioned. I haven't seen anyone politicizing this event yet, but that's mostly because I don't actually spend much time navigating the blogosphere. I'm sure Ann Coulter somehow will blame this on liberals, and I'm also certain someone has already pointed the finger at Bush (or just gave him the finger), but honestly, the roots of this tragedy are deep, and this problem has been growing for a long time. From WFAA:

In 2005, the 40-year-old bridge had been rated as "structurally deficient" and possibly in need of replacement, according to a federal database. The span rated 50 on a scale of 120 for structural stability in that review, White House press secretary Tony Snow said.

The U.S. Department of Transportation's inspector general last year criticized the Federal Highway Administration's oversight of interstate bridges, saying investigators found incorrect or outdated maximum weight limit calculations and weight limit postings in the National Bridge Inventory and in states' bridge databases.


I'm not the first one to ask any of these questions or think of any of this, so it's time to borrow somebody else's work. Fred Clark over at Slacktivist has already put together a nice post on this issue. He directs us to a Star Tribune article about the bridge being "Structurally Deficient":

The deficiency rating is derived from a complex formula that evaluates many factors and condenses them into an overall score. A score of 80 percent or less indicates some rehabilitation may be needed; a 50 percent score or less indicates replacement may be in order.

The I-35W bridge was rated at 50 percent. The rating data was provided to the Star Tribune by the National Institute of Computer Assisted Reporting.

The inventory data also summarize the bridge's status as "structurally deficient." Bridge components are ranked on a scale of 0 to 9, with 0 being "failed" and 9 being "excellent."

In 2005, the bridge's superstructure -- meaning the physical conditions of all structural members -- was rated at 4, records show. The bridge's deck was rated 5, and the substructure, comprised of the piers, abutments, footings and other components, was rated 6.


And yet no imminent danger was predicted for this bridge. Some cosmetic work was being done on it at the time of collapse (from the WFAA article): "This week, road crews had been working on the bridge's joints, guardrails and lights, with lane closures overnight on Tuesday and Wednesday." Nothing substantial. Nothing to bring this bridge's score up at all. Now back to the Star-Tribune article:

The authors said their research helped determine that "fatigue cracking of the deck truss is not likely." They added that the bridge shouldn't have any problems with fatigue cracking "in the foreseeable future" and that there was no need to "prematurely replace this bridge because of fatigue cracking, avoiding the high costs associated with such a large project."

However, the report noted "many poor fatigue details" and said certain members of the main truss should be inspected every two years, as was being done at the time. In addition, the report said, certain sections of the floor trusses had high stress areas that should be inspected every six months.


I think we can give Governor Tim Pawlenty a prize for stupidest quote of the week:

"Gov. Tim Pawlenty said the bridge was inspected by the Minnesota Department of Transportation in 2005 and 2006 and that no structural problems were noted. "There were some minor things that needed attention," he said.


No, you idiot! Those were major things that needed attention! The bridge failed, and when it did it killed people! At least 7 so far, with 8 others missing according to reports I heard this morning. There are two reasons this bridge wasn't maintained. One reason is Pawlenty himself. Of course he's not going to step up and take responsibility, but let's let actions speak for themselves. Dailykos leads us to this article about Pawlenty:

Last May the legislators finally listened, as both the Republican-controlled House and the DFL-majority Senate passed a bill raising the gas tax by a dime, boosting tab fees, and calling for Minnesota voters to decide whether the state constitution should be amended to allow all the proceeds of motor vehicle sales taxes to be dedicated to transportation. The estimated revenue from these measures was between $7.5 and $7.8 billion over the next 10 years, still not nearly enough to remedy problems that figure to cost anywhere from $1 to $1.5 billion annually during the same period. (The discrepancy is a matter of whether you're looking at spreadsheets from the Minnesota Department of Transportation or ones from the Itasca Project).

But it was all a moot exercise anyway. Literally wielding a big red VETO stamp to appease the no-tax crowd that remains hell-bent on a something-for-nothing relationship with government, Gov. Tim Pawlenty deep-sixed the bipartisan transportation bill. "How dumb can they be?" he sneered of the lawmakers who dared approve a tax hike to fix the state's roads.


I'm not saying everyone who's a conservative or everyone who's a Republican is to blame, nor (and especially note this) am I saying let's blame this on the Bush administration. Sure, he hasn't done much for the national infrastructure in his years of tenure, but I guarantee you that a bridge that was built in 1967 didn't suddenly start degrading in 2001. As a matter of fact, according to this article from WFAA, it received its "Structurally Deficient" rating in 1990.

In 1990, the federal government gave the Interstate 35W bridge a rating of "structurally deficient," citing significant corrosion in its bearings. The designation meant the bridge had deteriorated to a point that the load-bearing capacity was below the originally intended maximum. "It didn't mean that the bridge is unsafe," Transportation Secretary Mary Peters said.


But the bridge was unsafe, as is so obvious now. The question at this moment is if the collapse was directly related to or caused by the known issues plaguing the bridge. They're telling us the investigation will take 18 months (conveniently, plenty of time for the public to forget about it) before they know why it collapsed. For some reason, no one was under the impression this bridge was dangerous. Should they have?

So on to the larger issue. Again, with this bridge collapse the word "infrastructure" seems to be on everyone's lips. As so many reports are telling us now, thousands of bridges around the nation have received "Structurally Deficient" ratings on the National Bridge Inventory. Check out the numbers for yourself here. Even in 1992, there were thousands of bridges (federally maintained and non) listed as SD.

The problem isn't merely that our bridges are old. As Stephen Flynn of Popular Mechanics puts it in his editorial:

The fact is that Americans have been squandering the infrastructure legacy bequeathed to us by earlier generations. Like the spoiled offspring of well-off parents, we behave as though we have no idea what is required to sustain the quality of our daily lives. Our electricity comes to us via a decades-old system of power generators, transformers and transmission lines—a system that has utility executives holding their collective breath on every hot day in July and August. We once had a transportation system that was the envy of the world. Now we are better known for our congested highways, second-rate ports, third-rate passenger trains and a primitive air traffic control system. Many of the great public works projects of the 20th century—dams and canal locks, bridges and tunnels, aquifers and aqueducts, and even the Eisenhower interstate highway system—are at or beyond their designed life span.(Emphasis mine)


Lest you think he's over-reacting to an isolated problem, no less a prestigious body than the American Society of Civil Engineers agrees:

Congested highways, overflowing sewers and corroding bridges are constant reminders of the looming crisis that jeopardizes our nation's prosperity and our quality of life. With new grades for the first time since 2001, our nation's infrastructure has shown little to no improvement since receiving a collective D+ in 2001, with some areas sliding toward failing grades.


These are the people who design and build everything, and they give America's infrastructure a D grade. Bridges, dams, roads, railways, sewers, you name it. They know what they're talking about, and if they say America is falling apart, we need to listen. Infrastructure isn't something people want to talk about. Typically only engineers care until something like this happens. It's not a sexy issue for politicians. Until a tragedy occurs, nobody's going to make "safer bridges" part of their campaign platform. And it's been that way for a long time. One of the last great investments the federal government made in our interstate highway system. And when they built it was the last time they put significant money into it. States are typically just as bad. From WFAA again:

Ric Williamson, Texas Transportation Commission chairman, said Texas has skimped for decades on maintenance of about 50,183 bridges – even as soaring population and surging freight traffic combined to demand a nearly impossible number of new roads and bridges.

"You're not going to get anyone in Texas state government – me or anyone else – to admit that we don't have safe bridges," Mr. Williamson said. "But you know what, until the day before that bridge collapsed, you wouldn't have found a soul in Minnesota government who would have said they didn't have safe bridges."


I'm glad he's brave enough to say that. That's exactly the case. Texas is in pretty bad shape too:

Meanwhile, it's no secret that Texas bridges – just like its overtaxed roads – badly need more maintenance. Last year, the Federal Highway Administration flagged 175 bridges and overpasses in Dallas, Collin, Tarrant, Rockwall and Denton counties as "structurally deficient."

Officials had slapped that same label on the failed Minneapolis bridge. More than 2,100 bridges throughout Texas carry the label.

That doesn't mean Texas bridges are ready to fall down, said Randy Cox, TxDOT's top bridge engineer. When an inspection finds serious weaknesses, that bridge is closed or repaired, Mr. Cox said. He said safety remains the state's highest priority.

It's equally clear, however, that Texas isn't spending enough money to maintain its bridges, he said.

"There is a large need, and we work with what we have," Mr. Cox said. "We address the most dire maintenance needs first. But we just are not able to take care of enough bridges per year with the available funds we have."


The problem is very simple. Maintenance and upgrades for roads (and power lines, and water pipes) is necessary on a regular, continuous basis. It requires money. That means taxes. Texas, among other states, dislikes taxes so much that we won't raise them even when we know we need to. We get politicians who lie to us and tell us that everything's fine and that you don't need more taxes to fix things. Well, they're wrong, and we need to start acknowledging that. Otherwise you get situations like Pawlenty telling you that he doesn't need to raise taxes and a bridge that collapses into the river. We're not the only state with a problem though:

In that respect, at least, Texas has plenty of company. Across America, roads, bridges, ports and more are outdated and overtaxed – and everywhere, money to replace or repair them is tight.

"There is no question that we are underinvesting in our infrastructure," said Jack Schenendorf, who spent 25 years as a staffer for the U.S. House's Transportation Committee. "This has been going on for a long, long period of time. And at some point, you pay the price for that."

Mr. Schenendorf, a member of the federal surface transportation policy board, said the stakes are high for Texas and the U.S.

Wednesday's bridge collapse, last month's pipe explosion in Manhattan and other infrastructure failures aren't isolated events, he said.

"It's all related," he said. "Imagine having a house, and you know you have to spend money each year to maintain your roof. You can put that off and put that off – but someday you're going to have a day of reckoning when it collapses. You can't keep getting away with this."


I don't think it's time to start panicking over every old bridge we have in Dallas (and there are a lot of those), but when you read things like this you do start to wonder:

Built in 1935 and used by 35,000 motorists every day, the Corinth Street Viaduct connects Oak Cliff and downtown Dallas. It's much older and carries a worse federal rating than the Interstate 35W bridge that collapsed Wednesday in Minneapolis.

The 3,300-foot-long viaduct received a score of 29 under a 0-100 system that the federal government uses to assess a bridge's structural health and traffic flow, according to state and federal records. The Minneapolis span received a rating of 50, The scores are from 2006.


Well, at least if you fall into the Trinity, there's less danger of drowning than there is of getting sick from whatever's in that water!

4 comments:

adam said...

Great analysis.

adam said...

Bush, of course, has threatened to veto a bridge bill.

http://www.nypost.com/seven/08062007/news/nationalnews/chuck_to_bush__dont_cross_bridge_bill_nationalnews_frankie_edozien_and_eric_lenkowitz__post_wire_services.htm

Jedi4375 said...

I think people are over reacting because they need someone to blame for a tragedy.

This is a tragedy. You don't see mass bridges failing around the country. To the contrary you see them being repaired, replaced, or reengineered.

This is sad but since statistically speaking this is a complete anomoly from the 1,000s of bridges that have similar grades still in use, it is inconsequential.

People want to look for greater things in death than senselessness but sometimes things happen and can not be predicted to a finite degree.

This is a delusion in our own greatness and understanding of science to believe we can conqueor all.

Nat-Wu said...

I completely disagree. It may be folly to think we can avoid every tragedy, but there was no reason this one had to happen. We already know something was structurally wrong with the bridge; the only question that remains is what that flaw was and why it wasn't spotted and repaired. It's foolish to simply say, "These things happen." They don't. This wasn't an earthquake or tornado, things we truly can't control.

And you're completely wrong about the bridges. Did you not read the posting? Repairs and replacements are exactly what's not happening. This bridge collapse could be an anomaly, or it could be the first in an era of old roads and bridges falling into disrepair. We'll have to see.

I don't think it's delusional to think we can keep people from dying preventable deaths.