Monday, August 06, 2007

International Herald Tribune Editorial - A bridge collapses

International Herald Tribune Editorial - A bridge collapses
Copyright by The International Herald Tribune
Published: August 5, 2007

America's physical foundations seem to be crumbling. Last week, a 40-year-old interstate highway bridge collapsed in Minneapolis, plunging rush-hour traffic into the Mississippi River 60 feet below. Two weeks earlier, an 83-year-old steam pipe under the streets of Manhattan exploded in a volcano-like blast, showering asbestos-laden debris. And two years before that, substandard levees gave way in New Orleans, opening the way for the floodwaters of Hurricane Katrina.

These are some of the most dramatic signs of America's failure to maintain its aging physical structures at a time when demands on roads, transit systems, sewage treatment plants and other vital facilities are rising. In the event of a catastrophic failure, many lives can be lost. But even the slower deterioration undermines the quality of life and retards economic growth.

In the midst of ballooning deficits and a hugely expensive war, most politicians will be tempted by the quick fix. But that is exactly how the country got into this problem.

No one yet knows what caused the Minneapolis bridge to fall apart. Theories include undetected cracks or metal fatigue, vibrations from a resurfacing project on the roadway, or possibly soil erosion around the underwater supports.

The design of the structure was almost certainly an element. The 1,900-foot span lacked much redundancy for its critical supports, which could allow a single failure of a crucial structural part to bring down the whole edifice. The notion that critical parts ought to have backup systems seems so basic to current engineering practice that it is shocking to learn that some 756 bridges of similar design around the country also lack redundancy. They will need to be inspected and monitored with great care.

Unfortunately, the adequacy of current inspections is also in question. It is disturbing that the pipe that burst in Manhattan had just been declared sound by a utility crew, that the levees in New Orleans had been regularly inspected by the Army Corps of Engineers, and that the Minneapolis bridge had been inspected annually.

In these and other failures it will be important to establish whether the inspectors failed to do a diligent job or whether the problem is that inspections are inherently limited.

The larger problem of crumbling roads, bridges and levees and crashing electrical grids can almost always be traced to a lack of investment. When budgets are tight, elected officials find it convenient to cut back on maintenance and leave some future administration to deal with the consequences. When Congress appropriates money for public works, the legislators typically prefer shiny new projects that will enhance their reputations, not mere maintenance on a bridge named after someone else.

Congress is now scrambling to provide extra money to help Minnesota replace its stricken bridge and is planning hearings on broader infrastructure needs. One sensible bill that ought to be quickly passed would set up a commission to assess the state of America's infrastructure, set priorities, and recommend financing approaches.

Another bill is proposing a new national bank to leverage both public and private investment for repair and new construction projects.

The collapse of Minneapolis' Bridge No. 9340 is a reminder that such long-postponed investments can no longer be neglected.


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