Structurally Deficient Bridges

Friday, August 3rd 2007, 11:07 am

By: News On 6

OKLAHOMA CITY (AP) _ Oklahoma leads the nation in bridges that are structurally deficient, a classification of disrepair held by the bridge that collapsed in Minneapolis, according to Federal Highway Administration data.

In Oklahoma, nearly 27 percent of bridges were cited by the federal government as being structurally deficient, the highest percentage among the states. A total of 6,300 bridges in Oklahoma and 77,000 bridges nationally share this designation.

The bridge that collapsed in Minneapolis Wednesday, killing at least five people, had a two-decade history of worrisome inspection reports.

A bridge is typically judged structurally deficient if heavy trucks are banned from it or there are other weight restrictions, if it needs immediate work to stay open or if it is closed. In any case, such a bridge is considered in need of considerable maintenance, rehabilitation or even replacement.

On Thursday, Oklahoma transportation officials said the state plans to replace or improve more than 800 bridges, including ones on interstates, during the next eight years. They sought to reassure the public that the state's bridges are safe for motorists.

``We feel the bridges in Oklahoma are safe to travel on,'' John Fuller, chief engineer for the Oklahoma Transportation Department said. ``If they ever get to the condition where we know they are not safe to travel on, then we have and we would close them.

``We devote a lot of effort in the state of Oklahoma to stay apprised of the condition of our bridges.''

Federal law requires bridges to be inspected every two years, but Fuller said Oklahoma bridges are inspected between every six months to a year.

Kyran Mish, the director of the Fears Structural Engineering Laboratory at the University of Oklahoma's School of Civil Engineering and Environmental Science, said the state has a relatively high number of bridges.

``Oklahoma has the bridge inventory of a large state and the financial resources of a small one,'' Mish said. ``We've got all these major rivers flowing through the state and a lot of river crossings. It's very expensive to build and maintain the bridges.

``I wouldn't be afraid, but I would be cognizant of the need to maintain our bridges.''

On May 26, 2002, 14 people died after barges pushed by a towboat crashed into the I-40 bridge in the Webbers Falls area of eastern Oklahoma, causing a 500-foot span to collapse into the river. Crews working around the clock were able to repair and reopen the bridge in 65 days, and construction and engineering firms that worked on the project earned numerous state and national awards.

State transportation officials have offered to share information about this rebuilding project with their counterparts in Minnesota.

The cause of the bridge collapse in Minneapolis remains under investigation. About 12 percent of the nation's bridges are classified as structurally deficient.

Federal Highway Administration data indicates that among counties with more than 100 bridges, the problem appears to be most significant in the Midwest.

Of the 10 worst-off counties with significant numbers of bridges, seven are in Oklahoma or Nebraska.

According to 2006 data from the Federal Highway Administration, 20 Oklahoma counties were among 100 counties across the nation with the highest percentage of structurally deficient bridges.

Those Oklahoma counties were:

Alfalfa, 391 bridges with 154 or 39.4 % structurally deficient

Beaver, 222 bridges with 75 or 33.8 % structurally deficient

Creek, 418 bridges with 174 or 41.6 % structurally deficient

Garfield, 581 bridges with 257 or 44.2 % structurally deficient

Garvin, 410 bridges with 156 or 38.0 % structurally deficient

Grant, 516 bridges, with 267, or 51.7 % structurally deficient

Haskell, 153 bridges with 58 or 37.9 % structurally deficient

Kay, 416 bridges with 162 or 38.9 % structurally deficient

Kingfisher, 336 bridges, with 173, or 51.5 % structurally deficient

Lincoln, 505 bridges, with 267 or 52.9 % structurally deficient

Logan, 311 bridges, with 150, or 48.2 % structurally deficient

Okfuskee, 227 bridges with 77 or 33.9 % structurally deficient