ISSUE: Bridge safety

OUR VIEW: SCDOT must maintain vigilant watch on structures; replacing all impossible

The results make news every year, but it is not until a tragedy the likes of the bridge collapse in Minnesota that people pay much attention.

Motorists drive over bridges day in and day out, assuming for the most part the crossings are structurally sound. History tells us that is not always the case. The Minnesota tragedy is not the first such disaster.

AAA Carolinas annually releases a study of bridges in South Carolina based on its analysis of S.C. Department of Transportation data. The February report in 2007 tagged the Caw Caw Swamp bridge on U.S. 178 among the state's worst bridges.

The bridge, which is scheduled to be replaced within the next five to 10 years, is located about a half-mile north of Orangeburg. It is listed as No. 20 among the state's top 20 substandard bridges.

It is not the only one locally. Up to 14 bridges in Orangeburg County alone are due for work or replacement over the next decade.

Do the ratings mean bridges such as the one at Caw Caw Swamp are destined to fail or should not be used?

The Minnesota disaster prompted SCDOT to explain its ratings of bridges and where the state stands with repairing or replacing deficient structures.



Structurally Deficient:

Secretary of Transportation-nominee H.B. "Buck" Limehouse Jr. stressed the rating does not imply the bridge is unsafe or needs to have the load restricted.



Functionally Obsolete:



Substandard Bridges



Load Restricted:

The agency conducts a regular schedule of inspections on all bridges in the state highway system as required by FHWA. These codes have been in effect since the 1970s. The schedule is:

* All non-load restricted bridges are inspected every two years.

* All load-restricted bridges are inspected every year.

* Bridges with underwater pilings are supposed to be inspected every five years according to FHWA codes. However, SCDOT's policy is to examine bridges of this type every four years.

SCDOT makes more than 6,000 inspections per year of state-owned structures. This number includes those bridges that are monitored more frequently to ensure the safety of the public. Additionally, SCDOT performs approximately 65 underwater inspections per year.

While the bridges in the state may not be in danger of collapse, there are needs as identified by the rating system. The federal standards are not meaningless.

"South Carolina has a critical need for funding in terms of maintaining the bridges and highways in our state, but we are doing everything possible to make sure that all bridges can be used safely,'' Limehouse said.

But consider the financial requirement to replace the current list of Structurally Deficient and Functionally Obsolete bridges is estimated at $2.9 billion.

DOT's vigilance will continue to be needed. In the words of Limehouse in referencing the Minnesota disaster: "Safety is our highest priority, and no one in South Carolina will travel over a bridge this unsafe to use.''

SCDOT engineers have placed 138 bridges in the category of "Load Restricted," meaning vehicles surpassing the maximum weight allowed on one of these bridges are prohibited from using the bridge. SCDOT has declared 10 bridges in the state highway system closed to all traffic. are structures that may be both Structurally Deficient and Functionally Obsolete. However, if that bridge falls into both classifications, only the "Structurally Deficient" criteria is counted. The total of "Substandard Bridges'' in South Carolina stands at 1,809. This number is found by adding the total of "Structurally Deficient" and "Functionally Obsolete" bridges. SCDOT maintains 776 bridges that are classified as Functionally Obsolete, meaning the structure does not meet the FHWA codes for providing a certain level of service. An example is an older bridge that has lanes narrower than today's standards. SCDOT maintains and inspects a total of 8,330 bridges. Of those, 1,033 are Structurally Deficient, which means the condition of the bridge does not meet the standards of the Federal Highway Administration.

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