MCCRACKEN COUNTY, KY (KFVS) - A contractor for the Kentucky Transportation Cabinet (KYTC) is continuing to develop an alternate plan for demolition of the remaining in-water piers at the Old Ledbetter Bridge site.
When the last steel truss section over the Tennessee River main navigation channel was detonated on Oct. 1, damage was caused to the concrete structures.
KYTC says cracks left in the piers raised safety questions about the drilling process.
Mark Hutchins, Project Manager with C.J. Manhan Construction Company, said the piers had suffered horizontal cracking and extreme deflections.
"In our experience, as well as in all that of our specialty (explosives) contractor, we have never witnessed pier deflections of the magnitude indicated …," Hutchins said. "We would not want to attempt to drill the piers to place explosives without providing some external means of ensuring stability. Given their location in the river, it is not clear how to accomplish this."
KYTC engineers and the company are continuing to work on options, but it may be several weeks before a plan is fully developed and approved.
"Removing the river piers in a safe and environmentally sound manner is among several challenges that were a part of the demolition process from the beginning," KYTC District 1 Chief Engineer MikeMcGregor said. "We continue to work with our contractor and the various federal and state agencies to develop a viable plan to remove the piers."
KYTC says the contractor has continued conventional demolition of the approach spans along the Livingston County end of the Old Ledbetter Bridge.
All steel is down and the contractor is digging around and pushing over the land-based piers.
The contractor has steel and concrete to remove from the McCracken County shoreline where the west approach spans collapsed in June due to land movement.
McGregor said the contractor is required to give the U.S. Coast Guard 15 days advance notice before demolition can start on the river-based piers.
He indicated that would also be appropriate notice to the public when a plan is approved and the contractor is ready to proceed.
Working out details and gaining regulatory approval of the plan could take several weeks or more, according to KYTC.