Engineers have been monitoring the bridge every few hours since April 30th,
when they received word two approach span sections on the McCracken
Side of the bridge had dropped about 2 ft. The Old Ledbetter Bridge
has been closed and awaiting demolition since traffic moved to the New
US 60 Tennessee River Bridge on July 31, 2013.
The
additional 1 inch of movement came after about 1 inch of rain in a 24
hour period. Another inch of rain is possible before precipitation
trails off tonight,
prompting McCracken County Emergency Management Agency officials to
touch base with nearby residents to remind them to be alert for signs of
land moving along the bluff.
McCracken
County Emergency Management Director Jerome Mansfield was returning
from a disaster planning conference in Lexington to continue monitoring
the area.
In
additional to the 1 inch of movement at a monitoring point on the
bridge deck, inspectors said a concrete stairway that they used to
access the lower part
of the bluff on April 30th slid down the bluff with moving soil.
When they first investigated on April 30th, inspectors found a land slip along the bluff below the bridge had moved two of the land-based piers.
Since that initial investigation, inspectors have regularly checked the aging structure for additional signs of movement.
According
to KYTC Spokesman Keith Todd, the Kentucky Transportation Research
Center is sending a seismic sensor that will be attached to the bridge
to alert
inspectors to any substantial shift in the sagging approach spans.
“We
expect to have the sensor on site for installation sometime Thursday.
Nearby resident Bill Schroeder has offered to temporarily supply power
to the sensor
until it can be attached to a more permanent power supply,” Todd said.
While
an earlier assessment indicated a collapse of the approach spans is not
likely to impact the main truss over the river navigation channel, the
continued
movement of the approach prompted engineers to step up a number of
ongoing activities:
- Regular monitoring of the approach spans for additional movement
- Placement of a seismic sensor on the approach spans (Likely Thursday)
- Placement of solar powered navigation lights on the main span and piers in case an approach span collapse cuts power to the bridge
- Continued negotiations with contractors in an effort to expedite demolition of the bridge
- Continued communication with the US Coast Guard about developments at the site
- Continued interaction with McCracken County Emergency Management
At
this time, no evacuation of homes along the bluff has been ordered.
Emergency management personnel have talked to nearby homeowners to
update them on additional
movement of land along the bluff.
While
vehicular traffic was moved off the Old Ledbetter Bridge last July when
the New Ledbetter Bridge opened to traffic, the stability of the bridge
is still
of concern to river traffic.
The
Old Ledbetter Bridge opened to traffic in 1931. It was restricted to a
3-ton load limit in January 2012 while the new bridge was under
construction just
upstream. KYTC officials expedited construction of the new bridge and
it opened to traffic on July 31, 2013, eleven months ahead of schedule.
