Bridge panel gets estimates to tear down, repair span
Published 12:00 am Thursday, September 14, 2000
The commission responsible for the care and upkeep of the U.S. 80 Mississippi River Bridge has received two engineering estimates: one for repairs to the superstructure and one to tear it down.
Repairs to the superstructure of the 70-year-old bridge were forecast to cost $4 million by a Baton Rouge engineering firm. The same firm also provided a $2 million estimate to remove the bridge and supports.
The Vicksburg Bridge Commission requested the estimates from the Baton Rouge engineering firm HNTB in the wake of recommendations from two engineering firms and the U.S. Army Corps of Engineers that the bridge remain closed to vehicular traffic until the problems with a pier and railroad supports are remedied.
Commission Chairman Raymond Ray said the commission is not planning to demolish the bridge right now, but asked for the estimate so they could budget for that contingency.
“Somewhere down the line, we know we’re going to have to tear it down,” he said.
Removing the bridge would leave Vicksburg without a rail crossing. Dozens of trains and cargo routes would have to be shifted to Baton Rouge or Memphis.
The two major problems with the bridge are deterioration to the concrete roadway, which forced its closing in September 1998, and a pier that has been moving about one inch every year.
The majority of the repair estimate from HNTB, $3.5 million, is to mend that support which engineers believe is shifting because of movement along the east bank of the river. The remaining expenses include engineering costs and work to strengthen a railroad support that has sunk nearly 2 feet since the bridge opened in 1930.
One theory why the pier is moving, according to engineers from HNTB, is that the east bank of the river is slowly shifting west. A Corps study of the bank has been commissioned to verify that theory, but will not be completed for at least another six months.
“We don’t know what the exact problem is right now,” Ray said. “That will take some time to determine.”
In 1987, HNTB engineers began monitoring Pier 2 after they noticed movement in the base. Ten years later, repairs had to be made after the pier had moved nearly 6 inches.
Engineers have said the movement in the pier occurs when river levels drop rapidly.
HNTB and Neel-Schaffer Inc. of Jackson have recommended the bridge remain closed until those repairs are made and because of the narrow width of the roadway. The roadway measures 18 feet across, but current highway standards call for a minimum of 24 feet.
Last November, 60 percent of Warren County voters elected to reopen the bridge for traffic, but no repairs have been made since the board of supervisors voted 4 to 1 to reopen the bridge to two-way traffic and to spend whatever amount was needed to make the bridge safe.
The cost of repairing the roadway and opening the bridge has been estimated at $2.8 million over a five-year period, but those estimates were made over four years ago and could be higher now.
Funding for the bridge repairs would come out of bridge commission reserves, now about $5.5 million.
That money has come from Kansas City Southern, which pays per-car tolls for use of the rail half of the bridge, and fees charged for utility lines run along the bridge. The lease with the rail company extending to the year 2927 stipulates that the railroad is charged for each rail car that crosses in an amount sufficient to pay for the maintenance of the bridge.
The bridge has been operated by the commission as a private business since Warren County purchased the privately built bridge in 1947.