Slight clerical errors mean another month will pass before bridge commissioners sign off on the U.S. 80 bridge’s inspection report.

Despite an overall favorable rating of “good to fair,” bridge officials focused on less favorable “good to poor” ratings of connecting joints along the bridge’s superstructure. Superintendent Herman Smith said the rating indicates some of the 78-year-old bridge’s joints have failed. Also, he said the ratings don’t account for new joints and new concrete on the unused road deck on the west approach, on the Louisiana bank.

Commissioners planned to consult with Baton Rouge-based HNTB, the bridge’s contract architectural services firm and author of the report, on possible changes in advance of a vote.

Warren County owns the bridge, and supervisors appoint the five commissioners to operate the bridge as a nonprofit business. No passenger vehicles have used the bridge in more than 10 years, but it remains the main crossing on the Mississippi River for trains who support maintenance and repairs through tolls.

More movement was detected in the past year in the bridge’s shiftiest support, pier 2, the first large pier from the Mississippi bank.

Inspectors have recorded 9.94 inches of westerly movement since 1997, with .69 of an inch in 2008. Bearings and concrete atop the pier have been replaced twice since then, with a third project in progress since November. 

The report does not specify last spring’s flooding on the river, which left water at levels above the 43-foot flood stage for about six weeks in April and early May. Commissioners said it’s possible next year’s report might reflect more movement in the pier due to gradual drying of the river banks.

Daily rail traffic on the bridge dropped to 13 trains during 2008, the report said. The figure is down from 19 per day in 2007. Payments from Kansas City Southern for November and December totaled $174,240. The bridge’s cash reserves, funded primarily by tolls paid by KCS, stood at $4.6 million as of Dec. 31, off about $800,000 in the past 18 months. Per car traffic in January was reported by the railroad at 20,832, up slightly from December’s 10-year low of 20,055.

Still, HNTB reiterated its stance that truss beams should be evaluated for fatigue every six months, using railway engineering industry standards. Twelve supporting beams were singled out for possible long-term fatigue on the 2008 report.

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Contact Danny Barrett Jr. at dbarrett@vicksburgpost.com.