Thirty loaded grain barges being pushed downstream in a strong current by the MV Keith Darling struck a pier of the U.S. 80 bridge head-on at about 6 p.m. Wednesday, scattering barges and sinking at least one.

Nobody was reported injured. Damage to Pier 4 could not be determined, said Herman Smith, bridge superintendent, because a pendulum weight inside the pier that would show any shift could not be read. Smith faulted a three-day emergency operations drill conducted during the first week of the month that simulated a bridge disaster. The pendulum was apparently fouled and had not properly been reset.

Though no assessment of damage could be made, trains resumed crossing at about 11:20. p.m., after Kansas City Southern officials released from liability Warren County, which owns the bridge, and the Vicksburg Bridge Commission, which manages it.

The Interstate 20 bridge immediately south of the U.S. 80 bridge was not struck and remained open.

“We talked to MDOT, and the engineers didn’t find any reason to close the bridge,” said Trooper Wayne Smith of Mississippi Highway Patrol.

Smith said engineers will continue to try to assess Pier 4 for structural damage today. The position of the pendulum, a weight at the end of a long string, is marked inside the pier. It swings after any impact, but if it comes to rest at the marked spot it indicates the pier was not shifted or tilted by the impact. Smith assessed the force of Wednesday’s blow as “about average” for such incidents.

Richard Odom of Red Carpet Security, which monitors the bridge entrance, said the barges jolted security cameras on the bridge, something he said he didn’t think had ever happened before.

“It hit so hard it jarred the Pier 2 camera and turned it 180 degrees,” he said.

Ergon Marine sent boats promptly to round up about 10 barges that broke loose. The others didn’t break away from the pack.

“Thanks to their quick response they were able to contain the barges before they caused more problems,” Warren County Sheriff Martin Pace said.

One of the grain barges upended and floated perpendicular in the water, coming to rest about 500 feet from the Mississippi bank, where its tip could be seen poking out of the water just beyond Rainbow Casino.

Nobody at the AEP MEMCO company, which owns the MV Keith Darling, could be reached.

Tows approaching the bridges from upstream must complete a turn along an almost 90-degree bend in the Mississippi and align themselves for a straight shot between the bridge piers. Faster currents at higher stages make the turn more difficult.

Barge accidentsOct. 3, 2007 — A 42-barge tow breaks up about a mile north of the bridges and several strike the bridge.Feb. 1, 2007 — A fuel barge ignites after hitting a pier, breaks away and careens downriver.2006 — A barge carrying soybean and steel scrapes Pier 3.2005 — In eight days, barges hit the bridges in three accidents