The US NTSB issued an investigation report, concerning the allision of the towing vessel Michael G Morris, pushing 30 loaded grain barges, with the Thebes Railroad Bridge, on the Upper Mississippi River in Thebes, Illinois, on April 2016. The vessel and the bridge sustained no damage, but all barges broke away and 16 of them incurred $850,000 in estimated total damage.
The incident
Mississippi River headed for Cairo, Illinois, when the accident occurred. The 30 loaded grain barges were arranged six across (widthwise side by side) and five deep (lengthwise one after the other). Each barge was 200 feet long and 35 feet wide. The entire tow (vessel and barges) was 1,180 feet long and 210 feet wide.
At 0312, about half an hour before the accident, the Michael G Morris operator (or “pilot” on inland/western river waterways) began to flank the vessel through the 113-degree bend at Allision of Michael G Morris Tow with Thebes Railroad Bridge.
Gray’s Point at mm 46 near Scott City, Missouri.1 At 0332, when the vessel had completed the flank through the turn, it was on a course over ground of 191.7 degrees true and a heading of 199 degrees true at a speed of 8 miles per hour (mph) over ground, 1.7 miles from the bridge.
About 0336, with the vessel proceeding at a speed of 10.7 mph, the pilot, as intended, began to line up the bow of the tow with the left side bridge pier of the 651-foot-wide channel span, which he planned to steer through.
The pilot told investigators that, as he approached the bridge, he tried to come right. However, the head of the tow did not swing right and instead continued to the left. AIS data showed that not only did the heading continue to come left, but so did the course over ground until the time of the allision at 0343.
At that point, the third barge on the port side of the tow struck the left bridge pier. The tow broke apart, with some barges hitting the bridge piers. All 30 barges drifted downstream; 28 of them stranded between mm 44 and 31. Two sank, were removed, and were declared total losses of $350,000 in estimated value. Fourteen other barges sustained hull insets and punctures; some took on water. Individual damage estimates for these 14 barges ranged from $2,500 to $55,000, totaling about $500,000.
Probable Cause The National Transportation Safety Board determines that the probable cause of the allision of the Michael G Morris tow with the Thebes Railroad Bridge was the pilot not correctly accounting for the river current in the bend just above the bridge, resulting in his late and insufficient use of rudder while making the turn. Explore more by reading the full report:
