An inquiry by the US National Transportation Safety Board (NTSB) has found that the probable cause of the sinking of three towboats and a deck barge was the deteriorated condition of the barge and the infrequent monitoring of the vessels, which allowed the barge to flood and sink, ultimately pulling down the moored towing vessels.
The July 5th 2019 incident saw three towboats and an unnamed deck barge — all owned by Hex Stone Inc — that sank in the Illinois River at mile 20.7 while moored at the Jersey County Grain Company facility in Hardin, Illinois. No crewmembers were aboard any of the vessels.
About 2,800 gallons of diesel fuel were released into the river, most of which was recovered. Damage to the vessels, deck barge, and facility came to an estimated $920,000.
The four vessels involved were 47ft-long towing vessel Chattie Sue Smith, built in 1963, the 55ft-long Mary-R, built in 1964; 54ft-long Mary Fern, built in 1978; and the 50ft-long Teddi B, built in 1989, which was moored with the other vessels on the day of the accident but did not sink. The towboats, all equipped with twin propellers, were moored with a 50ft by 18ft steel deck barge.
The four vessels and the deck barge were moored on the right descending bank of the Illinois River at mile 20.7. There was no one at the facility or on any of the vessels at the time.
At 06:54 the Hardin Fire Protection District was dispatched to the Jersey County Grain Company following an initial report made by a crewmember aboard a passing towing vessel, who had seen that the vessels were sinking. Employees from Hex Stone arrived on scene before the fire department. The company’s river operations manager notified the US Coast Guard regarding the sinking. They also notified an environmental spill response company concerning diesel fuel in the water.
Subsequent to the initial response and pollution prevention efforts, between July 12th and July 19th a salvage company recovered the three towboats that had sunk, as well as the deck barge. An inspection revealed no reported signs of water ingress from the three towboats. Aboard the barge, however, several small holes were found on the deck, the sides (about 6–12 inches from the bottom), and the bottom plating. An open watertight hatch (manhole) on the deck of the barge, which provided access to the midbody compartment for power cords and discharge hoses, was found during salvage operations. The barge was equipped with two electrically operated submersible bilge pumps powered from shore, one in each of the midbody compartments, that were designed to be activated automatically by float switches. Both pumps were tested after the sinking for proper function: one was found to be inoperable.
NTSB noted that, based on a review of the barge’s condition, the holes had probably been present for a significant amount of time and were the source of the flooding. The side and bottom holes would have allowed water to continuously flood the barge’s compartments, which required the automatic bilge pumps to dewater the spaces at frequent intervals.
The NTSB said that, to protect vessels and the environment, it was good marine practice for owners and operators to conduct regular oversight and maintenance of vessel and barges, even during lay-up periods. Oversight should include periodic testing and maintenance of dewatering equipment.