A barge tow that struck a mooring cell on the Ohio River in March 2023 encountered a strong outdraft current above the McAlpine Dam at Louisville, Ky., during high-water conditions, according to a report by the National Transportation Safety Board.

The 103’x34’ Queen City was transiting the Ohio River with 11 barges in tow when the tow struck the Vane Dike at the arrival point for the McAlpine Locks and Dam ion March 28, 2023. The tow broke apart, resulting in an estimated $2 million in damages to the barges and cargo.

NTSB investigators “determined that the barge tow pilot did not effectively compensate for the strong outdraft current,” the agency concluded.

As the Queen City was navigating through the center span of the Clark Memorial Highway Bridge around 2:24 a.m., the pilot attempted to move the tow west to enter the Portland Channel.

 “But the McAlpine Dam’s outdraft current -- current moving across the lock entrance toward the dam -- pulled the vessel away from the channel entrance. Shortly after passing through the bridge, the starboard side of the tow struck the Vane Dike mooring cell,” according to an NTSB narrative.

 At the time of the contact, the height of the water at the McAlpine Locks measured about 17.5 feet and rising, indicating a period of “extreme high water/extreme high flow conditions,” according to the Mississippi and Ohio Valley and Tributaries Waterways Action Plan. It was near the highest levels of the preceding 12 months.

 “When towing vessel operators decide to steer through an area with strong outdrafts, they must steer a course to account for the set from the outdraft,” the report said. “The Queen City pilot intended to steer into the entrance channel to the locks, knowing that an outdraft would set the tow toward the Vane Dike and the dam gates. Although the pilot attempted to steer the tow to the left, he did not anticipate the strength of the outdraft and its effect on the tow.”

“High currents resulting from high water pose unique hazards for vessels transiting inland rivers,” the report concluded. “In addition, near dams, greater dam openings in high-water conditions lead to high flow rates, which can produce outdraft currents near the dam. Mariners should thoroughly assess the potential impact of outdraft currents when entering or exiting locking channels. Vessel horsepower and vessel handling should be carefully considered. Mariners should also consult available resources, such as Waterways Action Plans and company policies, when passage planning.”

One barge was carrying flammable methanol, a hazardous material. Due to the immediate threat to public safety, air and water monitoring began, and the river was closed. A unified command was established that included local, state, and federal agencies, as well as representatives of the vessel owner/operator. The vessel’s owner activated the vessel response plan, and a designated salvor responded on scene, completed water and air monitoring, conducted vessel surveys, developed lightering and salvage plans.

Salvors safely lightered the methanol barge while it was pinned against the dam, and salvaged all damaged barges from the waterway. 

Owned and operated by C&B Marine Equipment, LLC, the Queen City, built in 1974, had two steering and four flanking rudders, and two 1,500-hp diesel engines each driving a propeller. The McAlpine Locks and Dam. The dam’s five upper gates and four lower gates are 22 feet high and 100 feet wide.

The Vane Dike is located in a river bend just off the eastern end of the entrance to Portland Channel leading to the McAlpine Locks. The dike, measuring 200 yards by 10 yards, extends eastward from the end of Shippingport Island, the northern land boundary of the Portland Channel. The mooring cell is at the end of the dike.