4 MPH crash causes $1.18 million in damage

On March 19, 2021, about 1138 local time, the towing vessel Kevin Michael was transiting downriver on the Mississippi River with a crew of nine, pushing a 15-barge tow, when the tow struck the bull nose of the upstream main lock chamber guide wall at the Melvin Price Locks and Dam in Alton, Illinois, resulting in the tow breaking apart and damaging the dam gates. No pollution or injuries were reported. Total damages to the barges and dam gates were estimated to be $1,172,227.
The Kevin Michael departed Hennepin, Illinois, on March 17, 2021, and headed down river on the Illinois and Mississippi Rivers for St. Louis, Missouri. During the casualty transit, the Kevin Michael had a crew of nine. The captain was in charge of the vessel and shared helm duties with the pilot. The captain and pilot stood 6-hours-on/6-off watch cycles. The 15 hopper barges (nine loaded with corn or grain and six empty) were arranged in three strings across and five deep. All six empty barges were at the front of the tow. Each barge was either 195' or 200' long and 35 feet wide. The entire tow - vessel and barges - was 1,175' long and 105' wide.
The transit was uneventful, and, on the morning of March 19, the tow neared the Melvin Price Locks and Dam. At the time of the casualty, the river gage at the dam measured 22.8 feet and was rising, and all nine dam gates were raised above the water between 5 and 8 feet.
Up until 1129, the electronic chart system (ECS) lateral slide indicator for the vessel, which showed the speed of sideways movement perpendicular to the course over ground, was near zero. At 1130, the tow was about 300 feet to the right of the sailing line, aligned with the auxiliary lock chamber upstream guide wall. The upstream guide walls were separated by 400 feet. Between 1130 and the time of the contact 8 minutes later, the lateral slide indicator showed the bow and stern moving to starboard (toward the center of the river) with a few short movements to port. The pilot told investigators that when the head of the tow was about 1,000 feet from the bull nose of the main lock chamber guide wall (between 1135 and 1136 based on ECS data), he became concerned with the approach into the lock chamber because the outdraft "really got strong," and the wind was pushing the tow sideways across the river more than he anticipated. The pilot radioed his concern to the two crew members at the head of the tow who were providing him with distances to the guide wall.
At 1138, the empty outboard barge in the second row on the starboard side string contacted the guide wall bull nose, causing the tow to break apart. Following the barge breakaway, the lock was closed to traffic. Nearby towing vessels rounded up the barges. The lock reopened the next day, March 20, at 1950. The lock closure delayed seven southbound and three northbound tows.
Though the outdraft and wind conditions increased the difficulty for landing the tow on the main guide wall, the pilot anticipated the conditions and expected to enter the lock's forebay successfully. As the pilot of the Kevin Michael passed through the Clark Bridge and prepared to enter the lock 1.3 miles ahead, he was aware of the increased outdraft in the approach because he was familiar with the transit and knew the dam gates were fully open. He was also aware of the gusting wind, which he was monitoring with the vessel's anemometer.
There were no restrictions for operators transiting the locks on the date of the casualty. The Coast Guard was monitoring the water levels and the dangers caused by the currents associated with high water. Based on a safety improvement effort in response to several casualties where vessels contacted the Melvin Price Locks and Dam guide wall, in 2018 the Corps of Engineers, at the request of other towing vessel operators, moved the sailing line-the preferred or recommended route within the reaches of a navigable channel. The sailing line was moved toward the left descending bank of the river to compensate for the outdraft that set tows sideways to their intended course, toward the center of the river, before the approach to the guide wall. Though the pilot was unaware that the Corps of Engineers had addressed the risk from the outdraft by moving the sailing line, he had made many successful transits through the Melvin Price Locks and Dam since 2018. Although his course, which was based on experience and knowledge, was closer to the bank than the original sailing line, it was not as close to the bank as the revised sailing line, which left the Kevin Michael's pilot with less room to compensate for the strong outdraft and high winds as the tow approached the locks.
The NTSB determined that the probable cause of the contact of the Kevin Michael tow with the Melvin Price Locks and Dam guide wall was the Kevin Michael pilot ineffectively compensating for the strong outdraft and wind above the dam while navigating toward the lock during a period of high-flow conditions.