RedactedNarrative: On April 25, 2021 at approx 7:00 pm, a 40' wooden trawler type vessel,", with two persons on board, was east bound in the North Shore Channel in the Lake Ponchartrain Middle Ground area (between the Old Hwy 11 bridge and the I-10 Twin Span) and  collided with the I-10 Twin Span overpass fender system (south side of the channel). The owner and operator of the vessel, was operating the vessel eastbound from Mandeville to Slidell. His wife, was also on board the vessel. The vessel was perpendicular to the bridge upon impact. Operator stated that he believed that his engine was operating at around 1700 RPM's at the time of the collision (approx. 5-6 knots). The vessel approached the I-10 Twin Span to navigate under and through the bridge when the vessel struck the south side piling and fender of the overpass at an angle of almost 90 degrees. The vesel sustained major damage to the bow and quickly took on water, swamped and partially sank.  It is not known why the vessel veered off course and struck the bridge's large concrete bumper system.  After impact, both subjects donned their PFD's and used the vessel's VHF radio to issue a mayday call on channel 16. A vessel in the immediate area responded to the call and both subjects were safely returned to shore. They both refused service from EMS personnel. St. Tammany Sheriff's Office deputies responded to the incident and notified LDWF agents. The operator admitted that he consumed one beer in Mandeville and one beer while traveling from Mandeville toward Slidell within a 4-hour period. Alcohol is not believed to have directly contributed to the incident. Although Operator was not sure why he veered off course, he believes he was not paying attention and became distracted while using his iPad just before the incident. Also, it is believed that Operator did not maintain a proper lookout, and that Operator was in the shower at the time of the incident.