RedactedNarrative: On December 5, 2016, at approximately 1315 a single vessel Swamping/Capsizing occurred in Lake Pontchartrain near the Southern Railroad Bridge. Vessel 1 was a 2005 15' Alweld aluminum flat bottom boat (no MI numbers displayed) that was owned and operated at the time of the incident by subject.  He was the only person on board Vessel 1 at the time of the incident. Prior to the incident, Operator was trolling near the Southern Railroad Bridge under the power of Vessel 1's 40 HP Evinrude tiller steer motor. Vessel 1 was headed north, and Operator was actively fishing.  The weather at the time of the incident was poor, it was raining, winds were strong and seas were heavy, also a strong tide was falling. Vessel 1 took on rain water, and waves over the stern, swamped then capsized. Operator was able to don his adult sized type III PFD before he went overboard, but was not wearing it as required by state law, while Vessel 1 was underway. Operator was treated for mild Hypothermia at Slidell Memorial Hospital than discharged a few hours later. Use of Alcohol is not suspected.