MILITARY OCCUPATIONS WITH DROWNING RISK AND EPIDEMIOLOGY

Various military occupations involve significant water exposure and carry a risk of drowning. These include but are not limited to naval operations at sea, military special operations, combat swimmers, divers, and amphibious assault units. Each unit has risk management measures in place to mitigate the risk of drowning events and subsequently provide immediate aid.

Between 2013 and 2017, 359 recreational and line of duty drowning cases were identified amongst active-duty service members. Generally, members of the Marine Corps are at highest risk as well as members working within motor transport occupations. Off duty alcohol related incidents and alcohol use disorder continue to play a significant factor in drowning risk.2,4

Combat related drowning incidents have been associated with a mortality as high as 37.5% and are often related to vehicle roll overs. One 2-year epidemiology study found that combat related drowning represents 3% of all combat deaths.5-6

Man-overboard events aboard naval vessels at sea are uncommon occurrences but are associated with a high mortality when they occur. Between 1970 and 2020 there were 220 man-overboard events on U.S. Naval subsurface and surface vessels involving 352 casualties with an associated 72% mortality.7

Naval vessel collisions at sea impacting the integrity of the ship’s hull can result in highly lethal drowning events. The 2017 USS Fitzgerald and USS John S. McCain collisions with separate large civilian commercial ships both resulted in significant hull breaches below the waterline. In the two events, there were 85 reported casualties from the combined warship crews, 20% (17) died from drowning.

The epidemiology of drowning incidents during amphibious vehicle training is unknown, but they do occur. In 2020 an Amphibious Assault Vehicle (AAV) carrying 15 Marines and 1 Sailor took on water and sunk during a training exercise. Ultimately 8 Marines and 1 Sailor died from drowning. One severely injured Marine required ongoing critical care and respiratory support.8