Orillia OPP are investigating a serious collision involving a Sea-doo and a vessel that was docked.
The collision happened in Oro-Medonte at around 5:30 yesterday.
The driver of the Sea-doo was taken to a Toronto-area trauma centre with serious, life-threatening injuries by Ornge.
Police then entered into an impaired operation investigation, with the help of the Traffic Incident Management and Enforcement (TIME) team.
A 60-year-old Keswick man, who was a second Sea-doo operator, was also charged with operation while impaired.