Crews pulled a man from the water inside the Edgewater Yacht Club just after 12:30 a.m. Monday after he fell off a docked boat.
According to Cleveland EMS the man slipped, hit his head and fell into the water where he was found by rescue crews.
The man was taken by Cleveland EMS to Lutheran Hospital.
Medics were performing CPR on the man as they rushed him from the scene.
He is in unstable condition.