Philadelphia Marine Units and the Coast Guard were called to the Delaware River off of Linden and Delaware avenues around 3:30 p.m.
When they arrived, they found a 40-year-old man unconscious in the water after falling off a WaveRunner.
The man was pulled from the water.
Authorities then performed CPR.
He was transported to Aria Health Frankford Campus in extremely critical condition.
Police are investigating what led up to the accident.
