The man's friend called police early Thursday after he saw the victim lose his footing, slip down a hill and fall into the river. Detective Brian Miller said the friend tried to rescue the man, but he was unable to find the victim in the dark.
A police officer went into the water and located the man, who was unresponsive. Miller said the man was in the water for 5-10 minutes.
The man was taken to a local hospital. He later died during a transfer to Grand Rapids.
The victim's friend told police the pair had been drinking before the accident.
Miller said police believe the victim was homeless.