The man, who was in his mid-50s, was said to have fallen from a small transport boat on Saturday night close to Royal Clarence Marina in Gosport.
He was washed away 300 meters because of the harsh weather.
In the vicinity of Millennium Bridge, a woman walking her dog Poppy reported that the cockapoo “suddenly started barking; when she stopped, I could hear someone crying for help so I called the coastguard.”
The man was put onto a rescue boat and given hypothermia treatment after being discovered clinging to a pole in the chilly water.
He was quite fortunate. He was really lucky to survive after spending 30 minutes in the water in a storm force gale at this time of year with the sea temperature what it is, according to James Baggott of the Gosport and Fareham Inshore Lifeboat Service (GAFIRS).
“If the dog walker hadn’t sounded the alert, the circumstances could have been quite different,” the dog walker said. “He was washed away from the tender and left clinging to the pile.”
As soon as they arrived home, Poppy’s owner “spoiled her with treats.”
How terrified he must have been, and how lucky we were to be there at that moment, the woman remarked.