The man, a 28-year-old from Isabella Plains, is recovering in Queanbeyan Hospital.

Queanbeyan Police were called to the Googong Dam foreshore at about 7.30 on Thursday morning.

A car was spotted in the foreshore reserve car park by rangers, who became concerned about the owner's welfare and called police.

Detective Sergeant Michael Handley said more information came to light shortly after police arrived at the scene.

"We were notified by a lady on a canoe that she had found a man in the water some distance between Rabbit Island and the eastern foreshore," Detective Sergeant Handley said.

"It was some several hundred metres off land."

"She towed him over to the eastern foreshore and the rangers were then able to assist with their boat," he said.

Police said the man was in the water for "a considerable time".

He was treated for minor injuries and hypothermia by paramedics.

Police investigations are continuing.

Anyone with information is urged to contact Queanbeyan Police on 6298 0555 or Crime Stoppers on 1800 333 000.