His body was discovered in the lake at Crookes Valley Park just before midnight on Sunday.
A huge search operation was mounted afer emergency services were called at around 7.30pm to reports that a man had got into difficulty in the water
Police said this afternoon that formal identification has yet to take place but his death is being treated as non-suspicious and will be passed to the coroner.
South Yorkshire Fire and Rescue (SYFR) has issued a statement following the tragic death, saying there are ‘too many risks’ involved with swimming in canals, lakes and rivers unless you are part of an organised swimming group.
More swimmers have been spotted in the water at the park again today, despite the events of last night.
The statement from SYFR reads: “Sadly this has turned out to be another tragic water death and our thoughts are very much with the individual’s family and friends at this time.
"Our message to people across South Yorkshire is simple – please stay out of the water unless you are at a proper swimming pool or part of an organised open water swimming group.
“We know how tempting it is to go for a swim in lakes, canals and reservoirs, especially in hot weather like this, but there are too many risks.
“Open bodies of water are often much colder than they look – this can send your body into shock when you jump in and prevent you being able to swim to safety.
“You also have no idea what is underneath – hidden currents, rocks and rubbish being the main dangers that can cause you serious harm.
“With the summer holidays upon us, we call upon parents to speak to their children about the dangers and not giving into peer pressure.
“We really don’t want to see any more heart-breaking drownings in and around South Yorkshire this summer – each one is one too many.”
The Canal and Rivers Trust has also 'strongly advised' against going into water, as 'there are too many risks that you can't see hidden below the surface'.
The trust said deeper water poses its own serious dangers in rivers and canals, and can be much harder to get out of if you can't put your feet on the ground.
Although the water may seem inviting, it can be much colder than anticipated, particularly in reservoirs and docks where the water is deeper.
Low temperatures can cause blood to rush away from muscles to protect the organs and limbs and muscles may become tired very quickly, which can lead to drowning.
Nationally there have been a number of incidents over the weekend involving bodies of open water, with reports of multiple people across Yorkshire getting into difficulty.
The lake at Crookes Valley Park is a popular spot with open water swimmers and a number of bathers were seen in the water over the weekend, despite warnings that it is unsafe to swim there due to a number of factors including the depth of the lake.