The body of a young man was recovered from Ogden Reservoir in Barley yesterday (Sunday).
Emergency services were called to the scene at 5pm after reports a man, believed to be in his twenties, had got into difficulties in the water.
A huge search operation was launched and at 9pm a body was recovered.
Police are not treating the death as suspicious and a file is due to be passed to the coroner.
A spokesman for Lancashire Police said: "We were called at around 5pm yesterday (Sunday) to Ogden Reservoir in Barley to reports a man had got into difficulties in the water.
"Emergency services attended the scene and a search was launched.
"Sadly, at around 9pm the body of a man, thought to be aged in his 20s, was located in the water.
"At this point his death is not being treated as suspicious and a file will be passed to the coroner in due course."