Bockarie Sonnah, 14, got into difficulty while at Torduff Reservoir in Bonaly Country Park on the outskirts of Edinburgh on Monday night. He was just 20ft from safety, said witnesses.
Bockarie had been playing in the water, and he and a friend were said to have jumped from a 10ft water tower. Shortly afterwards he was seen waving for help before disappearing.
Despite efforts to reach him, he did not surface and emergency services later found his body.
Last night, Chris McArthur, coach of Redhall Star football team, for whom Bockarie had played since he was eight, spoke of a “happy kid”.
Mr McArthur told The Scotsman that players at the club, many of whom left tributes at the scene yesterday, including flowers and a Hearts FC flag, were “devastated”.
Bockarie, from Musselburgh, East Lothian, was described as a popular pupil at Firrhill High School. He was the son of a former 3 Rifles soldier.
Mr McArthur said: “Bockarie was a great guy to be around and was a joy to coach … Our thoughts are with his family.”
Friends also posted tributes on social-media sites.
Cameron Gardner said: “Such a great guy! RIP mladdie!! Xx”
Gary Anderson said: “Crackin lad. Cheeky big smile will be sorely missed.”
James Cunningham was one of a group who heard screams as they arrived at the reservoir.
Yesterday he said: “There were three or four people at the water’s edge and we thought they were kidding, having a laugh.”
He said Bockarie was 20ft to 25ft out and waving his arms.
Mr Cunningham said he grabbed a rope from his van to secure himself and his friends as they entered the water. But the boy had disappeared.
He said: “The water was really cold and we could not see anything under the water … There was no sign of the boy.”
Bockarie previously lived in the Longstone area of west Edinburgh until his father Jusu left the army last year.
Workmen from Scottish Water, which owns the non-operational reservoir, were also on site, fixing a new lock to a gate which leads to a concrete walkway and water tower which juts into the reservoir. Bockarie and his friends were jumping from this jetty, witnesses said.
Angling group Clubbiedean Fishery last night said both their members and police officers had spoken in the past to children about the dangers of swimming in the reservoir.
In a bid to warn others against swimming at the site, they posted on their Facebook page: “Please share this as a warning to others and pass on to anyone you know who either swims in the reservoirs or who has kids who are naturally drawn to this activity.”
Scottish Water said there are numerous signs at the reservoir site warn against swimming.
Police Scotland’s Marine Unit recovered the teenager’s body at around 10pm on Monday. Inspector Liz Duthie said: “This tragic incident demonstrates that all bodies of water can present a number of hazards.”