Friends of a 19-year-old who drowned after climbing onto a crane in Sydney Harbour have held a vigil at East Balmain in Sydney.

The man's body was recovered from the water nearly four hours after he fell or jumped from a crane on a construction barge early on Thursday morning.

Marcus Atallah was among friends who gathered at the shore after the teenager's body was recovered.

"[He was a] top bloke, probably enjoyed himself the most out of anyone I know and that's the way we want people to know him," Mr Atallah said.

"I think he would want us to be all together, we're obviously distraught but we'll do the best we can to honour him and do the best by him that we can."

Officers from Marine Area Command pulled the body from the water near a barge shortly before 9:00am.

It's believed the 19-year-old man climbed to the top of this crane on a construction barge, before falling and drowning. ( ABC News )

Police said the man and his friend, both locals, swam out to the construction barge about 5:00am before climbing onto the crane.

They said the teenager found dead had climbed to the crane's highest point.

It was not known whether he jumped or fell, but police were told the friend heard a splash after the 19-year-old fell from a height of about 30 metres.

The man's friend then attempted to search for him in the water for about 10 minutes before alerting neighbours.

Police said alcohol was a factor in the incident.

"This is just a case where it appears that skylarking with some alcohol involved has led to the tragic death of a 19-year-old male which, in this case, could've been absolutely avoided," Acting Inspector Alex Barrell said.

The wharf is currently undergoing refurbishments and is closed to the public.