The southern end of Wollongong Harbour will reopen to swimmers next Tuesday following the completion of repairs to the Fishermen's Co-op Building sewerage system.
Wollongong City Council closed the harbour on January 17 after untreated sewage was found leaking from a sandstone wall.
The leak was first reported on January 11 and later traced to land owned by NSW Trade and Investment Crown Lands.
The northern part of the harbour was reopened on January 22, but the southern portion remained closed after tests found high levels of ammonia, faecal coliforms and enterococci in water close to the leak.
Director of coastal infrastructure for Crown Lands Stephen Wills said the leak was now fixed.
"The leak ceased after completion of repairs to sewer lines adjacent to the Fishermen's Co-op building on Monday, which followed work on the sewerage pump station last week," he said.
"No flow has been observed from the wall since Monday and the odour has dissipated.
"Crown Lands is closely monitoring the performance of the sewerage system and has installed an automated early warning system on the pump station."
The decision to reopen the southern end of the harbour was made at a meeting yesterday between Crown Lands, the Environment Protection Authority, Sydney Water, Illawarra Shoalhaven Local Health District and the council.
The EPA has been undertaking regular water quality tests and will make the results available today.