A project is under way at Kurnell to restore natural habitat for fish, rock lobsters and abalone, which was destroyed by raw sewage being pumped into the ocean along Sydney's coastline over many decades.
Underwater forests of a seaweed variety called crayweed were wiped out by the pollution, which continued from the Cronulla sewage plant outfall at Potter Point until 2003 when tertiary treatment was introduced.
Last week, a team of divers attached reproductive crayweed plants to rock shelves in two to five metres of water off Inscription Point, adjoining Captain Cook's Landing Place.
It is expected the implants will reproduce and spread, transforming a barren underwater desert into forests of crayweed that will attract certain species of fish, rock lobsters (crayfish) and abalone back to the area.
The project, covering the entire Sydney coastline, is being undertaken by the Sydney Institute of Marine Science (SIMS), with scientists from The University of Sydney, UNSW and NSW Department of Primary Industries (DPI).
It is underpinned by financial support from the Breen Group, which conducted sandmining on the Kurnell Peninsula and now operates a landfill and resource recovery centre.
SIMS is a partnership between The University of Sydney, the University of NSW, Macquarie University and the University of Technology, Sydney in collaboration with state and federal government departments, the Australian Museum and the University of Wollongong.
Dr Ziggy Marzinelli, from The University of Sydney, who is leading the research component, said the project was a committed team effort, which had delivered major environmental benefits to other coastal areas of Sydney and was expected to be just as successful at Kurnell.
"We are seeing crayweed growing up to 500 metres on either side from where it is planted - about one kilometre in total," he said.
Dr Marzinelli said the Kurnell site was prepared a year ago through the removal and relocation of hundreds of sea urchins, which feed on crayweed and other seaweeds.
Breen Group director Tom Breen said, when the proposal was put to him, he "quickly realised the environmental and local significance of the project and wholeheartedly supported it financially".
"I felt it was a most apt project to support, particularly culminating in the Captain Cook 250th anniversary year and with some of this submarine reafforestation being undertaken at Cook's landing place."