A new long-term management plan for Lady Robinsons Beach will see 68 per cent of the foreshore preserved as beach, while the 32 per cent will be fortified with large boulders to stop erosion.
Bayside Council has adopted this course of action after being presented with eight options following an investigation of the 7km long foreshore by coastal experts.
Proposed targeted sandy beach areas include Brighton-Le-Sands to Kyeemagh, Monterey, Ramsgate and Primrose Avenue to Russell Avenue, Dolls Point.
Some of the existing groynes would be expanded or reshaped.
The initial cost is expected to be $14.5 million, with ongoing work over five years to cost an average of $600,000 annually.
Bayside Council engaged Manly Hydraulics Laboratory, a business unit within the Water Division of the NSW Department of Planning and Environment, to undertake a study to assess the current condition of the beach, investigate past restoration works and develop options to restore and maintain the foreshore for the next 50 years
The consultant's report said, over the last 80 years the foreshore had been impacted by natural storms and changes to wave patterns caused by major infrastructure - Sydney Airport, Port Botany and the Kurnell Fuel Depot.
The Option 8 choice involves preserving and maintaining 4.76km (68 per cent) of the more stable foreshore for passive recreation with high amenity values while 2.24km (32 per cent) would be treated with hard engineered rock revetments and rock armour at the unstable areas.
The council said this would maintain a sandy beach via ongoing nourishment, dune restoration and the provision of public access ways through the dunes.
On other sections, hard engineering solutions, such as rock revetment walls, would be constructed to combat severe wave impacts and continual erosion.
"This option will also include upgraded foreshore amenities like observation decks, new pathways, park infrastructure and were possible include devices to be attached to seawalls to foster marine growth and expand existing seagrasses," the council said.
A master plan is now being developed and will be subject to community consultation before being adopted by council in late 2024.
Bayside councillor and Ramsgate Nippers president Andrew Tsounis, who moved for the adoption of Option 8, said the council must start applying for government grants to fund the initial work while having the master plan completed as soon as possible.
Cr Tsounis said, despite a 2019 project, costing $700,000, in which 28,000 cubic metres of sand was dredged from near the Georges River 16ft Sailing Club at Sandringham and pumped to Ramsgate, the beach in the baths was non-existent for large periods of time.
"We watch the tide closely and have become very adaptable in moving events along the beach to where there is more sand," he said.