Heritage-listed Cockatoo Island, west of the harbour bridge, is likely to become the site of a major new commercial marina under well-advanced plans being considered by the Sydney Harbour Federation Trust.

The plans would see storage and mooring facilities developed for 155 boats, including up to eight large boats, and the former historic navy facility known as the Sutherland Dry Dock become a berthing and maritime maintenance centre.

The proposed marina for Cockatoo Island.

The plans are being pitched by the proponent, Escape Boating Pty Ltd – which trades as the Cockatoo Island Marine Centre – as a "project to reintroduce maritime activity to the docks precinct of Cockatoo Island".

Most of the boats would be stored in a dry berthing facility in two tiers of open racks 4.7 metres high along the southern apron of the island.