Petriana

Meet the site

The Petriana holds an unhappy place in Australian history: her loss produced the country's first major oil spill. She was an iron screw steamer of 1,821 tons and 79 m, built by A. Leslie & Co at Newcastle upon Tyne in 1879 as a cargo ship and converted to a tanker in 1891, by 1903 operated by the Asiatic Petroleum Company, the Shell–Royal Dutch joint venture. On 28 November 1903, carrying 1,300 tons of petroleum from Borneo, she was brought in toward the Heads in thick fog by pilot Henry Press and ran onto the reef on the ocean side of Point Nepean – 'aground on Portsea Back Beach at 7 a.m.' Salvage failed, and to lighten her the cargo was pumped into the sea, fouling the peninsula beaches.

The Scuba Doctor listing describes the remains as lying 'in pieces around 200 metres offshore', with 'the bow relatively intact in 3 metres of water' and the rest scattered over the reef to about 6 m; the wreck 'can be heavily sanded over at times' and the site is subject to 'strong cross currents' and surge. What shows above the sand – plating, frames, the bow section – is covered in kelp and coralline algae, with crayfish and abalone in the iron and sweep, wrasse and zebrafish over the reef, and the clear oceanic water of the Nepean back beaches.

It is an ocean-side site on a surf-swept reef with no shore access, dived rarely by club boats on the flattest ebb-tide days, and its interest is historical: a protected historic shipwreck that marks both the hazards of a fog-bound pilotage and the beginning of the oil-spill era in Australia. Sweep Reef and Beacon Rock lie along the same system to the west.

What you might see

Kelp, coralline algae, southern rock lobster, abalone, silver sweep, bluethroat wrasse, zebrafish, magpie morwong, Australian fur seal

Location

About 200 m off Portsea back beach on the ocean side of Point Nepean, at the eastern end of the Sweep Reef system, 709 m south of Nepean Bay Inner West.