The Cape Jervis barge is a small wreck with a big story. In early September 1880 the steamer SS Sorata stranded on a rock ledge about a mile south of Cape Jervis, and a major salvage effort followed. Among the vessels brought in was Hopper Barge No. 3, an iron barge 34.8 m long built at Glanville only months earlier, in January 1880, used to carry silt as part of the attempt to refloat the steamer.

On 21 October 1880 the barge sank in heavy weather. The wreck was rediscovered by chance in 1968, when three spearfishers swept around the rocks in deteriorating conditions came upon an old barge. The Marine Life Society of SA has since investigated whether this 'mystery wreck' is Hopper Barge No. 3, and concluded that it very likely is.

The Marine Life Network describes the site as a low reefy bottom in about 6 m with the wreck of an old iron barge used in the rescue of the Sorata – a small but interesting diversion. Expect broken iron plates and frames colonised by algae, sponges and small invertebrates, with reef fish such as old wives, sweep, magpie perch and wrasse sheltering among them. The shallow depth allows plenty of time to examine the remains.

The site suits Open Water divers interested in maritime history, ideally combined with Fisheries Beach or a visit before or after the Kangaroo Island ferry. The two sources place it slightly differently, so confirm the position. As a historic shipwreck, it must not be disturbed.

Drive to Cape Jervis (about 1 hour 45 minutes south of Adelaide). The Marine Life Network places the barge about 800 m south of the jetty, 100 m offshore, east of the boat ramp toward Fishery Beach, while the Marine Life Society's research gives a position about 160 m offshore south of the cape (-35.6245, 138.094). Confirm the mark before diving.

Park near the Cape Jervis boat ramp, and either swim out from the nearest shore point or use a small boat from the ramp.

Cape Jervis sits beside Backstairs Passage, where tidal streams can be strong; dive at slack water. The site is exposed to westerly and south-westerly weather and swell; it is best on calm days with light easterly or northerly winds. Ferry wash and boat traffic near the terminal add surface chop.

Visibility is often good due to oceanic water.

Locate the barge by GPS or transit, descend and circle the wreck at 6 m, then explore the low reef around it. Keep the dive compact and near the surface marker because of boat traffic.

No regular operator; researched and occasionally dived by Marine Life Society of SA members.