Bass Strait, VIC
HMAS J4 was scuttled in 1924 inside Swan Bay, the sheltered estuary on the Bellarine Peninsula side of Port Phillip Heads. She lies in 10 to 17 metres of water and is the shallowest of the J-class wrecks, accessible to Intermediate divers in normal conditions. The pressure hull is partly broken but the conning tower and forward section are recognisable. Sheltered surface conditions make this the most weather-tolerant of the J-class dives and a good first introduction to the wreck cluster. Protected under the Historic Shipwrecks Act 1976 - no penetration, no removal.
Underwater visibility at HMAS J4 Submarine shifts with swell, wind and recent rainfall rather than holding to a fixed range. Calm, settled days after a dry spell usually bring the clearest water.
Right now: approximately 7 m, 98% confidence (updated 23:38 AEDT).
View the live forecast and 7-day outlook for HMAS J4 Submarine →
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