As you descend the mooring line, the Bonnie Dundee comes into view as a dark patch on the light sand background.  The mooring line leads to the stern where there is still a reasonable amount of structure projecting from the sand, including the steering column and the top of the rudder and one of the blades of the propeller.  The driveshaft from the engine is burried beneath the sand.

The stern is the largest section of the vessel still intact. Thick algal growth, textured by rust, old barnacles and tubeworms, covers all metallic surfaces. There are a huge number of bigeye aggregating all over the wreck.

Moving forward, between 1 and 1.5 feet of hull remains above the sand, the rest having been buried.  The boiler and engine sit proud of the sandy bottom ringed by just the very top of the hull and the distinct outline of the ship. The smokestack from the boiler is still the tallest point in the vessel.

The Bonnie Dundee had a primary boiler and, slightly further foward, a small donkey boiler. Her engine is a compound twin-cylinder engine.  Next you reach the base of one of the king posts, now long gone.  The bow rests sideways, having broken away from the rest of the ship and has itself become mostly buried.

The Bonnie Dundee is an excellent example of how a steel-hulled vessel survives after being wrecked.  Initially, the area immediately behind the bow weakens causing the bow to separate from the rest of the vessel and usually fall to one side before sinking between halfway and two-thirds into the sand.  The decking and bulkheads largely fall apart, leaving only the thicker skeletal beams.  The rest of the vessel slowly sinks into the sand to roughly the point where it would have floated above the water.

History

The Bonnie Dundee left Sydney at 12:30pm on 10 March 1879 bound for the Manning River under the command of Captain J. Stewart with a crew of 21, including one female steward. There were at least three female passengers.

Shortly after 6pm, the Bonnie Dundee was heading North past Swansea with her running lights lit. Travelling in the opposite direction was the SS Barrabool, a much larger vessel at 68 meters length by 9 meters width and displacing 948 tons.  The Barrabool was travelling from Newcastle to Melbourne under the command of Captain J. Clark. The Barrabool had previously collided with and sunk the SS Queensland off Wilson’s Promontory, Victoria.

At about 7:35pm, the Barrabool spotted the running lights of the Bonnie Dundee approximately 5.5km away. Even though the two ships were in sight for quite some time, at 8pm the Barrabool struck the Bonnie Dundee amidships on the starboard side, holeing her beneath the waterline.  

The Bonnie Dundee sank within four minutes just south of Swansea.

While the vessels were still fused together, around six of the Bonnie Dundee’s crew jumped from the deck of the Bonnie Dundee up to the bow of the Barrabool.  The 16-year-old deckhand also attempted the jump.  He did not make it and fell back on the deck of the Bonnie Dundee.  He became injured and eventually drowned when the Bonnie Dundee went under.

As the two ships pulled apart, once Captain Stewart of the Bonnie Dundee realised the vessel could not be saved, he ordered the remaining lifeboat lowered, at which time the remaining crew other than the Captain, three female passengers, a child and the female steward, jumped into the lifeboat and cut it loose.  The stewardess threw the child into the lifeboat as it drifted away from the side of the Bonnie Dundee.

The Captain handed the four women lifejackets. The Captain would be the only one pulled from the water alive as the four women were sucked under as the Bonnie Dundee sank. Their bodies were not recovered.

The Barrabool would later sink a third ship, the Birksgate, in 1894 and earned the nickname ‘The Great Australian Ram’ and a reputation for steering so badly that other ships got out of her way when she approached.

Reference

Max Gleeson (2004) “Destination Never Reached”.

Entering the water to the north-east of Moon Island you find a low rocky reef interspersed with sandy bottom and kelp beds.  Hunting around in the kelp and over sandy areas near the kelp, you can find common sea dragons.  They’re often mistaken for loose weed but it is much easier to find them once you know what you’re looking for.

Working your way back towards the south-eastern point of Moon Island, there are a lot of swim-throughs, gullies and deep overhands, caves to explore.  These are often populated by giant cuttlefish, wobbygong sharks and Port Jackson sharks.

Circling the island, heading south and west, there are a number of caves to explore at about 12 meters depth.  The caves are typically very deep overhangs stretching beneath the island or running across the island, possibly with an open crack large enough to let in light but not large enough for a diver.

Local marine growth consists of spreading sponge in orange, yellow, purple, pinks and reds, occasional hard coral trees, patches of sea tulips and Gorgonian fans.

Moon Island is surrounded by large numbers of schooling pelagics such as bream, yellowtail kingfish and ludricks, which are attracted to the low rock reef.  Occasionally you will find grey nurse sharks in the area. 

Visibility ranges from 5 to 20 meters.  Water temperature ranges from 16 to 22 degrees.

There is a lot of boat traffic around Moon Island as boats enter and leave Swansea channel and there are a lot of fishing activities around the island.

The Arch

In 20 meters depth on the south-east of Moon Island is a spot known as the arch where large boulders rest on a sandy bottom.  One of the boulders has an archway large enough to fit two divers. 

The arch is lined with creeping sponge growth and attracts a large number of schooling baitfish and pelagics such as yellowtail kingfish and sea pike.  It is common to see giant cuttlefish sheltering within the arch.

Swansea Bridge consists of two bridges, the "New Swansea Bridge" to the east, and the "Old Swansea Bridge" to the west. 

The Old Swansea Bridge was constructed in 1955, and until the late 1980s was the central connection from Sydney to Brisbane, after which the F3 Freeway diverted traffic from the Old Pacific Highway.

The New Swansea Bridge was constructed in the late 1980s. Both bridges were renovated in 2004 causing significant temporary harm to the local sea life. About 1200 tones of rock was added to stabilise the channel bottom.

There are two entry points to dive Swansea Bridge (south side).  The first is the old boat ramp on the western edge of the bridge.  The second is the staircase into the water in front of Swansea RSL Club, to the east of the bridge.

The best time to dive Swansea Bridge is on a slack high tide when the water is clearest.  An enormous volume of water travels through the narrow Swansea channel as Lake Macquarie fills and drains with the tide, so Swansea Bridge is subject to a raging current. 

The slack tide, which may last between 45 to 15 minutes depending on the size of the tide change.  It is vital to turn the dive and head back to shore immediately on sensing the current change, lest you end up kilometres from your entry point.

Be careful to note that the tide times published for Swansea reflect the tide times on the coast.  The tide times at Swansea Bridge will be between 1.5 to 3.5 hours behind the tide at the coast, depending on the size of the tide change. 

The water temperature ranges from 8 to 24 degrees.  Visibility ranges from 5 to 15 meters.