Windang Island sits at the ocean mouth of Lake Illawarra, a small rocky outcrop joined to the southern end of Windang Beach by a shifting sand spit. It is not a destination dive and has little published documentation, but it is used by local divers and spearfishers when they want a quick shore dive close to home, and it is included here for completeness of the Illawarra coastline.

The reef on the ocean side is a mixture of boulders, low ledges and gutters carpeted in kelp, sloping from the platform at 2–3 m to sand at around 10–12 m. It is typical Illawarra temperate reef: blue groper, luderick and bream feeding in the wash, leatherjackets and wrasse among the kelp, cuttlefish in the cooler months and Port Jackson sharks resting on the sand in late winter. Octopus and rock lobster hide in the cracks, and the sand edge is worth checking for rays and flathead.

The defining feature is the lake entrance. On the ebb, water pours out of Lake Illawarra through the channel beside the island, carrying sediment and nutrients; visibility can drop to a couple of metres and current near the channel is strong enough to carry a diver seaward. For that reason the island should be dived on the top of the tide, in calm seas and after a dry spell. Under those conditions it is a pleasant, uncrowded shallow dive for experienced shore divers. Newer divers are better served by the protected sites at Bass Point, 10 minutes further south, which offer similar habitat with easier entries and far more reliable conditions.

Drive to Windang (15 minutes south of Wollongong via the Princes Motorway/Lake Illawarra) and park at the Windang Beach / Lake Illawarra entrance car park off Fern Street. At low tide it is possible to walk across the sand to Windang Island and enter from the rock platform on the ocean side; check the tide carefully because the lake entrance channel runs beside the spit. Boat divers can launch at Port Kembla and run about 7 km south, or launch inside the lake (shallow, tidal bar – not recommended for most boats).

Windang Island faces the open sea and is exposed to swell from the north-east through south-east; it needs a swell under about 1 m. The Lake Illawarra entrance produces strong tidal currents on the run-out, and outgoing water after rain is brown and silty, so dive on or near the top of the tide and not after heavy rainfall. Northerly winds create chop; westerlies in winter give the best conditions.

Enter from the ocean side of the island on a rising tide, follow the kelp-lined gutters and boulder reef around the eastern face at 5–10 m and return before the tide turns. Stay well away from the lake entrance channel.

No regular operator. Windang Dive and Spearfishing (Windang) is the local shop and source of local knowledge; mostly visited by local divers, spearfishers and club members.