The Leeton is a small steel tug, about 45 ft (14 m) long, scuttled as an artificial reef in the main shipping channel roughly 12 km south-south-east of Whyalla. The Marine Life Society records her in 22 m, and notes that her hull is draped with prawn nets, which can be dangerous, and that the site experiences extremely strong tidal movement, so it can only be dived at slack tide. Scuttled vessels in upper Spencer Gulf quickly become fish havens on the flat, sandy seabed, and the Leeton attracts whiting and snapper, with leatherjackets, bullseyes and tommy ruff around the superstructure and crabs beneath.

Sponges and ascidians encrust the hull. The prawn nets are a legacy of the Spencer Gulf prawn fishery, one of the state's most valuable, whose trawlers work the gulf at night; nets snagged on the wreck present a genuine entanglement hazard, and divers should keep a cutting tool handy and stay off the structure. With depth, tide, nets and shipping traffic, this is a dive for experienced, well-equipped divers who can time slack water precisely.

The year of scuttling is not recorded in available sources. The Leeton pairs with Marek's Reef, a shallower junk reef to the north-north-west, for a two-dive trip. The Whyalla Dive Shop can advise on local tide timing, which differs from the Port Adelaide predictions, and may know the current condition of the nets.

Visibility at slack is often surprisingly good for the upper gulf, and on a clear day the small hull is visible from the top of the shot line.

Whyalla is about 390 km (4-4.5 hours) from Adelaide via Port Wakefield, Port Augusta and the Lincoln Highway, or a 45-minute flight. Launch at the Whyalla marina ramp and run about 12 km south-south-east (20-25 minutes) to the published position (WGS84 33° 09.668' S, 137° 38.570' E). The wreck is in the main shipping channel, so fly a dive flag, keep a lookout on the boat and never dive when a ship is approaching.

Slack water only.

Upper Spencer Gulf has no ocean swell; wind and tide control conditions. Strong southerly and south-westerly winds blow straight up the gulf and raise a short, steep chop, and northerlies stir the shallow water along the northern shores. Tides are large for South Australia (over 2 m on springs) and run hard around Point Lowly and in the shipping channels, so boat sites should be dived at slack water – visibility is often excellent (15-20 m+) at slack and murky when the tide runs.

Winter (May-August) brings the calmest mornings and cold water (11-13°C); summer water reaches the mid-20s but afternoon sea breezes are common. The Marine Life Society stresses extremely strong tidal movement at the Leeton – slack-tide dives only.

Descend the shot exactly at slack, circle the small hull at 20-22 m keeping well clear of the draped prawn nets, and ascend the shot before the tide turns. Carry a knife/cutter and an SMB.

Short slack windows – plan precisely, nitrox useful; no penetration given nets.

Whyalla Dive Shop (Why Dive) may run it by arrangement; otherwise experienced locals with boats.