The Kwinana Grain Terminal is an 800 m working jetty where grain ships load at the T-head, and one of Perth's best macro shore dives. About 600 m of the structure is diveable and the main area is around 450 m long. Pylon clusters stand about 10 m apart and the jetty is some 15 m wide, so there is a lot of structure to cover.

For most of its length the jetty stands in 4–7 m over flat sand. The pylons are the reef: each cluster is densely covered in sponges, ascidians, hydroids, mussels, soft corals and anemones, and Howies' description of them as miniature cityscapes fits. Nudibranchs, flatworms, shrimps, crabs and octopus live in this growth, and seahorses and globefish are regular finds. Between the clusters the sand is bare and life thins out.

The character changes near the end. The seabed becomes undulating, with hills and troughs, the pylons get larger and more angular, and the depth drops to 12–15 m in the gloom under the T-head. Schools of old wives, trevally, snapper and bullseyes hang in the shade, and giant trevally sometimes patrol the end.

The site asks for planning. A long swim out and back, a 600 m structure and the temptation to keep going make air management important: use the thirds rule. Divers must stay away from the T-head when ships are berthed or approaching. The car parks have a history of break-ins.

KGT suits Open Water divers who know their air consumption, macro photographers and night divers. Beginners can enjoy the first section near the ladder.

Follow Rockingham Beach Road north from Rockingham (about 5 minutes) or south from Kwinana Beach Road to the CBH terminal. A car park screened by tall grass lies on the left when coming from the Wreck Trail (on the right from Kwinana Beach Road); a less secluded car park south of the terminal adds about 500 m of walking. Walk the sand path to the beach, then surface-swim about 200 m along the north side to the yellow marker buoy and ladder before descending.

Divers wanting the deeper T-head swim a further 100 m or more first. About 45 minutes from the Perth CBD.

Cockburn Sound shelters KGT from ocean swell much like the Wreck Trail, and it remains diveable in moderate conditions up to about 2 m of ocean swell with a 14-second period. Because most of it is shallow, surface wind still matters: moderate northerlies set up a current along the jetty and westerlies push swell and chop in. The summer south-westerly sea breeze arrives around midday, so dive in the morning.

Never dive when a ship is berthed or approaching; propellers and thrusters start without warning.

Descend at the marker buoy and ladder on the north side in 4–6 m. Follow the pylon rows seaward, working each cluster for macro, and turn on thirds of your air; the full jetty is 600 m of diveable structure. Photographers stay in the first 200 m; experienced divers push to the T-head at 12–15 m, where fish schools gather.

Return under or beside the jetty and plan for a long surface swim home.

A staple for Perth dive schools: Perth Scuba, Dolphin Scuba and Bucket List Diver run guided shore dives, courses and night dives here regularly. Many local divers dive it independently.