The Leven Scuba Club describes 5 Mile Reef as one of the few local dives where 30 m visibility can be experienced: a large offshore bommie brimming with pelagics, in 25-50 m. It stresses that it is for experienced divers only and only from a live boat. No further description or position has been published; the name implies a distance of about five nautical miles from its reference point on the coast. It is a site for technical divers. Local knowledge from Leven Scuba Club members is the best way to get the most out of it, and first-time visitors should ideally dive it with someone who knows the site and the tide.

The central north coast between Wynyard and Port Sorell is the home water of the Leven Scuba Club at Ulverstone, whose site list is the main modern source for it, supplemented by the older Marine Life Network guide. The towns of Burnie, Ulverstone and Devonport sit right on the coast, so many sites are within minutes of a ramp or car park, but the reefs are generally low and weedy, visibility is often 5-10 m, and the coast is open to Bass Strait's northerly and westerly weather.

Devonport is the Spirit of Tasmania ferry terminal, which makes these sites the first and last dives for many interstate visitors bringing their own gear. There is no hyperbaric chamber in the north - the nearest is the Royal Hobart Hospital, about 3.5 hours' drive - so dive conservatively, especially on the deeper offshore sites.

An offshore site dived by the Leven Scuba Club from a live boat only; launch at Ulverstone or Devonport. The position is not published - local marks are needed. From the Spirit of Tasmania terminal at Devonport, all central north-coast sites are within about an hour's drive along the Bass Highway.

North-coast ramps are often shallow and weedy at low tide, so time launches for mid to high tide and carry a sounder, radio and tide tables.

The north-west coast faces Bass Strait: north-westerly to north-easterly winds and westerly swell make it rough, while southerly winds blow offshore and give flat seas - light airs and sunny days are relatively common from January to April. Easterly gales are common in the warmer months and close the eastern faces of Rocky Cape and Sisters Island. Tidal streams run along the coast (eastward on the flood), and several boat sites are only comfortable around slack water.

Offshore and exposed; flat calm only.

Live-boat drop onto the top of the bommie at 25 m; plan depth and decompression carefully and ascend on an SMB for pick-up. Turn the dive at half gas (thirds where current or overhead sections are involved), deploy an SMB before surfacing for the live-boat pick-up, and complete a 3-minute safety stop at about 5 m where depth allows.

Top of the bommie at 25 m; deeper sections need decompression training and appropriate gas.

No confirmed commercial dive operator on the north-west coast as of 2026 (older guides mention dive services in Wynyard and Devonport - verify). Sites are dived mainly by the Leven Scuba Club (Ulverstone), other north-west club members and visiting divers with their own boats; Tasmanian Divers (Launceston) runs occasional northern trips.