Waterfall Bay

Waterfall Bay

By ScubaDownUnder Team · 2026-05-13

Waterfall Bay is the first stop south of Eaglehawk Neck for many boat dives on Turrakana / Tasman Peninsula. Michael McFadyen describes a large bay with sheer walls and, after rain, a waterfall, only a few minutes by boat and less than 5 km south of the Pirates Bay wharf. Just around the headland at its southern end is Cathedral Cave, which Discover Tasmania, DAN's Alert Diver and local dive writers all describe as the largest sea cave system in Australia.

Cathedral Cave

McFadyen places Cathedral Caves in a small inlet south of Waterfall Bluff, the headland at the southern end of the bay, at 43°03'49.4"S 147°57'17.3"E (WGS84). Dive boats do not anchor there: they tie up to ropes fixed to the inlet's north and south walls, over about 22 m of water and a bottom of large boulders. The area to the west is called Cathedral Dome.

The system is not one cave but at least a dozen separate, mostly connected caves, tunnels and arches. Cathedral Arch runs right through Waterfall Bluff to the mouth of Waterfall Bay. Another opening leads to Skull Cave, at about 18 m, which has at least six exits. DAN's Brandon Cole swam in through the skull cave's "eyes" at around 15 m and heard waves booming against the cliffs outside every 15 seconds. Beyond Skull Cave lie the Catacombs and passages such as Revelation Bend, which McFadyen calls very dark and quite narrow, and he notes that some of the further caves need very calm water. Indo Pacific Images describes the huge main entrance opening into a wide tunnel with a maximum depth of around 21 m, its walls covered in brightly coloured invertebrates normally found in much deeper water.

Eaglehawk Dive Centre lists Cathedral Cave among its deeper dives for experienced divers, describes sponges, soft corals, sea squirts and anemones on the cave walls, and says these sites reward good buoyancy. Go Dive Tasmania requires Advanced certification (30 m) for its Cathedral Caves trip. These are overhead environments, so stay within your training, carry a torch and agree the route before you go in. McFadyen suggests doing the safety stop on the walls of the inlet, looking at the growth.

The Bay's Reefs

Waterfall Bay also has shallower reef. Go Dive Tasmania runs a "Sea Dragons and Waterfall Bay" trip open to all certification levels (to 18 m). IMAS scientists and Reef Life Survey divers have surveyed the bay's reef at about 4 to 10 m since 1994, and a site at Cathedral at 12 to 16 m. Purple wrasse, banded morwong, toothbrush leatherjackets, rosy wrasse and longfin pike are the fish they count most often, along with blacklip abalone, southern rock lobster, feather stars and red bait crabs. Butterfly perch, longsnout boarfish and weedy seadragons turn up less often.

The bay sits at the northern end of the Waterfall-Fortescue Marine Conservation Area, which covers the water between Waterfall Bay and Fortescue Bay. Parks and Wildlife Service Tasmania says its rocky reefs support banded morwong, longsnout boarfish, bastard trumpeter, real bastard trumpeter, butterfly perch, striped trumpeter, weedy seadragons and a small population of the threatened live-bearing seastar. Fishing is permitted in Tasmania's marine conservation areas.

Conditions

McFadyen dived Cathedral Caves in February in 17°C water with at least 20 m visibility. He gives winter temperatures around Eaglehawk Neck of about 11°C, and Eaglehawk Dive Centre says the winter minimum is 12°C, with a two-piece 7 mm wetsuit comfortable all year. DAN (2015) gives average temperatures of about 13 to 18°C and says the clearest water comes in winter, June to September. Reef Life Survey divers recorded 10 to 20 m visibility at Waterfall Bay and Cathedral. Swell reaches into the caves, so pick a calm day for anything beyond the main entrance.

Site Access and Logistics

Waterfall Bay is a boat dive. Eaglehawk Dive Centre runs two-dive boat trips from the Pirates Bay wharf, and Waterfall Bay lies within its standard range between Cape Surville and Cape Hauy, so no fuel surcharge applies. As at October 2026 a standard two-dive trip costs $160 without gear or $275 with full gear. There is normally no dive guide in the water; a guide is available for a fee by prior arrangement, and the boat needs at least two divers to run. Go Dive Tasmania, whose shop is in Hobart, meets divers at Taranna and launches from Eaglehawk Neck or Port Arthur. DAN noted in 2015 that the nearest hyperbaric chamber is at the Royal Hobart Hospital.

Other boat dives on this coast include Hippolyte Rocks, The Thumbs, Cape Hauy, Sisters Rocks and Fortescue Bay.

Sources

- Michael McFadyen: Cathedral Caves, Eaglehawk Neck - Michael McFadyen: Eaglehawk Neck general information - Eaglehawk Dive Centre: Caves and canyons - Eaglehawk Dive Centre: Our dives - Eaglehawk Dive Centre: Dive services and prices - Eaglehawk Dive Centre: FAQ - Go Dive Tasmania: Boat dives - DAN Alert Diver: Tasmania (Brandon Cole, 2015) - Indo Pacific Images: Diving Tasmania, a guide (indopacificimages.com) - Discover Tasmania: Diving and snorkelling in Tasmania - Parks and Wildlife Service Tasmania: Marine Conservation Areas - Reef Life Survey and IMAS via AODN: survey list, Waterfall Bay and Cathedral - Reef Life Survey and IMAS via AODN: fish counts, Waterfall Bay and Cathedral

Header photo: The cliffs of Waterfall Bay with its waterfall running, seen from the water, by Ed Dunens, CC BY 2.0, via Wikimedia Commons.