Great Barrier Reef · Australia · Wall · Reef
Hastings Reef – Blue Lagoon
A 20 m wall with a sand patch crowded with sea cucumbers
Area photo: Toby Hudson · CC BY-SA 3.0
Blue Lagoon is a named wall feature on Hastings Reef, one of the outer reefs off Cairns. The wall runs down to 20 metres and stays shallow along its top, with a sandy patch on the site where sea cucumbers lie in numbers. Twenty metres is also the deepest water anywhere on Hastings Reef.
Where it is and how deep
16.5307° S, 146.0023° EPublished position for this site.
The dive
The feature is a wall rather than a bommie field: shallow along the top and dropping to 20 metres, which is the deepest water anywhere on Hastings Reef. That makes it a single-level dive in practice. You take the face down early, work along it, and never have to think hard about no-decompression time on the way back up.
A sandy patch on the site is worth a slow pass, since sea cucumbers lie on it in numbers and the open sand makes a clean break from the coral. From there the return is up onto the shallow top of the reef, where the last part of the dive and the safety stop run in water that sits between 24 and 30°C through the year on Hastings Reef.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Fair | Fair | Fair | Good | Good | Prime | Prime | Prime | Prime | Good | Good | Fair |
Season follows Great Barrier Reef: Dry season (Jun–Nov) brings the clearest water and dwarf minke whales; wet-season runoff and cyclone risk lower visibility and reliability Dec–Mar.
Questions divers ask
How deep is Blue Lagoon at Hastings Reef?+
The wall runs to about 20 metres and is shallow along its top. Twenty metres is also the maximum depth anywhere on Hastings Reef, so the site sits well inside recreational limits.
Sources
- Hastings Reef Blue Lagoon — Scubago
- Hastings Reef dive site — PADI
- Australia - Great Barrier Reef - Cairns — Dive The World
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