Boondelbah Island offers a genuine mix of dive experiences within a single, well-protected location off Port Stephens: sheer walls riddled with swim-throughs and caves on its more exposed faces, contrasted with a distinctly sheltered area known locally as Safety Bay that lives up to its name as a reliable summer training location. This dual character makes Boondelbah a versatile choice for Nelson Bay operators running mixed-experience groups, since the same trip can offer a more demanding wall-and-cave dive for confident divers alongside a calmer, protected option for those still building experience, without needing to travel to two separate islands. The island's protected status reflects its ecological value as part of the broader network of reserves supporting Port Stephens' marine life, and its swim-throughs and caves provide habitat variety that supports a good range of reef fish and invertebrates beyond the open-wall pelagic activity found at more exposed sites like Little Island.

Depths span a comfortable eight metres in Safety Bay out to a more serious thirty metres on the main walls, giving divers of differing certification levels genuine options within the one location. Boondelbah is a sensible choice for a Port Stephens island trip when conditions or group composition call for flexibility, and it complements the more single-purpose sites — Cabbage Tree Island for straightforward training, Little Island for pelagic exposure — with a bit of everything in one place. Its dual character means it is often the operator's choice when a booking includes both experienced divers wanting a real challenge and less experienced companions wanting an easier option on the same trip.

Boats depart Nelson Bay marina and run out past the harbour heads to the islands scattered along the Port Stephens coast — Cabbage Tree Island, Boondelbah Island, Little Island and Fingal Island are all within roughly 15-30 minutes of Nelson Bay, considerably closer than the longer run out to Broughton Island. Exact site choice on the day depends on wind and swell direction, since the different islands and their different sides offer shelter from different conditions.

The Port Stephens islands sit on the open coast just outside the harbour and are exposed to ocean swell, though generally less so than Broughton Island given their closer, more sheltered position relative to Tomaree Head and the harbour entrance. Operators choose the specific island and side to dive based on the day's wind and swell direction. Visibility is typically 8-20 m and best in settled autumn/winter weather; it drops after rain and in a strong onshore blow.

Descend onto the sheer wall and explore its swim-throughs and caves at 8-30 m, or, for training and less experienced groups, use the sheltered Safety Bay side of the island for a calmer, shallower dive in typical summer conditions.

Let's Go Adventures (Nelson Bay) and Feet First Dive (Nelson Bay) both run regular boat trips to the Port Stephens islands group, weather permitting.