Dee Why Wide

Dee Why Wide Dive Site Guide — Northern Sydney

By ScubaDownUnder Team · 2025-07-11

Three kilometres east of Dee Why headland, the sand bottom rises sharply into a reef structure that breaks 30 metres up to 18 — a deep ridge of sandstone and weed-covered pinnacles that has, for decades, been one of the most consistent grey nurse shark sites on Sydney's Northern Beaches. Dee Why Wide is not the most famous Sydney shark dive — Magic Point further south draws more press — but for divers based north of the harbour, this is the offshore dive that justifies the boat fare. The combination of depth, structure and a winter aggregation gives the site a character that the shallower beaches around Long Reef cannot match.

The site sits on the broad sandstone shelf that defines the seabed off Sydney's Northern Beaches, in the same general reef system that includes Long Reef Wide and South Long Reef. Dee Why Wide is the sharper, more structural piece of this country — a series of pinnacles and ledges rising from a sand floor that drops away again to thirty-five metres on the eastern side. The site has been worked by Northern Beaches dive boats since the 1980s and remains relatively quiet by Sydney standards, partly because the depth puts it above the Open Water diver pool and partly because the site only fires on the right swell and visibility window.

The dive profile follows the reef structure. A back-roll lands divers on the top of the main pinnacle in 18 to 20 metres; the route runs along the eastern edge of the reef where the wall drops to 28 to 30 metres, around the southern shoulder where the sand sweeps in, and back up along the western face where the kelp grows densely on the upper ledges. Bottom time is short at this depth — twenty minutes is a good working window in air, longer on Nitrox. Navigation is straightforward as long as the reef is followed; once a diver leaves the structure for open sand, the dive is effectively over.

The grey nurse sharks are the headline. The aggregation peaks from June to September when ten to twenty sharks may be holding off the eastern edge of the reef in 22 to 28 metres, hovering with the slow, deliberate motion the species is known for. Outside the peak season the sharks are still resident in smaller numbers — a typical summer dive turns up two or three. Beyond the sharks the reef holds the full Sydney offshore cast: large kingfish working the blue, eastern blue groper patrolling the ledges (males in their cobalt phase, often a metre in length), red and grey morwong in schools along the sand-edge, the occasional bull ray cruising past, and wobbegong sharks tucked into the lower overhangs year-round. Below 25 metres the soft coral growth on the deeper ledges turns the wide-angle work colour-rich.

Conditions at Dee Why Wide are dictated by swell direction and the strength of the East Australian Current. Visibility typically runs 12 to 25 metres, with the better days falling in the cooler months when the EAC is weaker and the silt load is lower. Water temperature ranges from around 16°C in late winter to 22°C in February and March, with a 7mm wetsuit the sensible default given the depth and bottom time. Current along the reef can run strong — half a knot to a knot is common when the EAC is on — and operators choose drift versus shotline based on the day's conditions. The site shuts down on big easterly swells, which break the surface chop and lift the silt off the sand floor.

For experienced Sydney divers, the secondary attraction at Dee Why Wide is the macro work on the deeper ledges. The cooler water and depth mean the soft coral and sponge growth is denser and more colourful than the shallower Northern Beaches sites — the larger Sydney syngnathid species turn up here, as do the unusually large nudibranchs that the deeper ledges grow. Underwater photographers wanting both wide-angle (sharks, kingfish, blue groper) and macro on the same dive find the site delivers both — rare for a deep Sydney offshore reef.

Dee Why Wide is the offshore reef Northern Beaches divers send their visitors to when the swell is right. It will not be the prettiest Sydney site, and it does not advertise itself — but for a depth-and-structure dive with a reliable winter shark aggregation and the room to do macro on the deeper ledges, it is one of the most rewarding offshore reefs north of the harbour.

## Site Access and Logistics

Dee Why Wide is a boat-access-only site approximately 3 kilometres east of Dee Why headland on Sydney's Northern Beaches. Most charters run from the Brookvale or Manly area — typical run time is 20 to 30 minutes from Manly Cove or the Long Reef boat ramp depending on the charter base.

Entry is a back-roll from the charter boat onto a shotline tied to the main pinnacle, or a live drift drop on a slack-current day. Exit is the same line or a free ascent under SMB. Skill prerequisites are real: an Advanced Open Water certification with deep diving experience, comfortable buoyancy at 25 metres, and a working understanding of bottom-time management at depth. Nitrox is strongly recommended and most operators offer it.

Local operators: [Pro Dive Brookvale](https://www.prodive.com.au) runs scheduled trips to Dee Why Wide and the surrounding Northern Beaches reefs. [Dive Centre Manly](https://www.divesydney.com.au) also runs offshore trips covering this site, particularly during the cooler-month grey nurse season.

## Sources

- NSW Department of Primary Industries — Grey nurse shark protected sites: [https://www.dpi.nsw.gov.au](https://www.dpi.nsw.gov.au) - Pro Dive Brookvale: [https://www.prodive.com.au](https://www.prodive.com.au) - Dive Centre Manly: [https://www.divesydney.com.au](https://www.divesydney.com.au) - Michael McFadyen's Scuba Diving — Northern Beaches reefs: [http://www.michaelmcfadyenscuba.info](http://www.michaelmcfadyenscuba.info) - Australian Marine Conservation Society — Grey nurse shark recovery