The Dunsborough Artificial Reef is the sister of the Bunbury reef, built for recreational fishers under the same program. Wikifishingspots and Recfishwest describe the two reefs as installed in Geographe Bay in 2013/14, each made from 30 purpose-built, 10-tonne concrete modules within 5 km of shore and roughly opposite boat ramps. Madmackie gives the Dunsborough reef's centre point as 33 33.962 S, 115 09.980 E in 27 m, 6.2 km north-east of the Old Dunsborough Town ramp and 5.7 km north-north-east of the Quindalup ramp, laid out as six clusters of fish boxes, and describes it as one of the first reefs deployed - a flagship for the program.

The hollow boxes attract pink snapper, dhufish, silver trevally, yellowtail kingfish and samson fish, which is why anglers use it, and they have become encrusted with sponges and weed. For divers, it is a deep, low-relief site that shows how quickly artificial structure becomes habitat. At 27 m, bottom time on air is limited and navigation between clusters needs a compass and good visibility.

It suits Advanced divers with their own boat looking for something different after the HMAS Swan, which lies nearby. The main hazards are fishing gear snagged in the modules and fishing boats overhead, so fly a dive flag and keep a knife or cutter handy. New demersal fishing rules for the West Coast Bioregion from December 2025 may change fishing pressure on the reef.

Geographe Bay faces north, so Cape Naturaliste blocks most of the prevailing south-westerly swell and sea breeze that close the ocean coast; that shelter and the warm Leeuwin Current make the Dunsborough shoreline one of the most reliably diveable stretches of the South West, and winter north-westerly storms are the main thing that shuts it down.

Launch at the Quindalup boat ramp (5.7 km to the reef, north-north-east) or the Old Dunsborough Town ramp (6.2 km north-east) and run out to the centre point. Locate the clusters on the sounder and anchor on sand clear of the modules. Boat ramps along Geographe Bay include Bunbury (Casuarina), Busselton, Port Geographe, Quindalup and Dunsborough; on the Capes coast the Canal Rocks, Gracetown and Hamelin Bay ramps are small and swell-exposed.

Check the forecast, carry a marine radio and log a trip plan with the local Marine Rescue group.

Sheltered from south-westerly swell by Cape Naturaliste; exposed to north-westerly winds and winter storms. Morning easterlies in summer and autumn give the best conditions; the reef is heavily fished on calm weekends. General pattern in Geographe Bay: sheltered from south-westerly swell by Cape Naturaliste; summer mornings are calm before the afternoon sea breeze, while winter north-westerly fronts roll swell and chop into the bay and reduce visibility for several days.

Anchor on sand beside a cluster, descend to 27 m, circuit the boxes looking inside for fish, then ascend the anchor line; bottom time is short on air at this depth. Agree a turn pressure before descending (half gas, or a third where current is likely), carry a DSMB, and make a 3-minute safety stop at 5 m.

No regular dive charter - a recreational fishing reef; private boats only. Nearest dive services: Swan Dive (Busselton/Port Geographe) for fills, hire, nitrox and charters; no dive shop in Margaret River or Augusta.