SWA OWS Series: Mullaloo

Off the soft white sands of Mullaloo, the Indian Ocean settles into crystal-clear turquoise waters. Held at Mullaloo Beach in Western Australia, SWA OWS Series: Mullaloo is an open water swimming race in the Indian Ocean. The shoreline is lined with pale sand that gives way to bright, transparent sea conditions, creating a scenic open arena where swimmers plunge straight through the gentle shore break. Over the sand, competitors spot their turning marks set against the vast blue horizon of the Western Australian coast. Part of the state-wide Open Water Swimming Series organized by Swimming WA, the event takes place in late December, welcoming swimmers during the height of the southern early summer.

The schedule caters to a wide spectrum of endurance levels, offering distances of 500 metres, 1.25 kilometres, 2.5 kilometres, 5 kilometres, 7.5 kilometres, and a full 10-kilometre marathon course. Swimmers take on the circuit in the warm sea, circling bright buoys that track across the turquoise water before returning through the shallows. The race atmosphere is distinctly community-focused and relaxed, carrying the laid-back summer spirit typical of Perth's northern coastal beaches where club swimmers, triathletes, and families gather on the sand.

Mullaloo Beach: the name and the December swim

Mullaloo takes its name from an Aboriginal word believed to mean "place of the rat kangaroo", was first recorded in 1919 as Moolalloo Point, and saw urban development begin in the late 1950s. The Mullaloo round is an all-ages (9+) community swim supported by the City of Joondalup and set for Sunday 27 December 2026 at Mullaloo Beach.

Marmion Marine Park: limestone reefs and marine wildlife

About three kilometres down the coast from the race area lies the Marmion Marine Park, established in 1987 as the very first marine park in Western Australia. Spanning 10,500 hectares of coastal ocean between Trigg Island and Burns Beach, the marine park protects a diverse underwater world. Parallel to the coastline run extensive limestone reefs honeycombed with underwater platforms, ledges, and submerged caves. Just offshore from Hillarys within the marine park sits Little Island, a small, uninhabited limestone and sand sanctuary. The waters surrounding the island feature a designated snorkelling trail, offering visitors a clear window to observe sea turtles, sea lions, dolphins, and seasonal humpback whales.

Centaur Reef and the outcrops of Sunset Coast

Back in 1974, Ocean Reef was defined by rolling sand plains, coastal dunes, and rugged limestone outcrops. About nine kilometres from the Mullaloo race area, the outer formations of Marmion Marine Park hold Centaur Reef, an offshore ledge steeped in local maritime history. It was here, approximately 3.7 kilometres offshore, that the merchant vessel Centaur sank on December 9, 1874, after striking the reef's southern edge. At the southern border of the marine reserve sits Trigg Island, a small rocky aeolianite limestone remnant formed from ancient Pleistocene sand dunes. The rocky formation shifts with the tides, at times becoming physically connected to the sandy beach as coastal drift deposits fresh sand across the gap.

In the 1860s, Watermans Bay served as a crucial watering hole for drovers herding livestock along the Coastal Stock Route between Dongara and Fremantle. Inland, the Star Swamp Bushland Reserve was traditionally used by the Noongar people as a seasonal camping ground with access to fresh water and coastal seafood, before 96 hectares were designated as an A-class reserve in 1987. Today, the bay houses the WA Marine Research Laboratories along the beach off Elvire Street, while an old water tower built at the suburb's highest point in 1936 was converted into a local museum and lookout in 1986.

Mullaloo Beach life and nearby Hillarys Boat Harbour

On the sand at Mullaloo, daily life revolves around the active seafront culture of this northern Perth suburb. The water is patrolled by the Mullaloo Surf Life Saving Club, whose volunteers monitor the beach within 400 metres of their clubhouse every weekend and public holiday from October through April. The club maintains an energetic sporting program, training competitive squads in surf boat rowing, open water swimming, board paddling, and beach sprinting. Their presence provides a reassuring backdrop for long-distance ocean swimmers navigating the course. Construction of Hillarys Boat Harbour began in September 1985, and its boat launching facilities opened in October 1986. The complex includes a calm, sheltered beach tucked safely inside the protective embrace of its outer breakwaters.

Visitors flock to the harbour to explore the Aquarium of Western Australia, which exhibits marine creatures from across the state's 12,000-kilometre coastline, or to board daily ferry services that head across the open sea to Rottnest Island. About seven kilometres inland from Mullaloo Beach sits Lake Joondalup, the largest metropolitan freshwater lake in Perth. During the dry summer months, the water level recedes to expose several small islands and an extensive sandbank. The freshwater basin forms an Important Bird Area, providing critical habitat for thousands of short-billed black cockatoos.