As part of the implementation of the Gold Coast City Council’s Ocean Beaches Strategy, an artificial reef has been created to enhance protection of Palm Beach – and it is now complete!
Located approximately 270 metres offshore from Nineteenth Avenue between the beach and the existing natural reef, the Palm Beach Artificial Reef is 160 metres long and 80 metres wide.
The artificial reef is constructed of large rock boulders and is 1.5 metres below the average water level at its highest point. Significant investigation and design effort has gone into designing the artificial reef, including coastal data analysis, computer modelling and wave tank testing.
Image: Section view of the artificial reef showing rock sizes
Protecting Palm Beach
The reef works by influencing the surrounding waves and currents to help prolong the benefit provided by the sand delivered through phase one, and promote a long term increase in sand along sections of Palm Beach.
Image: Aerial view of the area benefited by the artificial reef
The increase in sand will generally be located just offshore within the surf zone, not always distinctly visible to beach users, but in a position to act as a protective buffer from erosion into the future.
While the primary purpose of the artificial reef is coastal protection, surfing outcomes have been considered during the design of the reef, in line with the City’s Surf Management Plan. Under certain swell conditions there is predicted to be waves breaking on the reef suitable for intermediate and advanced surfers. For surfer safety information, see below.
Reef construction
The artificial reef was constructed using 60,000 tonnes of rock quarried in South East Queensland. The rocks, each weighing up to eight tonnes, were loaded onto barges at the Port of Brisbane before being transported to the site offshore from Palm Beach. Specialist marine equipment then accurately placed the rock to build the artificial reef.
Image: The temporary exclusion zone around the offshore construction site which has now been removed
Construction of the $18.2 million artificial reef took place between April and October 2019, to coincide with when ocean conditions are generally calmer. Marine construction works of this nature are sensitive to wave conditions and can only proceed when safe.
All construction works at Palm Beach were marine-based. To ensure the safety of all beach and ocean users, a temporary exclusion zone was established offshore around the artificial reef construction site.
All watercraft, swimmers and boardriders are now free to enter the area.
Source: Gold Coast City Council
