When the Gold Coast tourism industry pondered how it could diversify and attract new visitors a unique solution was an innovative piece of underwater public infrastructure.
The Gold Coast Wonder Reef is the world’s first buoyant reef and combines art, science and engineering to create Australia’s newest dive attraction.
The $5 million project, jointly funded by the City of Gold Coast and the Queensland Government, won Project of the Year in the recent IPWEA Excellence Awards.
Since opening in June 2022, Wonder Reef has created new local tourism jobs and injected an estimated $1.6 million into the local economy.
Just a 10 minute boat ride from the Gold Coast’s marine tourism hub, at a depth of 30 metres, the reef is the newest addition to the Gold Coast dive trail. In its first year, the reef attracted over 1100 divers, 33% of them from interstate and overseas.
Gold Coast Mayor Tom Tate said it was an honour for the project to win the IPWEA award in a competitive field which “showcases the best of Australasia’s public works and engineering masterpieces.”
“Not only does our world-first buoyant reef provide divers with a unique option to explore the underwater world, it has already created a vibrant marine sanctuary for almost one hundred different fish, invertebrate and marine plant species, while showcasing the Gold Coast’s thriving biodiversity,” said Tate.
“Divers and marine enthusiasts continue to document new species in the area demonstrating the ecological significance Wonder Reef plays on the Gold Coast.”
In engineering terms, Wonder Reef is unique because almost all artificial reefs for diving are created from scuttling decommissioned vessels or other disused structures.
Project Manager Kim Mayberry said innovative and creative solutions delivered an iconic purpose-built reef that was cost effective and robust, while providing complex marine habitats and an inspiring experience for divers.
The reef comprises nine buoyant sculptural reefs that extend 22 metres above the sea floor. Each of the buoyant reefs is anchored to the seabed by almost one tonne of chain connected to a 72-tonne foundation reef. The kinetic nature of the reef sculptures allows them to gently move with the energy of the ocean, resembling a giant kelp forest.
Adopting proven engineering methodology used in the offshore oil and gas industry, it was the first time engineering of this nature was applied to the tourism industry.
Key design criteria required the reef to be able to withstand cyclonic waves, adopting 200-years ARI conditions – that wave height is 18.5m with a 15.3 seconds period – Hmax.
To ensure stability of the structures in the harsh marine environment and ultimate safety for divers, complex wave and hydrodynamic modelling was undertaken. How the buoyant structures move in dynamic wave conditions and how the corresponding forces interact with the structures and marine communities were investigated.
This technical analysis and detailed design process took 15 months with specialist input from around the world. Every detail was considered, from the ratio of ballast to the buoyancy, tether length and corrosion protection, to ensure the dynamic sculptures could safely withstand cyclonic storm conditions.
Input from the dive industry, marine scientists and researchers was sought to maximise marine benefits, create ideal habitats for a diverse range of species and minimise the risk of environmental and diver safety issues.
The steel structures were fabricated in Maryborough, regional Queensland’s hub for manufacturing. Key fabrication challenges included the sheer size of the structures and the complexity of the conical shapes curving in two different planes.
The fabrication period, which included pressure testing of the buoyant cylindrical tanks, involved more than 2000 person hours over six months.
298 cubic metres of earth-friendly concrete weighing more than 702 tonnes was used to create the reef foundations.
Fourteen trucks moved the massive reef structures from Maryborough to quayside Brisbane for load out. Given the immense weight of the structures at more than 80 tonnes each, Australia’s largest floating crane – the St Vincent – was used to install the reef.
Wonder Reef represents the creation of 32,000 cubic metres of new reef habitat on previously barren seabed. Despite being in its very early days of development, the reef is already flourishing with marine life. Over time, complex marine communities are anticipated to take centre stage, creating a ‘hanging garden’ for divers to swim-through and explore.
Project: City of Gold Coast
Design and Construction: MMA Offshore
Artist: Daniel Templeman
City’s engaged Project Engineer: Stantec
