Subcon, acquired by MMA, is a global provider of artificial reefs. Their engineered concrete reef structures support restoration efforts, protect coastlines, bring value to communities and add ecological function to offshore structures such as wind farms. 

Their Wave Attenuating Fringing reefs are specifically designed to protect coastlines during storm surges. These structures allow sediment to pass through while breaking large waves and providing habitat to marine wildlife. This alternative to seawalls and groins has a much greater ecological function while also allowing natural processes of sediment transport to take place, which typically are disrupted by other coastal protection methods. 

Module example - Bombora module

The Bombora module is a cylindrical shaped artificial reef module which’s complex and unique shape incorporates a nature inclusive design that provides a rich environment for marine wildlife while acting as a breakwater to incoming waves. 

Bombora modules can be fabricated rapidly and serve a 50- year design life. Constructed from Subcon’s ‘Blue-Crete’, sustainable design is factored into every part of their lifecycle, including down to the raw materials used in their manufacturing.  Blue-Crete is designed specifically to extend lifetime of modules while promoting marine growth and minimizing carbon footprint. Their compact size provides easy transport to the reef sites while the design of modules is focused specifically on wave attention and habitat enhancement. 

The material used in artificial reef modules can sometimes have negative environmental Impacts due to PH levels, however Subcon ‘Blue-Crete’ is PH neutral to mimic the PH of seawater, encouraging rapid settlement of benthic organisms and preventing changes to ocean acidity conditions.

Watch a video of one of their projects in Exmouth, AUS:

References

Beck, M.W. and G-M Lange (Editors). “Managing Coasts with Natural Solutions : Guidelines for Measuring and Valuing the Coastal Protection Services of Mangroves and Coral Reefs.” World Bank, https://documents.worldbank.org/en/publication/documents-reports/documentdetail/995341467995379786/managing-coasts-with-natural-solutions-guidelines-for-measuring-and-valuing-the-coastal-protection-services-of-mangroves-and-coral-reefs. 

Bridges, T. S., J. K. King, J. D. Simm, M. W. Beck, G. Collins, Q. Lodder, and R. K. Mohan, eds. 2021. Overview: International Guidelines on Natural and Nature-Based Features for Flood Risk Management. Vicksburg, MS: U.S. Army Engineer Research and Development Center

Bridges, Todd S., et al. “Coastal Natural and Nature-Based Features: International Guidelines for Flood Risk Management.” Frontiers, Frontiers, 2022, https://www.frontiersin.org/articles/10.3389/fbuil.2022.904483/full. 

Justin Geldard , Ryan Lowe , Scott Draper , George Ellwood, Adrienne Wood, Toby Roe and Matthew Allen. “Performance of Engineered Wave Attenuating Reef Structures” University of Western Australia 2022