Artificial Reefs Reducing Coastal Erosion to Protect Marine Life

The Reef Design Lab has created artificial reefs to mitigate coastal erosion and supply ideal habitat conditions for underwater species. These Erosion Mitigation Units (EMU) were made of concrete mixed with recycled local oyster shells. So far, the company has planted EMUs in Port Phillip Bay and the City of Greater Geelong in Australia.

Besides creating a habitat for various marine species, the artificial reefs also constitute a dynamic snorkeling destination for the local people.

The company used digital molding analysis and traditional casting techniques to produce reusable molds rather than 3D concrete printing. Additionally, they designed these 2-meter-wide units like lotus roots to save material and forged shelters for fish and other marine species such as mussels and oysters. Weighing around 1800 kg, the units are mechanically anchored to the sand and function as a breakwater, thus reducing coastal erosion.

During the six months following the installation, species including shellfish, sponges, and cold-water corals started to colonize the units. An overhang provides a sheltering space for stingrays and pufferfish. Meanwhile, the tunnels and caves in the design protect fish, octopuses, and crustaceans from predators and provide shade for sponges. Furthermore, the small poles covering the units retain water and shelter intertidal species at low tide.