In the Marine Protected Area of the Agathoise coast, France, 32 artificial reefs printed in 3D were immersed at the end of May, in order to replace the old dead body system for delimitating the swimming area. This colossal undertaking is the largest international 3D marine ecology initiative in the world.

The city of Agde (that manages the MPA) was the national winner of a PIA (Programme d’Investissement d’Avenir) for the recovery of biodiversity with its project Récif’lab. This 3D immersion is one of the four operations planned in Récif’lab.

The revolutionary system set up on about 10 kms of the Agathoise coast now consists in a series of 32 artificial reefs “XReef” that will serve both as:

  • solid dead body to hold the surface buoy in place
  • new habitat for marine biodiversity in coastal waters

The innovation also lies in the type of construction that is based on 3D printing, using special concrete as a material. The total weight of each module is approximately 1.4 t.

An engineering school in Marseille contributed to studies in specialised basins to determine the module size best adapted to the hydrodynamic conditions of the coastline in the surf zone of the Agde region.

Pour la fonction renforcement de la biodiversité marine, l’impression en 3D sous forme complexe de « feuilleté », avec des cavités de différentes formes et tailles, a permis de trouver le design le plus approprié au développement et à l’optimisation de la faune et de la flore marine méditerranéenne côtière, notamment pour les nurseries. For the marine biodiversity enhancement function, 3D printing in complex “multi-layer” form, with cavities of different shapes and sizes, has made it possible to find the most appropriate design for the development and optimisation of Mediterranean marine coastal fauna and flora, particularly for nurseries.

“After just a few weeks of installation, the reefs are already showing signs of colonisation by flora and fauna” says Renaud Dupuy de la Grandrive, marine environment director at the City of Agde.

The project also makes it possible to optimises the cost of managing offshore buoyage. Thus the new buoyage will be installed and uninstalled only once a year, since it will be sufficient for a diver to hang the water line from the yellow surface buoy to the artificial reef.

The Recif’lab project also plans (or has already implemented) other innovative actions such as the installation of eco designed micro-reefs for mooring floating piers at the entrance of the port and the design of linear nursery micro-habitats on existing supports, or the immersion of an artificial landscape structure by 3D concrete printing to shift the underwater diving activity from coralligenous marine habitat.

More info on the Facebook page of the Agathoise coast MPA