Design, Manufacture, Transportation and Installation of “Green Artificial Reefs” in the Galician Estuaries: An Opportunity for a Circular Economy and Sustainable Development

The Galician estuaries are suffering the consequences of pollution and unsustainable fishing patterns. The volume of catches of many species is increasingly reduced, which means serious economic losses for fishing and shellfish activities. The recovery of the marine ecosystems of the estuaries using artificial reefs (ARs) represents a promising opportunity for one of the main socio-economic pillars of Galicia. The application of circular economy principles and sustainable development in the process of manufacturing, transporting and installing ARs is essential to obtain socio-economic benefits with the minimum environmental impact. This paper studies the possibility of manufacturing green artificial reefs (GARs). The incorporation of shell waste from the Galician canning industry and waste materials from the shipbuilding industry allows reducing the use of concrete aggregate. The suitability of the proposed materials is demonstrated by mechanical tests and subsequent statistical analysis. In the evaluation of the sustainability index of different GAR’s, a model based on a multi-criteria decision-making method has been used, considering economic, social and environmental indicators. The global warming potentials and accumulated energy demand associated with a program to recover the marine ecosystems of all the Galician estuaries have also been estimated. The work has considered different manufacturing and transport alternatives and briefly presents several future lines of work. It is important to note that these works have been carried out within the framework of the PROARR agreement financed by the Xunta de Galicia, which aims to develop, manufacture and install artificial reefs that allow the regeneration of Galician ecosystem estuaries.