PAVING THE WAVES

Concrete based coastal and marine infrastructure such as waterfronts, ports, piers, industrial facilities and coastal defense elements dominate coastal zones world-wide. Coastal hardening replaces natural habitats with urban/industrial waterfronts that cannot provide ecosystem services similar to those offered by undisturbed coastlines. As a result, Concrete based coastal and marine infrastructure are often considered as sacrificed zones with no environmental value. Ecological engineering of shorelines schemes is an evolving discipline with the aim of building more inclusive, resilient, and safe coastal and marine structures for people and nature that maximize benefits for ecosystems, society, and economies. To achieve a significant ecological uplift in urban waterfronts, there is a need for large-scale implantation, calling for practical solutions that can be simply and cost-effectively implemented by the conservative construction industry. In the last years, this technology gap was bridged with high-performance bio-enhancing concrete elements that significantly enhance the biodiversity, species richness, and live cover compared to standard “gray” concrete elements, without affecting the operational needs of the infrastructure. World Conference on Floating Solutions 2020 6–8 October 2020 | Rotterdam, NL 2 Bio-enhancing concrete elements that are eco-engineered to support rich sessile communities can serve multiple ecological, environmental, and operational goals. Bio-enhancing concrete elements can also induce the growth of ecosystem engineers that have profound impacts on the way communities develop and, ultimately, on biodiversity. Species like oysters, tubeworms, corals, and the like, which secrete CaCo3 skeletons onto the substrate, are serving multiple benefits. This “biological crust” serves as an active carbon sink, as carbon is assimilated into skeletons of these organisms in a process called biocalcification. In addition, this biogenic calcitic crust that develops on eco-engineered/bio-enhanced structures can also serve to protect the concrete structure in a so-called Bioprotection process. Within this context, Eco-engineered bio-enhanced floating elements (docks, breakwaters, homes) and even future floating cities have great potential of application. In an era of accelerated coastal development, we must promote innovative ways for developing more productive urban coastlines: “Living” urban/hard waterfronts that generate thriving habitats, instead of barren concrete seascapes.