The coastal protection project in the Port of Esbjerg, which is planned to include several hundred specifically designed concrete units, is already showing the first signs of a healthy biological community after just ten weeks.
The first monitoring has been carried out on the six Coastalock units at Nordsøkaj that are part of the ongoing project. The project is planned to expand to several hundred units that will become part of the port’s infrastructure.
After ten weeks, the six units show dense growth of green algae across large parts of the surface, small barnacles in the cavities of the units, and shore crab sheltering within the structure. Compared with ordinary granite rocks in the port, the Coastalock units show a more diverse community settling on the structure after ten weeks, including on surfaces, in cavities, channels and small pools where algae and small organisms can find shelter and food.
After just ten weeks, the Coastalock units are already outperforming mature granite rock armour that has been in place for years. Algal biofilm covers the Coastalock surfaces extensively, barnacle cyprids have recruited into the pool microhabitats, and shore crabs have been found sheltering within the structure, an indicator species signalling the start of a real food web. Different communities are simultaneously establishing across pools, ridges, and flat faces, mirroring natural rocky shore zonation. Surface design, not time, is what makes the difference.
The project is carried out by the Port of Esbjerg and ECOncrete to examine how future port expansion can combine coastal protection, beneficial reuse of dredge material from port development, and biodiversity restoration
“For the Port of Esbjerg, coastal protection is first and foremost part of the necessary development of the port’s infrastructure. It is therefore positive that this project also allows us to examine how new solutions can contribute to better conditions for life below the water surface. The first observations are promising, and we look forward to following the development over the coming years,” says Dennis Jul Pedersen, CEO of the Port of Esbjerg.
ECOncrete is responsible for the biological monitoring of the units.
“It is still early in the process, and the preliminary observations are encouraging: Seeing key indicator species, such as specific snails and beach crabs colonizing the new structures within just a few weeks suggests that the units provide more favorable habitat conditions than the adjacent quarry rocks surfaces”, says Dr. Ido Sella, CEO of ECOncrete.
The Coastalock units are developed with ECOncrete’s technology, where the concrete composition, surface texture and form are designed to promote marine organisms to settle and thrive. In Esbjerg, local dredge material from port deepening is included in the concrete mix, so the project also tests how materials from port operations can be reused in new infrastructure.
The biological development on and around the units is being followed through a multi-year comprehensive monitoring program.
For further project details please reach out for a conversation with our Marine Biologists & Engineers.