Port of Esbjerg uses dredged sediment

Port of Esbjerg is reusing dredged clay from its own harbor works in concrete armor units for coastal protection, according to project descriptions published in April by ECOncrete, State of Green and the World Port Sustainability Program. The Danish port is working with ECOncrete on Coastalock units that combine a lower-cement concrete mix with surface features designed to support marine habitat. MaterialDistrict highlighted the project this month as an example of circular coastal infrastructure that pairs sediment reuse with biodiversity measures. The project sits alongside the port’s eastern extension and near the Wadden Sea area, according to the World Port Sustainability Program. ### How is dredged sediment being used at Esbjerg? ECOncrete said on April 12 that clay from dredging at the Port of Esbjerg is being used in the concrete mix for Coastalock armor units. The company said the units are intended for coastal resilience works and for creating habitat for a healthier marine ecosystem. State of Green, which republished details of the project in April, said the dredged clay replaces a significant portion of the cement in the mix. (materialdistrict.com) The World Port Sustainability Program describes the work as a feasibility study on the circular use of port-dredged clays for bio-enhancing ECOncrete Coastalock units. The program said the port is pursuing the project because it needs robust coastal protection for its eastern extension and wants to enhance marine biodiversity near Wadden Sea National Park. (econcretetech.com) ### What are the concrete units supposed to do besides protect the shoreline? ECOncrete said the Coastalock units are designed as next-generation port infrastructure that can build coastal resilience while creating habitat. CORDIS, the European Commission’s research results platform, said ECOncrete’s products use rough, irregular surfaces and openings intended to mimic natural conditions and provide shelter and breeding spaces for marine life. (sustainableworldports.org) MaterialDistrict said the Esbjerg project shows how circular materials and ecological design can work together in port infrastructure. Its article said the port reuses dredged sediment to create concrete elements for coastal protection while also supporting marine biodiversity. ### What is the practical case for reusing dredged material? (econcretetech.com) MaterialDistrict said dredged sediment is often treated as a waste stream even though disposal can be costly and time-consuming. In a separate materials case on dredged-sediment concrete, the publication said using dredged material in concrete can cut emissions compared with conventional concrete, though that older example referred to a different Dutch company and product. (materialdistrict.com) State of Green said replacing part of the cement in the Esbjerg mix lowers the project’s carbon footprint and creates a circular pathway for future port infrastructure. That characterization was attributed to the project participants’ description of the work. ### How much of the project is already in the water? State of Green said in April that the first Coastalock units had already been installed and that hundreds more would follow in the coming months. (materialdistrict.com) Dredging Today, citing the same project, reported on April 15 that the Port of Esbjerg and ECOncrete were integrating port-dredged clay into production of the units for coastal protection and biodiversity enhancement. (stateofgreen.com) The World Port Sustainability Program lists the Esbjerg initiative under 2025 infrastructure projects. That listing indicates the work has moved from feasibility framing into early deployment, though the available public descriptions reviewed here do not give a total project budget or a final completion date. (stateofgreen.com) ### Who is tracking whether the biodiversity claims hold up? State of Green said the biodiversity and ecosystem effects will be tracked through a monitoring program that includes AI-powered underwater cameras from Copenhagen-based Anemo Robotics. ECOncrete and Green Marine Europe also said the Esbjerg pilot is intended to measure whether reused dredged clay and habitat-oriented concrete design can work together in active port infrastructure. (sustainableworldports.org) Anemo Robotics’ role is one of the few named next-step elements in the public material. The project page on the World Port Sustainability Program remains the clearest public listing for the participants and the 2025 study framing, while ECOncrete’s April 12 release and State of Green’s April update provide the latest public detail on installations and monitoring. (econcretetech.com) (stateofgreen.com)