Sustainable coastal development: a comparative analysis of environmental impacts between floating platforms and dredging

The rising sea levels and scarcity of available land for construction in rapidly growing coastal cities have led to the necessity of expanding towards water, in a process known as land reclamation. The SEAform project is designed to address these challenges by creating self-sufficient communities integrated with the marine environment, using interconnected modular floating platforms. The aim of this thesis is to assess the environmental impacts of the floating platforms within the marine ecosystems and to demonstrate the sustainability of this solution by comparing it with dredging, the most commonly used technique in land reclamation projects. Through a comprehensive literature review, the thesis examines both documented and anticipated impacts of similar projects. It provides an overview of the interactions between floating platforms and the marine environment – including shading effects and the creation of new habitats underneath the structure – as well as the impacts of dredging, such as turbidity and the physical destruction of habitats, distinguishing between the construction and operational phases. A systematic and non-site-specific comparison is facilitated by developing an impact matrix that assigns scores to evaluate the spatial and temporal extent of each stressor. Furthermore, the thesis identifies potential receptors, including marine mammals, fish and benthic ecosystem, describing their sensitivity towards the stressors. The results of the analysis concludes that floating platforms have a considerably lower environmental impact than dredging, thus validating the sustainability of the SEAform solution. Finally, the thesis offers recommendations and guidelines for the SEAform project, rooted in the evaluated environmental aspects. In conclusion, this thesis offers a comprehensive analysis of the environmental impacts of dredging and floating platforms, the greater sustainability of the floating platform solution, and presents project guidelines to ensure an environmentally conscious urban development in marine ecosystems.