How Do Structural Safety, Ecological Functions and Social Development Influence Construction of Ecological Seawalls for Coastal Protection and Sustainability?

With rising sea level and climate change, coastal protection against natural hazards such as typhoons and storm surges becomes increasingly important in densely populated areas. Yet, how to integrate necessary engineering structures for coastal protection with development of a healthy socio-ecological system represents a realistic question challenging both the science community and practitioners. This study is motivated to examine the role and influence of diverse dimensions in the construction of seawalls for coastal protection and sustainability. Focusing on a case along the Qiantang River in China, we structured an indicator framework based on technical standards and literature for guiding the design and construction of ecological seawalls. We explored and illustrated the application of a multi-criteria decision making (MCDM) method to analyze proposed indicators as design factors and their influence in practice as reflected by expert evaluation. Our empirical analysis revealed a heterogeneous role and influence of different indicators and their asymmetric interaction in seawall construction aimed to deliver structural safety, ecological functions and social development. This study provides important insights into the design and management of seawalls as an integrated, nature-based solution for coastal protection and sustainability, informing practice improvement and contributing to the literature.