Site-specific tsunami risk assessment at Port of Cádiz, Spain

Port infrastructure plays a critical role in the functioning of global and regional economies, acting as key nodes in the logistics and supply chains. However, despite their strategic importance, the threat posed by tsunamis continue to be largely overlooked in current port disaster risk planning and management frameworks. This oversight is particularly significant in coastal regions exposed to active tsunami sources, where high-impact and low-probability, events can have catastrophic consequences. Historical events shows that ports are highly vulnerable to tsunamis. For example, the 2011 Tohoku event in Japan affected over 300 commercial ports and almost 1,700 marina facilities, resulting in economic losses of around US$12 billion (Chua et al., 2021; World Bank, 2023). Nevertheless, port management in many cases continues to be based on reactive approaches and simplified hazard analyses that focus mainly on the extent of flooding, without systematically integrating exposure, structural vulnerability and functional impacts.

In this context, the aim of this study is to propose a tailored probabilistic methodological framework for assessing tsunami risk in port environments. This framework is intended to support decision-making and strengthen risk management and preparedness strategies. The methodology enables the consistent identification and quantification of physical damage and expected losses to key port assets and elements of the logistics chain, within ship-to-shore transfers and storage areas. The approach goes beyond conventional hazard analyses, integrating the following: (i) probabilistic numerical modelling of seismotectonic tsunami generation, propagation and flooding (Seismic Probabilistic Tsunami Hazard Assessment - SPTHA); (ii) assessment of the static and dynamic exposure of typical port assets superstructure; (iii) characterization of vulnerability through the fragility functions of port logistics chain assets, and (iv) assessment of damage associated with loss of functionality, economic losses, and human casualties.

The framework's applicability is validated through a study in the Cádiz Port, Spain, which highlights its potential as an operational tool for port disaster managers. Likewise, the work highlights the transfer of knowledge between the scientific community and the port industry, promoting effective collaboration that allows the incorporation of tsunami threats into comprehensive risk planning and management in port facilities. The results will support Spain’s Port Authority, as well as emergency and response systems at the national, regional, and local levels. Internationally, the developed methodology will serve as a practical approach for assessing tsunami risk in ports exposed to this hazard, while also guiding response protocols and evacuation plans. Given its transferability to other regions, it may also serve as an additional instrument for Tsunami Warning and Mitigation Systems worlwide.