A First Step Towards a Semi-Quantitative Framework for Beach Safety Assessment

This study constitutes a first approach to determine a semi-quantitative framework for recreational beach risk assessment based on the interaction among natural hazards, which include: (i) physical (e.g., waves, currents, etc.); (ii) morphological (e.g., wading-zone slope, seabed profile, etc.); (iii) biological processes (e.g., jellyfish, algae, sharks, etc.), the existence of mitigation measures (e.g., presence of lifeguards, etc.), and beach visitors characteristics (e.g., density, age, etc.). The methodology employs weighted matrices and a three-level ordinal scoring system designed to provide a practical and standardized assessment approach. Despite values presented in the matrix that are based on the established literature, their assignment unfortunately can still reflect a certain level of inherent subjectivity. Physical, morphological, and biological residual hazards are obtained, and the integrated residual risk is then calculated to provide an overall safety classification for each beach. Following a conservative risk-management approach, the governing domain principle corresponds to the maximum obtained risk. The resulting risk index serves as a valuable tool for beach managers to have a general view on beach safety at a regional scale. Further detailed site-specific investigations are required to precisely determine beach users’ risk within each sector, taking into account that meteo-marine conditions and visitor density fluctuate continuously throughout the day. The framework was applied to five representative beaches along the Atlantic coast of Cádiz (SW Spain) as a proof-of-concept application. The five case studies recorded risk values ranging from Low to Moderate Risk, illustrating the capability of the framework to generate differentiated assessments under contrasting environmental, management and exposure conditions.