Preventing beach goers from drowning: analysis of geomorphological and human data to better understand factors leading to surf rescues

Abstract

AbstractGlobally rip currents are the primary physical hazard facing swimmers on surf beaches. However, beach swimmers also face other hazards such as large waves, tidal influenced currents, and shorebreak waves. The aim of this study was to investigate factors leading to the increased likelihood of surf lifeguard rescues. Rescue data from Surf Life Saving Queensland’s Lifesaving Incident Management System and Operations Console for 54 wave dominated beaches in South–East Queensland, Australia, from July 1st, 2016 to October 6th, 2021 was linked with wind speed and direction, air temperature, phase of tide, wave height and period, beach type, beach hazard rating, and beach swimmer numbers. Stepwise regression was performed to find independent predictors of rescue. There were 8515 rescues, with 3345 (39.3%) females and 5109 (60.0%) males (61 sex not recorded). There were no independent predictors of surf rescue but swimming outside the lifeguard patrol area was nine times more likely to result in rescue than swimming inside the patrol area. Increased rescues were noted at periods of increased rip activity. Rip currents (2992/6523, 45.8%) were the most frequently recorded contributing factor. Rescues occurred most frequently (5902, 69.3%) during the six hours of lower tide levels and during onshore winds (5463, 64.2%). Surf rescues increased with increasing wave height and period, air temperature, and wind speed but decreased as average values for each variable were surpassed. Beaches protected from the prevailing wave direction by headlands had a stronger relationship between rescues and wave height. Beaches adjacent to inlets with tidal flow had a stronger relationship between rescues and the ebb tide. Beach morphology, and hazard rating did not have a relationship with ratio of rescues per 100,000 swimmers. We found no independent predictors for surf rescue, however this study has, for the first time we believe, quantified the increased risk (× 9) posed by swimming outside the patrol area. Open beaches, beaches protected by headlands and beaches with tidal inlets all had different relationships between rescues, tides and wave size. Our findings suggest that lifeguards may need to adopt new approaches to prevent rescues adjacent to the patrol area, as well as a revision of the general hazard rating being required.