Beyond coastal protection: A robust approach to enhance environmental and social outcomes of coastal adaptation

Hard coastal protective infrastructure, such as breakwaters, are a common adaptation strategy to protect assets, increase safety and improve navigation by reducing erosion and flood risks along coastlines globally. However, protective structures can have pervasive impacts on use patterns, aesthetics and associated ecosystems, threatening ecosystem goods and services upon which humans depend. Guided by a recent Australian state Government strategy that aims to plan for a healthy coast and sea managed for the greatest wellbeing of the community, now and into the future, we present a decision-making support tool for practitioners to help achieve more sustainable solutions to coastal adaptation into the future. Sustainable coastal adaptation needs to consider the environmental and socio-economic consequences of hard protective infrastructure, as well as the increased vulnerability due to rising sea levels. To demonstrate our arguments, we introduce three different coastal scenarios. We also discuss alternatives to coastal protection and make scenario-specific recommendations to enhance environmental and socio-economic outcomes of coastal adaptation. In general, the implementation of hard protective infrastructure should probably be a last resort after retreat and soft approaches have been ruled out as viable options. Where protective infrastructure is the current best option, environmental and socioeconomic outcomes can be enhanced using eco-engineering and multi-use features. In the long term, however, retreat from some coastal areas may be necessary and existing infrastructure might be removed or abandoned.

Automated summary

Hard coastal protective infrastructure, such as breakwaters, are commonly used to protect coastlines, but they can have negative impacts on ecosystems and aesthetics. To achieve more sustainable coastal adaptation, a decision-making support tool is presented, considering environmental and socio-economic consequences. Retreat and soft approaches should be considered before implementing protective infrastructure.