Coastal groundwater is rising due to sea-level rise, becoming saltier and more corrosive, which is exacerbating corrosion and failure of critical infrastructure such as sewer lines, roadways, and building foundations. A study by earth scientists at the University of Hawai’i highlights the impact of shallower and saltier groundwater on buried infrastructure in coastal cities worldwide. The research aims to create awareness about these issues and provide guidance on managing them, as sea level rise is expected to continue for centuries to millennia.
The subsurface environment becomes more corrosive as sea-level rise pushes up the water table and shifts salty water landward, affecting critical underground infrastructure networks. This concealed damage can compromise drainage and sewer lines, mobilize urban contamination, and weaken building foundations, leading to extensive flooding before visible surface effects appear. The Climate Resilience Collaborative at UH Manoa has conducted research indicating that infrastructure worldwide, including drainage systems, is likely experiencing flooding from rising groundwater levels.
The study emphasizes the importance of understanding and addressing the hidden impacts of sea level rise on coastal groundwater, particularly in low-lying coastal cities where groundwater is shallow. In Hawai’i, where many communities are situated along coastal zones, it is crucial to be aware of these impacts in infrastructure management and planning efforts. Collaborations with partners and infrastructure managers are essential to assess the impacts and risks associated with sea level rise-influenced coastal groundwater and develop effective management and adaptation strategies.
The research team reviewed existing literature and utilized elevation and geospatial data to identify 1,546 low-lying coastal cities globally, where around 1.42 billion people live, experiencing the impacts of rising coastal groundwater. Sea level rise is predicted to be an unstoppable and irreversible reality, necessitating proactive measures to redesign communities for greater resilience and social equity. Managing the interactions between coastal groundwater and buried infrastructure is essential for mitigating the detrimental effects of sea level rise on infrastructure systems and ensuring the sustainability of coastal cities worldwide.
The damage caused by sea level rise-influenced coastal groundwater is often hidden and goes unnoticed, leading to challenges in infrastructure management and planning efforts. It is crucial to raise awareness of these impacts and incorporate them into adaptation strategies to address the challenges posed by rising sea levels. By understanding and addressing the impacts of sea level rise on coastal groundwater, communities can better prepare for the future and ensure the resilience of critical infrastructure systems. Collaboration and research efforts are essential in informing management strategies and developing effective adaptation measures to mitigate the impacts of sea level rise on coastal cities globally.
