Groundwater Dynamics in Coastal Aquifers Under Climate Change

Coastal aquifers serve as crucial freshwater reserves for millions of people worldwide, yet they are increasingly vulnerable to the multifaceted impacts of climate change. Rising sea levels, altered precipitation patterns and more frequent extreme weather events combine to elevate water tables, exacerbate saltwater intrusion and disrupt the delicate balance between freshwater recharge and discharge. In many low-lying regions, higher groundwater levels can emerge at the surface, leading to unseen inundation of subsurface infrastructure and soils, while progressive salinisation compromises water quality and ecosystem health. Understanding these dynamics requires an integrated perspective on hydrological processes, subsurface geology and human activities such as groundwater extraction and land-use change. As sea level continues to rise, coastal communities must reckon with both acute flooding risks and chronic declines in freshwater availability, driving an urgent need for improved monitoring, modelling and adaptive management strategies.

Research from Nature Portfolio

Recent studies have evaluated the impact of saltwater intrusion on civil infrastructure foundations under various sea-level rise scenarios. One investigation assessed corrosion risks in the steel reinforcement of residential building foundations across low-lying regions, projecting substantial repair costs by the end of the century. The analysis combined hydrogeological modelling with structural deterioration estimates to demonstrate how progressive salinisation of groundwater can precipitate unforeseen economic burdens and compound climate adaptation challenges for urban communities.

Groundwater Dynamics in Coastal Aquifers Under Climate Change publication trend

The graph below shows the total number of articles in groundwater dynamics in coastal aquifers under climate change across all publications each year (not limited to Nature Index journals).

Technical terms

Coastal aquifer: A groundwater reservoir in permeable subsurface materials bordering the sea, which is influenced by marine and terrestrial water balances.

Saltwater intrusion: The landward movement of seawater into a fresh groundwater system, driven by sea-level rise or excessive freshwater extraction.

Sea-level rise: The increase in the average global sea level, primarily due to thermal expansion of seawater and melting of land ice under climate warming.

Groundwater flooding: Inundation of land surface occurring when rising groundwater exceeds ground elevation, often following prolonged high water tables or sea-level rise.

Fresh–saltwater interface: The transitional zone within a coastal aquifer where fresh groundwater overlies and mixes with intruding saline water.

References

1. Hidden costs to building foundations due to sea level rise in a changing climate. Scientific Reports (2022).
2. Groundwater Rise and Associated Flooding in Coastal Settlements Due To Sea‐Level Rise: A Review of Processes and Methods. Earth's Future (2022).
3. Mega‐Tidal and Surface Flooding Controls on Coastal Groundwater and Saltwater Intrusion Within Agricultural Dikelands. Water Resources Research (2023).
4. The hidden consequences of sea level rise: assessing vulnerability of buried infrastructure to groundwater inundation in American Samoa. Journal of Water and Climate Change (2023).