Understanding seawater intrusion. [Poster]

Abstract

Seawater intrusion is the landward advance of seawater into freshwater aquifers, involving complicated density-dependent flow and salt transport process that are challenging to characterise and manage. Seawater intrusion is most induced by groundwater pumping, but can also occur from sea-level rise, changes in long-term recharge rates, seawater overtopping (e.g. due to tsunamis), and land-use activities such as canal developments. The widespread occurrence of seawater intrusion in coastal aquifers globally requires an elementary explanation of this complex phenomenon, to provide a framework for understanding and discussion amongst water resource managers, scientists, students, and others interested in the topic of coastal groundwater sustainability. This poster aims to address this by using coastal aquifer conceptual models to explain the complex nature of seawater intrusion, and to highlight a range of related issues, which include causal factors, ocean-groundwater interactions (e.g. tidal effects), methods of investigation, and management techniques.