What does saltwater intrusion involve?

Saltwater intrusion refers specifically to the process whereby saline water moves into freshwater aquifers, typically as a result of excessive pumping of groundwater from these aquifers. When freshwater is removed at a rate faster than it can be replenished, the hydrostatic pressure decreases, allowing saltwater, which is denser, to encroach into the freshwater supply. This phenomenon is particularly prevalent in coastal areas where freshwater aquifers are adjacent to saline water bodies such as oceans and seas.

Understanding the mechanics of saltwater intrusion is crucial for water resource management, especially in the face of rising sea levels and increasing freshwater demand from urban populations. Mitigating the effects of this intrusion is vital for ensuring that aquifers remain a sustainable source of drinking water.

In contrast, movement of freshwater into saline aquifers, purification processes, and construction of barriers pertain to different aspects of water management and do not define saltwater intrusion itself.