What is a consequence of saltwater intrusion in coastal aquifers?

Saltwater intrusion occurs when seawater encroaches into freshwater aquifers, particularly in coastal areas where freshwater resources are extracted faster than they are replenished. This phenomenon primarily arises from excessive groundwater pumping, which reduces the water pressure that keeps saltwater at bay. As a result, the freshwater layer becomes thinner, allowing saltwater to mix with the freshwater supply.

The consequence of this intrusion is a significant reduction in the availability of freshwater. As saltwater infiltrates the aquifer, the quality of the water deteriorates, making it unsuitable for drinking, irrigation, and other uses. This can lead to challenges in maintaining water supply for communities, agriculture, and ecosystems that rely on fresh water. It underscores the importance of sustainable water management practices to protect coastal aquifers from such detrimental effects.

In contrast, the other choices do not accurately reflect the impact of saltwater intrusion. Increased water supply would not occur; instead, there is a finite limit on freshwater availability. Improved irrigation practices and enhanced groundwater recharge are also unlikely outcomes in the context of saltwater intrusion, as the primary issue is the degradation of the existing freshwater resources rather than an enhancement or increase in water quality or quantity.