Q13.Seawater intrusion in the coastal aquifers is a major concern in India. What are the causes of seawater intrusion and the remedial measures to combat this hazard?

Seawater intrusion, the ingress of saline water into coastal freshwater aquifers, degrades groundwater quality and threatens potable water supply in India.

• Over-extraction: Excessive groundwater pumping for agriculture, industry, and domestic needs lowers freshwater levels.
• Sea-Level Rise: Climate change-induced sea-level rise increases saline water pressure.
• Reduced Recharge: Decreased rainfall and altered river flows diminish natural aquifer replenishment.
• Geological Factors: Permeable coastal geology facilitates easier intrusion.

• Managed Aquifer Recharge (MAR): Artificial recharge creates a hydraulic barrier.
• Groundwater Regulation: Strict abstraction limits, permits, and monitoring.
• Physical Barriers: Subsurface dams or injection wells impede saline water.
• Alternative Sources: Desalination and rainwater harvesting reduce groundwater dependency.
• ICZM & Awareness: Integrated Coastal Zone Management and public awareness for sustainable use.

An integrated approach, combining technology, stringent policies, and community participation, is crucial for combating this hazard and ensuring coastal water security.