Explain the causes and effects of coastal erosion in India. What are the available coastal management techniques for combating the hazard? (UPSC 2022)

Coastal erosion in India is the gradual loss of land along the shoreline due to the removal of sand and sediments by waves, currents and storms. It is a serious hazard because nearly one-third of the mainland coast is erosion-prone, threatening settlements, ports and fragile ecosystems.

• Causes
  • Natural factors: cyclones, storm surges, high waves, tidal currents and longshore drift shift beach material; sea-level rise worsens this process.
  • Sediment starvation: dams and river regulation reduce the supply of sand to deltas and beaches.
  • Coastal structures: ports, harbours, groynes and breakwaters interrupt natural sediment movement, causing erosion down-drift.
  • Human pressure: sand mining, unplanned construction and destruction of mangroves, dunes and coral reefs weaken natural protection.
• Effects
  • Loss of land, homes and farmland, forcing displacement of coastal communities.
  • Damage to roads, embankments, tourist beaches, fisheries assets and port infrastructure.
  • Saline intrusion into groundwater and loss of wetlands, nesting sites and biodiversity.
  • Livelihood stress for fishers who lose space for boat landing, net drying and fish processing.
• Management techniques
  • Hard engineering: seawalls, revetments, groynes, breakwaters and geotextile tubes for immediate protection.
  • Soft engineering: beach nourishment, dune stabilisation and sand bypassing to restore sediment balance.
  • Eco-based measures: mangrove restoration, coral and dune conservation as bio-shields.
  • Planning and regulation: hazard line mapping, Coastal Regulation Zone norms, and restriction on risky construction.
  • Institutional support: targeted mitigation and rehabilitation funds, alongside community-based preparedness and relocation where needed.

A balanced strategy is essential: hard structures may save assets in the short term, but long-term resilience depends on sediment management, ecosystem restoration and stricter coastal planning.