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

Introduction: Coastal erosion is the wearing away and landward retreat of the shoreline that occurs when sediment loss outpaces sediment supply. A large share of India's roughly 7,500 km mainland coast is under erosion, mapped by the National Centre for Coastal Research, with the east coast the worst affected.

Body:

• Causes: Natural drivers include wave action, storm surges, cyclones and rising sea levels. Human drivers often dominate — dams and barrages starve rivers of sediment, ports, harbours and groynes interrupt the longshore drift of sand, sand mining strips the protective buffer, and the destruction of mangroves and coral reefs removes natural shock-absorbers.
• Effects: Outcomes include land and beach loss, saltwater intrusion into freshwater aquifers, displacement of fishing and coastal communities, damage to ports, coastal roads, settlements and tourism infrastructure, increased flooding during high tides, and the loss of mangrove, seagrass and turtle nesting habitat that further weakens future resilience.
• Management techniques: Hard engineering — seawalls, groynes, breakwaters and revetments hold the line but tend to shift erosion downdrift. Soft and eco-measures — beach nourishment, sand-filled geotextile tubes, dune restoration and mangrove bio-shields work with natural processes. Planning measures — Shoreline Management Plans, hazard-line mapping and the CRZ regime decide where to protect, accommodate or retreat.

Conclusion: Hard walls alone merely displace the problem along the coast. India's better path lies in sediment-cell-based Shoreline Management Plans that blend nourishment, bio-shields and managed retreat.