In December 2024, the Union Ministry of Home Affairs reported a significant revision in India’s coastline length.

• The length of the coastline was re-assessed by the National Hydrographic Office (NHO) in coordination with the Survey of India (SoI).
• The coastline increased from 7,516.6 km (1970s) to 11,098.8 km (2023-24) showing  a 47.6% increase.

• The change is not due to territorial expansion or geological shifts, but due to improved measurement methodologies.
• Coastline data will now be updated every 10 years, starting from 2024–25.

Geographical Coverage of India’s Coastline

• Coastal Boundaries: Bordered by Bay of Bengal (east), Arabian Sea (west) and Indian Ocean (south).
• Coastal States and Union Territories
• • States: Gujarat, Maharashtra, Goa, Karnataka, Kerala, Tamil Nadu, Andhra Pradesh, Odisha, West Bengal
  • Union Territories: Daman & Diu, Lakshadweep, Puducherry, Andaman & Nicobar Islands.

States/UTs with Significant Growth

• Gujarat: Increased from 1,214 km to 2,340 km
  • Largest absolute increase; retains longest coastline status.
• West Bengal: Increased from 157 km to 721 km.
  • 357% increase – highest in percentage terms.
• Tamil Nadu: Increased from 906 km to 1,068 km
  • Overtakes Andhra Pradesh in coastline length.

States/UTs with Minimal or Negative Growth

• Kerala: Increased by only 30 km (5%) – the smallest increase.
• Puducherry: The coastline was reduced by 4.9 km (-10.4%), due to erosion and recalibration.

Impacts of Coastline Expansion

• Economic and Developmental Implications
• • Ports & Logistics: States like Andhra Pradesh are expanding port infrastructure (e.g., Ramayapatnam, Krishnapatnam, Kakinada).
  • Maritime Economy: Longer coastlines boost fishing zones, tourism, and maritime trade.
• Strategic and Environmental Planning: Accurate coastline data is crucial for maritime security, infrastructure planning, and disaster preparedness.
  • Maritime Security: Larger coastline requires expanded coastal surveillance and protection.
  • Disaster Management:Crucial for cyclone alerts, tsunami readiness, and coastal zoning.
  • Environmental Monitoring: Enhances ability to track erosion, accretion, and biodiversity patterns.