India’s coastline has been officially recalculated as 11,098.81 km, up from the previously accepted 7,561.60 km—an increase of 3,537.21 km or nearly 50%. This revision results from a change in measurement methodology, as per a circular issued by Union Shipping Ministry.
Key Highlights
- Previous coastline length: 7,561.60 km (since the 1970s).
- Revised coastline length (2024): 11,098.81 km.
- Reason for change: Update in measurement method, not a physical expansion.
- The revised length will be reviewed every 10 years using updated datasets.
- Purpose: To improve planning for coastal security, infrastructure, climate change adaptation, and maritime boundary management.
Why the Increase?
Methodology Update
- Earlier method:
- Used straight-line mapping.
- Based on outdated maps at scales like 1:4,500,000 or smaller.
- New method:
- Uses Electronic Navigation Charts (ENCs) by the National Hydrographic Office (NHO).
- Measures the High-Water Line (HWL) at 1:250,000 scale.
- Aligned with WGS-84 datum and UTM zones.
- Includes detailed coastal features: bays, estuaries, river mouths, backwaters, tidal linkages, and offshore islands.
- Larger map scales capture more details, increasing total measured length.
Inclusion of Offshore Islands and Islets
- A major factor behind increase: 1,298 offshore islands and islets included for the first time: 1,059 islands and 239 islets.
- Earlier mapping excluded many islands due to scale limitations and manual measurement constraints.
- High-resolution GIS tools were used to map even minor coastal contours.
Background
- Since the 1970s, the Ministry of Home Affairs reported India’s coastline as 7,561 km.
- Different government departments used varying coastline figures.
- Issue formally examined in 2019.
- The Coastal Protection and Development Advisory Committee (CPDAC) has been discussing this since 2010.
- January 2024: Coastal states and UTs reviewed and accepted the updated coastline.
- September 2024: Meeting chaired by the Surveyor General of India confirmed reasons for variations and finalized publication of the new length.
- Final approval given during a high-level meeting at the National Security Council Secretariat (NSCS).
State-wise Coastline Length (Revised 2024 Data)
| State/UT | Coastline Length (km) |
| Gujarat | 2,340.62 |
| Maharashtra | 877.97 |
| Goa | 193.97 |
| Karnataka | 343.30 |
| Kerala | 600.15 |
| Tamil Nadu | 1,068.69 |
| Andhra Pradesh | 1,053.07 |
| Odisha | 574.71 |
| West Bengal | 721.02 |
| Daman & Diu | 54.38 |
| Puducherry | 42.65 |
| Lakshadweep Islands | 144.80 |
| Andaman & Nicobar Islands | 3,083.50 |
| Total | 11,098.81 |
Why It Matters?
- Provides more accurate data for:
- Coastal security planning.
- Infrastructure development.
- Climate change mitigation.
- Maritime boundary management.
- Helps align government policies with the actual coastal geography.
- Enhances coordination among central and state agencies.
- Boosts India’s ability to manage its maritime domain awareness.
- Supports disaster preparedness (like cyclones, coastal erosion).