Coastal Erosion in India – Causes & Consequences – Explained Pointwise

Recently, in response to a question raised in the Rajya Sabha, the Union Minister for Ports, Shipping and Waterways stated that about 28% of Odisha’s 564-km coastline is experiencing erosion, based on a study by the National Centre for Coastal Research (NCCR). The NCCR monitors long-term shoreline changes along India’s coastline.

What is coastal erosion?

• Coastal Erosion refers to the loss of land, long-term removal of sediment and rocks along the coastline due the action of sea-waves, currents, tides and other impacts of storms.
• It involves wearing away and redistributing solid elements of the shoreline as well as sediment. Erosion occurs when the material being removed, for deposition elsewhere, exceeds the rate of supply finally resulting in the landward shifting of the shoreline.
• Key processes involved:
  1. Hydraulic action: The force of waves striking the coast compresses air in cracks and crevices of rocks, weakening and eventually breaking them apart.
  2. Abrasion (corrasion): Waves carry sand, pebbles, and rock fragments that grind against cliffs and shorelines, wearing them down like sandpaper.
  3. Attrition: Rock fragments and sediments carried by waves collide with each other, breaking into smaller, smoother particles over time.
  4. Corrosion (solution): Chemical weathering where seawater dissolves soluble rock materials like limestone and chalk.
  5. Longshore drift: Waves approaching at an angle move sediment along the coast, redistributing material and altering shoreline shape.

What is the extent and spatial distribution of coastal erosion in India?

• India has a 7,517-km coastline, including the mainland and islands. Coastal erosion is a major concern because of rising sea levels, cyclones, changing sediment flows and human interventions along the coast.
• According to the National Centre for Coastal Research (NCCR) assessment for 1990-2018, about 6,907 km of India’s mainland coastline was analysed. The findings show:
  

  Shoreline status	Share of mainland coastline
  Eroding	33.6%
  Accreting	26.9%
  Stable	39.6%

• Spatial Distribution:
  

  Eastern Coast	Easter coast has relatively higher vulnerability. Approximately 38% of the shoreline is eroding. West Bengal: particularly vulnerable, with about 60.5% of its analysed coastline experiencing erosion. Odisha: around 28.3% was under erosion. Andhra Pradesh: around 28.7%. Tamil Nadu: around 42.7%. Puducherry: about 56.2%.
  Western Coast	Western coast is relatively stable. Approximately 30% of the shoreline is eroding, with more than 48% remaining stable due to rocky headlands and Deccan basalt configurations. Kerala is among the most affected major coastal states, with approximately 46.4% of its coastline showing erosion. Gujarat: about 27.6%. Maharashtra: about 25.5%. Karnataka: about 23.7%. Goa: about 19.2%.

• Thus, nearly one-third (33.6%) of India’s mainland coastline experienced varying degrees of erosion during 1990-2018.

What are the major causes of coastal erosion in India?

What are the major impacts of coastal erosion in India?

1. Loss of Coastal Land: Coastal erosion causes progressive retreat of the shoreline, resulting in the loss coastal land. It threatens low-lying settlements, particularly in densely populated coastal regions, while increasing the risks of inundation, displacement and loss of productive land. For e.g. the submersion of Satabhaya village in Kendrapara (Odisha) and the rapid shrinking of Ghoramara, Mousuni, and Sagar Islands in the Indian Sundarbans (West Bengal).
2. Loss of Livelihoods: Coastal erosion threatens the livelihoods of fishing and farming communities by reducing access to beaches, fishing grounds and agricultural land. Damage to coastal infrastructure, aquaculture and tourism further affects incomes, while displacement forces communities to seek alternative sources of employment. For e.g. In Kerala, fishers lose direct access to the sea, forcing them to commute to distant, congested commercial harbors.
3. Damage to Infrastructure: Coastal erosion undermines roads, bridges, ports, railway lines, power infrastructure, houses and other public assets located near the shoreline. For e.g. National and State Highways (such as the East Coast Road in Tamil Nadu and sections of NH-66 in Kerala/Karnataka) face periodic collapse during monsoon swell waves and cyclones.
4. Displacement of Coastal Communities: Coastal erosion causes gradual loss of homes & agricultural land, forcing fishing and coastal communities to relocate. Such displacement can lead to loss of livelihoods, social networks, cultural identity and economic security, creating challenges of rehabilitation and resettlement.
5. Salinity Intrusion: Shoreline retreat and sea-level rise can facilitate the intrusion of seawater into groundwater and agricultural land, affecting drinking water and crop productivity. For e.g. Coastal populations in states like Tamil Nadu and Andhra Pradesh face acute shortages of potable drinking water, forcing local panchayats to rely on water tankers or expensive desalination.
6. Loss of Coastal Ecosystems: Coastal erosion damages mangroves, coral reefs, sand dunes, beaches and wetlands, leading to habitat loss and declining biodiversity. For e.g. coastal erosion flattens and shrinks the mass-nesting beaches (arribada) of vulnerable Olive Ridley turtles at Rushikulya, Gahirmatha, and Devi river mouths in Odisha.
7. Economic Losses: Coastal erosion causes substantial economic losses by damaging houses, roads, ports, tourism infrastructure and agricultural land. NCSCM estimates that around 100 sq km of beach/coastal land has been lost, while annual economic losses associated with erosion have been estimated at around ₹1,000 crore in protection and mitigation-related costs.
8. Impact on Tourism: Coastal erosion leads to the loss and degradation of beaches, dunes and scenic landscapes, reducing the attractiveness of coastal destinations. It can damage tourism infrastructure, increase maintenance costs, and adversely affect local businesses and employment dependent on tourism.

What measures has the government taken to address coastal erosion in India?

1. Shoreline Mapping and Monitoring: The National Centre for Coastal Research (NCCR) monitors shoreline changes using satellite imagery, remote sensing and field surveys to generate the Shoreline Change Atlas of India. It has mapped vulnerable stretches and provides technical support to coastal States/UTs.
2. Shoreline Management Plans: NCCR assists States in preparing Shoreline Management Plans (SMPs). These plans identify high-, medium- and low-erosion zones and recommend site-specific protection measures rather than a uniform approach.
3. Coastal Regulation Zone (CRZ) Notification, 2019: The CRZ framework regulates development along vulnerable coastal stretches. It provides for No Development Zones (NDZs) in specified areas and seeks to protect ecologically sensitive areas such as mangroves and coral reefs.
4. Demarcation of Hazard Lines: The government has delineated a hazard line along India’s coast, considering shoreline changes, flooding and sea-level rise. It is used for disaster management, land-use planning and adaptation measures.
5. Disaster Risk Financing: The 15th Finance Commission recommended ₹1,500 crore under the National Disaster Mitigation Fund (NDMF) for structural and non-structural measures to mitigate coastal and river erosion. ₹1,000 Crore allocated under the National Disaster Response Fund (NDRF) dedicated to the resettlement and rehabilitation of populations displaced by coastal and river erosion.
6. Ecosystem-Based Adaptation (Soft Engineering):
   1. MISHTI Scheme (2023-2028): The Mangrove Initiative for Shoreline Habitats & Tangible Incomes targets the restoration and afforestation of ~540 sq. km of mangrove buffers across 11 coastal states and 2 UTs by converging MGNREGS, CAMPA funds, and local community stewardship.
   2. Bio-Shield Plantations: State forest departments systematically plant shelterbelts of Casuarina equisetifolia, Pandanus, and sand-binding creepers to stabilize coastal dunes and reduce wind-wave impact.

What should be the way forward?

1. Adopt Integrated Coastal Zone Management (ICZM): ICZM promotes coordinated management of coastal resources by balancing economic development, environmental conservation and livelihood security. It integrates land-use planning, disaster risk reduction, ecosystem protection and community participation to ensure sustainable and climate-resilient development along India’s vulnerable coastline.
2. Prepare and implement Shoreline Management Plans: Develop science-based, site-specific plans using shoreline-change data, sediment dynamics, hazard mapping and stakeholder inputs. These plans should guide suitable protection measures while balancing coastal development, ecosystem conservation and community livelihoods.
3. Strengthen Coastal Regulation: Strictly enforce Coastal Regulation Zone (CRZ) norms, prevent unplanned construction in vulnerable areas, regulate sand mining and coastal activities, and integrate hazard-line mapping into land-use planning to reduce long-term erosion risks.
4. Improve Climate Resilience: Integrate sea-level rise, cyclones, and storm surges into coastal planning, infrastructure design and disaster management. Also strengthen the early-warning systems, ecosystem-based adaptation and climate-resilient livelihoods.
5. Prioritize Nature-Based Solutions (NbS): Restore mangroves, coral reefs, sand dunes, wetlands and coastal vegetation as natural barriers. For e.g. Expand mangrove and shelterbelt afforestation, particularly in the Sunderbans, Godavari-Krishna delta, and Kerala because mangroves are more cost-effective and self-sustaining than seawalls.
6. Community-Centred Approach: Involve coastal communities, particularly fishermen, in planning and decision-making, while providing livelihood support, disaster preparedness, insurance and rehabilitation assistance.

Conclusion: Coastal erosion in India is both an environmental and developmental challenge. We need to shift from reactive protection to integrated coastal management, combining nature-based solutions, resilient infrastructure, scientific planning and community participation, to build climate-resilient and sustainable coastal regions.