Question = Explain the causes and effects of coastal erosion in India. What are the available coastal management techniques for combating this hazard?
Coastal erosion is the wearing away of land and removal of beach sediments by high winds, wave action, tidal currents and/or human activities, typically causing a landward retreat of the coastline. In India, coastal erosion is a major concern due to the country's long coastline of about 7516.6 km and the high population density in many coastal areas.
Some of the main causes of coastal erosion in India include:
Sea level rise: Global warming is causing sea levels to rise, which can lead to more frequent and severe erosion along the coast. Sea level rise can also increase the inundation of low-lying areas, reduce the sediment supply from rivers and alter the coastal morphology.
Wave action: Waves are the primary agent of coastal erosion, especially on the west coast of India, which is a submergent coast and hence highly vulnerable to erosion. Waves can erode the coast by hydraulic action, abrasion, corrosion and attrition. The wave energy and direction can vary depending on the wind speed, fetch, season and monsoon.
Tidal currents: Tidal currents are the horizontal movements of water caused by the gravitational forces of the moon and the sun. Tidal currents can erode the coast by transporting sediments alongshore or offshore, creating sandbars, spits, inlets and estuaries. Tidal currents can also interact with waves and storm surges to increase the erosive force.
Storm surges: Storm surges are temporary rises in sea level caused by low atmospheric pressure and strong winds associated with cyclones, hurricanes or typhoons. Storm surges can erode the coast by overtopping dunes, seawalls and other coastal structures, causing flooding, scouring and breaching. Storm surges can also increase the wave height and energy.
Human activities: Human activities such as dredging, sand mining, coral mining, construction of ports, harbours, jetties, groynes, seawalls and other coastal structures can contribute to coastal erosion by altering the natural sediment balance, modifying the water depth and flow patterns, disrupting the longshore drift and wave refraction, and reducing the natural resilience of the coast.
Some of the main effects of coastal erosion in India include:
Loss of land: Coastal erosion can result in loss of land area along the coast, which can affect agriculture, fisheries, tourism, infrastructure and human settlements. According to a study by National Centre for Coastal Research (NCCR), about 33% of India's coastline is eroding at an average rate of 0.38 m/year.
Loss of biodiversity: Coastal erosion can result in loss of biodiversity along the coast, which can affect ecosystem services, natural resources and human well-being. Coastal ecosystems such as mangroves, coral reefs, seagrasses and wetlands provide habitats for many species of flora and fauna, protect the coast from storms and waves, sequester carbon and support livelihoods.
Loss of heritage: Coastal erosion can result in loss of heritage along the coast, which can affect cultural values, historical sites and archaeological monuments. For example, coastal erosion has threatened the ancient shore temple at Mahabalipuram in Tamil Nadu, which is a UNESCO World Heritage Site.
Increased vulnerability: Coastal erosion can result in increased vulnerability of coastal communities to natural hazards such as storms, floods, tsunamis and sea level rise. Coastal erosion can also exacerbate social problems such as poverty, displacement, migration and conflicts over land and resources.
To combat coastal erosion in India, various coastal management techniques have been adopted or proposed at national and local levels. Some of them are:
Integrated Coastal Zone Management (ICZM): ICZM is a holistic approach that aims to balance the environmental, social and economic aspects of coastal development and conservation. ICZM involves planning, coordination and participation of various stakeholders such as government agencies, local communities, NGOs and private sector. ICZM also involves monitoring, evaluation and adaptation of policies and measures to changing conditions.
Coastal Regulation Zone (CRZ): CRZ is a legal framework that regulates the development activities along the coast within a specified zone based on ecological sensitivity. CRZ was first notified in 1991 under the Environment Protection Act 1986 and revised in 2011 and 2019. CRZ aims to protect and conserve the coastal environment and resources, and promote sustainable livelihoods for coastal communities.
Coastal Protection Measures (CPM): CPM are physical interventions that aim to prevent or reduce coastal erosion by stabilizing the shoreline, enhancing the sediment supply or dissipating the wave energy. CPM can be classified into hard structures and soft solutions. Hard structures are artificial constructions such as seawalls, groynes, breakwaters and revetments that reflect or deflect the waves. Soft solutions are natural or nature-based methods such as beach nourishment, dune restoration, mangrove plantation and artificial reefs that absorb or dissipate the waves.
These are some of the causes and effects of coastal erosion in India, and the available coastal management techniques for combating this hazard.
What are some challenges in implementing ICZM and CRZ in India?
Integrated Coastal Zone Management (ICZM) is a holistic approach that aims to balance the environmental, social and economic aspects of coastal development and conservation. Coastal Regulation Zone (CRZ) is a legal framework that regulates the development activities along the coast within a specified zone based on ecological sensitivity.
Some of the challenges in implementing ICZM and CRZ in India are:
Lack of scientific data and information: ICZM and CRZ require reliable and updated data and information on various aspects of the coastal zone, such as geomorphology, hydrology, ecology, socio-economy, hazards, climate change etc. However, there is a lack of adequate data and information on these aspects, especially at the local level, which hampers the planning, monitoring and evaluation of ICZM and CRZ.
Lack of coordination and integration: ICZM and CRZ involve multiple stakeholders from different sectors, levels and jurisdictions, such as central, state and local governments, private sector, NGOs, academic institutions and coastal communities. However, there is a lack of effective coordination and integration among these stakeholders, which leads to conflicts of interest, overlapping mandates, duplication of efforts and gaps in implementation.
Lack of capacity and awareness: ICZM and CRZ require adequate capacity and awareness among the stakeholders to understand the concepts, principles and practices of ICZM and CRZ, and to carry out their roles and responsibilities effectively. However, there is a lack of sufficient capacity and awareness among the stakeholders, especially at the state and local levels, which affects their participation, compliance and enforcement.
Lack of financial resources: ICZM and CRZ require adequate financial resources to support the various activities and interventions related to coastal development and conservation. However, there is a lack of sufficient financial resources for ICZM and CRZ, especially at the state and local levels, which limits their implementation and sustainability.
Lack of public participation: ICZM and CRZ require active public participation from the coastal communities and other stakeholders to ensure their ownership, acceptance and support for ICZM and CRZ. However, there is a lack of effective public participation in ICZM and CRZ, due to factors such as lack of awareness, access to information, consultation mechanisms, grievance redressal mechanisms etc.