With the present breakwater and seawall constructions worsening sea erosion scenario in Kerala, a group of scientists have called for nature-based defence mechanisms like sand dunes, mangroves and native vegetation.
“The emerging concept of living shore should be adopted in the area,” the scientists said in their independent review “Seashore Erosion in Kerala: Review and Recommendations”.
Dr Biju Kumar A, Professor and Head, Department of Aquatic biology and Fisheries, University of Kerala, Dr KV Thomas, former Chief Scientist and Head, National Centre for Earth Sciences, Dr Ajayakumar Varma, former Chief Scientist and Head, Natural Resources and Environmental Management, National Centre for Earth Sciences, Dr Shaji, Associate Professor and Head, Department of Geology, University of Kerala and Dr T V Sajeev, Senior Principal Scientist, Kerala Forest Research Institute carried out the study.
The study points out the importance of securing the kerala shores with respect to the current and predicted climate change impacts threatening the very existence of seashore communities. They noted that many of the solutions for kerala sea shore erosion only aggravated the issue. “We need to evolve better solutions, taking into consideration the concerns of the people living on the shores, solutions which are based on nature and in tune with the integrated development of Kerala and climate-adapted. It is with this perspective that we need to work out kerala seashore management plan,” they said.
Immediate actions needed
- “Room for seashore” should be taken up as the slogan, and the decision to leave 50 m distance from the shoreline for the sea itself for ensuring the stability of beaches.
- Preparing list of hotspots based on available studies on kerala sea shore erosion and field verification report prepared by local self-governments. Based on the intensity of erosion, the seashore should be classified as: (a) Severely eroded seashore (where the erosion is intense and no management method is possible), (b) Highly eroded seashore (where erosion is intense but management is possible), (c) Moderately eroded seashore, (d) Slightly eroded seashore, (e) Seashore prone to erosion, and (f) erosion-free seashore.
- At the severely eroded kerala seashore, based on the importance of the landscape, hard structures will be needed. However, using granite for the purpose will lead to collateral damage which would cascade from the Western Ghats to the seashore. Use of reefs in shallow waters (as a primary defence), concrete wall, tetrapods, geotextile tubes, breakwater etc should be undertaken after Morphological Impact Assessment. Priority should be given to places where human settlements are close to the sea.
- Since the current breakwater and seawall constructions have worsened the kerala shore erosion scenario, better structural features should be adopted for seashore maintenance after careful study of the current status, and beach nourishment methods and sand bypassing should be considered wherever possible, after sitespecific studies, taking into account coastal geomorphology and dynamics.
- At locations with severe seashore erosion, people living within 50 m of the high tide line should be relocated to nearby locations with little or no impact on their livelihood options. The package developed by the fisheries department should be implemented in a time-bound manner. This has to be done in consultation with the community.
- In locations prone to sea erosion, only the traditional fishing community should be given permission for erecting new houses.
- Considering the sea wall construction was counterproductive, in one-third of the seashore with low erosion, nature-based solutions should be implemented. Sand dunes, mangroves, native vegetation etc. are natural defence mechanisms against seashore erosion. The emerging concept of “living shore” should be adopted in the area.
- At low erosion sites, locations prone to erosion and erosion free areas, nature-based solutions have to be implemented. A seawall with granite costs 4 crores per kilometre. Adding other hard structures to it will increase the budget by ten times. During covidinduced economic constraints, the solution to be looked forward is nature-based solutions implemented in a participatory manner.
Long-term actions
- Coastal erosion maps should be prepared with the participation of local communities and the scientific community.
- The concept of a ‘knowledge society’ being implemented by the Kerala government should be worked out along with decentralised governance so as to evolve a participatory seashore management plan.
- In order to bring in local specificities, participatory research projects should be mooted and funded towards erosion management. The local human resource capable of undertaking the work should be used for this. Prioritised socially relevant research projects on coastal zone management and mapping should be entrusted with research institutions.
- The coastal zone management plan should be implemented using marine spatial planning at the village level. The fishing community should be treated as ecosystem people, and their locations should not be used for other commercial activities.
- India is envisaging an integrated coastal zone management project. As part of this, local level participatory coastal zone management projects should be implemented. These projects should be led by the district level coastal zone management committees. Currently, the central/state coastal management authorities only take up the responsibility of granting permission to constructions on the coastal zone. However, their responsibility includes coastal zone conservation and management, too, which needs to be realised.
- The inefficient implementation of coastal zone conservation and management is the lack of integration across various agencies. There should be a coordination committee headed by the Chief Minister to resolve this, and to complete the projects in a timebound manner.
- Institutions like KILA (Kerala Institute of Local Administration) should conduct training for local self-government representatives using the expertise available at NCESS, KFRI, CWRDM, Universities and experts in the fields of Geology, Marine Sciences, Ecology etc. The services of green army, civil society organizations, and citizen scientists should also be used to prepare local-specific coastal zone management plans.
- To monitor violations of the coastal zone management Act, a Coastal zone monitoring network should be made linking civil society groups, environmental activists and linking all local self-governments in the coastal zone.
- Through integrative research, the ecosystem services of the coastal zone should be assessed, and sustainable management plans should be developed and implemented.
- Mining of strategically important mineral sand should be regulated strictly and should be done only by the public sector. Mudflats, coastal wetlands, mangroves and sandy beaches should be declared as Ecologically Sensitive Zone 1.
- Dredging will be necessary at ports. It has to be made sure that the mud and soil excavated are not used to reclamation coastal wetlands.
- At the hotspots / ESZ 1, sand mining should be prohibited. There should be a reliable enforcement mechanism for this.
- Shores, where the Olive Ridley turtles lay eggs, should be protected. The forest department should economically support hatcheries maintained by local people.
- New ports should be opened only after impact studies and consultation with the local communities. The efficiency of the existing ports should be enhanced.
- There should be grassroots level studies to evaluate and predict the impact of climate change to improve our knowledge base. A digital elevation model should be used to identify areas where climate change impacts would be severe. Along with this, institutional mechanisms to prepare flood maps and for flood prediction should be developed.
- To develop better coastal zone management, studies based on predictive models should be started. Based on a detailed study, climate adaptation methods should be developed for the coastal communities.
- Novel methods of house construction which can withstand sea level rise and coastal flooding should be evolved based on research. Areas with recurrent sea rise should have mutli-purpose rescue centres.
- The climate change possibility in the state should be integrated with the disaster management policy of the state. Climate change adaptation strategies need to be discussed and finalised in consultation with the local community, taking clues from their traditional wisdom as well.
- Nature-based solutions should be used to prepare green belt at the coastal buffer zone, and the activities should be linked to Rural Employment Guarantee programmes and food security schemes.
Factors that induce changes leading to seashore erosion
The Kerala sea shore degradation started in the 1950s. This was primarily due to unscientific constructions in the sea shore, the study said. These constructions, mostly harbour breakwaters, that ignored the ecotone landscape’s dynamic nature, made kerala sea shore degradation far and wide. The beach nourishment systems adopted the world over during the construction of harbours were not implemented, they said. Hard armouring structures like seawall aggravated the issue, they added. Apart from this, degradation of rivers, which brought sand and sediments to maintain kerala sea shore, also worsened the situation. The increasing number of hurricanes in the Arabian sea and the rising sea level is going to aggravate the situation, the study noted.