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Combating Coastal Erosion
The ICZM scheme in India involves multiple states and is one of the most recent attempts to implement a holistic plan for large shorelines in regions severely stressed by the consequences of coastal erosion compounded by climate change. Its initial implementation in the states of Gujarat, Orissa, and West Bengal has been successful. Box 5.7 describes the overall ICZM scheme in more detail.
BOX 5.7
The World Bank supported the government of India in building capacity for the implementation of a comprehensive coastal management approach beginning in 2010. The first component of the project included mapping, delineation, and demarcation of hazard lines together with the delineation of coastal-sediment cells along India’s main coast. The other three components were (a) piloting of integrated coastal zone management (ICZM) approaches in the states of Gujarat, Orissa, and West Bengal; (b) building the capacity of agencies and institutions at the state level; and (c) training technical and administrative staff in ICZM planning and implementation. The project included pilot investments to protect coastal assets while also protecting and enhancing biodiversity at various sites (for example, through mangrove-shelterbelt plantations) as well as investments in better waste management and improvement in the livelihoods of coastal communities (for example, by promoting small-scale ecotourism).
In the course of the project, more than 7,800 kilometers of India’s mainland coast were mapped, delineated, and classified in the coastal hazard line—that is, the line of likely impact from natural hazards— to implement policies to protect coastal assets and communities from the adverse effects of disaster risks, including coastal erosion. The example shown in map 5.4 involves identifying different policy options for different parts of the shoreline together with detailed recommendations on the most promising interventions. For example, measures in intervention zones— that is, Permanent Coastal Location (PCL) 72 to PCL 77—included a combination of mangrove afforestation, installing lowslope revetment walls behind the shore, and beach nourishment to reduce the pressure of erosive forces and limit the risk of inundation during storm events (IPE Global 2018).
The preparation of plans and pilot activities in the states of Gujarat, Orissa, and West Bengal was highly participatory. Nearly 72,000 local inhabitants and 2,500 representatives of stakeholder groups were engaged, including government agencies, the private sector, fishing communities, and other members of civil society as well as tourists (World Bank 2020a). Emphasis was given to activities with the dual advantage of reducing erosive processes
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BOX 5.7
while benefiting biodiversity. About 19,500 hectares of mangroves were restored or planted, acting as coastal carbon sinks while protecting coastal assets and enriching local biodiversity.
A project in Pentha, Odisha, demonstrated the merits of Geotube technology (further described in the subsection on hard defenses below). It involves 505 meters of geotextile tubes along the Pentha village coast that act as a bund against tidal wave actions and mitigate erosive forces. It protects the lives and livelihoods of more than 40,000 residents as well as around 250,000 tourists who visit annually (World Bank 2020a). In addition to helping the village withstand the severe cyclones Phailin, Hud Hud, and Fani that hit Odisha in 2019, it has contributed to the restoration of the beachfront (Technical Textiles 2020).
Following the successes in developing the ICZM plan for India, the World Bank in April 2020 approved a multiyear US$400 million financing envelope to further support coastal states in India in enhancing the resilience of their coastal resources and populations. In the first phase, around US$180 million was provided to the Enhancing Coastal and Ocean Resource Efficiency (ENCORE) project, which will cover eight coastal states (Andhra Pradesh, Goa, Gujarat, Karnataka, Kerala, Odisha, Tamil Nadu, and West Bengal) as well as three coastal union territories (Daman and Diu, Lakshadweep, and Puducherry) where coastal resources are under significant pressure (World Bank 2020b).
Zoning plans as part of ICZM schemes have also become an important part of regional initiatives to efficiently address more-local coastal erosion issues. The ICZM plan for the beaches near Mundesley Beach in Norfolk, UK, is an example of such an intervention scheme. The region and its beaches are severely affected by coastal erosion, and local authorities have been planning and implementing erosion protections in various forms since the 1940s. In-depth studies have assessed the risks of coastal erosion on local municipalities (Dawson et al. 2009; Dickson, Walkden, and Hall 2007).
The ICZM plan divides the coast into three types of zones, each with a dominant policy intervention: doing nothing, holding the line, or maintaining existing defenses (but once the defenses are projected to fail, then strategically retreating). It also assigns different priorities to different localities—for example, the protection of the Bacton gas terminal, compared with the longer-term protection of Mundesley itself. Furthermore, because of the national importance of the Bacton gas terminal, both the short-term (0–20 years) and medium-term (20–50 years) policies are to
hold the line (because the terminal’s lifetime can reach up to 50 years) along with other interventions such as maintaining existing defense infrastructure and introducing a large volume of sediments starting in 2018 (Norfolk Vanguard Limited 2018).
Even when there are no plans to protect, other strategies should be considered. For example, the ICZM zoning plan for Mundesley Beach considers no protective measures for the coast along the village of Happisburgh—that is, the plan is to do nothing. However, this does not necessarily imply that no strategies are under consideration to address the coast’s erosion and the risk that near-shore properties will be destroyed. Providing inhabitants of these properties with clearly defined adaptation strategies in advance reduces the pain of eventual relocation. A clear strategy for the abandonment of land that cannot be saved provides the various stakeholders with a perspective that enables them to plan accordingly.
Support measures for displaced persons include buyout schemes, subsidies for the relocation process, and purchasing or building new developments elsewhere that are safe. This was done in Happisburgh. Properties considered to be at immediate risk of erosion were purchased from the residents, and they were simultaneously granted an automatic planning right to replace their homes on the landward side of the village. Similarly, the cliff-top caravan park, which is an important source of income, was relocated farther inland (Kerby 2019).
Reactive Management and Control Measures
Stakeholders or policy makers can adapt existing structures to coastal erosion and manage coastal erosion in two ways: (a) defend the coast with “hard solutions” like seawalls or “soft solutions” such as beach nourishment, including natural and NBS such as mangrove restorations; or (b) implement control policies for development purposes or directly for sediment-balance purposes. These two options of defense and control policies are discussed in more detail below.
Defense Solutions
The range of possible measures to address coastal erosion and defend shorelines and settlements can be categorized as hard-defense solutions or soft-defense solutions (including NBS). All these measures aim to reduce or absorb the erosive forces of currents and waves but differ in their integration with the natural environment. The specific implementation of one measure or another is highly case-specific and depends on local characteristics but should be coordinated, ideally in a comprehensive action plan designed under the tenets of ICZM.
