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Mitigate Coastal-Erosion Effects
FIGURE 5.4
Key Elements of Sustainable Coast Management to Mitigate Coastal-Erosion Effects
Stakeholder engagement Identification of erosion sources and hot spots
Integrated coastal zone management (ICZM) for mitigation of coastal-erosion effects
Data, monitoring, and analysis
Prospective management through zoning
Reactive management and control measures
Defense solutions
Control policies Hard defense, soft defense, and nature-based solutions
Development-related regulations and sediment-related regulations
Source: Original figure prepared for this publication.
(b) avoiding impacts where such defenses are not possible (by managing the retreat).
Complementary work on river-basin management may also be necessary because interference in natural processes—through reduction in river flow from abstraction for upstream water use, urbanization, loss of natural flooding regimes, and dam regulation—may all affect the flow of sediment to the coast. Regulatory controls may vary from banning sand mining to modifying dam operations in order to limit losses from trapped sediment. The “Comprehensive Policies and Actions for Reducing Coastal Erosion” section later reviews the experiences of Middle East and North Africa economies as well as international best-practice examples in coastal management and combating coastal erosion.
Managing coastal development will bring important cross-benefits for coastal issues beyond mitigation of coastal erosion. Coastal zones are major contributors to the continued flow of plastics into the Middle East and North Africa’s seas, together with plastic waste deposited by rivers. Hence, setting up a comprehensive ICZM scheme that includes improved waste management processes (for both solid waste and effluent discharge) will reduce the amount of plastics ending up in marine spaces. Furthermore, clear development plans in such schemes could involve coordinated measures to reduce plastic waste in coastal zones,
whether it has been dumped there or deposited by waves from the open sea. Similarly, setting up a comprehensive development plan is crucial to ensure that coasts are used in the most productive and most sustainable fashion. This, together with the increased protection from coastal erosion, would lead to more efficient use and valorization of these assets while also protecting them for future generations.
Setting in motion sustainable management schemes for coastal development will contribute to greener, more resilient, and more inclusive development (the GRID path) in the Middle East and North Africa. Coastal erosion comes with large adverse effects on human development (that is, built infrastructure) as well as on local ecosystems in the region (as discussed earlier in the chapter). Long-term management of coastal development under the tenets of an ICZM scheme will hence benefit coastal communities and local biodiversity in various ways:
• Limiting uncontrolled development will reduce conflicts among stakeholders and ensure that the gains from using coastal assets will be distributed more justly and sustainably, providing income sources for those depending on intact coasts. • Restoring ecosystems using NBS will not only reduce coastal erosion but also provide habitats for local flora and fauna, greening the region’s coasts.
• Actively involving local communities in such revitalization efforts implies additional income-generating activities for these communities, especially for the poor (given the high labor intensity of such work). • Promoting more environmentally friendly coasts and beaches can maintain tourism while also encouraging development of new ecotourism ventures.
Thus, successfully managing the coasts and mitigating their erosion will contribute to putting Middle East and North Africa’s economies on a GRID path and ensure that these important natural assets remain the boon to future generations that they have been to others for so long.
Better management of coastal-erosion risks will benefit the Middle East and North Africa region. Climate change exacerbates these risks. This section discusses three priorities, based on their effectiveness in combating coastal erosion, their economic and social benefits, and their level of interdependence with other policies and interventions.
No. 1: Understand the Drivers of Coastal Erosion and Improve Access to This Data
Understanding the drivers of coastal erosion is a prerequisite for many interventions. First, identifying and monitoring the erosion hot spots are critical preconditions (as further discussed later in this section). In the selected hot spots, identifying the drivers of coastal erosion is critical to inform the planning for interventions to reduce erosion. Because the local drivers of coastal erosion are site-specific, the most effective and efficient solutions also vary across these sites.
Source-identification analysis includes monitoring and computational modeling of coastal morphology, sediment flows, and fluid mechanics as well as the impact of coastal development. This entails analysis of river flows and the impacts of (a) upstream river-basin development schemes on coastal wetlands, (b) sediment flows on shoreline replenishment processes, and (c) particular activities such as extraction of gravel and sands from rivers and beaches.
Finally, the data and related information must be made publicly available to build public engagement, awareness, and consensus for future policy reforms. Data-based impact analysis is critical for designing solutions for coastal-defense investments and for environmental impact assessments of ICZM plans, including new developments. The transboundary nature of coastal erosion also makes regional cooperation on data and information sharing important to identify drivers of the phenomenon across country borders.
No. 2: Engage Stakeholders in ICZM Planning at All Levels
Multistakeholder participation in ICZM planning at the municipal, national, and regional (subnational and multinational) levels is key for the design of effective solutions for combating coastal erosion. Coastal-zone management requires a holistic approach that includes all stakeholders—for example, port authorities, fishers, hotels, utility service providers, nature conservation specialists, cultural heritage authorities, restaurants, technical specialists, and representatives of local communities (more on this in the “Comprehensive Policies and Actions for Reducing Coastal Erosion” section). Thus, joining forces is an important step to take in parallel with launching the data collection, analysis, and monitoring effort. Doing so across country borders would be an important step to address joint efforts and maximize the effectiveness of ICZM schemes. ICZM also needs to use multistakeholder processes to identify hazardous and ecologically vulnerable areas, areas designated for development, and measures for reducing erosion.
Comprehensive ICZM planning, both spatial and temporal, will help ensure coastal sustainability and combat erosion—all while identifying economic opportunities and supporting efficient coastal development
plans, which differ across coastal areas and shape the site-specific responses to coastal erosion. A comprehensive ICZM plan will help inform policies through not only prospective management and development but also reactive management and control interventions, as discussed in detail in the “Comprehensive Policies and Actions for Reducing Coastal Erosion” section. As mentioned earlier, implementing such an ICZM scheme will also bring cross-benefits by reducing marine-plastic pollution of the seas and coasts. Through the consultation with all relevant stakeholders and consideration of their needs, the introduction of ICZM schemes also directly contributes to more inclusive development in general.
No. 3: Use Nature-Based Solutions on Land and Sea
Nature-based solutions (NBS) can combat coastal erosion and restore coastal and marine ecosystems. Using NBS in the seas, coastal wetlands, and along shorelines can increase coastline resilience by weakening incoming waves and inland winds and by retaining and stabilizing sediments. (For more on these approaches, see the later subsection on soft defenses under “Reactive Management and Control Measures.”)
Increasing vegetation cover through the planting or restoration of (a) seagrass fields within marine ecosystems, mangroves, and other natural vegetation in coastal wetlands and shorelines; and (b) marshes and other flora on coastal dunes will help improve habitats and stabilize sand dunes, beaches, wetlands, and natural coastal protection processes. Restoring coral reefs in the Red Sea and RSA can help combat erosion by diminishing wave energy. Importantly, these efforts should take into account the preexisting natural landscape to avoid disturbing the local flora and fauna. And all these natural interventions require supporting environmental policies.
NBS offer multiple benefits in addition to coastal resilience, including carbon sequestration, biodiversity, and coastal ecosystem restoration. They also can be used for educational purposes and provide lasting benefits to the tourism sector. And, given the labor-intensive nature of these interventions, the environmental benefits are accompanied by economic opportunities. Moreover, relying on the knowledge of the local population regardless of gender or educational background is key for a successful implementation of NBS. Hence, their broader use also contributes directly to longer-term, inclusive economic development through sustainable management of natural resources—very much in line with a GRID framework.
One Must Measure What One Would Manage: The Sources of Coastal Erosion
Before one can effectively manage coastal erosion and ensure the sustainability of the coastline, one must first understand the spatial patterns
(where) of coastal erosion (hot spots) and the reasons why (how) the erosion is occurring. Knowing where and how coastal erosion occurs requires a holistic approach using data, monitoring, and analysis as well as stakeholder engagement to sustainably plan ahead for mitigating the risks of coastal erosion. These elements, as well as the evaluation of potential solutions, are essential before putting the necessary policies into place.
Although the particular sources of coastal erosion along an individual part of the coast are very site-specific, some general drivers are known to cause changes in the coastal landscape, not only in the Middle East and North Africa but globally. This section identifies these general drivers and how they might be affecting coastlines. However, for a specific part of the coast, multiple sources may be acting together to shape the coastal landscape, with specific dynamics and their sources varying across the coastline. It is hence important to account for local characteristics to effectively combat coastal erosion at a specific site, necessitating detailed antecedent analyses.
Furthermore, as this section lays out, human interventions at one site may influence erosive processes at others. Hence, it is also important to consider coastal dynamics (such as sediment transport across local hot spots) in an integrated manner. For the Middle East and North Africa, such detailed studies of flow dynamics along the coast and site-specific sources of coastal erosion are limited, increasing the difficulties of tackling coastal erosion effectively.
Overview of Coastal Erosion Drivers in the Middle East and North Africa
Various factors drive changes in the coastal landscape and coastal erosion—some occurring naturally and others induced by human activities (figure 5.5). Direct anthropogenic drivers include coastal subsidence (due to heavy infrastructure near the coast or aquifer-water extraction), coastal infrastructure (such as ports and marinas), defense developments, and land reclamation. Natural physical forcing elements such as storms, SLR, and currents are exacerbated by human-induced climate change (Sytnik et al. 2018).
Coastal areas with different tidal dynamics and wave-energy incidences demonstrate unique coastal morphologies (Hayes and FitzGerald 2013). Fluvial and alongshore sediment transport are major morphodynamic processes that determine the shape of the coastline (Sytnik et al. 2018) and often determine how the coast is divided into management cells. Human interventions, such as ports or groins, intervene in the hydrodynamic processes along the shoreline. Often, these interventions
