Restore sediment supply to coastal zone

Located southeast of Bayou La Batre, Coffee Island is a barrier island that provides a buffering capacity for shorelines in Mobile County [5]. Since 1950, the shoreline on the island has been eroding. In response, the Nature Conservancy has put in a ‘’living shoreline’’ construction in 2010 to reduce wave energy and decrease erosion the island has been facing [1]. A ‘’living shoreline’’, ‘’refers to the use of nature-based techniques and materials such as oyster shells, reef blocks, bagged shells, live shellfish, and plants to help protect eroding shorelines’’ [2]. While the living shorelines constructed in 2010 still provide habitat benefits, these efforts no longer protect the shoreline from erosion. This in turn threatens not only the island's buffering capacity, but also the integrity of the marsh on the island [5]. Therefore, the Nature Conservancy has secured funding for a second project on the island, the Coffee Island Restoration project (in 2023) that aims to implement a (longer) 5,000-foot living shoreline breakwater, including the use of ‘’super sacks’’ – a specific kind of sediment barriers functioning as dikes – to protect the coastline while enhancing habitat [4, 6]

Fairhope's Municipal Pier is a popular bayfront destination featuring a 1/4-mile pier, swimming areas, picnic spots, a landscaped rose garden, benches, restrooms, a marina, a restaurant, walking trails, and a duck pond. However, the area has been fragilized over the years. The beaches are absent and less prominent now, due in large measure to the presence of shoreline hardening (Ref 5), making the shoreline more vulnerable to climate hazards (Ref 5).
The main goal of the Working Waterfront and Greenspace Restoration Project is to introduce safe and user-friendly improvements to the 10-acre South Beach Park area, which encompasses the Municipal Pier (Ref 2). These upgrades aim to enhance the public's use and access of the waterfront, while ensuring the park's long-term resilience and sustainability (Ref 2). The new design tackles both the structural issues of the bulkhead/seawall and the overall aesthetics of the Fairhope Pier area (Ref 2).
Over the years, storms, particularly Hurricanes Sally and Zeta, have compromised the structural integrity of the anchoring hardware of the bulkhead/seawall, causing parts of the wall to shift. Additionally, water intrusion behind the wall has eroded the soil supporting the walkway in certain areas (Ref 2). Other important features include new handrails, decking, restroom facilities, and lights on the pier. The project will also add new stairs leading to the bluff, restore the fountain, and renovate the parking lot. A funicular lift will be installed at the bluff to enhance accessibility (Ref 5).
Pedestrian safety will be improved to meet the requirements of the Americans with Disabilities Act. Other enhancements include landscaping with new irrigation, and the construction of new sidewalks (Ref 2, Ref 4).

Martinique is a biodiversity hotspot, home to over 1,500 endemic plants, 70% of which are under threat from human activities. In response to these pressures, the Péyi Vert [Green Country] initiative was launched to plant endemic trees and strengthen the island's biodiversity. Beyond simply preserving species, these trees are crucial in maintaining healthy ecosystems, as they provide essential services such as carbon sequestration, shade, food for human consumption, soil decontamination, pollination, and protection against coastline erosion.
Launched in June 2020 by Entreprises et Environnement (EE), a not-for-profit business association representing 80 Martinican companies, the Péyi Vert initiative aims to plant 1 million native trees (either Martinican or Caribbean) over five years. It can be seen as a Martinique-wide strategy to adapt to and mitigate climate change. Péyi Vert facilitates connections between people who want to plant trees and Martinican companies that serve as financial sponsors. The initiative emphasizes conserving natural heritage by planting endangered species, as well as promoting native species that, while not necessarily threatened, provide valuable ecosystem services or contribute to biodiversity restoration.
Between 2020 and 2023, EE reported planting 50,000 trees (Refs 1, 4, 6, 7). Although individuals can make donations, Péyi Vert primarily seeks funding from companies looking to offset their carbon emissions or enhance their Corporate Social Responsibility (CSR). To achieve its goals, the initiative mainly collaborates with municipalities, companies, and farmers (Ref 3).

The ReDuna project, initiated in 2014, focuses on restoring the sand dune ecosystem in Costa da Caparica (Almada) in response to severe coastal erosion exacerbated by sea-level rise and winter storms. It aims to strengthen the resilience of dunes to environmental pressures while restoring ecological balance. Actions include sand nourishment, the installation of willow sand fences, and the planting of 100,000 native species. Community engagement was a key factor, involving local residents, NGOs, and schools in maintenance and replanting efforts. The project has been successful, with significant biodiversity recovery, establishing deep-rooted vegetation, and stabilising the dunes. Ongoing monitoring and adaptive management are central to its strategy, ensuring long-term sustainability. The ReDuna project serves as a replicable model for similar coastal protection initiatives globally (Ref 1).

The project aims to protect seagrass meadows, which are vital habitats for the prey of resident dolphins and essential to the local fishing economy. The initiative involves local fisherwomen, called "Keepers of the Sea," in activities such as marine education, awareness campaigns, and monitoring the health of the seagrass meadows (Ref 1). Founded in 2015, Ocean Alive aligns with several UN Sustainable Development Goals, including ocean conservation, gender equality, quality education, and climate action (Ref 4). The project is supported by partnerships with UNESCO and other organizations, and it extends its efforts to Portuguese-speaking African countries. Ocean Alive’s activities also include advocacy for blue carbon ecosystems and programs that involve community engagement and social innovation (Ref 2, Ref 5).
One of several implementation projects targeted safeguarding the young seagrass meadow at Cambalhão Bay, at the entrance of the Sado estuary, as an Ocean Alive’s initiative in partnership with SeaTrees by Sustainable Surf (Ref. 2). The Cambalhão meadow is made up of 202 patches of seagrass. Unregulated shipping is one of the factors in the degradation of the prairie, and to protect it, Ocean Alive is running a campaign to raise awareness about recreational boating (Ref. 6).

Coastal erosion is a well-known consequence of climate change, driven by rising sea levels, extreme storms, and powerful coastal surges. Dollymount Strand, a popular spot for bathing and water sports in Dublin, is particularly vulnerable. Located on North Bull Island and managed by Dublin City Council, the area is part of several protected zones, including a Special Area of Amenity, a Special Area of Conservation, a Special Protection Area, a Ramsar Wetland, a Natura 2000 site, and the UNESCO Dublin Bay Biosphere. To help mitigate this issue, Dublin City Council has implemented a solution that works with, rather than against, natural processes.
During late summer and autumn—particularly following high tides, warm weather, and storms—a type of seaweed called Ectocarpus siliculosis naturally accumulates along Dublin Bay’s beaches. Instead of removing it, the council allows the seaweed to remain, recognizing its essential role in maintaining the beach’s rich biodiversity. Ectocarpus contributes to the health of the coastal ecosystem, supporting marine life and enhancing the natural resilience of Dublin Bay. (1.2)

The project at Poetto Beach in Cagliari, Italy, implemented by the municipality of Cagliari, began in 2022. It focuses on protecting and restoring the dune system while raising public awareness about the importance of preserving the coastal ecosystem. The project recognizes the delicate balance between environmental preservation and public enjoyment of Poetto Beach.
Key activities include installing barriers and signs to prevent trampling and littering, modifying beach access points to reduce erosion, and implementing significant interventions to restore the beach. These interventions involve strengthening anti-erosion measures with dune confinement and sand retention systems, as well as creating natural barriers (natural repopulation of native plants ) to protect the seashore. Public education initiatives aim to encourage responsible beach use and enhance understanding of the dunes' fragility. Additionally, new access walkways will be installed, and existing ones will be improved, including the creation of four wheelchair-accessible pathways to the water, designed for easy entry.
This comprehensive plan for protecting and enhancing Poetto's environmental resources is valued at €945,000 and is funded by the European Regional Development Fund.
Overall, the goal is to enhance environmental quality, promote sustainable beach use, and prevent both natural and economic losses. By balancing enjoyment of Poetto's natural resources with their protection, the project aims to ensure the long-term preservation of this valuable coastal area (Ref. 1, 2 & 4).

Salines Beach, a popular destination for over a million visitors annually (Ref 9), is facing severe erosion due to rising sea levels and poor coastal management. Since 1995, the beach has lost more than 20 meters in width. This loss has been worsened by vehicle traffic and the introduction of coconut trees in the 1950s, which reduced the native root systems that once helped to stabilize the coast (Ref 5). Now, the encroaching sea threatens to swallow the road that runs along the beach.
In response, the Salines Conservation Committee—comprised of concerned community members and environmental groups—has been advocating for urgent action to halt the erosion. They have called for a renaturalization of the area through the replanting of endemic species and restrictions on car traffic, both aimed at restoring the beach’s natural resilience.
When part of the road collapsed in July 2022, the committee took immediate action, organizing community-based interventions. These efforts included blocking traffic, raising public awareness, and planting over 60 endemic plants in the damaged area. The aim was to reestablish a root network capable of anchoring the coastline and capturing shifting sands (Ref 1; 2). The intervention was described as "a response to the urgent need to rebuild the root network, an ecological engineering solution recognized as the most effective method for retaining beach sand and slowing coastal erosion" (Ref 2; 1). The intervention on this section of the coast was first completed, then discarded by the municipality of Sainte-Anne (Ref 2). Regional and National agencies are currently undertaking the restoration works but it is unclear the stage of completion (See Ref 3).

The Mobile Bay National Estuary Program is one of 28 National Estuary Programs established by the United States Environmental Protection Agency, focused on safeguarding and restoring the water quality and ecological health of nationally significant estuaries (Ref 2). One of the four main areas of work of the project (Ref 2) is focused on Ecosystem Restoration and Protection (ERP), aiming at restoring and protecting ecosystem function and services (Ref 4). One of the projects implemented in 2023-2024 in the ERP category is the Deer River Coastal Marsh Stabilization and Restoration project, aiming at restoring and protecting the saltwater marshes of the area (Ref 8).
The issues faced in the Deer River Shoreline are shoreline recession, marsh deterioration, and loss of natural function from erosion, apparently caused by heavy storms, tidal impacts, and wakes from cargo ships entering or exiting the Theodore Ship Channel (Ref 8). Indeed, the saltwater marshes of this area have started to erode at a rapid rate, up to 12 feet per year (Ref 7).
The project aims to enhance the natural function of ecosystem services to improve the area's resilience. It will restore the eroded marsh by creating offshore structures to protect the shoreline and attenuate the waves. The project also aims to restore the water quality of the Deer River by dredging it out, thus improving the water flow. The material dredged out will be used to nourish the marsh (Ref 9).

Trade winds from the east over the Bay of Fort-de-France increase agitation at the "Étang Z’Abricots" marina, reducing user comfort and raising maintenance costs for port equipment and vessels. Climate change worsen these problems, increasing the risks of coastline erosion, extreme weather events, and rising sea levels, which may diminish the protective effect of "Pointe des Sables," leaving the marina more exposed to the winds (Ref 1; 2).

The Z’AB project aims to address these challenges by creating a protective barrier for the port by using mangroves. This involves installing lightweight, reversible devices to elevate the sea floor and accumulate sediments, encouraging the natural colonization of mangroves south of Pointe des Sables. Natural colonization refers to the growth of mangroves through processes like seed dispersal and sediment buildup. Once established, the mangrove will act as a natural buffer, protecting the marina from rough seas and adapting to rising sea levels. The project also includes educational efforts to raise awareness about the importance of mangroves for the region’s environmental issues and biodiversity (Ref 1).

Although the Z’AB project has been in planning since 2018, in 2021, a separate project to extend the marina, costing 7 million euros, was approved by the water park authorities (Ref 5). The extension will add 77 new vessel spaces (Ref 7), but it threatens portions of the mangrove and a strictly protected coral species, Oculina Diffusa, found in the area (Ref 6, p.17). While the marina extension project aims to offset the loss of coral and mangrove with various solutions, "Projet Z'AB" is not explicitly mentioned as a compensation mechanism (Ref 6, p.24). However, stakeholders involved in Projet Z'AB are also participating in the development of the marina extension (Ref 6). It remains unclear to what extent Projet Z'AB will be used to mitigate the environmental impact of the extension.