Coastal ecosystems restoration and maintenance (mangroves, dunes, saltplains, underwater meadows)

The D'Olive Creek Restoration project is designed to address the significant environmental challenges facing the D’Olive Creek Watershed and its tributaries (Tiawasee and Joe’s Branch), primarily caused by increased urbanization. Over the last several decades, the area has experienced severe erosion, sedimentation, and habitat degradation due to stormwater runoff from new residential and commercial developments. This runoff has led to stream channel instability, loss of wetlands, and impaired water quality in both D'Olive Creek and Mobile Bay, threatening aquatic and wildlife habitats (Ref 2).
The project involves restoring degraded streams and implementing management measures to reduce the downstream impacts within the watershed. Key activities include stormwater retrofits, stream restorations, and continuous monitoring. These efforts aim to stabilize stream segments and significantly reduce sediment loading into the northeast quadrant of Mobile Bay. This is crucial for improving water quality and clarity, which is necessary for re-establishing submerged aquatic vegetation (SAV) beds that serve as critical nursery areas for shellfish and finfish (Ref 1). By using natural materials like rock and living plants, the project also seeks to create a sustainable and ecologically balanced watershed system (Ref 3).
The anticipated outcomes include enhanced water quality in D'Olive Creek and Mobile Bay, reduced erosion and sedimentation, and the restoration of vital habitats, which will contribute to the region's overall ecological health (Ref 1, 3). This restoration project is part of a broader strategy outlined in the 2002 Comprehensive Conservation Management Plan for the Mobile Bay Estuary (Ref 1).

The Ciénaga de las Quintas is a coastal wetland located alongside one of Cartagena’s main roads, adjacent to the public market square and situated between the Jiménez and Bazurto Bridges. It is home to two predominant mangrove species (Ref 1). The wetland currently faces pollution problems because it is used for the disposal of solid waste, such as plastics and construction materials, and it receives wastewater and household garbage from nearby residences. Las Quintas is also the main waste disposal area for the Bazurto market, which handles 43,430 tons of food products each month (ref 3). The recovery initiatives for the Ciénaga de las Quintas are led by the Environmental Public Establishment of Cartagena (EPA Cartagena) in collaboration with other public institutions, the private sector, and citizens, with the main goal of achieving the ecological restoration of the city's water bodies and to maintain and preserve our mangrove ecosystems (ref 2). Since 2020, key implementation activities have included the removal of solid waste, planting of native tree species, dismantling of informal structures within the mangrove zone, and the rehabilitation of areas previously occupied by debris (Refs 4, 5).

Cagliari's waterfront is currently characterized by extensive soil sealing, which has rendered the soil impermeable, leading to a loss of biodiversity and contributing to the urban heat island effect. Additionally, the waterfront is disconnected from the city due to heavy traffic. In 2023, the Municipality of Cagliari launched the "Green Promenade for Cagliari’s Seafront" project, aimed at revitalizing the waterfront and reconnecting the city with its coastal heritage. Led by Stefano Boeri Architetti, the project seeks to transform the area into a continuous green space that integrates pedestrian pathways with shaded public areas, functioning as a "green lung" to mitigate urban heat and enhance biodiversity.
The initiative will introduce over 200 new trees and 5,700 square meters of green space, creating a park that beautifies the area, improves air quality, and lowers local temperatures. A key focus of the project is fostering cultural and social inclusion by developing new community hubs that encourage diverse activities and strengthen social cohesion. Additional features include recreational areas, sports fields, and outdoor seating. (Ref. 1, 2,3)
The project also aims to enhance social inclusion, environmental sustainability, and urban connectivity, ultimately transforming the waterfront into a vibrant public space that reflects Cagliari’s identity.
However, the lengthy construction process has disrupted local businesses and reduced foot traffic, making the area less attractive during the redevelopment phase. (Refs. 10, 11, 12 & 13).

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 Martinican Marine Natural Park (MMNP) was established in 2018 to protect key marine habitats, including coral reefs, mangroves, seagrass beds, and open waters. These areas are home to important species like sea turtles, dolphins, and tropical fish. The park’s conservation efforts focus on addressing threats from human activities such as pollution and overfishing. It also collaborates with ocean-related industries, such as tourism and fishing, by recommending, funding, or conducting research aimed at promoting more sustainable practices within the MMNP.

To support its work, the park operates a growing fleet of boats that raise public awareness, resolve conflicts, and enforce the protection of designated areas. The MMNP spans an area of 47,340 km², extending from Martinique's coast to the boundary of the French Exclusive Economic Zone. The park's management board, which includes diverse stakeholders, must be consulted for advice on development activities that impact the marine environment. Their goal is to balance competing interests within the region.

The park receives funding from the French Office for Biodiversity (OBF) to carry out initiatives that protect the marine environment, promote sustainability, and raise public awareness. Notable efforts include creating or restoring habitats for species such as sea turtles and sea urchins, managing invasive species like sargassum algae, restoring coral reefs, and training resource users such as whale-watching companies and diving clubs. Other initiatives include reducing plastic pollution through clean-ups, supporting sustainable fishing practices (e.g., artisanal coastal fishing), installing eco-friendly moorings, funding Marine Educational Areas (MEAs), and sponsoring cultural events that promote marine conservation (Ref 1; 2; 3).

The Juan Angola River is an urban channel included in the system of rivers and channels of Cartagena, and it connects the Ciénaga de la Virgen wetland and the Bay of Cartagena, facing similar issues as the Cienaga de la Virgen such as illegal occupation of its shores, illegal waste dumping, deforestation of mangroves, and pollution. The recovery plan for the Juan Angola River is led by the EPA Cartagena (Environmental Protection Agency), with the support of other institutions, aiming to restore the Juan Angola’s ecosystem. This includes targeting the mangrove forest, dredging the natural channel, and delineating buffer zones with urban infrastructure to create public recreational spaces. The activities involve relocating people illegalling cupping informal settlements from the river shore, moving an existing bridge (the Benjamín Herrera bridge) which obstructs the current, recovering the low tide and riverbed areas, building pedestrian paths, clean the riverbank, recover mangrove areas and establish programs of education and environmental awareness (ref 1 and 2).

Del Nervi Park is a project co-led by the Port System Authority of the Sardinian Sea and the Municipality of Cagliari. Completed in 2021, it transformed a long-abandoned and degraded area on the Cagliari waterfront into a vibrant green space. The two-hectare site surrounds a 1950s industrial building and underwent extensive redevelopment to enhance its structural integrity and convert it into a public park. With a budget exceeding 5 million euros, the project prioritized green investments by creating new pedestrian and cycling paths, along with green spaces featuring local plants, flower beds, grass, and lawns.

Nervi Park is set to become a key destination for leisure, sports, and cultural activities, while also providing the Cagliari community with greater access to green spaces. The environmental and urban renewal efforts aimed to beautify and modernize the area, with future development plans focusing on long-term management and the introduction of commercial activities to further enhance the space
The project faced significant barriers, including prolonged disruptions due to the COVID-19 pandemic, which halted work for about eight months. (Refs. 1, 2, 3 & 4).

The Ciénaga de la Virgen is a coastal wetland (cienaga) located on the north side of the border of the city of Cartagena, separated from the sea by La Boquilla's sandy beach. It has a maximum width of 4.5 km, a length of approximately 7 km, a water body area of about 22.5 km², and depths of up to 1.6 m. It is connected to the city's canal system (ref 1). The recovery project of la Cienaga de la Virgen, led by EPA Cartagena, is proposed as a strategy to address the issues affecting the water body, local communities, the economic activities that depend on it, and the ecosystems that regulate the water cycle and provide multiple services, many of them essential, with an integrated and global management approach based on the basin as the unit for planning and resource management (ref 14). Some of the main problems of the wetland are related to illegal settlements on its shore, as well as illicit dumping of waste, pollution by wastewater from the illegal settlements and deforestation of mangroves (ref 4). Key activities include stopping illegal occupation by relocating established families, improving roads, promoting reforestation, encouraging social participation, managing wastewater, and enhancing tidal systems (ref. 1 and 15).
Alonside the EPA, other stakeholders involved include the regional authority "Regional Autonomous Corporation of the Canal del Dique" (Cardique), with jurisdiction in the rural area, and Cartagena Mayor's Office, and the local community, involved in all the stages of the plan thanks to the “mesas de governance” or "governance tables", discussion spaces where different actors participate in the decision-making (ref 2).

The mangrove area of Morne Cabri, located in the municipality of Le Lamentin and sharing the bay of Fort-deFrance, is the largest mangrove area in Martinique. Since 2011, the municipality has led efforts to understand and better manage the area (Ref 1). The natural regeneration of the mangrove is threatened by fresh water run-off (from waste and rainwater), invasive species and pollution. However, it is an important protection against extreme weather events, operates as a carbon sink for the island and provides recreational activities (Ref 1). The municipality has led several initiatives supported by volunteers, local businesses, national subsidies and private donations (See: Ref 2, 3, 4, 11).

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).