Water management (SDG 6)

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 Gårda pilot rain garden has been constructed as part of the research project Innovative Rain Gardens at Chalmers University of Technology in Gothenburg. In addition to causing flooding, runoff rain water in urban environments can be contaminated with microplastics, organic pollutants and metals which can spread into the natural environment. Yet, most of the storm water in urban environments is not treated. The purpose of the Innovative Rain Gardens project is to research the ability of a pilot rain garden to treat such pollution. The project acknowledges the function of a rain garden to prevent flooding, but in this study only the pollution treatment potential is investigated. The pilot rain garden was constructed next to the E6 highway in central Gothenburg [Ref. 1-4]. It includes several different bioretention filters where selected plants are grown in filters containing different materials such as biochar, ash and soil [Ref. 2, 3]. Results so far show that the use of rain gardens can significantly reduce pollution. However, further research is needed to determine the long term function of the bioretention filters and the potential of scaling up the NBS. The project is funded by the Swedish Research Council for Sustainable Development (Formas), IMMERSE - Implementing Measures for Sustainable Estuaries, an Interreg project supported by the North Sea Programme of the European Regional Development Fund of the European Union, and COWIfonden (private foundation) [Ref. 1-3].

Sourced from Northern Worcestershire, the River Stour has played a significant role in the industrial heritage of Birmingham and the Black Country (Ref 1). It consists of 11 Water Framework Directive water bodies and multiple tributaries, spanning 200 km in length (Ref 2, 3). Once a pristine Salmonid river that powered the Industrial Revolution, rapid industrialization severely impacted the river, leaving it heavily polluted with sewage (ibid.).
Initiated by the Birmingham and Black Country Wildlife Trust (BBCWT) in 2021, the Love Your River Stour (LYRS) project focuses on Dudley and Wolverhampton, aiming to transform the River Stour and its surrounding green spaces into a beautiful, wildlife-rich source of pride for local communities and to create a corridor for wildlife to thrive through the heart of the Black Country (Ref 4).
Phase 1 of the project was completed in June 2023, bringing significant improvements along the river (Ref 5, 6, 7, 8). In Phase 2, the project will extend to a stretch running through Cradley Heath and Lye (Ref 7, 8). This initiative is funded by the UK Government's Green Recovery Challenge Fund.

Civic Space Park, located in the heart of Phoenix, Arizona, is a notable example of urban design aimed at addressing the region’s increasing urban heat. In Phoenix, rising temperatures affect health, safety, comfort, and economic growth, and this impact is expected to worsen over time. In response, the park was developed to transform an underused site into a vibrant public space that prioritizes community engagement, sustainability, and urban revitalization.
The project was realized through a public-private partnership between the City of Phoenix and Arizona State University, with strong community involvement shaping its development. This collaboration led to the “Urban Weave” concept, a design that embodies the identity and values of the local community.
Civic Space Park was designed with several goals in mind. Increasing the tree canopy was essential to help reduce the urban heat island effect and improve air quality. Creating a welcoming area for social interaction, recreation, and relaxation was equally important to enhance community well-being. Water conservation was also prioritized, achieved through innovative stormwater management techniques such as permeable paving and underground infiltration. The park incorporates renewable energy generation as well, with on-site solar power helping to reduce energy consumption.
One of the park’s unique features is its extensive use of pervious concrete paving, designed to allow stormwater to permeate directly into the subsurface. However, during installation, it became clear that placing the material over highly compacted soil limited water infiltration. To improve its effectiveness, future designs could include a plastic vapor barrier beneath the permeable paving to capture water and direct it to planting beds. This adjustment would enable the paving to act as a collection and storage system, gradually releasing water into the surrounding vegetation.
(1-6)

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).

The Tres Rios Ecosystem Restoration Project is an ambitious initiative aimed at revitalizing a seven-mile stretch of the Salt and Gila Rivers in Phoenix, Arizona. The Tres Rios Environmental Restoration project involves the rehabilitation of nearly 700 acres in and around the Salt River, restoring a vital wetland and riparian habitat. Initially conceived in 1993 to tackle water quality issues and improve flood control, the project gained significant traction in the 2000s through a partnership between the City of Phoenix and the U.S. Army Corps of Engineers (USACE). Funding was structured with 65 percent from the USACE and 35 percent from the City of Phoenix and the Sub-Regional Operating Group Members, including Scottsdale, Tempe, Glendale, and Mesa.
The Tres Rios project encompasses habitat restoration, flood control, and recreational development, with the primary objectives being to restore a degraded ecosystem, enhance water quality, and provide new recreational spaces. Construction involved relocating 1.6 million cubic yards of earth to shape three large wetland zones and two deep-water retention basins. Additionally, 18,000 feet of underground water lines and 600 feet of 84-inch fiberglass effluent pipelines were installed. To establish a thriving wetland habitat, the project coordinated the planting of over 300,000 aquatic and terrestrial plants.
Habitat restoration efforts re-establish native vegetation and create wetland areas that support local biodiversity. The lush and scenic Tres Rios is now home to more than 150 different species of birds and animals like muskrats, raccoons, skunks, coyotes, bobcats, and beavers. By using treated wastewater to sustain the ecosystem, the project reduces dependency on natural water sources, thereby helping to mitigate water scarcity. The Tres Rios Ecosystem Restoration Project serves as a model for sustainable urban ecological initiatives, combining environmental health with community benefits. (1-8, 10-13)

The Heat Action Planning project in the Lindo Park-Roesley Park Neighborhood in Phoenix, Arizona, specifically addresses the heat-related challenges residents face in this area. Phoenix is particularly vulnerable to extreme heat events, and this project aims to provide both mitigation and adaptation strategies to reduce the direct impacts of heat and help residents cope more effectively with these conditions. As part of the city’s broader Heat Action Plan, the Lindo Park-Roesley Park initiative is one of three target areas, including Edison-Eastlake, just east of downtown Phoenix, and the Water Tower Improvement District in the City of Mesa. The project focuses on heat hazards such as extreme temperature events and the urban heat island effect, which disproportionately affect vulnerable populations.
This project is a collaborative effort, uniting a range of stakeholders including The Nature Conservancy, Maricopa County Department of Public Health, the Central Arizona Conservation Alliance, the Urban Resilience to Extremes Sustainability Research Network, Arizona State University’s Urban Climate Research Center, and the local residents. Together, these partners are working to develop comprehensive heat mitigation and adaptation strategies that address social equity and strengthen community engagement. Furthermore, the Heat Action Planning process was designed to serve as a model for future heat resilience efforts and create a local, contextual, and culturally appropriate vision of a safer, healthier future. The iterative planning and engagement method used by the project team strengthened relationships within and between
neighborhoods, community-based organizations, decision-makers, and the core team, and it combined storytelling wisdom and scientific evidence to better understand current and future challenges residents face during extreme heat events.The ultimate aim is to foster a more resilient and equitable neighborhood (1-7).

Lafayette Greens is a transformative urban green space and community garden located in downtown Detroit, occupying a parcel of 1720 sqm that once housed the historic Lafayette Building. Following the building's demolition in 2010, the site, situated near Compuware headquarters and the Detroit Federal Building, was re-imagined through a public-private partnership into a productive urban garden (Ref.1, 6). The garden was designed in 2012 for a local software company, Compuware, which after completion gifted it to a local NGO, The Greening of Detroit, in 2014. Lafayette Greens serves as a green oasis in a bustling urban environment, offering city workers, residents, and visitors a space to relax and engage with nature. The garden produces chemical-free fruits, vegetables, herbs, and flowers, and since 2019, has focused on cultivating a certified pollinator habitat, essential for supporting urban biodiversity. The garden also provides educational programming, including classes on pollinators like bees and birds, and the DIG - Detroiters in the Garden series, in collaboration with Fort Street Presbyterian Church’s Open Door program, fostering community involvement and environmental stewardship. (Ref.2)

The Dublin Urban Rivers LIFE (DURL) project incorporates two interconnected wetlands in Griffeen Park as part of its broader initiative to improve water quality, natural water management and aquatic biodiversity in urban areas. These wetlands were specifically designed as a natural sewage system to treat wastewater from the surrounding areas, addressing a significant environmental issue known as "domestic misconnection." Domestic misconnection occurs when household appliances, such as washing machines, dishwashers, and kitchen sinks, are incorrectly linked to surface water drains rather than the sewage system. This leads to untreated wastewater being directly discharged into local waterways, contributing to contamination.
In the River Griffeen catchment, which includes approximately 12,000 dwellings and associated infrastructure, domestic misconnections are a considerable threat to water quality. The DURL project focuses on identifying and rectifying these misconnected appliances to ensure that wastewater is properly treated before entering the river. This process will not only improve water quality but will also provide flood alleviation and support healthier aquatic ecosystems in the area.
The project is aligned with broader environmental policies, including the River Basin Management Plan 2022-2027, the Water Framework Directive, the Climate Change Action Plan, the Floods Directive, and the draft Biodiversity Plan. One of the key strategies is to use a Geographic Information System (GIS) to streamline inspections for domestic misconnections, making the process faster and more cost-effective.
The constructed wetlands in Griffeen Park, with a standing water depth of approximately 30 cm, are planted with a variety of native Irish species. These wetlands offer a natural, sustainable solution to wastewater treatment, with the potential for similar applications across Europe. (Ref. 2, 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).