Environmental regulation

The City of Mobile has developed and implemented a Storm Water Management Program (SWMP) as required by the regulations of the Environmental Protection Agency (Ref 1). Flooding is a significant issue in Mobile, occurring frequently throughout the town (Ref 3). The SWMP aims to protect water quality and prevent harmful pollutants in stormwater runoff from entering the Municipal Separate Storm Sewer System (MS4) area (Ref 1). Stormwater runoff refers to rainfall that does not seep into the ground but instead flows over yards, streets, parking lots, and buildings, eventually entering the storm sewer system, which directs it into creeks, rivers, bays, and the Gulf of Mexico (Ref 1). Stormwater can collect pollutants such as trash, debris, sediment, heavy metals, oils, and hazardous household materials. Additionally, development increases impervious surfaces, leading to more stormwater runoff (Ref 2).

The riparian forest of Montgérald, through which the “Monsieur” River flows, is located within Fort-de-France and boasts rich biodiversity, featuring around 100 species of shrubs and trees and about 30 animal species, including 16 types of birds. It is one of the last remnants of the mesophilic forest type and the only example in a French peri-urban setting. This unique ecosystem is recognized as a Natural Area of Ecological, Faunal, and Floral Interest (ZNIEFF) and a Classified Wooded Area (EBC), underscoring the need for conservation efforts.
Covering nearly 21 hectares, this site offers ecological benefits like air quality improvement and temperature regulation, providing a "fresh air island" near the city center. However, it faces significant challenges, including flooding caused by climate change and heavy rains, which exacerbate erosion along the Monsieur River. The area is also threatened by invasive alien species, making conservation measures even more crucial.
Since 2015, the municipality of Fort-de-France, along with project partners, has been working on developing this natural space for both conservation and public engagement purposes. The most recent actions occurred in 2020, including riverbank restoration, clearing invasive species, and creating walking paths and educational installations. Additionally, the project features an awareness campaign targeting local schools. The ongoing initiative aims to merge biodiversity conservation with community recreational use and environmental education, ensuring the resilience of this vital ecosystem against the impacts of climate change. (Refs. 1, 2, 3)

Alexandria is a city with a special charm, known for its beaches and gardens that act as the lungs through which the city breathes, and are considered a haven for its people (1). Unfortunately, in the last ten years, there has been a decrease in green space due to urban expansion and the establishment of Commercial and profitable projects (1). To address the lack of green space in the city, The Governor of Alexandria has stressed the continued efforts to develop, beautify and plant the squares and turn them into attractive civilized facades, as part of Egypts 2030 vision which aims to move towards a greener city and reduce the effects of climate change. (2). To encourage redevelopment of public green spaces, The Governor launched the “Alexandria shines with its squares” competition in 2023, where the top three neighborhoods with the best redeveloped squares would receive a prize of up to EGP 50,000 [928.45 EUR] (6). The First Al Montazah neighborhood participated in the competition by redeveloping Sidi Bishr Mosque Square (2-5). The 700 meter square was completely upgraded with solar energy, a new irrigation system to conserve water, modifications to the sewer network, and planting the garden with plants that suit the environment (3). The greening activities included planting 400 sticks of various crops in the upgraded square (4).

The Panke is a watercourse that rises outside Berlin and reaches the urban area of the city, flows through the districts of Pankow and Mitte and flows into the Berlin-Spandau Ship Canal in Wedding. The length of the Panke is around 29 kilometres. Almost the entire length of the Panke in Berlin (around 17.6 km) is to be renaturalised - on the section from the state border in the north of Berlin to its confluence with the Berlin-Spandauer-Schifffahrtskanal (BSSK). The Panke is currently a small watercourse that has been heavily remodelled by humans. In large parts of the watercourse, the banks have been straightened like a canal and reinforced with sheet piling, among other things. Existing riverbed drops and weirs prevent fish from travelling unhindered through the watercourse. Studies on water body (structural) quality, typification and other biological quality characteristics have shown that the Panke has poor status values in the majority of Berlin's sections, e.g. in terms of the fish population. The negative assessment results are primarily attributed to the lack of habitat and structural diversity, the lack of passability of the watercourse and, in some cases, high nutrient loads. (Ref. 1)

The restoration of the river was initiated by the State Berlin, following the European Water Framework Directive. The central aim is to implement flood plains and recreate the pre-straightened water course, to ensure space for flooding, habitats for more diverse flora and fauna, increase water flow for better water quality and create a site for recreation in a densely built city. (Ref. 1; Ref. 2) The project started back in 2003 and is expected to be finished in the 2030s (Ref. 2; Ref. 7).

A new landscape plan for the Santry River, developed since 2019, envisions it as “the backbone of a green infrastructure project,” designed to support nature, pedestrians, and cyclists. The project will create a continuous route from the Dublin Bay Biosphere at St Anne’s Park to the wider hinterlands of Dublin at Sillogue.
The plan proposes transforming the Santry River into an “integrated green-blue landscape for ecology and recreation,” incorporating a variety of sports, cultural, and leisure activities. Through an agreement with Fingal County Council and the National Transport Authority, Dublin City Council has commissioned studies to address the existing flood risks along the river.
The council’s goals for the Santry River include river restoration, flood mitigation, greenway development, and environmental protection, extending from the river’s origin in Harristown within Fingal County to its outlet at James Larkin Road. The project framework will span four years, with annual reviews and budget assessments.
The project team has engaged the public in early autumn of 2022 to gather input on these plans, as the Santry River project aims to create a vibrant River Park that integrates natural and recreational elements. Running through North Dublin, this new green-blue infrastructure will serve both ecological and community needs, offering opportunities for sports, culture, and relaxation. Ultimately, it will form a natural corridor linking the Dublin Bay Biosphere at St Anne’s Park with Sillogue, promoting biodiversity while enhancing accessibility for pedestrians and cyclists (2).

In 2001, the local municipality of La Paz, in collaboration with the International Union of Architects (UIA), launched a design contest to create a central park within a protected natural area (3). The park's aim was to develop urban infrastructure while connecting nature with the city (3). The winning architectural design envisioned an infrastructure that would harmonize with the existing natural surroundings and minimize interference with the environment (4).
The park's implementation included pedestrian and bike pathways, numerous panoramic viewpoints, facilities for exercise and cultural events, buildings dedicated to science, historically significant monuments, playgrounds, and the rehabilitation and creation of multiple green spaces (1 & 4 to 6).
While most of the project was completed by 2009, the area's exposure to recurrent landslides, droughts, and illegal waste disposal, combined with ongoing degradation, has necessitated afforestation efforts and maintenance actions from the municipality to ensure the protection of the natural area and enhance its benefits (7 & 8). Recently, the park has been part of a national citizen monitoring program for species, which has improved the categorization of wildlife in the area (11 & 12). Additionally, 2,000 trees were planted in the park in 2023 as part of a reforestation campaign, and cleaning and watering maintenance work has been carried out to support their growth (7 & 13). This initiative is part of a larger project to revitalize the park (10 & 13).
Overall, the park aims to protect local wildlife and plant species while acting as a "green lung" for the city, regulating the climate, providing recreational spaces, and improving livability (14).

The Park am Gleisdreieck is a public urban park in the city centre of Berlin, spanning more than 30 hectares across three individual sites (Ostpark, Westpark, Flaschenhalspark) on former railway tracks. The landscape of the Park am Gleisdreieck is characterised by the central, extensive lawn and meadow areas, which are bordered by woodland-like areas - the so-called track wilderness - as well as various park trees and crossed by wide paths or old railway tracks. The park space features various recreational activities for sports and play as well as community gardens for intercultural exchange (Ref. 12). Being abandoned after WW II, the land rewilded and after being partially opened to the public in 2011, the primary aim of the maintenance and development measures was to harmonise the interests of nature conservation and recreational use. (Ref. 1; Ref. 3)
Many of the plant species in the Park am Gleisdreieck once travelled a long way by train. This is what makes the biodiversity in the park so special. It is a wild mixture of long-established Berlin plants and exotic species that specialise in dry, nutrient-poor soils. The park is part of Berlin's open space network, which extends from Tiergarten to Schöneberger Südgelände. It therefore makes a significant contribution to connecting habitats. (Ref. 1)
Initiatives of citizens have been working for years for the realisation of a park on the former railroad site at Gleisdreick, and so the residents have been involved in the park planning and design in an intensive dialogue process from the beginning and are still involved in the park management. (Ref. 2) The opening of the park served as a compensation measure for the construction of the urban development projects at Potsdamer Platz and aimed at increasing accessible green space in a densely and rapidly built urban environment. (Ref. 4)

The Metropolitan Linear Park is a project initiated by the national government of Bolivia, funded by the Inter-American Development Bank (IDB) (1-8). The proposed park will be located along a disused railway corridor between the cities of La Paz and El Alto, spanning 18.2 km (8, p. 8). The project involves the construction of a linear park, divided into five sections, each with distinct objectives, uses, and designs (8, p. 9). This large-scale initiative aims to improve access to public spaces in La Paz and El Alto, enhance connectivity between the two cities, protect surrounding biodiversity and natural spaces, and strengthen resilience to and mitigate the effects of climate change (3 & 8, pp. 11-12).
To achieve these goals, the project design includes outdoor sports and recreational facilities, pedestrian and cycling circuits, as well as the restoration of parks, squares, and public spaces adjacent to the park corridor (8, p. 9). Some features include balcony corridors, flower and food-producing urban gardens, and viewpoints (5). The project also plans for the re-vegetation of the area with native species and aims to stop the environmental degradation of surrounding natural environments, such as the Pura Pura forest, which has been suffering from ongoing deforestation and waste dumping (8, p. 9). These efforts are expected to increase and support biodiversity in the area (7 & 8, p. 12).
Additionally, the project emphasizes social inclusion, with policies designed to incorporate women, indigenous populations, and persons with disabilities (8, pp. 7-8). The park is intended to raise awareness about climate change and biodiversity, ultimately improving the quality of life and health of nearby residents and the citizens of La Paz and El Alto (8, p. 13).

The Pantanos de Villa Wildlife Refuge is a natural oasis in the heart of Lima. It is considered a marsh of international Ramsar importance, as it is home to a large number of species of flora and fauna. It includes 5 bodies of water with about 210 species of birds, 13 species of fish, and 5 species of amphibians and reptiles, among others (1). It was created in 2006, by Supreme Decree N°055-2006-AG, which established the definitive category for the Pantanos de Villa, under the name of The Pantanos de Villa Wildlife Refuge (2). This protected area was established over an area of 263.27 ha, and its main goal is to conserve a representative sample of the Marshes of the Subtropical Pacific Desert, including important plant communities, as well as migratory and resident avifauna, focusing mainly on species with some degree of threat (1, 2, 6).
In 2016, a Master Plan was approved aimed at strengthening the conservation of the biological diversity of this coastal marsh and ensuring conditions to promote inter-institutional cooperation and participatory management, including neighbours, authorities, municipalities and interested institutions (2).
This Master Plan establishes environmental, economic and cultural indicators defined to be met over 5 years. These are focused on protecting water resources, conserving migratory and resident bird species, ensuring the conservation of the cattail, promoting tourism and recreational activities, fostering environmental awareness activities and engaging citizens in the management of the Refuge (2)
This plan seeks to confront a series of threats that endanger the conservation of this ecosystem. Among the main problems are the illegal extraction of natural resources, such as cattail; the improper use of the space for activities such as bonfires, consumption of illicit substances and pet walks; the change in land use due to urban expansion; pollution from effluent discharges and solid waste disposal; and illegal fishing (2)

The 28th of October Street (28ης Οκτωβρίου) was one of the most neglected streets on the eastern side of Thessaloniki, completely devoid of trees despite its central importance. Additionally, the street suffered from severe flooding during heavy rainfall. In 2011, the Municipality of Thessaloniki, in collaboration with Konstantinos Zervas, the Deputy Mayor for the Environment, Quality of Life, and Free Space, proposed a redevelopment project aimed at transforming the street through the planting of trees and the installation of flower beds that would function as rain gardens (Refs 3, 5). This initiative was part of the "Integrated Green Cities" action, which falls under the European territorial cooperation program Greece-Bulgaria 2007-2013 (Refs 1, 2, 3, 6).

To achieve the dual goals of sustainable rainwater management and urban beautification, decorative trees were planted in specially constructed bioretention tree stands. These stands, along with the flower beds, were designed to collect rainwater, which would then be used to irrigate the trees along the road and the plants forming the rain gardens. Rainwater was gathered from the road surface, pavements, and the gutters of apartment buildings through these bioretention systems (Refs 1, 2). This sustainable water management solution significantly reduced rainwater runoff, improved water quality, and enhanced the area’s aesthetic appeal (Refs 2, 6, 7).