Regional government

The Institute of Physics at Humboldt University of Berlin is an outstanding example of ecological urban development and a global pilot project integrating rainwater management with building cooling through greening. A key feature is the cooling system, which relies on air circulation processes supported by green roofs, facades, and an artificial wetland/pond incorporated into the building's exterior and courtyard.
Rainwater is collected in cisterns and used to irrigate the green façade, enabling evaporative cooling in air conditioning systems. Excess water is either evaporated in the inner courtyard through a pond or allowed to seep away. (Ref. 1; Ref. 4) The greening of the façade is directly linked to energy optimization. During summer, the green façade provides solar shading against extreme heat, while in winter, sunlight passes unobstructed through the glass façade. Additionally, evaporative cooling improves the microclimate inside the building and its surroundings. (Ref. 3)
Berlin, as a densely built city, faces challenges like urban heat and high energy demands for cooling. This project offers a research-driven solution. Monitoring measures water usage for various plants, evaluates evaporative cooling effects, and assesses impacts on the building's energy balance and overall economic and ecological performance. The findings aim to create a foundation for the long-term implementation of innovative, cost-effective technologies. This process is conducted by multiple regional universities. (Ref. 1)
The project was initiated and financed by the state of Berlin and implemented after the building's construction. (Ref. 4; Ref. 5) It serves as a benchmark for sustainable urban development and a research model for similar initiatives worldwide.

The project ‘Planting the Future and Cultivating Life’ aims to create an ecological corridor in the city by reforesting an area of 28 hectares, under the direction of the Porto Velho City Council. It encourages citizen participation in tree planting activities or the management of green areas. To this end, the municipality is carrying out tree planting programmes in parks, squares and along public roads, encouraging citizens to get involved in this endeavour by actively participating in tree planting actions, caring for trees already on their property or raising awareness of the importance of these actions. (1) They seek to involve organisations such as schools, colleges, companies, associations and public organisations to increase the community's and young people's interest in responsible practices and positive attitudes to value and preserve the environment (1).
To achieve this goal, the Porto Velho city council organised a tree-planting day on October 23rd 2023, where 31,000 tree seedlings of native and fruit trees were planted in the Park Passarela Espaço Alternativo (1, 7). This was done with the support of the Municipal Secretariat of Environment and Development (1). This activity is part of the project Virada Ambiental, which seeks to promote the planting of native trees in municipalities across the country, raising awareness of the importance of planting native species and training municipal civil servants and the general public (3, 5). The National Confederation of Municipalities also supports this project and aims to mobilise society to encourage the planting of native trees to rescue biodiversity and recover environmental services, favouring social welfare by promoting tourism, and outdoor sports activities (6), providing shade, protecting the soil and combating high temperatures (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)

The PARC Rain Garden project in Plymouth, Michigan, is an innovative initiative led by the Plymouth Arts and Recreation Complex (PARC) and Friends of the Rouge, aimed at addressing stormwater management and enhancing local environmental quality. Supported by a $400,000 grant from Michigan’s Department of Environment, Great Lakes, and Energy (EGLE) through its Nonpoint Source Program, this project will involve the construction of over 31,500 square feet of rain gardens located on the property of Plymouth Arts and Recreation Complex (PARC). These gardens are designed to filter up to 240,000 gallons of stormwater per rainfall event, preventing runoff from entering local waterways like the Tonquish Creek. The rain gardens will also mitigate flooding, reduce pollution, and create a more stable water flow in the Rouge River watershed, which is heavily impacted by urban development.
In addition to their environmental benefits, the rain gardens will provide aesthetic and ecological value to the PARC campus. The plantings, featuring native Michigan species, will create habitats for pollinators such as bees, butterflies, and birds, complementing the existing beehives on the PARC rooftop. The project aims to showcase the feasibility of integrating green infrastructure into routine construction, encouraging its adoption in other urban areas and residential spaces.
Ultimately, the PARC Rain Garden project will not only improve stormwater management but also serve as a model for sustainable urban development, enhancing the landscape while fostering environmental stewardship in the Plymouth community.
(Ref.1,2)

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).

Perch Creek is one of the many meanders that drain into Dog River (Ref 2), located just west of Mobile Bay (Ref 3). These areas include sensitive, tidally influenced marshes and flats where the brackish water of the Bay meets fresh waters (Ref 1). The Perch Creek Nature Trail & Preserve project aims to protect 96 acres on Perch Creek (Ref 3). It is part of efforts to revitalise Mobile’s coastal community and improve the water quality of the city's urban river (Ref 2), following the devastation of the BP oil disaster in 2010.
The project focuses on two main aspects: creating a low-impact recreational destination to spark economic redevelopment, and preserving Mobile’s coastal wetlands (Ref 1).
The conservation aspect involves wetland acquisition, marsh restoration, and invasive species management, improving water quality in both waterbodies (Ref 1). The area, rich in wildlife, requires habitat protection, including for migrating birds, foxes, alligators, manatees, and bald eagles (Ref 1). Brackish marshes on the property serve as nurseries for fish, while forested areas provide natural corridors for wildlife (Ref 3). The wetlands also play a role in flood control, acting as natural sponges to absorb rising tides and cleanse stormwater runoff before it reaches Mobile Bay (Ref 1). Additionally, they store stormwater, helping mitigate flooding as storms intensify (Ref 3).
The recreational aspect includes developing nature-based recreation, such as nature trails and kayak launches, as well as expanding public access to natural resources (Ref 3). In 2018, the Perch Creek section was added to the Alabama Coastal Birding Trail, with educational signage for kayakers (Ref 1).
This comprehensive project preserves vital habitats and flood-absorbing wetlands, while providing outdoor recreation opportunities and supporting the coastal community's recovery (Ref 2). It combines high-quality water resources, wildlife connectivity, scenic beauty, and outdoor recreation (Ref 3).

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 Loma del Marión recovery project in Cartagena, Colombia, is a community-driven initiative supported by EPA Cartagena that focuses on restoring and conserving the remaining 1.2 hectares of tropical dry forest. Initially covering 33 hectares, the area has suffered degradation due to illegal encroachments, deforestation, and waste burning. The project has included planting over 3,000 plants and fostering community involvement in environmental conservation (ref 1). The main goals are to restore the ecosystem by reforesting native species, preventing landslide risks, and developing an ecopark that will serve as an educational and recreational space. Planned facilities include a library for learning about local flora and fauna, hiking trails, and a community garden to enhance local food security (ref 1,4). A notable educational initiative in the project is the formation of "Vigías del Ambiente" (Environmental Watchers), a group of 40 youths from the Red Nacional Jóvenes de Ambiente, supported by EPA Cartagena and CDKN. This initiative educates young people on climate change, conservation, and waste management through workshops and activities (ref 2, 3). In addition, the EPA is leading detailed studies of the tropical dry forest to identify and protect endemic species (ref 5). The project has resulted in significant environmental and social benefits, such as planting thousands of trees, boosting community engagement in conservation, and establishing youth groups dedicated to sustainable development and climate action (ref 3, 5).

Kungsgärdet Byaodling is an urban farm set up by local farming association Kungsbacka Tillsammansodling, in Kungsbacka south of Gothenburg. Since 2023, the project has been funded by a 78 000 EUR grant via the non-profit organisation Lokalt ledd utveckling Halland (locally led development) using funds from the EU and the Swedish Board of Agriculture (Jordbruksverket) [Ref. 1, 2, 4]. The goal is to grow food in a sustainable and circular way, building soil health and promoting biodiversity. Using a total area of 4500 m2 on former unused grassland, the urban farm includes: 1100 m2 of effective growing area, 1000 m2 of flowering meadows, fruit and berry trees and bushes, and functional and social areas. The meadows and trees are intended to contribute to biodiversity, while social areas are meant to create a sense of community and benefit the well-being of the people active at the farm [Ref. 1, 3]. The farming association has been around for a few years, but the project funds will allow them to expand and develop the farm over three years, invest in new equipment and arrange free lectures for the public about sustainable farming practices [Ref. 1, 4]. The grant will also allow them to take in more members without anyone having to pay anything, promoting social inclusion.

The Green and Blue Axis (Eixo Verde e Azul, EVA) is an inter-municipal green corridor project connecting the municipalities of Sintra, Oeiras, and Amadora through a 15-kilometre green ecological axis along the Jamor River (Ref 2). It aims to renaturalize the river, improve water quality, and control flooding while promoting sustainable mobility through pedestrian and cycling routes (Ref 5). The project also enhances public access to green spaces and cultural heritage sites, such as the Queluz National Palace (Ref 6). EVA supports the Lisbon Metropolitan Area’s regional strategy for climate change adaptation, risk prevention, and low-carbon economy (Ref 4). Funded by the European Regional Development Fund and municipal budgets, the project has an overall investment of €11 million (Ref 1). EVA exemplifies inter-municipal cooperation, overcoming policy conflicts to achieve shared environmental, social, and economic goals, making it a model for integrated territorial development (Ref 4). The project’s long-term impact includes reduced carbon footprint and increased territorial cohesion.