Technical change (e.g. built infrastructure of cities and their parts, roads, buildings and so on)

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)

In 2015, The Greening of Detroit and the Joy-Southfield Community Development Corporation collaboratively installed a bioswale in Stein Park, Detroit, as part of a broader effort to mitigate flooding in the Cody Rouge neighborhood. The area, particularly affected by heavy rains and flooding due to its proximity to the Rouge River, suffered significantly during the 2014 Great Flood, highlighting the need for improved stormwater management. The bioswale, a Green Stormwater Infrastructure (GSI) feature, was designed to capture and infiltrate up to 6,000 gallons of stormwater, diverting it from the city’s aging combined sewer system. By reducing the risk of sewer overflows, this installation also decreases the flow of untreated water into local waterways.

Funded by an $83,000 Kresge Foundation grant, the bioswale incorporates a mixture of native plants, prairie wildflowers, and ornamental grasses to filter sediment and pollutants. In addition to stormwater management, the project aims to enhance community engagement and economic revitalization. Students from Cody DIT High School's Green Team participated in the planting and design process, learning valuable skills in landscape architecture and green infrastructure. The project also ties into the Joy-Southfield CDC's vision of establishing a "green zone" to promote community safety, economic growth, and environmental stewardship.

Future plans include further green infrastructure development, such as additional bioswales and a parking lot with pervious pavers, contributing to Cody Rouge’s transformation into a model neighborhood for green development. This project not only addresses urgent environmental concerns but also fosters community pride, safety, and economic opportunities, positioning the neighborhood as a leader in Detroit’s green infrastructure movement.
(Ref.1-4)

The Tagus Estuary Linear Riverside Park is a significant environmental and recreational project in Vila Franca de Xira. As part of a broader urban regeneration initiative, the park aimed to enhance the natural and cultural landscape by promoting ecological regeneration while providing public access to the Tagus River (Ref 1). Created in 2013, the park has won several international awards and since then, the park has undergone several extensions. In 2017, another 700-meter walkway was added towards Santa Iria, and the inhabitants of this urban area of Vila Franca de Xira widely use it (Ref. 6). The park covers over 14 hectares and includes pedestrian and cycling paths, environmental education facilities such as the Bird Observatory, and the Environmental and Landscape Interpretation Centre (Ref 2).
Recently announced in 2023, the park's newest expansion is set to extend the riverside trails further, creating a continuous route from Lisbon to Alhandra (Ref 5). With future phases planned, the project is expected to significantly increase public interaction with the riverfront and its biodiversity (Ref 5). In this new project phase, the Vila Franca de Xira Municipal Council begins the requalification and environmental and landscape conservation of another section of the riverfront of the Municipality of Vila Franca de Xira, between Alverca and Sobralinho, covering an extension of approximately 4.9 km and an area of ​​approximately 14.1 hectares (Ref. 7). The extension of the park will be developed similarly to its existing infrastructure. New paths for pedestrians and cyclists will be created using elevated wooden structures (walkways). In total, two new cycle-pedestrian trails will be created – Trilho das Comportas (3.32 kilometres long) and the Trilho dos Salgados (594 metres long) –, and the Trilho do Tejo will be extended by a further 990 metres (Ref. 5).

In an architecturally important area of Berlin, situated between the Landwehr Canal, the Kulturforum (the Berliner Philharmonie and the Berlin State Library) and the new construction on Potsdamer Platz, a combination of green and grey infrastructure has been realised to minimise the burden on Berlin’s existing water infrastructure.
Green and non-green roofs harvest annual rain, which flows through the site’s buildings and is used for toilet flushing, irrigation, and fire systems. The roofs retain and then release water to the large on-site buffer pond, which has five underground storage tanks. Next to the roofs, a series of urban ponds and connecting canals have been implemented, with a combined area of approximately 1.2 hectares. They are filled with rainwater, creating an oasis for urban life. Vegetated biotopes are integrated into the overland landscape and serve to filter and circulate the water that runs along streets and walkways. The lake’s water quality is excellent, forming a natural habitat for animals and cooling the surroundings, while fresh water usage in the buildings has been reduced. (Ref. 1; Ref. 2; Ref. 3; Ref. 6)
The project was implemented in the 1990s as part of the development of Potsdamer Platz in the wake of the reunification of Germany. Several architects collaborated on the implementation that was completely privately funded. Beyond its ecological and technical features, the site is a blue natural site in the heavily built city centre of Berlin and allows people to linger and enjoy natural features. The drainage system won several sustainability prices and is considered a successful integration of nature and technology-based mechanisms to foster climate change adaptation. As the rainwater system stores rainwater in underground tanks and ponds, the urban sewage system is relieved during heavy rain, and water can evaporate. Therefore, the small water circle is closed, and the microclimate is cooled. (Ref. 2; Ref. 6)

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.

Located in the Lima district of San Isidro - the heart of commercial activity in Peru - the Real Dos Tower is a prime office building in the Centro Empresarial Real de San Isidro. It was inaugurated in 2018, and it is distributed over 23 levels (14 floors and 9 basements) and enjoys a landscaped green roof (1162 m2) at the crown of the building and numerous outdoor vertical gardens at full height (2365 m2) on the three main fronts (1, 4). This project was a finalist in the 2018 Mipim Awards, considered the ‘Oscars’ of world architecture, and stood out for its architecture and design, due to its attributes of innovation and sustainability (2).
This building has managed to create harmony between design and efficient use of resources. It is characterised by a glass façade with colourful movable shutters and symbolic Peruvian designs (2, 3, 6). It has green walls on the three main fronts, four daylight fronts and a roof garden (2). The architect, Jean Nouvel, worked together with ARVE Peru on the overall landscape plans for the Real Dos tower (1, 3).
This is part of the façade remodelling project of the Camino Real Towers in the Real Business Centre, led by the real estate company Grupo Centenario (1, 2, 3, 4, 5, 6). This overarching Project has sought to develop 4,475 m2 of vertical gardens and roof gardens, which have a technified irrigation system to generate efficiencies in water use, meeting the plants' water requirements in the different seasons of the year. Their implementation helps to filter CO2 and renew the O2 in the office complex.
The ARVE group describes these actions as conducive to creating thermal barriers and sound insulation, a better environment for rest, work and entertainment and increasing property value (7)

In 2020, the Metropolitan City of Cagliari launched a project to enhance flood resilience and ecological integrity in the Mannu-Cixerri river system in southern Sardinia. The river traverses several communes within the metropolitan area, ultimately feeding into the Santa Gilla Lagoon, a vital wetland ecosystem west of the city.
The project, with a budget of €21 million, focuses on three key communes: Assemini, Decimomannu, and Uta. Rather than solely emphasizing structural flood defenses, the initiative integrates nature-based solutions (NbS) to mitigate flood risks while restoring riverine ecosystems. The Metropolitan City of Cagliari, in collaboration with the Sardinian Regional Public Works Department, is responsible for its implementation.
Key interventions include reinforcing and revegetating embankments, improving water flow along the Rio Mannu, and constructing new levee sections in a manner that enhances natural water retention. Additionally, the project involves upgrading bridges to facilitate better floodwater management. These measures align with the Sardinian Flood Risk Management Plan (PGRA) and aim to reduce flood hazards while promoting ecological benefits.
The project timeline began with a two-year preparation phase for the Preliminary Design Document, followed by a year-long tendering process for construction. These efforts represent a crucial step toward long-term flood resilience and environmental sustainability in the region. (Ref. 1, 2, 3)

Seaweeds are of immense value to marine ecosystems, and Kelp, the largest of them all, forms spectacular underwater forests that provide habitat for fish, clean the water, and sequester carbon. Unfortunately, large swathes of these subaquatic forests have disappeared from the coasts of many European countries, including Portugal (Ref. 2).
The "Sea Forester" project in Cascais aims to restore local kelp forests, which are essential for marine biodiversity and carbon sequestration. In collaboration with the Câmara Municipal de Cascais and Mossy Earth (social enterprise), the project assesses the historical and current state of seaweed populations and identifies environmental stressors. It employs innovative techniques like the "green gravel" method to restore kelp ecosystems. This project supports the region’s blue economy and resilience to climate change through carbon offsetting and enhanced ecosystem services (Ref 1; 6; 7). Supported by the EEA Innovation Grant, it combines scientific research and community engagement, positioning Cascais as a leader in marine conservation efforts (Ref 6).

Biotope City Wienerberg is located in the southern part of Vienna on a 5.4-hectare site that once housed a Coca-Cola factory. It lies at the edge of the Wienerberg recreational area, surrounded by business parks and tower blocks to the west and predominantly detached houses to the east (Ref. 1).
The project embodies the concept of an "urban biotope" (Ref. 2), grounded in the principle that nature's mechanisms of self-regeneration are essential for mitigating the challenges of urban living and climate change. By integrating urban and natural spaces, Biotope City fosters both human-nature connections and social interactions through activities like community gardening. The project’s centerpiece is its extensive green infrastructure, including trees and green roofs, which serve to cool the microclimate, purify the air, enhance water retention, and create carbon sinks while providing habitats for local wildlife. These green spaces aim to improve physical health through cooling effects on hot days and support mental well-being with their calming influence (Ref. 1; Ref. 2).
Biotope City encompasses:
Around 980 flats, including 400 subsidized flats and 200 SMART flats
A school, a kindergarten, and 2,000 square meters of children's and youth playgrounds
600 square meters of community gardens and 3,850 square meters of ground-floor gardens
250 trees, 8,900 square meters of meadows, and 13,600 square meters of green roofs
2,200 square meters of façade greening
The inner courtyards and roof areas are designed for gardening, while façades are greened, and balconies are equipped with integrated plant troughs. Even the spaces between buildings are climate-effective, featuring unsealed catchment and seepage areas to manage water sustainably (Ref. 1).
The project’s implementation took 18 years and involved collaboration among various stakeholders. The concept was initiated by the Biotope City Foundation and funded by eight different investors (Ref. 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).