Green densification model

The Green Corridor Südpanke is a transformative restoration project that unveiled 700 meters of the river Südpanke, connecting Invalidenpark and Südpankepark in the heart of Berlin. This initiative, part of Berlin's broader mission to restore the Panke River, was spearheaded by the state of Berlin with a focus on ecological restoration, biodiversity enhancement, microclimate cooling, and creating recreational spaces to improve the quality of life for residents (Ref. 2; Ref. 3).
Historically, the river in this area was channeled underground. The project brought the Südpanke back to the surface, integrating ecological principles and landscape planning into the design. The restored section of the river now flows openly in a natural watercourse bed, making it accessible to the public (Ref. 5). The restoration was completed in 2021, transforming the area with features such as playgrounds, lawns, benches, and a continuous biking and walking path that weaves through the green spaces.
Work on the project began in 2010 but was interrupted by the construction of the neighboring headquarters of the Federal Intelligence Service. As a result, parts of the green corridor were opened to the public in 2012, with the full restoration completed nearly a decade later, in 2021 (Ref. 3; Ref. 6).
The project established a seamless connection for cyclists and pedestrians from Invalidenpark in the south to Südpankepark in the north. The new open water section cools the microclimate in Berlin's densely built-up center while providing a critical habitat for plants and animals. Embankments and meadows near the Federal Intelligence Service's property support wild bees and other pollinators, fostering biodiversity. The Green Corridor Südpanke is a vibrant example of how urban ecological restoration can contribute to sustainability, quality of life, and resilience in a growing city. (Ref. 2)

The Chaowan Nursery Garden Base Project (潮玩苗圃基地), located along the Dianchi Greenway in Kunming, was established by the Kunming Gardens Virescence Bureau (昆明市园林绿化局) in 2022 as part of the city's efforts to transform into a "city of parks" (Ref 2, 3). Covering 639 mu (42.6 hectares), the Chaowan Nursery Garden has introduced over 1.4 million plants, including trees, flowers, and grasses, greatly expanding the city's green spaces (Ref 3). It serves as a key resource for the Kunming Greening Service Center (昆明市绿化服务中心), providing seedlings for major greening projects along roads like Guangfu Road, Airport Road, Beijing Road, and the Second Ring Elevated Road (Ref 4).
Innovatively designed, the nursery also functions as a park, offering an "immersive" experience with various themed areas such as rainwater gardens, rural gardens, Chinese gardens, and scenic balconies. These spaces allow visitors to stroll through and enjoy the beauty of various flowers and natural surroundings (Ref 4). The project also collaborates with local universities on seedling research, capacity building, and resource sharing, further enhancing its multifaceted role (Ref 3).
Since opening to the public in 2023, the Chaowan Nursery Garden has become a popular destination for families, young people, and children, offering both recreational and educational experiences (Ref 5, 6, 7, 8).

A green area was turned into a "reuse park" to save trees, bushes and other plants that had to be moved from elsewhere due to construction work. The project resulted from constructing the new business school at the University of Gothenburg, where circular economy initiatives are being tested. Plants that would have to be removed from that site were moved to the park at Medicinareberget temporarily. They will later be replanted elsewhere on campus, saving money and reducing the environmental impact of buying new plants. The lead actor in the project is the public real estate company Akademiska Hus, which owns and manages the affected parts of the university campus. The reuse park was established in 2021, and it's implied that it can continue to function as a storage site for plants from different construction locations. The project is highlighted as a learning opportunity for how the reuse of plants can be implemented in future construction projects. The project is connected to the regional initiative Återbruk Väst within the national platform CCbuild, which promotes circular solutions in the construction centre [Ref. 1-5].

Brookley by the Bay is a 98-acre new waterfront park project along Mobile Bay's western shore (Ref 1). The park aims to reconnect people with the Mobile waterfront and coastal ecosystem (Ref 2). The area, once an abundant mosaic of tidal marshes, forested wetlands, and shallow lagoons, became a port, leading residents to lose contact with the natural landscape (Ref 2).
The park serves both recreational and environmental purposes, aiming to create and restore areas that enhance habitat resilience and allow coastal ecosystems to thrive (Ref 1). It features sports facilities, including kayaking, volleyball, golf, and biking, along with social gathering and educational spaces such as an amphitheatre lawn, a performance pavilion, and picnic tables (Ref 3, Images 1-3). The park provides safe and equitable access for all Mobile residents to nature, beaches, tree canopies, open fields, and varied shorelines, all connected by pedestrian and bike lanes (Ref 2). The project also focuses on habitat enhancement and restoration for biodiversity (Ref 3, Images 1 & 4), as well as flood protection through shoreline get-downs, vegetated edges (Image 4), and undulating berms and swales that serve as a layered protection system against stormwater and coastal flooding (Ref 2).
The development of Brookley by the Bay was guided by input from over 300 community members (Ref 1), local stakeholder organizations, and project partners, with the goal of establishing a more resilient, accessible, and enduring space for generations to come (Ref 2).

The "Line Park" project in Belgrade aims to create a continuous green belt spanning 4.6 kilometres and covering over 48 hectares. As such, the project will revitalize the former railway corridor from "Beton Hala", just below the Belgrade Fortress, to the Pancevac Bridge. Inspired by notable urban parks like New York's "High Line", Moscow's "Zagrađe," and Toronto's "Rail Corridor," it will become a major recreational destination and also help to alleviate the pressures from the city's heavy air pollution and summer heat (Ref. 5, 6).
The park will be divided into ten thematic sections dedicated to aromatic plant and flower gardens, urban gardening and beekeeping, sports facilities, a newly built university campus and more. Additionally, there will be an amphitheatre and facilities for outdoor education. To further integrate green infrastructure, new buildings will have green roofs and walls (Ref. 2,5). Ultimately, the park integrates a number of amenities into the entire city.
The development of the park also introduced innovative co-creation mechanisms in terms of governance and planning. Since Belgrade is part of the multinational CLEVER Cities Initiative, the city's Secretariat for Environmental Protection suggested the use of the site as a pilot test for introducing nature-based solutions in urban planning and with diverse stakeholders' input. Several workshops, focus groups, and consultations took place between 2019 and 2021, which facilitated the diversity of ideas that have been adopted into the official construction plan (Ref. 1, 2). Despite these successes, civil society groups raise concerns over the extraordinary cost of 70 million euros, displacement of Roma communities and the interest of real estate developers that may undermine the project's original cause (Ref. 3, 8).

The Palas Campus project is a real estate investment by the private company IULIUS, involving the construction of a mixed-use development with integrated green elements, including a green terrace (1–3, 5). The project spans approximately 86,000 sq.m., of which 4,500 sq.m. are dedicated to green spaces (1–3, 5). In these green spaces, 200 trees and 7,000 bushes of various species were planted (1, 2). The landscape design was created by a team of international experts, with some plant species imported from Italy (1, 5). The primary goal of the project is urban regeneration in a specific district of the city, building on similar projects previously implemented by IULIUS (1, 2, 5). The Palas Campus landscape includes relaxation spaces and pedestrian walkways (1).
The buildings were designed to meet the standards for two green certifications: EDGE and LEED, both of which were awarded in 2024 (4, 6–10). The EDGE certification signifies a 20–40% reduction in energy and water use compared to standard buildings (4, 8). The LEED certification, awarded based on various sustainability criteria, saw Palas Campus achieve one of the highest scores (4, 9, 10). One key aspect of the certification was the reduction of the "heat island" effect (10).
The total cost of the project reached 120 million euros, with 3.8 million euros allocated to the green spaces (1, 2, 5). The project was partially financed by a 72 million euro "green" loan from the IFC, a member of the World Bank Group, which also provided expertise to help secure the EDGE certification (6–8). The LEED certification was obtained with the support of the consulting firm BuildGreen (11).

The Dreamy Draw Recreation Area is located in Phoenix, Arizona. It is situated near the Phoenix Mountains Preserve and provides access to various hiking and biking trails, as well as scenic desert landscapes. The Dreamy Draw Recreation Area project is a comprehensive initiative aimed at enhancing an existing park space. Key improvements include infrastructure upgrades, trail enhancements, and ecological restoration efforts. Through the construction of new ramadas, expanded parking, and increased accessibility features, the project seeks to create a more welcoming and inclusive environment for all visitors. This endeavor was launched as part of the City's Drought Pipeline Project.
One important component of the project is revegetation, which includes the planting of native saguaros to support ecological restoration and improve the park's visual appeal. The project addresses several longstanding challenges, such as limited parking, outdated facilities, and the need for improved trail conditions. By adding more parking spaces, installing modern restrooms, and constructing accessible pathways, the enhancements contribute to a safer and more enjoyable experience for visitors. Additionally, the revegetation efforts help restore natural habitats and mitigate the ecological impacts of urbanization on the local environment.
In total, more than two dozen mature saguaros were replanted in the newly reopened Dreamy Draw Recreation Area, creating an “immediate visual impact,” particularly along Route 51. The Mountain Parks and Preserves Committee held a meeting on Monday evening to review the revegetation work completed over the summer, with the area reopening on September 7.
Of the 58 cacti planted in this project, 27 saguaros—referred to as "reclamation saguaros" by Wayne Colebank, a landscape architect on the project—were previously stored by Phoenix Water Services at the 24th Street Water Treatment Plant near Lincoln Drive and 24th Street. (1-11)

The "Ruas Verdes+" (green streets) project, implemented in the parishes of Areeiro and Arroios in Lisbon, is part of a broader European initiative, Conexus, aimed at promoting green solutions in highly urbanized areas (Ref 3). The project primarily focuses on creating a tree-lined pedestrian corridor along Carlos Mardel and Francisco Sanches streets, establishing a continuous axis between the Casal Vistoso Urban Park and the Caracol da Penha Garden (Ref 1). This corridor is designed to mitigate urban heat island effects, enhance ecological connectivity, and improve residents' quality of life (Ref 5). The pilot phase includes planting 20 trees on Rua Carlos Mardel and removing a minimal number of parking spaces to balance urban greening with local needs (Ref 1). Additionally, planters are being introduced in the Bairro dos Actores area to test the community’s response to greening initiatives (Ref 1). The project also involves public participation through gardening workshops, encouraging residents to contribute to the greening effort by adding plants to their balconies (Ref 4). This initiative aims not only to enhance the urban environment but also to foster social inclusion and community engagement while addressing the challenges of climate change in Lisbon's densely populated areas (Ref 5).

Fjärdingsparken is a city park that has been constructed in two phases, the second finishing in 2023 [Ref. 1]. The initial phase of the plan focuses on building a new kindergarten, and it includes developing the park surrounding the kindergarten to increase locals' access to green space and recreation. The first phase also involved building a football field at the park's edge [Ref. 1, 4, 5]. The second phase continued the park's development focusing on rain water management and biodiversity. The park was constructed so that up to 900 m3 of rainwater can be managed in the park during a 100-year rain, protecting the surrounding area from flooding. This is part of a flooding strategy for the city. The park includes a meadow, aiming to provide habitat for flowers and plants supporting pollinators and butterflies. It also contains amenities such as an outdoor gym, a dog park, and a "play forest" designed for children. The climate impact of constructing the park was evaluated in an attempt to reduce GHG emissions [Ref. 1-3].

The Joe Louis Greenway is a 27.5-mile recreational pathway designed to create safe, connected, and equitable spaces throughout Detroit. It will link 23 neighborhoods across Detroit, Hamtramck, Highland Park, and Dearborn, connecting them to each other and to the Detroit riverfront. The greenway will transform a blighted, abandoned rail corridor into a park that runs through the heart of Detroit's communities. (Ref. 2, 3)
This project is guided by a Framework Plan funded by the Ralph C. Wilson, Jr. Foundation and shaped by extensive community input. Residents voiced a strong desire for the greenway to provide off-street recreation and increased access to green spaces across Detroit. Additionally, they advocated for the restoration and remediation of former industrial sites, which the Conrail section of the greenway will address. (Ref. 4) The design incorporates stormwater management to mitigate flooding, native meadow plantings to support bird habitats, and tree-lined paths for shade and improved air quality. The Framework Plan ensures the Joe Louis Greenway will transform infrastructure that once divided neighborhoods into one that unites them, reconnects natural systems, drives economic redevelopment, and fosters a resilient social network. (Ref. 13)
The concept originated in 2007 with the Friends of the Inner Circle Greenway local NGO and became part of the Detroit Greenways Coalition Network Vision in 2009. The Detroit Greenways Coalition Network Vision is a comprehensive plan developed by the Detroit Greenways Coalition (NGO), an organization dedicated to promoting non-motorized transportation and green infrastructure throughout the city. After years of advocacy and collaboration with the city of Detroit, the project’s route was finalized. In 2017, Mayor Mike Duggan announced the greenway would be renamed in honor of Joe Louis, the legendary boxer and Detroit native who championed African Americans' rights and symbolized social justice. (Ref. 1, 2,)