Green densification model

The Rimac River Special Landscape Project, developed by the Municipal Programme for the Recovery of the Historic Centre of Lima (PROLIMA), is a municipal proposal that arose as a response to the significant degradation of the Rimac River as it passes through the historic centre of the Peruvian capital. The river has lost its character as a green corridor and potential public recreational space for citizens (1, 3). The main problems affecting the river are related to the erosion and risk of flooding of the river space, the ecological degradation of its channels and banks, the disconnection and low quality of adjacent public spaces and the urban fragmentation caused by car-oriented mobility (2). To recover its essence as an ecological green corridor, it was proposed to give back to the Historical Centre its riverside identity and to recover the water, environmental and scenic landscape. This project aims to restore the Rímac to its role as a geographical heritage and backbone of the city of Lima, creating a system of accessible and sustainable public spaces that will help to recover this water, urban and historical landscape, as well as providing a better quality of life for the residents and users of the Historical Centre (1).
The project consists of 4 stages of intervention: Puente del Ejército - Puente Santa Rosa / Puente Santa Rosa - Puente Balta / Puente Balta - Límite
of the CHL to the east (5). Among the interventions that make up the Special River Landscape Project are: the renaturation of the 4 km of the Rimac River as it passes through the city, the construction of 14 parks, 7 squares, 1 tree planting project, 24 street renovation projects, 7 bridges/pedestrian walkways, 10 building rehabilitations and 2 new public facilities (4). It is planned to start implementing the project by the end of 2024 (4).

To protect the Lomas de Primavera from urban pressure and other threats, the Lomas de Primavera Ecological Association has implemented strategies for its conservation. One of the strategies this organisation has promoted is reforestation activities. Working together with the Municipality of Lima and other interested actors, they have sought to expand Lima's green spaces, improve air quality, enhance flora, and promote tourism, among other benefits (1). Lima's Municipality has supported the project by donating 20,000 trees for reforestation and to prevent land encroachment (1), social organisations and environmental activists have joint efforts to plant more than 250 trees to support the conservation efforts (2, 7).
The Lomas de Primavera Ecological Association leads the project, organizing community management efforts to conserve the Lomas de Primavera sector. This association is based in the Agrupación Familiar Primavera Lomas de Carabayllo community (2). The association's conservation activities involve collaboration with various stakeholders at different levels. Locally, it works with community leaders and organizations. At the district level, it coordinates with the Carabayllo municipality and the NGO CIDAP to improve urban conditions. The metropolitan-level collaboration includes the Municipality of Lima and the ACR 'Sistema de Lomas de Lima' for ecosystem protection and valorization. Nationally, it partners with MINAM, SERNANP, MINAGRI, UNDP, UCV, and the Network of Peruvian Lomas to enhance ecosystem services, restore degraded areas, and conduct research on the Lomas (2).
The preservation and reforestation of these ecosystems is essential, as they have social, cultural and environmental value, including the following ecosystem services: provision of genetic resources, soil formation, pollination, aesthetic services, ecotourism, food, education, and archaeological and historical services (3)

Rinia Park has been a significant social and recreational area in the center of Tirana since the 1950s. Over the years, it has undergone several phases of development and restructuring, each linked to the socio-political regime of the time (Ref. 1). Its most recent rehabilitation was driven by the need to revitalize public spaces and improve the quality and accessibility of urban green areas. In 2019, extensive work on enhancing the park’s infrastructure and amenities began. By June 2020, installations were completed, including new and diverse playgrounds for children, improved lighting and drainage systems, expanded walking paths as well as designated chess and dog areas (Ref. 1,2,6). Both children and the elderly benefit from these new features, which promote social interaction and make the park more inclusive for different age groups (Ref. 2).
To protect the Independence Monument from vandalism, a surrounding water feature was added. An additional benefit of the the new lighting installation is the extended access of the park well into the evening (Ref. 1,6).
Given the park’s profound history, it stands as a symbol of urban renewal and continues to serve as a central gathering spot for people and cultural events (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).

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).

Ballymun is a suburban area on the north side of Dublin, Ireland. Originally developed in the 1960s, Ballymun was built to address Dublin’s post-war housing shortages, with iconic high-rise towers and flat complexes. However, over the years, the area faced social and economic challenges, leading to a reputation for issues such as poverty, unemployment, and lack of services.
In response, the Irish government launched the Ballymun Regeneration Project in the late 1990s. As part of the Ballymun Regeneration, Poppintree Park has been transformed into a 45-acre public space at the heart of Ireland’s celebrated urban renewal project in Ballymun Town Centre. This redevelopment followed an extensive public consultation process, incorporating input from local residents, sports clubs, community groups, and youth organizations.
Poppintree Park now offers a range of upgraded amenities, including a Tree Trail featuring 15 native tree species, enhanced biodiversity, extensive wetlands, sustainable drainage systems, and spaces for passive and active recreation. The park also features a 1.25-acre playground for children aged 0-12, an amphitheater with a permanent pond, and a fully accessible pathway network with abundant seating and viewing areas. Over 50,000 plants have been added to enhance the park’s natural beauty.
The park’s transformation, led by Ballymun Regeneration Ltd., involved significant engineering and landscaping efforts. Mitchell + Associates provided the detailed landscape design, construction drawings, and supervised the landscape works.
Completed in 2010, Phase 1 of Poppintree Park’s redevelopment represents an investment exceeding €6 million. The project includes substantial earthworks, drainage systems, gabion walls, three limestone-paved entrance plazas, structural retaining walls, a cantilevered pond walkway, diverse path surfaces, and high-quality playground construction. (1-7, 10)

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).

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)

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).