Increased protection against flooding

The project focused on implementing multilayer blue-green roofs in four Italian cities—Cagliari, Palermo, Perugia, and Viterbo—as part of a broader European initiative to address climate change impacts in urban environments (1,3). Spearheaded by a collaboration between multiple Italian universities and the Dutch company Metropolder, the project began in 2019 (1,3). The primary goal is to enhance urban resilience by integrating green infrastructure capable of mitigating climate-related urban hazards such as flooding and heat waves, which are increasingly severe due to climate change and urbanisation (2,3).
The multilayer blue-green roofs combine the ecological benefits of traditional green roofs with an added water storage layer, allowing them to retain rainfall and manage runoff effectively (2,3). This dual function helps reduce pluvial flooding and the urban heat island effect, while also improving thermal insulation in buildings (2,3). Each installation was planted with low-maintenance, climate-adapted vegetation, and equipped with sensors to monitor ecohydrological and thermal performance over several years (1,3). These roofs are capable of retaining up to 100% of rainfall from significant events, thereby easing the burden on urban drainage systems and contributing to climate adaptation in Mediterranean cities (2,4).

The Cagliari Canal project is an initiative aimed at revitalizing and transforming the urban and natural landscape of the Cagliari Metropolitan Area in Sardinia. The project is rooted in the city's strategic metropolitan plan and seeks to restore and enhance the navigability of the Terramaini-La Palma canal, which had become disused and neglected over time​ (3,4). The primary goal of the Cagliari Canal project is to develop a connected, innovative, and sustainable urban environment by re-establishing the canal as a green and blue infrastructure​ (2). It aims to provide alternative, sustainable mobility options, improve connectivity between municipalities, and enhance the natural and urban environments. It strives to foster a sense of community by creating a shared space for residents and integrating modern amenities that align with environmental sustainability (1,4). It involved a highly participatory process, emphasizing community involvement from the initial planning stages. The Metropolitan Authority of Cagliari, in collaboration with local stakeholders, launched a series of consultations to gather public input on the canal's design and function​(3). These consultations were part of a broader initiative called LabMet, the Metropolitan Laboratory for Innovation, which facilitated the collection of ideas and feedback (1). The project was partly developed in response to the increasing environmental challenges faced by Cagliari, including the need to adapt to climate change. The canal's revitalization is seen as a key measure for enhancing the city's resilience to climate-related risks, such as flooding and heat waves​(1). By restoring the canal and its surrounding areas, the project aims to mitigate these risks through improved water management, reducing pollution, and the creation of green spaces that can absorb excess rainwater and provide cooling effects​ (2)

Booterstown Marsh, the only remaining saltmarsh on the south shore of Dublin Bay, plays a crucial role in the Dublin Bay Protection Plan. As part of South Dublin Bay's protected landscape, this unique 4.3-hectare brackish water marsh provides vital environmental and educational value within an urban setting. It supports three key habitats, ranging from freshwater to saltwater, creating essential feeding and roosting grounds for an array of migratory birds. The marsh attracts numerous bird species, including Moorhen, Reed Bunting, Sedge Warbler, Teal, Snipe, Lapwing, Oystercatcher, Redshank, Dunlin, and Brent Geese, establishing it as the only bird sanctuary in South Dublin Bay.
Booterstown Marsh’s ecological significance is underscored by its inclusion in the Dún Laoghaire-Rathdown County Council’s Biodiversity Action Plan 2021-2025: Nature Recovery, Restoration & Reconnection. Managed by the Biodiversity Section of the council, this initiative focuses on protecting and enhancing Booterstown Marsh as part of a broader effort to restore natural habitats across the area. The council’s project addresses key factors in biodiversity loss—such as land use pressures, climate change, and invasive species—by implementing an annual monitoring program to prevent deterioration of critical EU Annex habitats and species.
An Taisce, a local NGO has managed the marsh reserve since the 1970s, dedicating efforts to conservation and public education. This habitat, along with other local ecosystems like the wetlands at Ballycorus and woodlands at Loughlinstown, serves as an essential natural defense against climate change, removing carbon dioxide from the atmosphere and helping stabilize local landscapes by slowing floodwaters in catchment areas.(1-6)

The former Kulturpark Plänterwald, once the only permanent amusement park in the GDR, closed in 2001 due to declining visitor numbers. Over time, the 23-hectare site became a ‘lost place,’ falling into disrepair. In 2014, the state of Berlin reacquired the area, and two years later, Grün Berlin initiated its redevelopment with a sustainable development concept that places significant emphasis on rainwater management.
The project’s goal is to avoid discharging rainwater into the sewer system and instead manage all precipitation on-site. This approach addresses both heavy rainfall events and extreme drought conditions, creating a sustainable rainwater management system. A central element of this concept is the historic but dried-up water basin located near the iconic Ferris wheel. Plans include redesigning and reactivating the basin, incorporating terraces and a shallow water zone, transforming it into a key part of the rainwater cycle while providing an attractive recreational and adventure area. (Ref. 1; Ref. 2)
In the future, the water basin will no longer be purely decorative but will serve as a critical artificial water reservoir. To support this function, it will be equipped with a natural horizontal filter system featuring reeds for rainwater purification. Pre-treated water will flow into the newly designed 3,000-square-metre basin near the Ferris wheel. Rainwater collected in the basin, along with water stored in cisterns throughout the park, will irrigate the site’s vegetation. This innovative approach ensures sustainable water use and contributes to the ecological revitalization of the park. (Ref. 1; Ref. 3)
By integrating sustainable rainwater management into its redevelopment, the former Kulturpark Plänterwald is being transformed into a resilient and environmentally conscious space, combining historical preservation with modern ecological practices.

The Far West Detroit neighborhood faces significant challenges with its aging infrastructure. The neighborhood’s stormwater and sewer systems are combined into a single system that is only capable of handling a limited volume. During heavy rain events, the system's capacity is exceeded, causing excess stormwater and untreated sewage to overflow into the Rouge River, which negatively impacts the environment (Ref. 1).
Detroit is investing $40 million in a transformative stormwater management system in the Far West neighborhood near Rouge Park. Described by the Detroit Water and Sewerage Department as the largest project of its kind, it will redirect 98 million gallons of rainwater and snowmelt into two new detention basins and a renovated sewer system. The new wastewater system is expected to significantly reduce water volumes in Detroit’s combined sewer system during heavy rainfall and to provide flood relief for approximately 1,200 homes that have experienced flooding in recent years. This expansion, informed by community feedback, marks one of the city's most notable investments in green infrastructure to improve its overextended wastewater management system.
The project has been planned through extensive studies and community coordination since 2016, with construction set to occur in three phases, extending through 2026. Crews broke ground on the South Basin, North Basin, and sewer overhaul in July 2022, and progress is reportedly on track. In addition to the basins, the stormwater management initiative includes neighborhood improvements to enhance recreational opportunities for residents and visitors alike. Planned enhancements in Rouge Park will introduce wetland spaces with native flora, creating greener, more inviting areas in the community for residents to enjoy (Ref. 2).

This project aims to increase water retention capacity in the landscape around urban areas and promote biodiversity by restoring wetlands and natural streams in the forested areas on the island of Hisingen in northern Gothenburg. Many wetlands and streams in the area have been drained or otherwise affected by human activity, reducing biodiversity, increasing the risk of floods and droughts and causing greenhouse gas emissions from peatland. The goals of the project are to reduce the risk of floods downstream, reduce the effects of dry periods, increase groundwater infiltration and benefit species living in and around wetlands and streams in the forest [Ref. 1-3]. The Swedish Anglers Association has initiated the project in cooperation with the City of Gothenburg and the environmental engineering company Miljöteknik I Väst AB [Ref 1]. The project's first stage is a continuation of an earlier project to make an inventory of wetlands and their status [Ref 1, 2]. For the second part, 6,9 ha of wetlands and streams on land owned by the city were restored [Ref. 1, 3]. The project will lead to further efforts in wetland restoration around Gothenburg [Ref. 2, 4].

The Fenkell Stormwater Project in the Brightmoor neighborhood of Detroit is an initiative led by the Detroit Water and Sewerage Department (DWSD) to mitigate the impact of heavy rain events on the local sewer system. By transforming 92 Detroit Land Bank Authority (DLBA) parcels into 24 bioretention gardens, the project aims to significantly reduce street flooding and basement backups in the area. These gardens, spread across approximately 50 acres of mostly vacant land, utilize permeable soils and landscaping techniques to absorb excess rainfall, which helps prevent the overloading of the city’s combined sewer system. This is particularly important in reducing combined sewer overflows (CSOs), which occur when the system's capacity is exceeded during heavy rains, leading to untreated stormwater and sewage being discharged into the Rouge River.
The project is expected to manage and treat about nine million gallons of stormwater annually, making a significant impact on both the neighborhood’s infrastructure and the environment. In addition to the bioretention gardens, the project includes the partial removal of Blackstone Street between Keeler and Midland streets to further enhance stormwater management.
Community engagement has been a critical component of the project, with residents of Brightmoor and Minock Park participating in meetings to share their preferences for the types of trees, plantings, and other features. The DWSD will maintain the gardens under its Green Stormwater Infrastructure (GSI) program, which already includes 19 other similar projects across the city. The project is currently in the construction phase and is expected to be completed by the end of 2024, modernizing Brightmoor’s stormwater infrastructure and providing long-term environmental and community benefits.
(Ref.1-3)

MINI Ireland, in collaboration with conservation charity Earthwatch Europe, has launched Ireland's first "Tiny Forest" at the Tolka River Project, a community-driven rehabilitation program in Co. Dublin. In a space the size of a tennis court (195m²), nearly 600 native trees have been planted, creating a densely packed, environmentally efficient green area.
This partnership with Earthwatch aims to raise awareness for local environmental projects and foster community bonds. Green spaces like this offer valuable areas for people to connect with nature, exercise, unwind, and reduce stress—one reason the Tolka River Project center was chosen as an ideal location. "Tiny Forests" are remarkable for their impressive efficiency within a small footprint: by planting 600 native trees closely together, the forest grows naturally with increased density, achieving up to 30% more plant density, ten times faster growth, and up to thirty times better carbon dioxide absorption. Over the next three years, this forest is expected to attract more than 500 animal and plant species, transforming into an accessible mini-ecosystem.
The project uses a variety of locally sourced native trees, including silver birch, alder, hazel, hawthorn, and gorse, which together will form the natural layers of a forest. Ireland's first Tiny Forest was planted on March 22, 2023, at the Tolka River Project site in Dublin's Buzzardstown area. The Tiny Forest, located near the center, will serve as a space for reflection and recovery, supporting clients on their journey to rehabilitation. The planting event was a day of celebration, with Tolka River Project clients and MINI Ireland staff working side-by-side to create this thriving green space.. The space is utilized to create recovery-focused programs, including mindfulness and yoga, while functioning as a social gathering area (7).

This series of projects in the Trinity Garden aims to improve sports fields, enhance drainage, and replace HVAC (Heating, Ventilation, and Air Conditioning) systems at the community center in the Trinity Garden community (Ref 1). The first project involves a complete renovation of the playground area at Trinity Gardens Park. The entire playground will be rebuilt with a new drainage system, along with the installation of a new play structure, benches, and trash receptacles (Ref 2). Another key component of the project includes the construction of a new natural baseball/football combo field, with a new infield, bases, outfield fencing, foul poles, and with improved drainage (drain piping, inlets, sodding, and irrigation) for the sports field (Ref 3). On the subject of recreation and public health, Councilman Fred Richardson emphasised the significance of Trinity Park, stating, “Good public parks are key to creating healthy children and, in turn, strong communities. I am so happy that we are able to bring these major improvements so local children will have a great place to come play, and their caregivers will have a place to watch them from” (Ref 2).
Additionally, another major project on the agenda focuses on street and drainage improvements within the community. This will address issues on Warsaw Avenue and Collins Avenue, from Main Street to Jessie Street, aiming to resolve several hazardous open ditches that currently run through the neighborhood (Ref 2).

According to data from the National Institute for Space Research (Inpe), Rondônia ranks fourth nationally among the states with the highest number of detected fire outbreaks (2). In response to this issue and to restore devastated areas in the Amazon, Terra Cura was established in 2016 by resident Luana Lopes, promoting the planting of more than a thousand trees in the Porto Velho region (1). The areas benefiting from this initiative were those degraded by deforestation, causing erosion along the riverbanks (1).
This reforestation effort took place in the scenographic city of Jerusalem of the Amazon, from 2016 to 2022, a cultural and touristic complex in Porto Velho, where erosion caused by deforestation was observed along the riverbanks next to it (2). It was developed as a collaboration with the club and the founders of the Associação Clube Teatral Êxodo, who gave the space so that we could recover the land (3).
The project focused on developing an agricultural strategy known as syntropic farming, by implementing an agroforestry system. This approach seeks to reorganize and restore the natural environment, creating better conditions for planting and allowing trees to thrive. In the reforestation process, volunteers and experienced technicians worked together Additionally, the project included a nursery used for donating seedlings and for offering forestry and agro-construction courses to the community, held in the reforestation area (2).
The Terra Cura project, in addition to working on reforestation and recovery of degraded areas, promoted environmental and cultural integration at the site, promoting sustainable fairs and bazaars, training courses in ancestral practices such as soil cultivation and bioconstruction, and thematic events, bringing together artists and local communities (3). Although they were evicted from the area surrounding the scenic city of Jerusalem (5, 6), they are still active in the area.