Temporary Urban Nature-Based Solutions — Ideas from Germany and Italy
Ideally, all unusable spaces within the urban landscape would be dedicated to green parks, infiltration units, urban gardens and, where possible, renaturalised river channels.
However, these types of projects require considerable time and resources to plan, implement and maintain. This can present a challenge to cities in which inaccessibility to green social spaces, inadequate stormwater management, biodiversity loss and other challenges confront the urban landscape and require a quicker response. What approaches can already be undertaken while waiting for the required political approval of and funding for such longer-term projects?
Nature-based Solutions (NBS) are, in short, solutions inspired or supported by nature (UNaLab 2020). In an urban context, these are then called Urban Nature-Based Solutions (UNBS). What is important for these solutions is not only the use of natural elements but in particular their integration into a social system that encompasses local conditions, promotes equality and participation and fits into an overall strategy in the long term (IUCN 2016). A single flowerpot in the city is therefore not a UNBS. UNBS refers to projects such as bioswales, green boulevards, restored wetlands, green roofs, green corridors, infiltration basins, permeable paving systems, parks, etc.
General benefits of NBS include improving climate resilience, liveability and physical and mental health, as well as income generation, cleaner water, reduction of flood damage, reduced energy costs and creation of opportunities for social and economic innovation, etc. (Padilla, Mok, Cavvari Paz 2020)
NBS are a fundamental part of action for climate because they can provide over “one-third of the cost effective climate mitigation needed between now and 2030 to stabilize warming to below 2 °C, achieving nature’s mitigation potential of 10–12 gigatons of CO2 per year.” — United Nations n.d.
Breathing life into urban environments with temporary UNBS projects
Before undertaking the planning and implementation of larger, more resource-intensive UNBS projects, the application of temporary UNBS projects can provide cities with opportunities to pilot various solutions.
A solution that is both temporary and mobile can currently be found in Milan, Italy. The emblematic Piazza Castello and Via Beltrami are undergoing a major transformation process under the project name “La nuova Piazza Castello”, which emerged as the winning design from a 2017 international competition by architects Emanuele Genuizzi, Vincenzo Strambio De Castillia, Giovanni Banal and Enrico Boy (Comune di Milano 2022).
While civil engineering work is being carried out on one part of Via Beltrami, pedestrian and bicycle traffic continues to flow along the road. The project has ambitious climate and vegetation goals: 186 new trees, 3600sqm of shrubs, 3000sqm of lawn, 14024 new shrubs and flowers, 23 new species and a reduction of 8000sqm of asphalt should be achieved by the redesign.
Many construction sites can be eye-sores, but the planners in Milan have come up with a different visually-appealing solution that already ties in with the values of later use and design. Instead of using the usual barrier grids or fences to provide safety around construction sites, so-called ‘living walls’ are used in some areas, which both enhance a site’s appearance as well as reduce the occurrence of the urban heat island effect.
Additionally, for some years now, bee mortality and the loss of biodiversity in the insect world have been gaining social importance and space in public and professional discourse. Start-ups such as Bienenautomat from Dortmund, Germany, and 3bee from Villa Guardia, Italy, are developing innovative ideas to contribute to improvements, such as bee feeders and sensors for monitoring beehives. Temporary green and flowering areas can already provide a habitat or food source for some animal species.
As another example, the altstadt.raum project in Bielefeld, Germany, whose pilot projects were co-organised by BABLE, is committed to reducing car traffic in the old town. At the same time, however, new uses first needed to be tried out during the test phase in order to gather ideas for the future and to demonstrate possibilities for all stakeholders. For this reason, play and seating facilities were implemented at certain points through the city centre as well as mobile trees and flower beds. Such small stepping stone biotopes, similar to the flowering street areas in Bonn, are already having positive effects on biodiversity and the microclimate (ibid).
Temporary UNBS also offer the potential that they do not have to remain temporary, depending on the project framework. An inspiring example is the Prinzessinnengarten in Berlin, Germany. Founded in 2009 as a temporary project on Moritzplatz in Kreuzberg, the use of the garden has been consolidated through the founding of a collective and has since moved to a larger space in Neukölln (Prinzessinengarten kollektiv berlin 2020) where it can accommodate large-scale farming. The project created a temporary impression with the mobile boxes and sacks that serve as beds for the plants.
Temporary solutions with lasting influences
With all the advantages of temporary solutions discussed, it must also be clearly stated that a broad-based and long-term implementation of UNBS must be preferred in principle (e.g. habitat space for larger animals, rainwater, as biotope) to make necessary contributions to the fight against climate change. However, in the otherwise unusable (re)construction phases of projects, temporary UNBS can make an initial positive contribution and arouse commitment from the community at all levels.
Want to read more about nature-based solutions? Find examples on the BABLE platform!
Make sure to also take a look at our other public spaces-related Medium articles, and always feel free to reach out to us for any inquiry.
