Berlin has a population of 5 066 361 inhabitants (larger urban area, 2015). Its main challenge is to decouple the city‘s growth from negative impacts on climate and the environment. In this respect, maintaining and/or increasing connectivity of green infrastructures in the city is seen as a major challenge, due to increasing demand for building land in this growing city. Protecting and transforming vacant city areas into green spaces are a response to new challenges for the design of green areas:
- the diversification of society
- increased demand for recreation
- climate change.
Berlin has approximately 40 % of green (parks, forests etc.) and blue (rivers, channels, lakes, ponds, etc.) areas within its borders. It aims to create connectivity across the city and a ‘green belt’ as a border boundary for urban growth and a protection against urban sprawl.
Berlin has a specific multi-level administrative structure which determines how different layers of government interact and how competences are distributed. The city of Berlin (Stadt Berlin) fulfils both functions of the municipal and the state level (Land) in the German federal system. It is subdivided into districts (Bezirke) which to some extent are responsible for land use and environmental planning. Creating green solutions and infrastructure is a common goal across the different hierarchical levels of all planning in the City of Berlin which is anchored in most urban planning documents.
NBS project 1: BENE: (urban greening)
Within the city’s urban programme for sustainable urban development, the specific strand related to enhancing the quality of urban spaces focuses on areas of the city with a higher concentration of social problems (e.g. poverty, unemployment, lack of green areas) (Senat Berlin, n.d.a). The programme provides subsidies to improve existing green spaces, including:
- measures for creating connections;
- sustainable urban water management;
- the improvement of recreational areas within and in the surroundings of deprived neighbourhoods.
It aims to combine measures for improving recreational spaces with those for improving microclimate and providing for sustainable water management (Senat Berlin, n.d.-a).
NBS project 2: Green Moabit:
The district of Moabit’s urban development concept, called ‘Green Moabit’ (Senat Berlin, 2014b), aims, among other things, to adapt the densely urbanised area to climate change. It proposes quantitative targets for:
- the greening of rooftops, facades, streets and courtyards;
- the transformation of impervious surfaces into green surfaces.
The concept also suggests subsurface solutions for rainwater harvesting.
The concept includes physical targets for the volume of humidity for evapotranspiration to be achieved in urbanised areas. These targets are based on the calculation of evaporation volumes obtained in a forest. Half of the evaporation required will be guaranteed by increasing vegetation (green roofs, walls, pocket gardens, etc) and the other half by using stored rainwater to be evaporated on rooftops, in public paved spaces, and used for irrigating green public spaces (Senat Berlin, 2014b).
NBS project 3: Transforming vacant urban areas
The city area includes some large, centrally located vacant areas which have not been utilised for decades after the Second World War. These include the areas of Gleisdreieck and the Schöneberger Südgelände, both of which contain disused railways, and the former city airport Tempelhof. The development of these areas followed different concepts:
- The ‘Parks auf dem Gleisdreieck’ and the Schöneberger Südgelände aim at matching the diverse recreational needs of different social groups, including, for example, nature areas, meeting places, sports, playgrounds and urban gardening.
- The ‘Tempelhofer Feld’ offers mainly areas for outdoor sports like skating. It has 300 hectares (ha) of wide and open green space with stretches of asphalt left over from its time as an airport. Nevertheless, this area also offers niches for other types of uses (urban gardening, playgrounds, picnic areas, etc).
NBS project 4: School gardens
The GREEN SURGE Urban Learning Lab in Berlin set up a project for school gardening, in a secondary school covering all aspects of urban gardening, including further awareness about healthy food. Gardening activities were extended beyond the school area to a neighbouring vacant area (van der Jagt, Botzat, DeBellis, Cvejić, & Mårsén, 2016).
NBS project 5: Mixed forests programme (Mischwaldprogramm)
Berlin has approx. 16 000 ha of forest within the city’s territory and further 12 500 ha in the surrounding area of the State (Land) Brandenburg. Berlin’s forests are gradually being transformed, replacing the predominant coniferous wood planted during the 19th and early 20th century with mixed woods which are closer to the pristine forest typical for this area. The resilience of forests to climate change will increase as a result of having a pristine mix of tree species.
NBS project 6: 20 Green Walks
Berlin’s Green Walks project started in 2004 as a result of a citizens’ initiative and was adopted by the city administration afterwards. The project consists of a network of over 500 km of marked routes along 20 Green Walks connecting residential city districts with recreational areas that are protected from road traffic. This project coincides with the concept of connecting green areas, as many of the areas identified in the overarching green spaces strategies are used for the Green Walks. Maintenance tasks, including signage and trail mapping are still undertaken by a private non-profit organisation (“20 Green Walks in Berlin / Senate Department for Urban Development and the Environment Berlin,” n.d.).
NBS project 7: Nomadic gardening - Prinzessinnengarten
This bottom-up initiative for temporary use of vacant urban space for community gardening started in 2009 and aims to create a community around urban gardening and food production. It is located in the densely urbanised area of the district of Kreuzberg. The concept is based on temporary use of areas awaiting new occupancy, so only removable containers are used for gardening. The lease is periodically renewed by the city administration. The food produced is used for the garden’s own café/restaurant (“Prinzessinnengarten » About Prinzessinnengarten,” n.d.).
NBS project 2: Green Moabit — green adaptation to climate change
This strategy aims to increase the rate of evapotranspiration to levels similar to those found in forested areas. It targets both public and private open spaces, including rooftops, facades and courtyards. Using rainwater to irrigate public green spaces will reduce the use of drinking water. Enhanced rainwater storage and evaporation will reduce sewer overflows and costs for waste water treatment.
NBS project 5: Mischwaldprogramm (Mixed forests)
This measure aims to increase the resilience of the city’s forests to climate change by conserving and enhancing biodiversity. The change from coniferous to pristine tree species will:
- enhance and protect the forest’s capacity to store water;
- replenish ground water reserves used for urban drinking water;
- decrease levels of flood peaks in case of intense precipitation.
Re-establishing the pristine patterns of species diversity in forests helps prevent the spread of pests, and increases resilience to negative climate impacts from forest fires and droughts. Furthermore, forests are important carbon sinks. Interventions are made in the form of small scale interventions executed by small local enterprises using traditional techniques.
Urban green policies are integrated into urban strategies at all levels of the administrative hierarchy from the Land (State) level down to the urban district (Bezirke) level. Furthermore greening policies are integrated into the strategy for the greater metropolitan area, managed jointly by the City State of Berlin and the State of Brandenburg. The Joint State Development Plan Berlin-Brandenburg (LEP B-B) prepared an overall planning strategy for the region (Landesregierung Berlin, 2009), which includes goals for developing open spaces (Steuerung der Freiraumentwicklung) targeting approximately 30 % of the entire planning area to be kept free from urban development.
The plan explicitly underlines the multiple functions of open spaces and aims to limit interruptions to connectivity within the areas. The plan justifies the protection of green areas, pointing to their multiple functions as:
- recreational spaces;
- spaces for biodiversity;
- role models for improving urban climate and water management;
- carbon sinks.
Furthermore, some areas are specifically protected as areas for flood protection and prevention.
Planning goals are reflected by the statutory planning instruments. These are, at the city level (Stadt Berlin) the land use plan (Flächennutzungsplan, FNP), and at the district level the detailed construction plans (Bebauungspläne) and landscape plans.
These plans for regulating the built environment are complemented by planning instruments targeting the natural environment and landscape. At city level the Landscape and Species Protection Programme (Landschaftsprogramm einschließlich Artenschutzprogramm (LaPro)) (Senat Berlin, 2016b) specifies the goals provided by the Joint State Development Plan. The Programme aims to protect natural resources as a vital condition for human life, but also explicitly points to the benefits economic activities get from biodiversity and ecosystem services. Further goals in the programme include the availability of urban open spaces and recreational areas, as well as improved quality of urban space (Senat Berlin, 2016a, p. 5).
The Programme consists of five thematic plans:
- the ‘Habitat network’, based on target species;
- the ‘Natural environment’ plan which aims to enhance climate protection through the city’s green infrastructure;
- the ‘Recreation and use of green spaces’ plan which includes a system of green corridors for humans and priority areas to improve recreational spaces;
- the ‘Landscape’ plan; and
- the ‘General Urban Mitigation Concept’ (Gesamtstädtische Ausgleichskonzeption — GAK).
This Landscape plan is an important instrument for implementing connectivity measures based on the legally binding impact mitigation and compensation regulation prescribed under the Federal Nature Conservation Law (Bundesnaturschutzgesetz). In certain areas, this law allows for the development of compensation measures in accordance with the Landscape Programme’s strategic goals in selected areas. These measures will mainly be used for increasing connectivity throughout the city.
Furthermore, the Landscape Programme defines basic goals and parameters for quantitatively securing the availability of urban ecosystems and green infrastructure in densely built areas expressing the “ratio of the ecologically effective surface area to the total land area” in an index called “Biotope area factor” or BAF (“BAF-Biotope area factor / State of Berlin,” n.d.). Target values to be achieved are defined in landscape plans as an ordinance. They can be explicitly adapted according to the specific needs related to urban green on the sites, regarding, for instance, water retention capacity, biodiversity, etc (“BAF-Biotope area factor / State of Berlin,” n.d.; Becker & Mohren, 1990). Landscape plans which can potentially include indications regarding the BAF are under the responsibility of the districts. 11 % of the city’s area is covered by landscape plans that are either under discussion or already approved (“Landschaftsplan / Land Berlin,” n.d.).
In addition, the city has a series of non-statutory, strategic plans outlining long-term goals for specific urban development issues. This is part of the overall strategy (Berlin Strategie) developed by the city’s administration in collaboration with a citizens forum for urban development (Stadt Forum), which lists the multiple purposes of urban green areas concerning recreation and urban climate (Senat Berlin, 2014a). Partly addressing the same planning goals, the Urban Development Plan for Climate (Stadtentwicklungsplan Klima, StEP-Klima), adopted in 2011, coordinates the spatial and urban planning aspects of mitigation and adaptation to climate change.
The focus for climate change adaptation in Berlin is on urban heat (hot days/nights) and urban flooding (after heavy rain), as both of these extreme weather events are expected to occur more frequently due to climate change. Urban greening, including the greening of roofs and facades as well as the creation of green spaces are thus considered crucial for both providing cooling and dealing with increased quantities of rainwater during extreme events. The plan, which is continuously updated, in addition points to examples and pilot projects areas for priority actions and identifies role, importance and measures for development of existing green urban areas for urban climate (Hansen, 2015; “Stadtentwicklungsplan Klima / Land Berlin,” 2011).
In its Urban Landscape Strategy (Strategie Stadtlandschaft) the city has formulated an overarching strategy for the development of different types of urban green spaces, highlighting their multiple purposes (Berlin 2012). It is based on three main 'guiding principles’ for urban green functions (‘urban nature’, ‘beautiful city’ and ‘productive landscapes’). These emphasise the multiple benefits of urban green infrastructure, and present exemplary ‘lighthouse projects’ and ideas, which, in some cases, are part of sectoral strategies. For example, the forest transformation programme (Mischwaldprogramm) and a programme that increases the number of street trees financed by citizens’ donations.
With regards to single NBS projects cited, both the 20 green walks, and the vast open areas (Tempelhofer Feld, Gleisdreieck and Schönefelder Südgelände) are integrated into the ‘Berlin system of open spaces' (Berliner Freiraumsystem) set out in the city’s landscape programme.
 According to this federal law, interventions in the natural environment have to be avoided or as far as possible mitigated; in those cases where avoidance and mitigation are not possible, compensation measures need to be implemented. A recent decision of the Berlin State Administrative Court (Verwaltungsgericht Berlin) has underlined that the concept of compensation must repair or substitute all functions of the natural elements previously destroyed by the intervention creating a functional equivalent to the lost ones (Senat Berlin, n.d.b).
Bottom-up citizens’ initiatives have helped to create important green infrastructure, influencing and transforming public policies. Public policies have to a certain extent tolerated and sometimes integrated these bottom-up activities into mainstream policies (e.g. leasehold contract for the Prinzessinnengarten).
Citizens’ involvement has a decisive role in shaping the design of green policy in urban areas both in terms of inspiring innovative practice (nomadic temporary gardening) and conservation of green areas (Gleisdreieck, Tempelhofer Feld) in Berlin. The involvement of citizens is not limited to formal participation processes organised in the context of planning processes, but also takes place in the form of civic protests and resistance against official development plans. Local initiatives called for these areas to be transformed into green spaces to protect biodiversity as they opposed official plans for other kinds of urban development. For instance, the plans for residential developments at the margins of the Tempelhofer Feld area were recently stopped through a referendum (“Startseite - Tempelhofer-Feld” n.d.).
Citizens’ participation and co-governance — and the related innovative tools — were key aspects of Berlin’s entry for the 2017 European Capital of Innovation Award.
The project for Green Walks started in 2004 through a citizens’ initiative and was adopted by the city administration later on. Maintenance tasks are carried out by a private non-profit organisation and include maintaining signage and mapping trails (“20 Green Walks in Berlin / Senate Department for Urban Development and the Environment Berlin,” n.d.) .
Finally, Prinzessinnengarten represents a bottom-up initiative which obtained a temporary permit to use a vacant urban area.
Further to the nomadic gardening project, which provides some business opportunities (restaurant connected to the project) maintenance of green areas is mainly contracted to small local enterprises. This is the case of the Mischwald initiative, where small scale local businesses are involved.
In the past, the high availability of vacant land and brownfields due to the city’s particular history provided possibilities for green area developments and green connections that enable connectivity projects within the city. With the shift of the capital from Bonn to Berlin and the increasing development pressures, the Federal Nature Conservation Law supported implementing connectivity measures. This law imposes a legally binding impact mitigation and compensation regulation. These legal obligations provide resources to create or improve green areas. Combined with strategic, proactive planning this allows funds to be allocated for implementing connectivity measures.
While costs for establishing green areas can be financed by resources generated as compensation measures (see above), maintenance of green areas is increasing the burdens on the Districts (Bezirke) as they do not receive sufficient resources for maintaining them and are even forced to reduce spending on green areas so they can afford other expenditures (Rosol, 2006).
However, limited funding forced the implementation of innovative measures and collaboration with bottom-up initiatives, giving space to citizens’ projects like Prinzessinnengarten.
The BENE programme (NBS project 1) has been co-financed by EU's ERDF funding.
The implementation of the Mischwald Programme (NBS project 2) was accelerated through national funds dedicated to the climate adaptation of forests (Bundesanstalt für Landwirtschaft und Ernährung, n.d.; “Mischwaldprogramm / Land Berlin,” n.d.).
Financing for the Prinzessinnengarten is granted as the food produced there is used in the garden’s own café/restaurant (“Prinzessinnengarten » About Prinzessinnengarten,” n.d.).
In Berlin, urban planning and green planning appear well integrated, and innovative approaches to planning are used for instance with the use of the Biodiversity Area Factor (BAK, see above) and for implementing NBS. Previous pioneering experiments, land occupation and civil protests against past urban development strategies have partly resulted in the importance of green infrastructure being more widely understood, which has partly been reflected in the current urban planning system.
A recent further driver for specific projects and initiatives is the International Horticultural Exhibition which took place in Berlin in 2017. This was used specifically to improve the quality of an existing green area in Marzahn.
The monitoring of the social and environmental status of the city does not take into account the impacts from specific projects.
A private firm is in charge of implementing the BENE programme entirely, including the monitoring and evaluation of the projects (Senat Berlin, n.d.-a).
The Urban Learning Lab implemented in Berlin under the FP7 project GREEN SURGE set up a project for school gardening, in a secondary school covering all aspects of urban gardening, including further awareness about healthy food. Gardening activities were extended beyond the school area to a neighbouring vacant area (van der Jagt, Botzat, DeBellis, Cvejić, & Mårsén, 2016). Other than that, GREEN SURGE has confirmed that the necessary policy directions for greater urban green were already established.
20 Green Walks in Berlin / Senate Department for Urban Development and the Environment Berlin. (n.d.). Retrieved March 28, 2017, from https://ssl.stadtentwicklung.berlin.de/umwelt/berlin_move/en/hauptwege/i...
BAF-Biotope area factor / State of Berlin. (n.d.). Retrieved April 6, 2017, from http://www.stadtentwicklung.berlin.de/umwelt/landschaftsplanung/bff/inde...
Becker, G., & Mohren, R. (1990). The Biotope Area Factor as an Ecological Parameter. Landschaft Planen & Bauen, Berlin., 24.
Bundesanstalt für Landwirtschaft und Ernährung. (n.d.). Waldklimafonds. Retrieved March 28, 2017, from https://www.waldklimafonds.de/?contrast=%25252Fproccontent&L=0
Hansen, R. (2015). Berlin. Case Study Report (GREEN SURGE Case Study Report).
Landesregierung Berlin. Landesentwicklungsplan Berlin-Brandenburg (LEP B-B) (2009). Retrieved from http://gl.berlin-brandenburg.de/landesplanung/landesentwicklungsplan-ber...
Landschaftsplan / Land Berlin. (n.d.). Retrieved April 16, 2017, from http://www.stadtentwicklung.berlin.de/umwelt/landschaftsplanung/lplan/de...
Mischwaldprogramm / Land Berlin. (n.d.). Retrieved March 28, 2017, from http://www.stadtentwicklung.berlin.de/forsten/waldpflege/mischwaldprogramm/
Prinzessinnengarten » About Prinzessinnengarten. (n.d.). Retrieved March 28, 2017, from http://prinzessinnengarten.net/about/
Rosol, M. (2006). Gemeinschaftsgarten in Berlin: eine qualitative Untersuchung zu Potenzialen und Risiken burgerschaftlichen Engagements im Grunflachenbereich vor dem Hintergrund des Wandels von Staat und Planung. Zugl.: Berlin, Humboldt-Univ., Diss., 2006.
Senat Berlin. (2014a). Berlin Strategie. Berlin: Senatsverwaltung für Stadtentwicklung und Umwelt.
Senat Berlin. (2014b). Stadteilentwicklungskonzept GREEN MOABIT - Bericht. Potenzialanalyse, Handlungskonzept und Aktonsplan zu Maßnahmen zum Klimaschutz und zur Anpassung an die Folgen des Klimawandels. Berlin: Senatsverwaltung für Stadtentwicklung und Umwelt.
Senat Berlin. (2016a). Landschaftsprogramm Artenschutzprogramm Begründung und Erläuterung 2016. Berlin: Senatsverwaltung fur Stadtentwicklung und Umwelt.
Senat Berlin. Landschaftsprogramm Artenschutzprogramm in der Fassung der Bekanntmachung vom 8. Juni 2016 (2016). Retrieved from http://www.stadtentwicklung.berlin.de/umwelt/landschaftsplanung/lapro/
Senat Berlin. (n.d.-a). Berliner Programm für Nachhaltige Entwicklung (BENE) Förderschwerpunkt 6 | Natur/ Umwelt Quartiere. Retrieved March 28, 2017, from http://www.stadtentwicklung.berlin.de/umwelt/foerderprogramme/bene/foerd...
Senat Berlin. (n.d.-b). Bewertung und Bilanzierung von Eingriffen / Land Berlin. Retrieved April 16, 2017, from http://www.stadtentwicklung.berlin.de/umwelt/landschaftsplanung/bbe/
Stadtentwicklungsplan Klima / Land Berlin. (2011). Retrieved April 16, 2017, from http://www.stadtentwicklung.berlin.de/planen/stadtentwicklungsplanung/de...
Startseite - Tempelhofer-Feld. (n.d.). Retrieved April 7, 2017, from https://tempelhofer-feld.berlin.de/
van der Jagt, A., Botzat, A., DeBellis, Y., Cvejić, R., & Mårsén, A. (2016). Iterative place-based knowledge gathering in urban learning labs (Greensurge deliverable No. 7.2).
Holle Thierfelder, Senat Berlin; Rieke Hansen, Universität München