Last updated: March 2025
In an architecturally important area of Berlin, situated between the Landwehr Canal, the Kulturforum (the Berliner Philharmonie and the Berlin State Library) and the new construction on Potsdamer Platz, a combination of green and grey infrastructure has been realised to minimise the burden on Berlin’s existing water infrastructure. Green and non-green roofs harvest annual rain, which flows through the site’s buildings and is used for toilet flushing, irrigation, and fire systems. The roofs retain and then release water to the large on-site buffer pond, which has five underground storage tanks. Next to the roofs, a series of urban ponds and connecting canals have been implemented, with a combined area of approximately 1.2 hectares. They are filled with rainwater, creating an oasis for urban life. Vegetated biotopes are integrated into the overland landscape and serve to filter and circulate the water that runs along streets and walkways. The lake’s water quality is excellent, forming a natural habitat for animals and cooling the surroundings, while fresh water usage in the buildings has been reduced. (Ref. 1; Ref. 2; Ref. 3; Ref. 6) The project was implemented in the 1990s as part of the development of Potsdamer Platz in the wake of the reunification of Germany. Several architects collaborated on the implementation that was completely privately funded. Beyond its ecological and technical features, the site is a blue natural site in the heavily built city centre of Berlin and allows people to linger and enjoy natural features. The drainage system won several sustainability prices and is considered a successful integration of nature and technology-based mechanisms to foster climate change adaptation. As the rainwater system stores rainwater in underground tanks and ponds, the urban sewage system is relieved during heavy rain, and water can evaporate. Therefore, the small water circle is closed, and the microclimate is cooled. (Ref. 2; Ref. 6)
The created ponds at Potsdamer Platz
Atelier Dreiseitl
Overview
Nature-based solution
- Blue infrastructure
- Lakes/ponds
- Rivers/streams/canals/estuaries
- Green areas for water management
- Swales and filter strips
- Sustainable urban drainage systems
- Nature on buildings (external)
- Green roofs
Key challenges
- Climate action for adaptation, resilience and mitigation (SDG 13)
- Climate change adaptation
- Environmental quality
- Air quality improvement
- Green space, habitats and biodiversity (SDG 15)
- Green space creation and/or management
- Water management (SDG 6)
- Stormwater and rainfall management and storage
- Improvements to water quality
- Health and well-being (SDG 3)
- Creation of opportunities for recreation
Principal problems in Functional Urban Area (FUA)
- Climate-Related Hazards
- Urban flooding (stormwater)
- Heat stress & Extreme temperatures
- Environmental Degradation
- Biodiversity loss
- Air pollution
- Poor water quality
- Physical water retention and availability
- Land use and Socio-economic change
- Rapid urbanization
- Health, Well-being and Social cohesion
- Inadequate access to recreational opportunities
- Resource Scarcity and Competition
- Water stress (increased demand)
Key priorities
Climate action (adaptation and/or mitigation)
Focus
Creation of new green areas, Creation of green roofs and walls, Creation of semi-natural blue areas, Creation of lakes or ponds, Implementation of green areas for water management (e.g. rain gardens)
Project objectives
To set up natural purification biotopes (Ref. 6).
To provide a sustainable urban drainage system by integrating grey and green infrastructure to relieve the urban sewage system (Ref. 1; Ref. 2).
To reduce rainwater runoff and improve rainwater quality through natural filtration (Ref. 1).
To lower urban temperatures and contribute to a positive microclimate through evaporation and shade provisioning (Ref. 1).
To improve air quality by reducing the concentration of pollutants in densely built urban environments (Ref. 1).
To create waterscapes for recreation and animal habitats (Ref. 1; Ref. 4).
Implementation activities
The rainwater collection system at Potsdamer Platz in Berlin was initiated as part of the redevelopment of the area in the mid-1990s due to the reunification of West and East Germany.
Green roofs on the surrounding buildings collect rainwater which flows into the underground water tanks. Excess water is used inside the buildings for toilets.
Nineteen pumps and two rows of filters are located in the two central water cisterns between the tanks and ponds. The water is also purified and filtered through natural means by constructed wetlands, in the north, main and south waters, encouraging the development of a unique microclimate and increasing the quality of rainwater from surrounding streets that runs into the ponds. (Ref. 6) The underground water tanks can store extra rainwater and ensure a constant water level of the water bodies above ground, while at the same time relieving the urban drainage canals as stored water is fed into them only a few times per year during extensive usage. (Ref. 3; Ref. 6) The ponds created were implemented together with plants that, beyond the filtering function, serve as habitats for species and create an aesthetically pleasing water landscape as a space for relaxation between densely built office buildings. As water binds dust particles, the project furthermore contributes to better air quality in an urban environment. (Ref. 1; Ref. 2; Ref. 6)
Climate-focused activities
Climate change adaptation:
- Increase urban vegetation cover to reduce urban heat island effect
- Implement sustainable urban drainage schemes to manage stormwater
- Other
Main beneficiaries
- Private sector/Corporate/Company
- Citizens or community groups
Governance
Management set-up
- Co-governance with government and non-government actors
Type of initiating organisation
- Local government/municipality
- Private sector/corporate actor/company
Participatory approaches/ community involvement
- Co-planning (e.g. stakeholder workshops, focus groups, participatory mapping)
- Taskforce groups
- Joint implementation (e.g. tree planting)
Details on the roles of the organisations involved in the project
The client of the development project were the city Berlin and the real estate company Debis Immobilien, who are the landowners of the buildings with the green roofs (Debis Immobilien) and the water areas (City). Several architects and landscape architecture offices collaborated with the Technical University Berlin on the realisation of the project, which was financed by the real estate developers as the owners of the buildings that provide the rainwater. (Ref. 3)
Project implemented in response to ...
... an EU policy or strategy?
Unknown
... a national policy or strategy?
Unknown
... a local policy or strategy?
Unknown
Type of enablers
Governance innovations (such as public private partnerships)
Financing
Total cost
More than €4,000,000
Source(s) of funding
- Corporate investment
Type of funding
- Direct funding (grants, subsidies, or self-financed projects by private entities)
Non-financial contribution
Type of non-financial contribution
- Provision of land
Who provided the non-financial contribution?
- Public authorities (e.g. land, utility services)
Impacts and Monitoring
Environmental impacts
- Climate change
- Lowered local temperature
- Achieved lowered local temperature
- Water management and blue areas
- Improved water quality
- Achieved improved water quality
- Increased protection against flooding
- Achieved increased protection against flooding
- Improved stormwater management
- Achieved improved stormwater management
- Green space and habitat
- Increased green space area
- Achieved increased green space area
- Increased number of species present
- Achieved increased number of species present
Economic impacts
- Increased property prices
- Achieved increased property prices
Socio-cultural impacts
- Social justice and cohesion
- Improved access to urban green space
- Achieved improved access to urban green space
- Health and wellbeing
- Gain in activities for recreation and exercise
- Achieved gain in activities for recreation and exercise
Type of reported impacts
Presence of formal monitoring system
Yes
Presence of indicators used in reporting
Yes
Presence of monitoring/ evaluation reports
No evidence in public records
Availability of a web-based monitoring tool
No evidence in public records
Potential risks of implementation and trade-offs
Unknown
References
1.
Ecologic Institute and Sendzimir Foundation (2019). Addressing Climate Change in Cities – Catalogue of Urban Nature-Based Solutions. Accessed on September 12, 2024, [Source link];
2.
Okosvaros (n.d.). Potsdamer Platz - rainwater collection system. Accessed on September 12, 2024, [Source link];
3.
Urban Green-Blue Grids (n.d.). Potsdamer Platz, Berlin, Germany. Accessed on September 12, 2024, [Source link];
4.
Peck, S. W. (2017). Case Study: Potsdamer Platz. p. 17-20 Accessed on September 12, 2024, [Source link];
5.
Zurich University of Applied Sciences (n.d.). Potsdamer Platz, Berlin, Germany. Accessed on September 12, 2024, [Source link];
6.
Greenroofs (n.d.). Potsdamer Platz. Accessed on September 12, 2024, [Source link];
7.
District Office Mitte (n.d.). Einwohner*innen im Bezirk Mitte. Accessed on September 12, 2024, [Source link];
8.
District Office Mitte (n.d.). Demografische und sozioökonomische Daten. Accessed on September 12, 2024, [Source link];
9.
Aktionskreis Energie (n.d.). Dezentrale Regenwasserbewirtschaftung Potsdamer Platz, SEB Asset Management. Accessed on September 12, 2024, [Source link];
View on the Piano Lake
Berliner Wasserbetriebe
Potsdamer Platz, Berlin, Germany
https://urbangreenbluegrids.com/projects/potsdamer-platz-berlin-germany/
Potsdamer Platz, Berlin, Germany
https://urbangreenbluegrids.com/projects/potsdamer-platz-berlin-germany/
Information about this nature-based solution was collected as part of the Naturescapes project funded by the European Union under Grant Agreement No 101084341.