On Water: The colours of water: Green

Taking up the multicoloured nature of the wet element, the colourful opening weekend will focus on three of these colours and their associations: on Friday on rivers (green water), on Saturday on water in the city (purple water) and on Sunday on drought (brown water).

Green water
‘Green water’ is not green at all, but almost invisible. In science, the term refers to naturally occurring soil and rainwater that is absorbed by plants and evaporates again – an invisible cycle that also feeds rivers and keeps their ecosystems alive. It is precisely this invisibility that is the focus of the day: how can the importance of rivers such as the Spree for social and ecological developments be brought more strongly into public awareness? And what changes when a river is regarded not only as a natural space and resource, but also as an independent legal entity?

Programme

13:30–14:00 Uhr: Opening of the exhibition ‘On Water’
Address by Julia von Blumenthal (President of Humboldt University of Berlin)

Introduction by Anna-Lisa Dieter (curator of ‘On Water’)

14:00–15:00: Meet the Scientist – Short lectures on river research

14:00–14:30: Christian Marx: The urban water cycle – where does the water go?

Drought! Flood! Rain! Drought! Headlines like these are becoming increasingly common around the world – and their significance for our lives is growing steadily. Cities and water management are under pressure to mitigate the effects of climate change. That is why we need to understand how urbanisation and climate are affecting the urban water cycle in Berlin.

Together with Christian Marx, we embark on a journey along the Panke, a watercourse in northern Berlin. Where does its water come from? Where does it flow to? And what challenges and opportunities arise for the management of surface water and groundwater?


14:30–15:00: Gerhard Scholtz: Crayfish in Berlin – Of crayfish kings and invasive species

It has been largely forgotten, but for many years in the 19th century, Berlin was the centre of crayfish (noble crayfish) fishing and trade in Europe. Particularly successful traders were popularly known as ‘crayfish kings’. The most respected crayfish king was Friedrich Wilhelm ‘August’ Micha (1826-1883). After completing an apprenticeship as a slipper maker, he entered the crayfish trade at an early age. From 1848 onwards, he ran the ‘A. Micha’ business at Spittelmarkt in the centre of Berlin. He took advantage of the explosive growth of the railway and shipped crayfish all over Europe. The distribution of crayfish thus became an important economic factor in Prussia. From the 1870s onwards, crayfish plague, which originated in America, largely destroyed the noble crayfish population. The crayfish trade collapsed. The introduction of an American crayfish species into the River Oder was intended to save the situation, but led to the further spread of crayfish plague. Today, there are no more noble crayfish in Berlin and the surrounding area. All crayfish living here belong to invasive species and are being combated.


15:00-15:45: The Spree Flows Queer – Art, Design and Our Relationship with Water

Artist talk with Jakob Kukula, Rasa Weber and Daniel Tyradellis

With their artistic works exhibited in ‘On Water,’ designer Rasa Weber and creator Jakob Kukula combine artistic research, ecology, design and river rights: the artificial reef SPREEUQ developed by Weber enables new habitats in rivers and seas, while the Spreeboje created by Kukula amplifies the digital and political voice of the river.

Moderated by Daniel Tyradellis, the conversation explores the possibilities of using artistic and immersive practices to reveal hidden underwater ecologies, expand political discourse and initiate structural change. Can artistic approaches and design help to develop a new relationship with rivers and create a shared environment from the environment? Can design processes be created that focus not on humans but on ecosystems? And can queer ecologies help to renegotiate, beyond classical norms, which life is worth protecting? The dialogue invites the audience to understand water and rivers, as well as their inhabitants, as active co-creators of our society.


15:45–16:15: SPREEUQ – An artificial reef for the River Spree
Workshop with artist Rasa Weber

How is an artificial reef actually created? Designer Rasa Weber explores this question together with visitors to the exhibition ‘On Water’ as part of the participatory workshop ‘SPREEUQ. An artificial reef for the Spree.’ Together, based on traditional craft techniques normally used in fishing, they will work on completing the sculpture, whose twin has been providing a new habitat for the often overlooked, diverse life forms of the Spree at a depth of 2.5 metres in the Spree since May 2025. More at rasaweber.com

Participation in the workshop is free of charge and no registration is required.


17:00-18:00 Uhr: Legalize Spree – The rights of nature in Germany
Panel discussion

A movement recognising rivers, forests and ecosystems as legal entities is growing worldwide. Now this debate is coming to Germany: the first draft law on the rights of the River Spree marks a milestone at the Humboldt Laboratory. But where does the movement stand internationally and nationally? What potential do the rights of nature have for ecological and democratic change in Germany – and what does the Spree need in concrete terms to be protected and strengthened? Together, we will discuss the prospects of this new legal concept, its opportunities for environmental and climate protection, and the question: Is this the beginning of a movement that will fundamentally change our relationship with nature?

With an introduction by Camille de Toledo, Franziska Albrecht (Green Legal Impact e.V.), Tim Edler (Fluss Bad Berlin e.V.), Baro Vicenta Ra Gabbert (Greenpeace e.V.), Carla Reemtsma (Fridays for Future) and Emmanuel Schlichter (Rechte der Natur e.V.).

- free admission
- 14 years and older
- German
- Humboldt Lab, 1st floor
- Belongs to: On Water