On Water: Die Farben des Wassers: Grün

On the opening weekend of the "On Water" exhibition from 10 to 12 October 2025, everything revolves around the "Colors of Water". Even though water often appears blue, it occurs in nature in very different shades - such as gray, black or red. Many of these colors have meanings, some of them serve as technical and scientific designations.

Taking up the multicolored nature of the wet element, the colorful opening weekend will focus on three of these colors and their associations: on Friday on rivers (green water), on Saturday on water in the city (violet water) and on Sunday on dryness (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 evaporated 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 into the public eye? And what changes when a river is seen not only as a natural space and resource, but also as a legal entity in its own right?

Program of the day

13:30-14:00: Opening of the exhibition "On Water"

Speech by Julia von Blumenthal (President of Humboldt-Universität zu Berlin)Introduction by Anna-Lisa Dieter (Curator "On Water")

14:00-15:00: Meet the Scientist - short presentations on river research

14:00-14:30: Christian Marx: The urban water cycle - Which path does water take?

Drought! Flood! Rain! Drought! We come across headlines like these more and more frequently around the world - and their significance for our lives is constantly growing. Cities and water management are under pressure to mitigate the consequences of climate change. That's why we need to understand how urbanization and climate influence the urban water cycle in Berlin.

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

14:30-15:00: Gerhard Scholtz: Crayfish in Berlin - of crayfish kings and invasive species

It is largely forgotten, but for many years in the 19th century Berlin was the center for catching and trading crayfish (crayfish) in Europe. Particularly successful traders were popularly known as "crayfish kings". The most respected crayfish king was Friedrich Wilhelm "August" Micha (1826-1883). After an apprenticeship as a slipper maker, he entered the crab trade at an early age. From 1848, he ran the "A. Micha" store on Spittelmarkt in the center of Berlin. He took advantage of the explosive development of the railroad and shipped crayfish all over Europe. The sale of crayfish thus became an important economic factor in Prussia. From the 1870s onwards, the crayfish plague from America largely destroyed the crayfish stocks. The crayfish trade collapsed. The release of an American crayfish species on the Oder was intended to save the situation, but led to the further spread of the crayfish plague. Today there are no more 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 to water

Artist talk with Jakob Kukula, Rasa Weber and Daniel TyradellisWith their artistic works exhibited in "On Water", designer Rasa Weber and designer Jakob Kukula combine artistic research, ecology, design and river rights: The artificial reef SPREEUQ developed by Weber enables new habitats in rivers and seas, the Spreeboje created by Kukula amplifies the digital and political voice of the river.The conversation, moderated by Daniel Tyradellis, explores the possibilities of using artistic and immersive practices to make hidden underwater ecologies visible, expand political discourses and initiate structural change. Can artistic approaches and design be used to develop a new relationship to rivers and create a co-world from the environment? Can design processes be created that focus on ecosystems rather than people? And can queer ecologies help to renegotiate which life is worth protecting beyond classical norms? The dialog invites the audience to understand water and rivers and their inhabitants as active co-creators of our society.

15:45-16:15: SPREEUQ - An artificial reef for the Spree

Workshop with the artist Rasa Weber

How is an artificial reef actually created? Designer Rasa Weber asks this question together with visitors to the "On Water" exhibition as part of the participatory workshop "SPREEUQ. An artificial reef for the Spree." Based on traditional craft techniques normally used in the fishing trade, they are working together to complete 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 meters since May 2025. More at rasaweber.com

Participation in the workshop is free of charge and does not require registration.

17:00-18:00: Legalize Spree - The rights of nature in Germany

Panel discussion

A movement is growing worldwide that recognizes rivers, forests and ecosystems as legal subjects. Now this debate is coming to Germany: a milestone is being set in the Humboldt Labor with the first draft law for the rights of the Spree. 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 actually need in order to be protected and strengthened? Together we will discuss the perspectives of this new legal idea, 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 and 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 of charge

- from 14 years

- Language: German

- Humboldt Lab, 1st floor

- Belongs to: On Water