On Friday evening Roof Water Farm came to Little Wood. Everyone was excited – little farm meets Little Wood – and it turned into something special. You couldn’t tell if it was a lecture or a picnic. People sat on Kerim Seiler‘s colorful sculpture and drank, ate, took notes, or simply listened as the sun set.
Dr. Anja Steglich and Grit Bürgow of Technische Universität Berlin, farmers by trade, came to share their project with us. Let’s hone in on that a bit. Roof Water Farm is what is promises at first glance: a rooftop farm that has something to do with water, and much more.
The farm’s history goes back to 1987 when an IBA social housing project in Kreuzberg was fitted with water infrastructure that treated gray water (waste water from showers and sinks) and circulated it back into the housing complex for re-use. Ms. Bürgow and Dr. Steglich now tied these thoughts into the existing structure of housing block 6. The questions they posed themselves were: How can one close water circulation systems in buildings? And how can urban water infrastructure be more flexibly designed?
In the beginning it was all about the water, after all: The average city dweller uses approx. 100 liters of water a day. From that only 6-8 are for dietary purposes. That means 82 liters don’t need to be potable in quality, but merely bathing water quality; to this effect, these could easily come from gray water. The thought of the water cycle dovetailed relatively quickly with the idea of the food cycle. And that’s how agriculture, or aquaponics, ended up in the project.
Aquaponics is a system in which plants grow without soil. Their roots are in direct contact with water. Swimming in said water are fish that provide the plants with nutrients via their excrement. Nothing new here – the Chinese started putting fish in their rice fields 4,000 years ago because they realized it grew so much better. Ms. Bürgow and Dr. Steglich put their fish in greenhouses filled with bath water, better in quality than most rivers these days. They’re currently growing strawberries.
That’s how the first Roof Water Farm came to be, a project straddling architecture, landscaping, agriculture, fishing and urban planning. And new doors just keep opening. “We would have never thought it would be so beautiful.” The scientist’s eyes sparkle when she talks about her vision of a green city where all rooftops are furnished with little greenhouses. This would be beneficial for both the environment and society. Neighbors would come together on rooftops, could spend evenings in their greenhouses and enjoy the view.
Currently Dr. Steglich and Ms. Bürgow are working on developing prototypes, district prototypes, that is, to illustrate how a Roof Water Farm system could work at the municipal level. For more information, you can visit their website, but visiting block 6 in Kreuzberg is much richer.
Text (DE): Theresa Patzschke
Images: Marc Brinkmeier