«The More, The Merrier»

We're making a rain-powered gravitational fountain flow

For the art in architecture project at the Allmend school complex in Zurich's Manegg district, artist Roland Roos has an idea that is brilliantly simple: a fountain that works with rainwater from the roof without external power. But the realisation has its challenges. We implemented the idea and the finesses it contained on a technical level.

Fountains are in fact a symbol of luxury and waste. Roland Roos' fountain, on the other hand, only runs when it rains. In a humorous and subtle way, he makes us experience our dependence on natural resources and questions our desire to have everything available all the time everywhere.

To reinforce this image, the water jet should be more or less powerful according to the amount of water available. In addition, the fountain should not just splash straight up, but dynamically oscillate.


Structure of the overall system in Simulink

At the start, there was a fundamental question: Will the system work in the first place?
For this purpose, we simulated the entire system consisting of roof, rain water storage tank, pipe and nozzle in various forms and weather scenarios digitally. The results indicate good feasibility: the fountain can reach a height of up to 9m.

The simulation result was validated with rigid nozzle geometries. We then tested different designs of nozzles with variable orifices. The nozzle must not only generate a smooth jet at all water volumes, but also function with low maintenance for decades in all weather conditions.

First tests on a scale of 1:10 to validate the simulation and nozzle geometries
Various approaches for variable nozzles
Mockups for variable nozzles
Testing the nozzle mockups
First variant of a flexible suspension for a dynamic jet
Live tests on site
Simulation results of different rainfall scenarios
This simulation setup allows the calculation of a wide range of scenarios
CAD construction of the nozzle and the articulated suspension

For the realisation of the one-off piece, the components were designed in CAD. The nozzle was manufactured as a 3D printed part from tool steel and precisely ground.
After assembly and some optimisations, the fountain was put into operation in March 2023.

Market launch:


Our Contribution:

System modelling
Implementation support

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