In a city with an immense building rate such as Istanbul, the capacity of the soil to absorb rainwater has been consistently diminished for the past few decades. Coupled with the changes in the climate that brings heavy rainfall, flooding has become an issue that afflicts many different neighborhoods. The Palais de Hollande in Istanbul is becoming increasingly exposed to the whims of the elements, swinging between floods or water shortage in periods of drought. For centuries, Dutch creativity in terms of water management has inspired and informed others. In January 2019, 26 people from Turkey and the Netherlands came together in a co-design session to generate ideas and designs about a possible system that could do just what the initial question asked: To reuse rainwater sustainably and efficiently.