In partnership with Sustainable Urban Delta Foundation (SUD)

The Netherlands’ largest rooftop farm includes a sensor-controlled roof—with 24/7 connection to the weather forecast and a much larger water storage capacity than regular green roofs—providing for the farm and retaining excess floodwater during peak storms.
THE SMARTEST ROOF in THE NETHERLANDS can help prevent flooding
The SlimDak (or Smart-roof) on the roof-pavilion of the Schieblock in Rotterdam, the Netherlands, is an intelligent water storage green-roof with a smart-flow control that is driven by the weather forecast. When predicting extreme rainfall, the smart-flow control responds by making extra water storage capacity available up to 24 hours in advance.

The Slimdak on top of the central pavilion is a clever water storing rooftop with smartflowcontrol that is controlled by the weather forecast. When extreme rain is predicted, the smartflower control reacts by making extra water storage capacity available 24 hours in advance. Source: Sanne van Hemert for BrightVibes
There is a phone card in the roof that constantly calls with the weather forecast
The RIVM (Netherlands’ National Institute for Public Health and the Environment) has calculated that it can be 6-8°C (39-46.5°F) warmer in Rotterdam city centre compared with the countryside outside the city.
Those are huge differences. In addition, you need climate adaptation to solve the water problem in the city. In Rotterdam [the Netherlands] there is a real problem with water.
Up on the Dakakker, they have built a smart roof that is completely automatic, with a 24-hour all day connection with the weather forecast. There is a phone card in the roof that constantly calls with the weather forecast.
When the weather forecast says: “it will stay dry.” then he lets the water sit, if the weather forecast says: “a very big storm is coming.” and the roof is full of water, then it will slowly release the water to the city sewer, 12 hours in advance. Not a sudden splash, but very slowly to the sewer. Then the roof is already empty or half empty when that rain comes, and there is room for new rainwater.

Source: Sanne van Hemert for BrightVibes
This idea scales up
This is only a very small rooftop around 120 square metres. Can you imagine that there are 4,000 square metres or an entire neighbourhood with this system? That has an effect, because then you can store water well. You can use the water for your greywater systems in your buildings. The sewage system does not need to be as large. It is all less because you collect the water on the roof.

On the rest of the Dakakker they can collect about 60 litres per square metre of rainwater. On the smart roof they can double that amount 120 square metres. That is the SlimDak system, which is fully automatically controlled. Source: Sanne van Hemert for BrightVibes







SUSTAINABLE URBAN DELTA: INSPIRING AND EMPOWERING CITIES TO BECOME FOOD PRODUCING COMMUNITIES
The Sustainable Urban Delta Foundation was established to inspire megacities to make choices that open the door to healthy and sustainable urban growth. A crucial element of our approach is the production of local, healthy and fresh food. This can either be done inside cities or on undeveloped agricultural land surrounding cities, known as green belts. We aim to be the catalyst and the connector in order to create a better future. Learn more.