With the help of an ingenious computer system, the Decision Support System (DSS), the blue-green RESILIO roofs can respond to the weather forecasts. This system determines how much water can, may or must be retained on a roof. The Decision Support System is built and managed by Waternet – the Dutch Public Water Authority – and signals out to the blue-green roofs.
How does this work? Well, when heavy rainfall is expected, the DSS signals the smart valve on the blue-green roof to discharge the retained rainwater before the expected downfall actually happens. In this way, a smart roof can collect the maximum amount of rainwater during a shower. And less pressure is put on the sewage. During dry periods that same water obtained on the roof is not only cooling down the building, but the roof decreases the temperature in the surroundings as well, and the roof is watering her own greenery. It’s an Einstein roof!
Micro and macro factors
The Decision Support System collects and saves data. This information can be divided into micro and macro factors. An example of a macro factor is groundwater level. If the groundwater level is low, we can discharge water from the roof if there is enough. In this way the groundwater is being replenished and the water level rises.
Around a flooding stress area, for example a lower point in the city like the Oosterpark in Amsterdam, we have a potential risk of flood so we want to retain the rainwater on the roof to avoid streets and sewages being overflood. Macro factors such as seasons and geographical location also influence the control of the smart valve. Close to a hospital, it is of paramount importance the accessibility is always guaranteed so water on the road must be prevented here.
Micro factors are elements related to the specific blue-green roof. The water storage capacity is an example. Or, and we are still exploring this possibility, the amount of water that a household needs for different purposes, like flushing the toilet. The DSS can take all these factors into account. So the roof is a tailor-made Einstein!