WATER SQUARES
Introduction to a type
The Netherlands has a tradition of discharging rainwater underground via an extensive sewerage system. Despite having a number of visually-prominent canals, the Dutch city has relatively little surface water where the rain can be retained. And the sewerage system already has difficulty coping with the rainwater when it rains heavily. In the coming decades it will not only rain more frequently, the downpours will also be more intense. These peak downpours create problems in the densely-populated urban area: the rainwater cannot drain away because of all the surfaced space. When the sewerage system becomes overloaded the streets become flooded. This flooding leads to difficulties and damage. These large puddles and pools of water are a nuisance, pedestrians cannot keep their feet dry when walking about the city. The flooding causes damage to cellars and houses, shops and catering basements. This is why we are introducing a new type of rainwater storage: the water square.
In order to be able to collect peak downpours (temporarily), areas in the public space are laid out in such a way that the flooding can be regulated. We call these areas water squares. Not a square in the traditional sense of the word, but a square as a central space in a water management collection unit, a collecting basin. Rainwater is collected and retained in this basin. From this basin it can either be gradually infiltrated into the groundwater or finally, at a later point in time, discharged via the existing sewerage system. The water square is dry for the great majority of the time and then it is used like any other public space in the city. After a heavy downpour the form and the use of the water square are transformed. This means that, when designing a water square, the main focus is on its use and recreational value in a dry state. The elements that are necessary for the water storage are, wherever possible, deployed to create an attractive recreational area.