A square that catches rainwater when it rains

Rain fills the sunken court where people play basketball. At Benthemplein in Rotterdam, the Netherlands, that is part of the design. In dry weather the square is a place to run, sit, and rest; in rain it temporarily receives runoff from the surrounding area. Water storage shares a space with public life instead of remaining hidden underground.

Design practice De Urbanisten calls it a watersquare. Completed in 2013, it has three basins at different depths: two shallow and one deeper. The shallow pair receive runoff from their immediate surroundings when it rains. The deep basin takes water from a wider area during sustained rainfall.

Large stainless-steel channels remain visible across the pavement. They carry water into the basins. Areas that can fill with water are blue; routes that carry it are shiny metal. Even on a dry day, the lines and colors suggest where the water will travel and collect. Rainwater movement becomes a visible part of the square.

When dry, the same basins become places for activity. Lower surfaces and surrounding steps separate participants from spectators. The designers describe the deepest basin as both a sports court and a theater for seeing and being seen. Its recessed shape accommodates water in rain and people sitting around its edges in fair weather.

The square also makes room for planting. Existing large trees were retained, with tall grasses and flowers helping divide the space. Open areas for movement sit alongside quieter places to pause. The layout considers daily users as well as the route water will take.

The designers developed its uses with local people. Students and teachers, representatives of a church, youth theater and sports facility, and neighborhood residents joined three workshops. They discussed activities, atmosphere, and how rainwater should appear as it crossed the square. The design record describes a wish for both generous places for young people to play and smaller green spaces.

The basins temporarily hold rainwater; one square does not solve every flooding problem in a city. What the project does is give everyday uses to land that might otherwise wait empty for rain. Once the surface dries, a ball can bounce there again while people watch from the steps.

Image description: Preview of an interview from the official Rotterdam Climate Initiative video about the opening of Benthemplein.
Image source: Rotterdam Climate Initiative RCI / Official release video preview
https://www.youtube.com/watch?v=MH1lMzkad1w
Image changes: resized with the original aspect ratio preserved and converted to WebP. No cropping.