Since a cloudburst in 2011, when the rainwater flooded the basements on Eriks Ballings Vej 4, local residents explored the possibilities for establishing rainwater gardens in their styreet. The residents chose to join forces and and enter into a collaboration with the City of Copenhagen and HOFOR. The outcome was a road renovation project that established three rainwater gardens on Eriks Ballings Vej.
The rainwater gardens were inaugurated on June 28, 2018.
When rain falls on the roof of the houses in Eriks Ballings Vej 4, the water from rain gutters will be discharged directly into the rain gardens. About one thrid of the rain water thereby is diverted away form the sewer sytem. This increases system capacity and prevents overflows or back flows. The soil in the rain gardens is able to filter pollutants that may be carried with the rainwater. The waer is thereby purified before it infiltrates into the groundwater.
Rain gardens can have many different designs and functional concepts and applications. This meant that each rain garden has to be adapted to its specific environment and use. Volume and water quality, as well as the soil type in which they are embedded, are important parameters. It is therefore crucial to investigate these conditions, and to apply for the necessary permits (e.g. for ground water infiltration), before the gardens are built – on public as well as on private land.
Rainwater beds have the potential be a beautiful and creative method to handle rainwater in a sustainable way. There is a wide selection of plants that can withstand the fluctuating amounts of water, and the beds can thus be customized according to the wishes of the respective stakeholders.
This project was created as a partnership between The City of Copenhagen and HOFOR – Greater Copenhagen Utility.
