Separating rainwater from wastewater in urban areas

Sewer separation projects are often conducted by establishing separate piping systems for rainwater and wastewater. In the neighbourhood of Risvangen and Vorrevangen in the city of Aarhus, however, no rainwater pipes are dug down.

Instead, all rainwater is handled on the surface using various sustainable drainage system (SUDS) elements. The local citizens can either choose to handle rainwater on their own plots and in return receive a financial reimbursement of the connection costs, or lead the water to a nearby public area via the surface, where Aarhus Vand handles it.

Getting the citizens on board was a difficult, yet crucial task. While some homeowners embraced the new recreational solutions, the project was also met with some resistance from more sceptical citizens.

The project team therefore had to be very thorough and convincing in their approach, and extensive efforts were made to ensure that the process of involving the citizens was steered in the right direction. A combination of workshops, extensive FAQ’s and even individual advisory sessions on private plots were conducted to ensure a successful implementation.