New green infrastructure separates rainwater and wastewater in Aarhus, Denmark

Key Learnings

• Separation of storm- and wastewater: Separating sewers reduces the risk of urban flooding during stormwater events, especially for local depressions and basements. It greatly improves water quality in streams and coastal areas, and the system is adapted for future challenges, making it more resilient and creating opportunities to integrate Nature-based Solutions.
• Sustainable urban water management with additional benefits: Nature-based solutions for climate adaptation can also enhance local recreation. Realising this potential requires intentional design to make new green spaces welcoming and usable for residents.
• Collaborations support project success: Close cooperation between the city and the water utility company, with transparent agreements on processes and economy, contributed to project success.

Summary

The climate adaptation project in Risvangen serves as a demonstration site for alternative approaches to managing excess water – the area’s most pressing climate-related challenge. By separating rainwater from wastewater and implementing nature-based, terrain-focused solutions, the project both reduces water pollution and prepares the neighbourhood for future stormwater events. This new approach to climate adaptation in a residential setting ensures dry basements while creating a greener, more liveable environment with enhanced recreational spaces. The project also acted as a pilot for engaging local residents in large-scale, integrated initiatives, highlighting valuable lessons and promising opportunities for future efforts.

Contact

Name: Mathias Joachim Skov Pristed or Lone Telling

Organisation: City of Aarhus, Denmark

E-Mail: pmajoaarhus [dot] dk (pmajo[at]aarhus[dot]dk); tnlaarhus [dot] dk (tnl[at]aarhus[dot]dk)