Smart use of rainwater leads to significant drinking water savings in the waterfront district
In the Waterfront district in Harderwijk, Joosten JustNimbus, – part of the Joosten Group – demonstrates how large-scale rainwater systems can contribute to circular water use. The municipality set a clear requirement: a minimum of 30% reduction in drinking water consumption. The result speaks for itself.
With the delivery of 163 rainwater systems – providing a combined storage capacity of 529,000 litres – residents can use rainwater for toilet flushing, washing machines, and garden irrigation. This significantly reduces drinking water consumption while also buffering rainwater locally during heavy downpours.
Total expected annual savings: more than 5.2 million litres of drinking water.
Rainwater as a serious resource
“This project is a textbook example of how we can normalize rainwater as a full-fledged alternative to drinking water for suitable applications,” says Iwan Fransen, inventor of the JustNimbus system. “By applying these systems at both large and small scales, we can truly make an impact.”
The technology is here. Now it’s about sharing this knowledge and scaling up its implementation.
Knowledge as a lever
During a recent presentation to municipal representatives and water authorities, Joshua Nahafahik (consultant for innovation, sustainability, and advisory at Joosten Group) and Darryll Braaf (project sales manager at Joosten JustNimbus) emphasized that rainwater harvesting is not a luxury — it’s a necessity.
Waterfront Harderwijk proves that sustainable water solutions at the district level are both realistic and achievable. The project aligns seamlessly with the vision of Water Alliance: contributing to the global transition toward a circular water chain, where technology is the key to structural solutions.
Want to learn more about this project or join the Water Alliance Circular Water Expert Group? Feel free to contact us. Together, we accelerate the shift toward sustainable water technology.
