Blue City Circular Water is the first ever innovative water solution in the city of Rotterdam maximizing the reuse of (waste)water in residential and commercial buildings and recovering green fertilizers and reducing fresh water consumption. The revolutionary installation, called Blue City Circular Water, turns rainwater from the rooftop and grey water into water to flush toilets and simultaneously treats the wastewater of the building, recovering its nutrients. In this partnership, Nijhuis Saur Industries together with Semilla Sanitation, Blue City, Hoogheemraad Schieland & Krimpenerwaard and Waterschap Hollandse Delta, water is treated in a smarter and more sustainable way building resilience against water scarcity.
Managing water scarcity and drinking water availability
On average, a Dutch household uses approximately 129 liters of drinking water per person per day*. This high-quality water is often used for laundry and to flush toilets. Society must find better and smarter ways to protect the precious drinking water needed for human consumption. It is inevitable that - with climate change, increased pollution of natural water resources, and a growing population - access to fresh drink water is already becoming a serious challenge. Without immediate action, a serious water shortage is a very real threat for a country like the Netherlands in the years to come.
Blue City Circular Water Rotterdam
In the basement of Blue City a circular model is created. Toilets, unisex urinals, and showers have been installed to collect the various sanitary water flows separately. With the launch of this installation, a fully integrated and safe water treatment concept for the entire building is created, efficiently reusing water and extracting valuable nutrients such as compost and fertilizers.This project is not only piloting the technical feasibility but also the economic feasibility at full scale. The sanitary system, based on space technology, uses water collected from rainwater and from the sinks and showers (grey water), urine from the urinals (yellow water) and water from the flushed toilets (black water). The wastewater is purified to be reused as irrigation water to grow plants in and outside the building. This creates a circular water stream without any waste. Green fertilizers are extracted from the yellow water, and compost and fertilizer from the black water. This installation delivers a decentralized circular solution and closes the wastewater and food loop, delivering three of the necessities for life: sustainable water, food, and safe sanitation.
Royal visit to Blue City
On Tuesday, October 17, her Majesty Queen Maxima visited Blue City to meet the circular entrepreneurs and discuss the possibilities of scaling up circular initiatives. During the tour around Blue City Circular Water, the participants highlighted the importance of cooperation and innovation and the positive ecological impact of the closed-loop concept to give water the value it deserves and contribute to a more sustainable and resilient future.
Menno M. Holterman, CEO and president of Nijhuis Saur Industries:
"The decentralized treatment of water in a circular way in residential and commercial buildings is not yet common practice. In partnership with all relevant stakeholders and Semilla Sanitation, part of our scale-up accelerator program, we gained extensive know-how and experience to design, build, operate and maintain the best water-on-demand solutions for the reuse of water in residential and commercial buildings. With all the water challenges we face globally, we need to explore, accelerate, and adapt game-changing innovations to close the water loop and give water the value it deserves. We call it #MissionWater."
