The Noorderhoek neighbourhood in Sneek, Friesland, is the first of its kind to implement decentralised wastewater treatment, reducing reliance on centralised systems and lowering drinking water consumption. This approach enables more sustainable water use, supports nutrient recovery, and contributes to CO2 emission reductions by minimising energy-intensive water treatment processes. The project was instrumental in the development of DeSaH, a company that has since scaled this water technology internationally. The success of this initiative is closely linked to Friesland’s water technology ecosystem, particularly WaterCampus, which played a critical role in advancing research, innovation, and business development in circular water solutions.

Noorderhoek’s decentralised wastewater treatment system demonstrates how circular water management can be successfully implemented in urban settings. By fostering collaboration between research institutions and businesses, Friesland continues to lead in water technology innovation, providing a replicable model for sustainable urban water solutions.

Traditional wastewater management relies on centralised treatment systems, which are energy-intensive and inefficient at nutrient recovery. Toilet water, which constitutes only 1% of daily wastewater but contains over 90% of all pollutants, is mixed with greywater, making resource recovery more challenging. The existing approach leads to high energy consumption, water wastage, and the loss of valuable nutrients, which could otherwise be returned to agricultural systems. The need for a more efficient, decentralised solution was evident, particularly in urban developments aiming for circular water management.

Noorderhoek implemented an innovative decentralised wastewater treatment system. The approach included vacuum toilets, which significantly reduce water use and keep black water separate from greywater, enabling easier nutrient recovery. The concentrated black water undergoes an advanced treatment process that extracts nutrients and generates clean water suitable for reuse. Greywater from showers, sinks, and washing machines is treated separately, producing relatively clean water for reuse. The system is energy-efficient, reducing the energy required for wastewater treatment and lowering CO2 emissions.

This initiative led to the founding of DeSaH, a company that emerged from testing this technology in Friesland. DeSaH has since scaled the model internationally, including in Sweden, and is working on new projects in Leeuwarden to develop housing that is entirely off the water grid.

The Noorderhoek project has demonstrated the feasibility and benefits of decentralised wastewater treatment, leading to several key impacts. By separating black and greywater streams, overall drinking water demand is significantly reduced. The system enables the extraction and reuse of valuable nutrients from human waste, supporting sustainable agriculture. Energy savings from the decentralised system contribute to lower CO2 emissions compared to traditional wastewater treatment methods. The technology, developed and tested in Noorderhoek, has been successfully applied internationally, with further implementation in Leeuwarden to develop off-grid water solutions. Additionally, the initiative highlights Friesland’s leadership in water technology and the role of WaterCampus in fostering circular innovations by connecting research institutions and businesses.

This project exemplifies the Frisian way of integrating research, innovation, and business in the circular transition. WaterCampus played a crucial role in enabling the success of DeSaH by supporting the development and scaling of the technology. Noorderhoek serves as a model for other urban developments seeking sustainable water management solutions.