Dutch water authorities (waterschappen) recover valuable secondary materials during wastewater treatment but face legal restrictions on commercializing them. To bridge this gap, the Friesland water board Wetterskip Fryslân cooperated with the Energy and Raw Materials Factory, research foundation STOWA, and the company KNN Cellulose (now Recell Group) within the "Van afval naar asfalt" (VANA) consortium. This partnership aimed to close the circular loop by establishing a commercial value chain for cellulose recovered from sewage water.
Every year, the Netherlands flushes around 180,000 tonnes of toilet paper down the drain. Conventionally, this cellulose is treated as waste and incinerated at high cost. By extracting the fibers early in the treatment process, water boards not only reduce the energy required for sewage sludge decomposition but also recover a high-quality plant polymer that can replace raw materials like virgin wood or mined minerals.
On 15 September 2016, the consortium opened a one-kilometer cycle path between Leeuwarden and Stiens, marking the first road in the world to be surfaced with asphalt using cellulose recovered from toilet paper. The fibers act as a drip inhibitor, preventing the bitumen from separating out of the stone-and-sand mixture. Following this pilot, the technology was scaled up by the joint venture Cellvation, which processed over 15,000 tonnes of cellulose from wastewater by early 2025 for use in major infrastructure projects across the Netherlands.
The project offers key insights for countries like Switzerland, where phosphorus recovery from sewage sludge becomes compulsory in 2026. Like their Dutch counterparts, Swiss wastewater treatment plants will become holders of secondary raw materials without commercial distribution networks. The Dutch model demonstrates that creating specialized intermediaries and public-private consortia is essential to transform public resource recovery into a viable market.