Could Sewage Sludge Solve the PFAS Problem?

Severn Trent leads a £1.6m Ofwat-backed team turning pyrolysed sludge into a circular medium for PFAS and phosphorus removal

2 Jun 2026

Sewage sludge is not a glamorous feedstock. Yet a £1.6m grant from Ofwat's Water Breakthrough Challenge, awarded in May 2026, is backing precisely that premise. Severn Trent Water leads a consortium including Nijhuis Saur Industries, Harper Adams University, the University of Exeter, and Shropshire County Council. Their goal: convert pyrolysed sludge into biochar, a carbon-rich material capable of removing both PFAS compounds and phosphorus from wastewater.

The timing is not coincidental. Binding EU limits on PFAS took effect in January 2026 under the revised Drinking Water Directive. Conventional treatment technologies adsorb contaminants but do not destroy them, leaving secondary waste that still requires disposal. Biochar, produced by heating sludge at high temperatures, can be modified to trap multiple pollutants at once. One waste stream, two compliance headaches addressed.

Phosphorus matters here too. Excess phosphorus is a leading cause of algae blooms in European freshwater systems, so targeting it alongside PFAS sharpens the case for the approach rather than diluting it. The circularity is the point: a regulated waste product becomes the treatment medium, not just the problem.

Field trials across varied wastewater chemistries must still confirm that performance holds at scale. The consortium's funding sits within a wider £58m package distributed to 19 projects, itself part of Ofwat's decade-long £600m Water Innovation Fund. Each award requires collaboration between utilities, universities, and industry partners, a structural bet on distributed expertise over single-institution research.

Whether biochar proves reliable within the compliance windows that EU law now sets is an open question. What the Severn Trent consortium demonstrates is something less dramatic but more durable: a model in which contaminated waste becomes a resource, multi-institution knowledge drives development, and circular outcomes define success. That is a replicable template for a sector that has very little time to find one.