On May 19, 2026, Ofwat announced the winning projects of the sixth Water Breakthrough Challenge, including initiatives on fungal filters, acoustic river monitoring, supercritical waste treatment, and 3D-printed concrete infrastructure.
A £600 million fund over ten years
The funding comes from Ofwat's Water Innovation Fund, which will invest a total of £600 million over ten years in projects and technologies for the environment, society, and customers, according to Thames Water. The competition is run by Challenge Works, part of research foundation Nesta, together with Arup and Isle Utilities.
From fungal filters to river microphones
The Mycofiltration project, led by Anglian Water, receives £1.52 million to test fungal-based filters at stormwater overflows and outfalls. The approach uses mycelium networks to physically retain contaminants while breaking down heavy metals, bacteria, and pesticides, according to H2O Global News. Anglian Water's research and innovation leader Phil Buckingham said the funding would support expansion of natural treatment technologies in the water sector.
The Good Vibrations project, led by Severn Trent Water with partners including SUEZ and the UK Centre for Ecology and Hydrology, will deploy underwater microphones to use artificial intelligence to assess river ecological health through acoustic analysis. Funding for this project is reported at £1.5 million to £1.57 million.
The largest single grant in this round, £9.24 million, goes to Hydrothermal Oxidation, led by Anglian Water. The project will decompose organic waste using water at extreme temperature and pressure without burning it.
Northumbrian Water will receive £1.91 million for Printfrastructure 2.0 to further develop 3D-printed concrete for wastewater infrastructure. The project builds on an earlier pilot that demonstrated CO2 emissions reductions of up to 50 percent and construction cost savings of 8 percent for concrete infrastructure.
In Leicester, a twelve-month pilot called Smoke in the Water, led by Severn Trent Water with Leicester hospitals and other partners and funded at £2 million, will combine artificial intelligence, clinical data, and sewer measurements to identify trends in antibiotic resistance. Researchers cited by industry outlet Kurrant estimate this could reveal such trends weeks earlier than clinical monitoring alone.
In London, the SuDS through Streetworks Market project, involving Thames Water and the Greater London Authority, receives £6.87 million to integrate sustainable drainage systems such as rain gardens into planned street works. Jules Pipe, Deputy Mayor of London, noted that surface water flooding poses a real and growing threat, affecting over 320,000 properties strongly. Thames Water is also piloting through project SI12 whether planned service interruptions for routine pipe maintenance could extend from three to twelve hours to enable renewal techniques within existing pipes and reduce reliance on open-cut work. The three-hour rule currently limits outage time per day but can stretch total maintenance over multiple days and restrict innovative methods. Thames Water will first investigate which service interruptions customers find acceptable, with close monitoring of satisfaction throughout the project. The project is budgeted at £150,000 and is scheduled to complete by the end of January 2030.
Where new methods must still prove themselves
Stormwater overflow pollution has been politically controversial in England and Wales for years, with Ofwat and the Environment Agency tightening enforcement expectations. Biological filter methods like mycofiltration are considered less capital-intensive than conventional grey infrastructure, but field-scale performance data remains limited, making this funded pilot important to clarify. Acoustic river monitoring could also identify ecosystem stress in near-real-time if validated at scale. For biochar from sewage sludge, the same holds: if the process proves effective at removing PFAS and phosphorus, water companies could manufacture their own binding material.
How earlier funding rounds have developed
The current round is not the first. The third Water Breakthrough Challenge produced the Water Net Gain project, which studies how to retain water in ponds and release it during dry periods to rivers or farmland, according to researcher Lucia Grimm of the Westcountry Rivers Trust. An earlier round also produced the Stream project, which, under independent co-lead Melissa Tallack, published near-real-time data on every wastewater overflow in England. Those data are now used extensively for water improvement planning.
Reporting requirements for projects
For the sixth round, each project must submit an initial baseline report by December 31, 2026, with updated goals, timeline, risks, and partners. Projects may request extensions if needed. After that, projects must submit progress reports every six months, or quarterly for high-risk projects, documenting risks, issues, and key lessons. Each project concludes with a publicly available final report reflecting success and lessons learned.