The Flush Forward Challenge launched on 5 October 2026 to accelerate market-ready sanitation technologies and help advance progress towards safe sanitation for all.
The Flush Forward Challenge is delivered by Challenge Works, in partnership with Bluechain Consulting and Cranfield University and is funded by the Gates Foundation.
What sanitation challenges is the UK facing?
The UK continues to rely on a sanitation model developed for a different era: using treated drinking water to flush waste into septic tanks and centralised sewer networks.
Every flush puts additional pressure on this infrastructure, contributing to the release of harmful nutrients or sewage overflows that affect rivers and bathing waters and require billions in reactive repairs.
At the same time, the assumption that water is an abundant resource is increasingly being challenged. Existing sanitation infrastructure is also connected to constraints on development, with nutrient neutrality regulations protecting river health while limiting housebuilding in areas where existing systems cannot handle the additional load.
The Flush Forward Challenge aims to reopen the conversation about how water and sanitation are managed, moving from sanitation as a passive infrastructure burden towards a more dynamic and circular approach.
What is the Flush Forward Challenge?
The Challenge is aiming to build a deeper and more complete picture of issues across the UK caused by non-sewered sanitation problems, and to understand if Reinvented Toilet technologies could be a potential solution to overcome these.
The Challenge is calling on local “problem owners”, such as rivers trusts, local councils, New Appointment and Variations (NAVs) operators and eco-charities, who already directly deal with the impact of these social and environmental issues in their region, to delve into analysis in their region o understand the issues more deeply, and develop a vision including potential solutions.
What are reinvented toilet technologies?
Reinvented toilet technologies are non-sewered sanitation systems that are designed to: remove pathogens and environmental contaminants, regenerate water, and operate fully off-grid without sewer systems or piped water. Through the Reinvent the Toilet Challenge, the Gates Foundation and its partners have developed over 25 breakthrough processing components and technologies, with solutions in use in communities around the world.
Despite the name, these technologies typically focus on the treatment of toilet waste, rather than the toilet you actually use. These technologies range from a compact waste treatment in a single bathroom toilet to a waste processing system that replaces the septic tank.
Some of these technologies, also known as “non-sewered sanitation systems,” have many benefits versus those currently available on the market. These benefits, encapsulated in ISO 30500, include high nitrogen and phosphorus recovery with pathogen-free outputs.
Who will be involved in the Flush Forward Challenge?
The Challenge is calling on organisations such as river trusts, local councils, New Appointment and Variations (NAVs) operators, and eco-charities to take centre stage as local “problem owners”.
These organisations have direct knowledge of local sanitation pressures, including agricultural runoff, nutrient neutrality, pressures on waterways, development constraints and communities affected by failing infrastructure. They will be conveners who have the ability to bring together local stakeholders in their regions, to tackle issues impacting their communities.
How could decentralised sanitation address local challenges?
Decentralised, off-grid technologies, such as Reinvented Toilet technologies, can operate without relying on connections to the main sewer network or piped water.
Within the Flush Forward Challenge, local organisations will explore how these technologies could respond to specific regional challenges, such as tackling nutrient neutrality in sensitive catchments or reducing mains water demand in water-stressed municipalities, with the potential to unblock stalled house-building and improve the health of our waterways.