Trials of a simple yet innovative approach to reducing toilet flushing show that switching to less frequent flushes can lead to significant water savings and lower bills.

A simple odour neutraliser in the form of a pellet dropped into the toilet bowl after urination could save hundreds of thousands of litres of water every year and money off bills if the results of trials with two UK water companies are scaled up.

Wizso pellets, produced by a Belfast-based company of the same name, are made from non-toxic substances and can be dropped into the toilet bowl in place of flushing urine. Use of the tiny pellet, which changes toilet water to blue and eliminates odours, gives users the confidence not to flush and the opportunity to save water and money on household bills.

Water stress is becoming increasingly common, and the UK’s Environment Agency confirms that England faces a 5 billion litre/day shortfall for household water supplies by 2055. Toilet flushing accounts for a huge volume of clean water usage in the UK, with an average flush volume of 7.5 litres. Each person urinates around seven times a day, equating to a personal usage of more than 50 litres just to flush the toilet.

While savings on one flush may not seem significant, using Wizso to help people make one small change every day, across thousands of households and workplaces, could make a massive difference to the availability of water resources and the health of the environment, while reducing household water bills in the process.

Water saving potential

Wizso’s first customer trial in September 2024 was undertaken with UK water company Affinity Water in a new 908 housing development in Bidwell West, Bedfordshire, to test the impact of a behaviour change only campaign, with no technological interventions, to try an undo the water footprint of building the development.

Affinity’s final report - Creating a water-neutral development using behaviour change and off-setting - included an initial assessment of the impact and feasibility of various water-saving actions, which was carried out before the trial.

Modelling identified Wizso as having the highest potential for water-saving, based on considerations like expected volumes saved and customer-readiness to adopt. This was assessed as over a third more than using half-flush toilet buttons, and nearly three times as much as turning the tap off during teeth-brushing.

Results after the trial showed that participants who experienced the combination of doorstep conversations, a water-saving pledge, and adopting Wizso, saved an average of 51.1 litres of water daily.

In comparison, those who only took a pledge saved 32.9 litres per day, while households that received water saving information only managed to save 17 litres per day.

Positive results

Lina Nieto, Affinity Water’s then water neutrality manager, said, “Bidwell Water Savers was a trial to test the impact of a behavioural change campaign on water usage.

“The results have been very positive, and we were delighted to offer Wizso to participants who pledged to reduce their water usage. We have used Wizso in previous research projects and are excited to see its water-saving potential continue to develop.”

According to Affinity Water, nearly 60% of participants accepted Wizso to trial and were “intrigued by its innovative potential”, while 72% are likely to use the product again or recommend it to others.

The report highlighted the finding that distributing Wizso during the door-knocking campaign significantly boosted water-saving efforts, making these participants the most successful water-savers in the trial.

Water-saving behaviour-change specialist Weir the Agency provided strategic support to the Bidwell initiative and co-founder Jane Bellard said, “Wizso was really positively received by customers taking part in Bidwell Water Savers.

“Those households who used Wiszo saw significantly higher savings than those who didn’t. People were pleased they didn’t have to flush or use chemical cleaners in their toilets as often.”

Workplace use

More recently, Scottish Water undertook a workplace trial and deployed Wizso and Aguardio flush sensors in four toilets at the public utility’s Inverness office for eight weeks. The site has approximately 30 employees and four cubicle toilets.

This trial successfully demonstrated that Wizso enabled an average 27% reduction in flushes over four weeks, representing a possible annual water-saving of some 2,300 litres for this small office.

The trial also identified Wizso as a great way to encourage positive behavioural changes toward water usage and raise awareness around water demand management.

Other ongoing trials with Wizso include workplaces, housing developments and student accommodation blocks.

Mark Gilligan, director of Wizso, said, “We are delighted that our water company trials have already delivered such positive results. Wizso is a great innovation that will drive long-term water savings for consumers and businesses alike.

“With further controlled trials, ongoing development of the product, and enhancements to the user experience, we are gathering more robust data on the exact savings Wizso can be expected to deliver on carbon and cost, along with the product’s full water-saving potential.

“Wiszo is receiving significant interest from across the global water sector, along with hospitality, commercial buildings, facilities management, and personal care brands. With applications across many markets, we are very open to building more relationships.”