Introducing the Carbon Initiative with IWA Water Loss Specialist Group
Published on: 12 Feb 2025
Read moreWhile the industry has made the national press with the plight of the 'leaky loo', a backlash on all water efficiency measures could arise if we get the message wrong. The water sector needs to work together and find ways to move forward, to keep user acceptance of water efficiency measures high by building confidence in user-friendly and desirable products.
So it has been a very interesting day, seeing BBC news headlines relating to 'Leaky Loos' after over a decade of work drawing attention to the topic. I whole-heartedly agree, leaky loos are a terrible problem and if we could fix them we would undoubtedly save a huge volume of water every day. But this terrible tale of toilets has a twist, and if you can spare me a few minutes I'd like to explain why.
Historically toilet flush cisterns would hold up to around 16 litres of water - often mounted high - to allow water to come gushing down and flushing our waste away. The graphs below, taken from some micro-component, or end-use studies a few years back show how, at the time, homes built after 2001 (when the Water Supply (Water Fitting) Regulations changed) typically used less water for toilet flushing per-flush than older homes.
Indeed, research by my colleagues and I showed that the proportion of daily water use for toilets dropped from around 30% of daily household use, to 20%. This was driven both by the lower cistern volumes, and the use of the 'part flush' button.
Alongside this change came, however, a whole pile of confusing situations. For dual flush toilets with push buttons - sometimes you pressed the big button for a full flush, sometimes for the part flush. Labelling is still unclear to this day. And sometimes, despite the installation of the toilet, a facilities manager might over-ride common sense with advice for users. It never fails to amaze me how many times I come across stickers that read: "Please push and hold both buttons to flush"!
At the same time, of course, we also started to see a rise in continuous flows and other strange water uses within homes. WRc's work with the Identiflow system allowed us to capture at a very high resolution changes in flow patterns and, by working with households, identify the cause of some of the peculiar events. I remember vividly one particular study which had our analysts stumped. At a number of properties we were seeing regular low volume 'spurts' of water being used and we couldn't relate this to a particular water using device.
Our analysts were staring at daily water use patterns like the one below - countless events throughout day and night, running for weeks. The image shows a very high resolution flow profile for just one day at a household property.
We were lucky enough to be able to access the houses in question and identify that this strange behaviour was caused by sticking toilet valves. This isn't a constant leak... water dripping through or under a poorly seated valve. It is short and continuous 1litre mini-flushes, if you like, which resulted in between 500 and 800 litres being used over the course of each week - just from these 'sticky' events alone. On one housing development, from a sample of a handful of properties, two toilets were found to be behaving in this way.
Most recently there have been studies identifying the prevalence of leaky loos through a whole range of approaches, and facilitated significantly by the roll out of smart metering in some areas too. This continued roll out will faster future identification of problems within homes... which will hopefully encourage faster repair of the problem. But here's one final problem to add into the mix. We all love our luxury 'hotel look' bathrooms, and it has seen us shift to more hidden cisterns in our bathrooms. A cleverly designed and well installed bathroom will allow for the cistern still to be accessed for maintenance purposes. However frequently it is found that the cistern is inappropriately tiled in, making it very hard to access for any significant repair. So whilst the household might be aware of the problem, and even willing to call somebody out to help repair, the total cost of the fix might just be too great for them to justify.
So there we have it, my reflections on toilets. The bathroom industry has done a great service by driving down flush volumes and making dual-flush and low volume cisterns common place. This has been aided and abetted by the Water Regulations, and of course Part G of the Building Regulations.
What we do need, however, is to acknowledge the technical challenges that exist, along with ensuring that flush features are designed with both user experience and maintenance in mind. It's a responsibility on all of us to identify and remove wasteful water practices.
We still have some way to go to ensure that:
Most importantly of all, I would ask each and every person who reads the BBC news article not to get disillusioned with water efficiency. We need innovation, we need improvement, and with each new product or technology might come a number of pitfalls to trip us up. But we have to keep trying - it's a responsibility on all of us to identify and remove wasteful water practices. For me, the BBC article and the conversation it generates shouldn't be a finger pointing exercise to find blame; its a cry for help to overcome the problems and collectively move forward.