You might know that a lot of our rainwater harvesting systems get installed, serviced and maintained, by a Company we work very closely with called The Rainwater Guy Ltd. They recently returned to a system that they'd installed back in 2012, because the homeowner needed a replacement part for the filter suction hose on their submersible pump.
When this system was originally installed in 2012, the owner of the house asked The Rainwater Guys to fit a water meter on both the rainwater pipe and the mains water top-up pipe that both connected to the underground tank, so that they would be able to monitor how much rainwater they used instead of mains water.
For info, this was only a small domestic rainwater harvesting system, providing rainwater to supply the downstairs toilet, washing machine and outside tap.
So, on the recent visit to replace this part on the submersible pump - which, it's worth noting, is the only thing this system has needed in the 9 years it's been used because it's been working perfectly all that time - they took advantage of the opportunity to check on the water meters...
As this photo shows, what they found was that this system has used rainwater for almost 80% of their water usage in the house, instead of using mains water. What a saving!

Proof that Rainwater Harvesting systems can save a lot of mains water!
We typically tell customers that they can save 50% of their mains water usage by using rainwater instead. This system therefore proves that in some cases, it's actually closer to an 80% saving by using rainwater instead.
Yet more proof that rainwater harvesting systems work and are a good idea.
If you're interested in helping to save mains water, perhaps rainwater harvesting is something for you to consider?