Drop by drop, litre by litre

If you suspect that you have a leaking tap or cistern, find it and fix it. The source of a leak will not always be obvious. If you’re not sure whether your cistern is leaking, add a few drops of food colouring or water-based paint to the water in the cistern and check whether the colour appears in the toilet bowl.

Check your taps regularly to make sure they are not leaking, and replace worn parts in good time.