We owned a house with a workshop on the side. I fed water from the house and connected the garage we waste to the house drain. We moved out in 1995, splitting the properties. I have a gentlemans agreement with the owner of the house which has an unmetered water supply - I use their water and, due to the way the kitchen is built, they drain their washing machine and dishwasher waste into my workshop and out through my drain. I haven't paid any water/sewerage rates since 1995.