There are a few things you can do to reduce your water bill. First start off by ditching the baths and also taking shorter showers. Then you can look into installing a low-flow shower head. They fit onto any shower, so you can take it with you when you leave, and because they reduce the flow of water your save on your bill. Don’t worry they are designed to use less water but still offer a great shower. You can also install tap aerators on all your taps, this also reduces the water flow and as a result the quantity of water. For more information read here.