Water is essential for natural life and for human use. We use it in our homes and gardens, in business and industry, and in agriculture.
Rainwater is better for garden plants than tap water. It can easily be collected in a water butt. You could use this water to water your garden, wash your car, wash down paths and a number of other things.
If your home water usage is monitored by a water meter, saving this water will save you money.