The average roof in the CRD can collect 272 litres of rain (60 gallons) on each nine square metres (about 100 square feet) for every 25mm (one inch) of rain. This equals hundreds of litres of free water you can use in your garden every year, for only a small investment of time and materials.
Collecting rainwater also helps to reduce the load on the sanitary sewer system, and can help to prevent flooding.