Is It Safe To Collect Rain Water On A Roof

Use it to wash cars and outdoor equipment and to rinse patios.

Is it safe to collect rain water on a roof.

Drinkable rainwater can be collected from most roof types including undamaged asbestos colorbond zincalume and galvanized steel. Roof runoff has many outdoor uses. Although it is the homeowner s responsibility to ensure drinking water is clean he says information on the safe collection and storage of roof collected rainwater seems not to be reaching many. The study has shown that water from a roof can contain about 60 cfu 100ml of coliform bacteria relatively harmless to 50 000 cfu 100ml very likely to contain harmful pathogens and not safe to use and that a slow sand filter will vary somewhat in its ability to remove pathogens.

It is important to find out if the material or the paint used on your roof or in your gutters could contaminate your rainwater. Germs and other contaminants while useful for many things rainwater is not as pure as you might think so you can t assume it s safe to drink. And also that a first flush diverter will remove a considerable number of the pathogens but not enough to be safe. Unless the zinc content is particularly high it is safe to use on lawns and ornamental gardens.

Most studies agree that it is a good practice to eliminate the first few gallons of rainfall that is collected from the roof. However still this water can be used if the first flush of water is diverted from the roof tops. This is called the first wash and will be discussed in detail in the first filtering chapter. Rain can wash different types of contaminants into the water you collect for example bird poop on your roof could end up in your water barrel or tank.