Roof Water Harvesting – Is it Practical?
Many of the pollutants in urban runoff are biodegradable, and will not do as much harm to the environment if allowed to break down. Catching roof water runoff in rain barrels is a way to save water and help the environment at the same time. The main problem with this practice is that water from a roof has lots of nasty stuff in it including harmful bacteria, dissolved dust, and any pollutants that are in the air around the roof; in addition to any substances in the roofing material or on the roof that are water soluble. With the exception of cedar shake roofs, or roofing material that contains asbestos or moss killer, most roofing material is suitable for supplying irrigation water for vegetable gardens if proper filtering is used. Some roofing material such as metal roofing with a non-toxic baked on enamel finish, will provide water that can be used for consumption providing proper filtering and testing procedures are used. Many people in places outside of the U.S. (and some in the U.
