Components of a Rainwater Harvesting System
- Capturing the rainwater
- Storing
- Filtering
- Emergency use
- Distribution for irrigation and/or designated use
Catchment Surface:
Most roof surfaces are acceptable. Roofs with smooth surfaces, like metal and concrete tile, are best for durability and rainwater quality. For a tar and gravel roof or cedar shingle roof impregnated with fire retardant, we typically recommend other roofing solutions for a rainwater system. Solar panels are also ideal catchment surfaces and are increasingly integrated into rainwater systems.
Gutters and Downspouts:
Gutters catch rainwater that is then diverted into downspouts where rain can be channeled into storage tanks. We recommend pre-filtration components to initially remove large particulates.
Pre-filtration Components:
Leaf Screens, First flush diverters or roof washers are pre-filtration components to ensure the storage of the highest quality water. First flush diverters and roof washers reduce accumulated small particles from entering the storage tank.
Storage:
Above Ground – There are many different size and shape tanks for above ground use. The most common types of storage tanks are: polyethylene, corrugated metal, concrete and Ferro cement and a wide variety of rain barrels.
Underground – There are also solutions to storing water below ground. Underground tanks or modular units can be linked together to serve as a void space to collect and store water. Used most often if space is limited or if there is a visibility issue.
Distribution:
There are energy efficient and easy-to-use pumps on the market perfect for rainwater applications. Commonly, when irrigation is desired — a pump can be used to transfer and pressurize the water. Gravity flow usually does not provide adequate pressure for most irrigation systems unless there is a large elevational difference.
Treatment and Purification:
Typically rainwater is filtered one more time before the point of use as a precaution to ensure proper irrigation system function.