Rainwater harvesting is a technique used for collecting, storing and using rainwater for landscape irrigation and other uses. The rainwater is collected from various hard surfaces such as rooftops and/or other manmade aboveground hard surfaces. For a dry climate such as we have here in South Australia, rainwater harvesting can make a huge beneficial impact on the environment.
Most rural households have to source all their water on their property, and rainwater often provides a better quality household supply than river, bore or dam water. Rainwater harvesting is not just for rural areas though. Although urban households may be connected to a reticulated, treated (mains) water supply, rainwater harvesting can significantly lower mains water usage.
What are the benefits of rainwater harvesting? It will reduce water bills, provide an alternative supply during water restrictions and help maintain a green, healthy garden. In fact, depending upon tank size and climate, rainwater harvesting can reduce mains water use by 100%. Rainwater harvesting also decreases stormwater runoff, thereby helping to reduce local flooding and scouring of creeks.
Rainwater can be collected from most roof types, depending on the quality of rainwater required.
For garden or lawn irrigation:
- collect from any roof material except unsealed asbestos
- ensure all gutters fall towards the outlets
- preferably fit an effective leaf screen to the gutters
- use gutter outlets that fit to the underside of the gutter.
For all other uses, also:
- prevent vegetation from overhanging the roof
- clean the roof and gutters before installing the system
- fit a good quality leaf screen to gutters or use a leaf-shedding gutter.
For drinking water, also avoid collecting rainwater:
- from sections of roof containing lead flashing or asbestos sheeting, and from roofs painted with pre-1980 paint — if they cannot be avoided, seal properly by preparing the surface and painting with a suitable potable-quality roof sealant, and do not collect rainwater from the first few rainfall events after sealing
- in areas where airborne toxins are present from nearby activities such as crop-dusting and chemical processing.
It is important to note that if your rainwater is to be used for human consumption, the system must be designed, operated and maintained to ensure the water quality is suitable.
If you are interested in learning more about rainwater harvesting, please have a look at the concrete rainwater tanks on the Ri-Industries website or give us a call.