Rainwater tanks should protect the water from contaminates like leaves, dust, pesticides, industrial pollution, vermin, insects and fertiliser sprays.
Tanks should be positioned in a shady spot, preferably away from trees to prevent leaves, etc., contaminating water.
All openings should be equipped with close fitting lids, or mesh screens.
The Inlet
Various inline screens and filters are available or can be made. Ensure that screens and filters are positioned so they are accessible for cleaning.
Openings should be screened so that the mesh gauze will fit on a collar about 50mm deep. This will allow effective water flow into the tank.
Avoid brass or copper screens as they may react with the galvanising of the tank. Ensure that screens are mosquito proof.
Overflow on Outlet
Treat this in the same way you do the inlet.
Inspection Hole
A close fitting lid which is readily removable is recommended.
Algal Growth
Light will stimulate the growth of algae in stored water. Try to exclude as much light as possible. Where an algal problem already exists, it is best to drain the tank and clean it.
The first rain after a dry spell may wash dust and other contaminants from the roof into the tank. It would be best to exclude this water by diverting the inlet pipe away from the tank. Follow-up rains should then be suitable for collection.
Further Information
To view a SA Department of Health fact sheet on rainwater tanks - http://www.dh.sa.gov.au/pehs/publications/rainwater-tanks.pdf
To view an Enhealth publication on rainwater tanks and water quality -http://enhealth.nphp.gov.au/council/pubs/documents/rainwater_tanks.pdf
view the Australian Drinking Water Guidelines - http://www.nhmrc.gov.au/publications/synopses/eh19syn.htm
Save Water in your home - http://www.sawater.com.au/SAWater/YourHome/SaveWaterInYourHome/
