If you live in a rural or semi-rural area, it is likely that the water you drink is obtained from private water tanks or bores. To reduce the risk of water-borne illness, it is important that you have the skills and knowledge to maintain the water from these supplies so that they remain free from contamination.
Contaminated water can be responsible for major outbreaks of severe gastric illness such as gastroenteritis and infections caused by Cryptosporidium and Giardia organisms. These illnesses are particularly dangerous to the very young, the elderly and people with poor immune systems.
If you provide food/accommodation to the public, it is important that you make it known that you are on a private water supply and ensure that you have a good maintenance program in place.
Your private water supply can be contaminated by a number of different things like:
- Animal faeces – from birds, possums or washed into ground water supply.
- Human faeces – from failed septic systems or effluent irrigation.
- Pesticides – run-off from farms or blown onto roof.
- Arsenic and Heavy Metals – in soil from industrial/mining sites.
- Air pollution – run-off from roof in urban/industrial areas may contain chemicals.
- Lead – from old paint or flashing on roof.
- Algae – including blue-green algae which is not destroyed by boiling or disinfection.
- Nitrates – in some ground water.
If you suspect that your supply is contaminated, or would like to set up a sampling program, samples can be analysed at registered laboratories. A number of analysts can be found in the Yellow Pages. If you are unsure, contact Council’s Environmental Health Unit.
You can prevent/reduce contamination by collecting and storing your water carefully, and keeping up regular maintenance. This can be done by:
- Making sure surface run-off and leakage from sewage pipes and other drainage cannot enter your storage.
- Seal your water storage to prevent animals, birds and sunlight from getting in.
- Collect water only from clean roofs, not painted, tar coated or asbestos roofing.
- Clean the roof, gutters and tanks regularly.
- Install screens of filters between the supply and storage.
- Disinfect your water supply.
- Install a ‘first flush’ diversion system.
First flush diverter
The purpose of a first flush diverter is to catch the first flow of water from the roof when it rains and divert it away from the water storage tank. The first flush of water from the roof can contain amounts of bacteria from decomposed insects and bird and animal droppings which are diverted with the water, away from the water tank. A first flush water diverter will also assist in the removal of sediment, water borne heavy metals and chemical residues, all of which are undesirable elements to have in a water storage system.
How do I disinfect my supply?
If your system is above ground, maintained regularly and has sealed pipes, you should not need to disinfect the supply. However, if you find that the water is dirty or cloudy you should filter it first because any dirt particles can make disinfection ineffective.
If you find a dead animal in your tank or gutter, it will not necessarily cause illness if you drink the water. As a precaution, you should:
- Drain all the water in the tank.
- Clean inside the tank.
- Refill the tank with good quality water.
- Disinfect with chlorine.
- Remember to maintain good ventilation when you clean out any tank and always work with an assistant outside the tank.
- If you can’t get clean replacement water, all water used for cooking, food preparation or making ice should be boiled for at least one minute.