Iron bacteria are naturally-occurring micro-organisms that are present in many South-East Queensland waterways. These bacteria cause a rusty-coloured sediment or stain in the water which may also coat or discolour nearby vegetation.
Iron bacteria take iron from the water and turn it into energy, leaving a slimy deposit of iron oxide (rust) behind. The deposits are usually more noticeable during dry periods when water is still and stagnant.
Water affected by iron bacteria often has an oily sheen. Due to its unsightly appearance, iron bacteria is often mistaken for a sewage or petrol spill. However, there is no evidence to suggest that the bacteria are harmful to our waterways.
Iron occurs naturally in the soil and leaches out continually into waterways. When oxygen, water and iron mix together they create the right conditions for iron bacteria to bloom.
Iron bacteria need to oxidise iron (change its chemical structure) to fulfil their energy requirements. This involves changing ferrous iron to ferric iron.
This process makes iron insoluble and produces the rust coloured slime deposits visible in waterways.
Reporting iron bacteria
It is important to remember there is no evidence that these iron bacteria adversely affect our waterways.
However, if you have spotted this condition in your area and would like it double checked, Council officers are available to investigate the problem. For further information, contact Council.