How is the Water Treated so I can Drink It?
Clean, safe water is vital for everyday life. Water is essential for health, hygiene and the productivity of our community.
Depending on how your potable (treated) water has been sourced Potable (treated) and non potable water (untreated) the water treatment process varies.
Moree Plains Shire Council utilises a multiple barrier approach to ensure that drinking water is safe and aesthetically pleasing. The strength of this approach is that should there be a failure of one barrier, it may be compensated by effective operation of the remaining barriers. This minimises the likelihood of contaminants passing through the treatment system and subsequently causing harm to customers.
The water treatment process may vary depending on the technology of the plant and the water it needs to process, but the basic principles are largely the same. This section describes standard water treatment processes at Mungindi and Boggabilla.
Coagulation / Flocculation
During coagulation, liquid aluminium sulfate (alum) and/or polymer are added to untreated (raw) water. When mixed with the water, this causes the tiny particles of dirt in the water to stick together or coagulate. Next, groups of dirt particles stick together to form larger, heavier particles called flocs which are easier to remove by settling or filtration.
As the water and the floc particles progress through the treatment process, they move into sedimentation basins where the water moves slowly, causing the heavy floc particles to settle to the bottom. Floc which collects on the bottom of the basin is called sludge, and is piped to drying lagoons. In Direct Filtration, the sedimentation step is not included, and the floc is removed by filtration only.
Water flows through a filter designed to remove particles in the water. The filters are made of layers of sand and gravel, and in some cases, crushed anthracite. Filtration collects the suspended impurities in water and enhances the effectiveness of disinfection. The filters are routinely cleaned by backwashing.
Disinfection – Moree, Mungindi, Pallamallawa and Boggabilla
Water is disinfected before it enters the distribution system to ensure that any disease-causing bacteria, viruses, and parasites are destroyed. Chlorine is used because it is a very effective disinfectant, and residual concentrations can be maintained to guard against possible biological contamination in the water distribution system..
Water fluoridation is the treatment of community water supplies for the purpose of adjusting the concentration of the free fluoride ion to the optimum level sufficient to reduce dental cavities.