Full Water Treatment Process
Water treatment involves a number of processes:
Coagulation
Raw water is pumped from the reservoir to the Winneke Treatment Plant inlet control structure, where it is mixed with liquid aluminium sulphate (alum). The alum acts as a coagulant, encouraging suspended solids and microorganisms in the raw water to bind together to form larger particles.
Clarification
The water then flows through an underground channel to a water distribution chamber that feeds the four clarifiers. Water is circulated in the clarifiers for about 3 hours. The clarifiers enhance the cohesion and entrapment of the suspended solids and remove colour from the water. Solid particles are separated from the raw water producing what is termed 'settled water' and sludge.
Filtration
The 'settled water' is delivered through concrete channels to 12 gravity filters, which remove most of the remaining suspended solids. Each filter is a rectangular, concrete structure with a bed of sand supported by a layer of course media that is supported on a layer of pebbles.
Disinfection and pH correction
After the water passes through the filters, it is disinfected (by chlorination) to destroy residual microorganisms. Lime is added to adjust the alkalinity/acidity (pH) level. The fully treated water flows into a large enclosed storage reservoir adjacent to the treatment plant. This reservoir is a buffer storage and water is released as required.
Fluoridation
We are required by State Government legislation under the Health (Fluoridation) Act 1973 to fluoridate the water supply. Fluoride is added in precise quantities downstream of the Winneke Treatment Plant at Research.