Wastewater treatment

Large objects – like wipes, rags, plastics, grit, and debris – are removed early to protect equipment and keep the downstream treatment processes running smoothly.

Wastewater flows into settling tanks where heavier solids sink to the bottom and oils and grease rise to the top. These materials are removed before wastewater moves to the next stage of treatment.

Microorganisms break down organic matter, nutrients, and pollutants. This is often done using aeration tanks, oxidation ponds or biological reactors that create the ideal environment for these microbes to thrive.

The partially-treated water moves into clarifiers where remaining solids settle out. These solids (known as sludge) are collected and sent for further treatment.

Depending on the treatment plant and consent requirements, additional treatment may be needed to further improve water quality. This can include filtration, nutrient removal, constructed wetlands or disinfection using technologies like ultraviolet (UV) light to reduce harmful bacteria and pathogens.

Once fully treated, the water is returned to rivers, streams, or land under strict consent conditions.

Every drop that goes down a drain eventually returns to the environment after treatment. It’s all part of the natural water cycle we rely on every day.

Tiny microorganisms – billions of them – are the real heroes of wastewater treatment. They “eat” organic matter and pollutants, cleaning the wastewater naturally.

Even “flushable” wipes don’t break down like toilet paper. They’re one of the main causes of blockages and fatbergs in pipes and pump stations.

Rainfall can significantly increase flows into the network, especially in older areas where stormwater can enter wastewater pipes.