The major aim of wastewater treatment is to remove as much of the suspended solids as possible before the remaining water, called effluent, is discharged back to the environment. As solid material decays, it uses up oxygen, which is needed by the plants and animals living in the water.

"Primary treatment" removes about 60 percent of suspended solids from wastewater. This treatment also involves aerating (stirring up) the wastewater, to put oxygen back in. Secondary treatment removes more than 90 percent of suspended solids.

Think before you flush

It is crucial that residents only use the wastewater system to remove bodily waste. Cleaning products, grease and other pollutants can destroy the delicate balance of the treatment plant. It is the job of the wastewater team to balance the science of the plant to create an environment that treats the water appropriately.

Do your part and think before you flush.