Tertiary treatment is employed in wastewater treatment to remove stubborn contaminants that the secondary stage cannot remove. Examples of tertiary treatment include ultra violet treatment and membrane and sand filters. Monitoring between the secondary and tertiary process has two major benefits – energy saving and prevention of damage to the tertiary plant.

Energy can be saved on many plants by only using the tertiary plant when process conditions require it, it may be possible to bypass the tertiary plant for extended periods of time when the quality of the effluent from the secondary plant is good enough for direct discharge. The use of a low cost Turbidity monitor can make large energy and maintenance savings.

Membrane plants in particular are susceptible to damage if the turbidity levels going into the plant are higher than acceptable, again a simple low cost turbidity monitor can save costs of both parts and time.