After passing through the primary clarifier, the Wastewater enters the trickling filter process consisting of huge rotating arms, which spreads the water over a wide bed of rocks. This provides a great area for large amounts of air (oxygen) to mix with the Wastewater, bacteria and other microorganisms.

Then the water reaches the bottom of this fourteen-foot deep filter, the collected sediment is pumped to the thickener tanks to combine with the primary sludge.