The Ashland Water Pollution Control Facility is a trickling filter - solids contact treatment process. The average daily flow is 4.4 million gallons per day (MGD). Treatment plant design is 10.0 MGD.
The raw wastewater enters the plant by gravity at the influent pump station. Prior to pumping, the wastewater flows through a bar screen to remove large debris. Wastewater is pumped to the intermediate screening building where organic material is removed. The wastewater is then aerated and the grit is removed.
Up to this point, all solids are landfilled. The water then flows to primary settling. Solids removed at this step are pumped to holding tanks to await further treatment. Water is now pumped to trickling filter towers. It then flows to aeration and the final settling tanks. Solids removed at this step are pumped to the primary settling tanks for removal. Water is now disinfected by ultraviolet light and pumped to Lang Creek. Solids removed in the settling processes are treated with lime and applied on farmland.