What is the wastewater district served by the Alma Wastewater facility?
The district serves all of the City of Alma, and parts of Arcada and Pine River Townships.
How is the wastewater treated?
Alma's Wastewater Treatment Plant is an Activated Sludge Plant with Extended Aeration. Incoming wastewater is mixed with a mature population of bacteria (activated sludge) and is aerated for about 24 hours (plants without extended aeration have shorter detention times). Ferric chloride is added to enhance solids separation and phosphorus removal in two final clarifiers. Solids removed at the clarifiers are returned to the aeration basins. Clear water leaving the clarifiers is disinfected with chlorine before it passes through a polishing pond with a detention time of about 36 hours. Water is further clarified in the polishing pond and chlorine levels are reduced to below detection limits before water leaves the plant.
Where does the water go after treatment?
All of the water is discharged into the Pine River. Treated wastewater comprises slightly over one percent of the total river flow.
What condition is the water in when it re-enters the Pine River?
The clarity of the water is greater than that of the river, and the City meets all federal and state discharge limits.
How much sewage can be handled each day?
The plant is designed for 2.5 million gallons per day, but it is usually below the maximum level. The plant can handle up to 7.5 MGD for short periods of time. The average day the plant treats 2.0MGD.
How is the system maintained?
All equipment pertaining to the treatment and pumping, including eleven lift stations, is maintained by the staff of the Wastewater Division. Once a year everything is emptied out and inspected for corrosion. Anything mechanical is above water so it can be inspected at any time.
The sewer collection system is maintained by the Streets/Utilities Department.
What happens to the sludge after removal?
About 1.0 million gallons of liquid sludge is applied to farm land each year.