Plant tour

Plant TourThis drawing shows how wastewater moves through the Kennebunk Sewer District Plant as it is treated. Below is a brief explanation of each step. You can click on each title for a more detailed explanation and a picture.


Preliminary treatment
Wastewater collected from the in-town and beach areas of Kennebunk arrives at the Water Street treatment plant where it is screened and measured.


Primary clarifiers
The wastewater then enters large tanks called clarifiers where the solid material settles to the bottom.


Biological treatment
After leaving the primary clarifiers, the wastewater enters special tanks with slowly spinning media covered drums called Rotating Biological Contactors (RBCs). Microorganisms grow on the media that digest the nutrients in the wastewater.


Final clarifiers
After leaving the RBCs, the wastewater enters another pair of clarifying tanks to remove any biosolids left in the water. A portion of the biosolids is returned to the head of the RBC tanks. This recycle enhances the treatment process.


After leaving the last clarifying tanks, the water is treated with chlorine,dechlorinated and then discharged into the Mousam River.


Treating the solids
The biosolids removed in the clarifying tanks are stored and eventually dried. After the dewatering step, the solid material is transported to a biosolids processor that further conditions it into a fertilizing soil amendment.