Whenever you take a shower, brush your teeth, flush a toilet, or wash a load of laundry the resulting water flows from your drain through a complex series of pipes and pumping systems known as the wastewater collection system. The wastewater collection system consists of over 191 miles of sanitary sewer lines and 22 sanitary sewer pumping stations. This system transports the water from our approximately 9,000 customers to the wastewater treatment plant for processing and eventual discharge of a high quality effluent back into Old Hickory Lake. The wastewater treatment plant has the capacity to treat over 12 million gallons per day, and currently treats an average daily flow of 4 million gallons.
The Gallatin Wastewater Treatment Plant has an organic treatment capacity of 12.5 million gallons per day. The plant is also capable of being operated in "Storm Mode" with a resulting hydraulic capacity in excess of 30 million gallons per day, while meeting all NPDES effluent limitations. This facility consists of a headworks building (with three large rotary screens), two oxidation ditches, four large diameter clarifiers, four polishing clarifiers, an ultraviolet disinfection system, a 1,100 foot long, 42 inch diameter ductile iron outfall line, six digesters, a biosolids processing facility (three centrifuges with pumps and polymer feed system, and a lime stabilization system), and an operations building. The plant features a state of the art SCADA system which provides a complete system integration for the control and operation of the plant.
One of the key features of our recently completed construction at the wastewater treatment plant is a system that uses ultraviolet light to help disinfect wastewater. At the end of the wastewater treatment process, the treated effluent passes through a series of special light bulbs where it is exposed to ultraviolet light before being discharged into Old Hickory Lake. The intense ultraviolet light kills the bacteria.