Sewer Treatment

Stuart Wastewater Treatment Plant

Bound by the approval of the Clean Water Act and the Safe Drinking Water Act of the early 1970’s, the Stuart Wastewater Treatment Plant went on line in 1975, allowing 300,000 gallons per day of wastewater to be treated and operated at a maximum monthly average flow of 600,000 gallons per day following an upgrade in 1987. The plant was originally constructed in cooperation with United Elastic Corporation to treat textile dye waste as well as normal sewage flows prior to discharge to the Mayo River.

The plant is currently overseen by Mr. Andrew Jr. Dalton. A long time employee of the Town, Mr. Dalton holds a Va. Class 2 license in wastewater treatment plant operation, which allows operation of plants with no limit of flow.

The plant is a microbiological treatment operation, utilizing bio-stabilization, sedimentation, disinfection, and de-chloration. Waste material generated at the plant is disposed of by trucking sludge to a landfill.

Andrew Jr. Dalton – Plant Manger

VPDES Permit No. VA0022985

Wastewater enters the plant by a 18 inch influent line from the Town that goes through a Bar Screen which removes large items such as rags, sticks, plastic bags etc. then the influent goes through the grit chamber to remove grit such as small rocks, and west activated sludge basins by the Influent Pumps.
Influent Pump Motors = 15 HP- 460 V- 3 Phase

East & West Activated Sludge Basins – 300,000 gallons each, 52’x54’x15’
The influent goes to the 3 clarifiers where the sludge settles and the clarified water is decanted to the contact tanks where chlorine will kill any remaining bacteria. The chlorine gas is added between clarifiers and contact tanks.
Clarifiers = 26 feet dia 10 feet deep 39,700 gals

The clarified water flows to the 3 contact tanks, then following the chlorination and prior to discharge, sulfur dioxide gas is added near the Parshall flume in order to remove the chlorine prior to discharge into the river. Under free-flow conditions the depth of water at a specified location upstream of the flume throat can be converted to a rate of flow. The Parshall flume at 6” deep maintains accurate flow rates to 1.9 MGD. (MGD = million gallons per day)

Contact tanks = 2,790 gal. each
Sludge Storage Building = 55’ x 30’ x 7’ about 620 tons
Septic Station size = 7,500 gal
Digester 1 = 20 feet dia. 12 foot deep 28,000 gals 2,333 gals per foot
Digester 2 = 25’ 6” X 25’ 6” 12 foot deep 58,523 gals 4,877 gals per foot
Blowers =Roots MD# A50630-M16/4D
Motors =2.1 HP -460 v- 3 Phase
Flume EFF = Palmer Bowlus accurate to 1.63 MGD flow Detention Time = 24 Hours

Plant is currently designed for 600,000 gals a day flow
influent BOD = 330 mg/l
influent TSS = 330 mg/l
effluent BOD = 24 mg/l
effluent TSS = 30 mg/l