The Wastewater System | The Treatment Process

The City of Columbia Metro Wastewater Plant cleans up the wastewater from the City of Columbia and some neighboring municipalities. It can be a dirty job but our employees take pride in their protection of the environment and serving their community. The wastewater treatment plant is commonly called the "smiley face" plant. This is because of the smiley face painted on the spherical methane collection tank on the plant site. This tank is very visible from Interstate 77 near the Congaree River bridge.

The City is heavily investing in this facility over the next 5 years to increase dependability and capacity at the plant. Stay tuned for updates! Any questions or concerns can be directed to City of Columbia at (803) 545 3300.

We appreciate your help protecting the environment for future generations! To learn more about the City's ongoing outreach programs please see the Commercial FOG program and the Trash The Grease program pages.


The Wastewater System: The Plant and Collection System

The City's wastewater system serves approximately 60,000 customers and covers an area of roughly 120 square miles.

The wastewater system consists of two major components:

  • the Metro Wastewater Treatment Plant and
  • the wastewater collection system of piping networks and pump stations.

As part of running this system, the City maintains more than 1,000 miles of wastewater collection system piping, more than 50 pump stations, nearly 30,000 manholes, and a 60 million gallon per day (MGD) treatment plant!

The City's wastewater system serves approximately 60,000 customers and covers an area of roughly 120 square miles.

The City's wastewater system serves approximately 60,000 customers and covers an area of roughly 120 square miles.


The Wastewater Treatment Process

At the Metro Wastewater Treatment Plant, wastewater is treated to produce clean, disinfected water that is discharged to the Congaree River and biosolids.

At the Metro Wastewater Treatment Plant, wastewater is treated to produce clean, disinfected water that is discharged to the Congaree River and biosolids.

The Wastewater Treatment Process

Liquid Train

  • Wastewater: from residents and industry enters treatment facility
  • Fine Screens: remove floating debris from incoming wastewater
  • Grit Removal: grit particles sink and are removed
  • Primary Clarifiers: grease floats, heavy sludge sinks, and other wastewater passes through
  • Aeration Basin: air bubbles are added, and microorganisms eat food particles
  • Secondary Clarifiers: sludge sinks, and treated water passes through for disinfection
  • Chlorine Contact Basin for Disinfection: sodium hypochlorite (bleach) kills germs
  • Dechlorination: sodium bisulfite removes leftover bleach
  • Outfall to Congaree River: Clean, disinfected water is discharged to the river

Solids Train

  • Dissolved Air Floatation Thickeners: air bubbles are added to waste sludge from primary and secondary clarifiers, and skimmers remove thickened sludge from the surface and bottom of the tank
  • Anaerobic Digesters: sludge is processed, and methane gas is captured under a dome cover
  • Centrifuges: water is separated from digested sludge ("dewatered")
  • Biosolids Disposal: dewatered sludge is trucked to a landfill

Address

1136 Washington St.
Columbia, SC 29201
Directions

Phone

(803) 545 3300
24 hours a day
7 days a week