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Water Treatment

  1. Water Treatment FacilityCollection of raw groundwater McBaine Alluvial Aquifer and Well Field
  2. AerationAddition of air, removal of dissolved gases, oxidation of iron
  3. Lime Softening – Addition of lime slurry to soften water (removal of primarily calcium)
    • Dry lime (calcium oxide) is delivered and stored in lime silos
    • Dry lime powder is mixed with water to create calcium hydroxide slurry in slaker
    • Slurry is held in slurry tanks and pumped through slurry pumps out to primary sedimentation basins
  4. Coagulation/Flocculation – Suspended solids in water combine together, creating sludge
  5. Sedimentation – Sludge settles to the bottom of basins and is removed via blowoffs to lagoons to solidify
  6. FiltrationWater is sent through filters to remove remaining suspended solids
  7. DisinfectionGroundwater systems have to comply with Groundwater Rule (4-log or 99.99% removal of viruses)
    • First dosage of chlorine in secondary basins
    • Second dosage of chlorine before filtration and ammonia after filtration. Chlorine and ammonia combine to create chloramine.
  8. Fluoridation – Addition of fluoride to the water  
  9. MonitoringTo stay in compliance and to catch problems quickly
    • Wet lab – Hourly testing of water quality parameters (pH, hardness, etc.) at several sample points (final, primary eff., etc.)
    • SCADA readings- Hourly recording of water flows to and from stations, pressures, and levels of reservoirs/towers
  10. Finished water transportation – Water sent to residents after treatment
    • Stored in pump station reservoirs (West Ash, South Pump, Hillsdale)
    • Pumped to water towers (Walnut, Shepard, Stephens)


Contact Utility Services


701 E Broadway, Columbia, MO 65205




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