Water Treatment

The City of Florence Water Department supplies drinking water to the City of Florence and the town of Killen. Most of the water supplied to Florence and Lauderdale County comes from two surface water treatment plants located on Wilson Lake and Cypress Creek. In addition, the Water Department operates two ground water wells in the Killen area.

At the treatment plants, the water is treated for consumption by six processes:

    • Rapid Mixing - The untreated water is pumped to a rapid mix chamber and aluminum sulfate (alum) and chlorine added.
    • Flocculation - This slow mixing process allows the alum treated solids to stick together forming a heavier layer of particle known as 'floc'. 
    • Sedimentation - The 'floc' is separated from the water in this process. This physical settling process allows the floc to settle to the bottom of the tank and the clear water on top is then removed. 
    • Filtration - The clear water left is filtered to remove any remnant particles. To remove these particles, the water passes through filters that consist of varying sizes of sand and anthracite coal.
    • Fluoridation and Disinfection - Fluoride is added to protect children's teeth from decay and chlorine is added for disinfection. 
    • PH Control - pH control is the final step in the treatment process. Here, lime is added for the purpose of increasing the pH of the water.
      By doing this, the water becomes alkaline instead of acidic which makes it non-corrosive and allows a thin protective coating of calcium to form on the pipe that serves as a barrier between the pipe and the water.

Well water goes through very little treatment because the soil naturally filters solids and bacteria from the water as it passes into the well. The wells in the Killen area require only two treatment processes. One is disinfection using chlorine and the other is pH control by adding sodium hydroxide.