Water Treatment Process

How do you wash water? This diagram shows the steps in cleaning water to make it safe to drink.

Follow a drop of water from the source through the treatment process. Water may be treated differently in different communities depending on the quality of the water which enters the plant. This is just one example of water purification.

Groundwater is water located under ground and typically requires less treatment than water from lakes, rivers, and streams.

Stop at each treatment point and unscramble the words to show where the water is along the treatment path.

Look below to see the unscrambled answers and a little information about each treatment point.

  • Coagulation:  Coagulation removes dirt and other particles suspended in water. Alum and other chemicals are added to water to form tiny sticky particles called "floc" which attract the dirt particles. The combined weight of the dirt and the alum (floc) become heavy enough to sink to the bottom during sedimentation.
  • Sedimentation:  The heavy particles (floc) settle to the bottom and the clear water moves to filtration.
  • Filtration:  The water passes through filters, some made of layers of sand, gravel, and charcoal that help remove even smaller particles.
  • Disinfection:  Chlorine is added or some other disinfection method is used to kill any bacteria or microorganisims that may be in the water.
  • Storage:  Water is placed in a closed tank or reservoir in order for disinfection to take place. The water then flows through pipes to homes and businesses in the community.