Lesson Plan

What Happens to the Water When We Brush and Flush?

Teacher and students gathered around an Enviroscape learning about wastewater.
Students learn how wastewater impacts our environment.

Overall Rating

Add your review
Grade Level:
Third Grade-Ninth Grade
50 minutes per section
Group Size:
Up to 36
National/State Standards:
Georgia Performance Standards: S3L2
water pollution, water treatment


Water from homes and businesses enters sewers or septic tanks through pipes. This wastewater is kept with other dirty water because it is unhealthy and must be kept away from our drinking water. This sewer water is sent to a water treatment plant where the unhealthy parts are removed. The water is then returned to the river sometimes cleaner than it was originally. This lesson raises real world concerns, guiding students to become better stewards of our environment.


Students will:

  • Learn the process of water treatment
  • Discuss the various amounts of water used in everyday activities
  • Learn strategies for conserving water
  • View and discuss river conditions
  • Test river water with basic water testing kit


During water treatment, 60% of suspended solids are removed. Since we often let the water run as we complete our daily routines, much of the water is already clean when it goes down the drain. Less than 1% of wastewater is actually waste. Machines remove human waste, gravel, sand, oils, grease, rags, and other objects that could damage equipment in the treatment plant. Those and other objects found are sent to the landfill. Water is then sent through a secondary treatment where aerobic bacteria break down soap, detergent, and human and food wastes, Those items are said to floc together, or clump, to be removed. The bacteria provide a healthy solution to removing organic components that might cause harm to humans and animals. The water then goes through a tertiary treatment to be filtered and disinfected. Without adequate wastewater treatment, waterborne diseases (cholera, dysentery, and typhoid) would be more prevalent. The water is then returned to local waterways such as the Chattahoochee.



Students will answer the following questions using complete sentences in their journals after lesson conclusion:

  • Where the water in my home goes when it leaves the sink.
  • Name one step in the water treatment process.
  • List two things that are removed from the water during treatment.
  • Name where the water goes after it leaves the treatment facility.
  • Name two things that they can do to reduce the amount of water I use.

Park Connections

A number of units in CRNRA and a few county and municipal parks have easy access to the Chattahoochee River as well as streams and ponds. Students must use caution along shorelines while collecting water samples for test for contaminates.


Continue water testing at different locations in the park or in different water features.

Additional Resources

Johns Creek Environmental Campus: http://www.fultoncountyga.gov/home-jcec

Clean Water Campaign: http://www.cleanwatercampaign.com/html/index.htm

LaMotte: http://www.lamotte.com/en/

World Water Monitoring Challenge ™: http://www.monitorwater.org/



wastewater, treatment facility, contaminants, bacteria, conservation, floc, coagulation, sedimentation, filtration, disinfection, phosphorus, nitrogen, ammonia, point source pollution, non-point source pollution

Last updated: April 14, 2015