Reflections of a Science Teacher: From Tap To Toilet: Interruptions in the Water Cycle

Students learn about the water cycle starting in early elementary grades. They learn how Earth's water is changes forms, between liquid (rain), solid (ice), and gas (vapor), and how it moves from the atmosphere to Earth’s natural systems. But one thing is usually left out: human interruptions in this process. Even this marvelous interactive map from the USGS misses one big interrupter: humans pulling water from surface waters or groundwaters, using it, and discharging it through septic systems or wastewater treatment plants.

Drinking Water, Wastewater, and Humans

The environmental science class took a field trip to a water treatment plant and a wastewater treatment plant to see for themselves what makes it ok for them to take a drink of tap water and to flush a toilet. As a result of this field trip, class labs, textbook readings, class discussions, etc. students were asked to write an entry describing human interruptions to the water cycle. Items students were asked to include were:

· Water withdrawal and how it can diminish the groundwater table or dry up a stream, river or lake
· How humans contaminate water and how humans can prevent some contamination
· What must be done to clean up water that is flushed down toilets

Amesbury Water Treatment Facility

Floccing Agent

Monitoring Equipment

Disinfectant Tank

Getting the Tou

Separation Tanks (one empty)

Sludge being skimmed off

Sludge skimming (note white bubbles at far end)

Samples of the Stages

Where our drinking water comes from

Amesbury Drinking Water Source

Settling Lagoon

Thanks for the tour!

Down at the other end of the line is the water that we have used and now needs treating before discharge to the river.

Amesbury Wastewater Treatment Facility