Using Bottled Water to Further Student Understanding and Appreciation of Groundwater and the Environment

At a visceral level, we are connected to the earth through the water we drink. I have used a bottled water activity in my introductory general education classes to awaken student curiosity and deepen their understanding of groundwater flow and chemistry. The popularity and ubiquity of bottled water make it an engaging and relevant topic. The activity progresses from tasting different bottled waters to comparing their chemistries, and concludes by identifying some possible groundwater processes that could explain the different tastes of the waters.

I introduce the activity by having the students describe the taste of several unlabeled bottled waters to convince themselves that the waters DO taste different. I then reveal the brand of bottled waters and their origin (I select mostly spring waters that represent chemically unaltered groundwater). To explore in more detail why the water samples tasted different, we examine the conductivities and major ion concentrations (if available) of the different waters to illustrate the chemical differences between them. I then use cross-section sketches of the subsurface (including the topography, water table and stream) and several schematic groundwater flow paths to show how differences in chemistry could be attributed to differences in ages of the groundwater and/or subsurface lithology. These sketches also provide a strong conceptual view of groundwater's role in the hydrologic cycle. The activity can be followed up by discussion of such topics as the affects of well pumping, the regulation and safety of tap vs. bottled water, and the economics of bottled water.

The elegance of this activity is in its simplicity, applicability to daily life, and ability to illustrate important groundwater concepts. Hopefully after this activity students have a deeper appreciation for water and can never take a sip of bottled water in an unmindful manner again.