Time: Approximately 50-75 minutes in the classroom for small and large group discussion following a field trip to the water sampling site and independent student research. Students could work in groups in class searching on-line for information in which case you would need an additional 50-75 minute period.
Materials: For the water collection and testing: water collecting glassware, pH meter, thermometers or temperature probes, probe to measure dissolved oxygen, and turbidity meter to measure turbidity.
Prerequisites: Basic lab skills in order to carefully collect and measure properties of water samples
Implementation: This RWLO can be used in a liberal arts chemistry course in a unit on water, pollution or chemistry in society; in a general chemistry course following a discussion of solutions, and in an introductory environmental chemistry course during a study of natural waters.
- Purchase test kits or assemble your own equipment for measuring pH, temperature, dissolved oxygen (DO), and turbidity. Kits can be purchased through WWMD at http://www.worldwatermonitoringday.com/orderkits/orderkits.html)
- Select a test site and register the site with WWMD.
- Have students read the safety precautions posted on the WWMD site and be sure they follow them as they collect and test the water samples at the site.
- Go to the body of water the class is monitoring and have groups of students measure pH, temperature, DO, and turbidity of different samples.
- Post the data on the WWMD website.
- Return as often as desired during the testing period and post data to the site each time. Have students look for changes in the data at the same site.
- Have students find out what range of values for the four indicators they are measuring reveal a clean water supply and decide if the water at their site appears to be clean or if the parameters indicate there may be a problem.
- Have students access the water quality reports from their community for the last 3-5 years. They should summarize the results from the reports and determine if their water supply is safe or needs remediation.
- Have students select five pollutants whose concentrations are measured in their water supply. Using web resources, direct them to investigate why the concentrations of these pollutants are monitored, identify sources of these pollutants, and develop a remediation plan in the event they exceed the maximum contaminant level (MCL).
- Have students present a plan that outlines how they can personally, and as a community, prevent water pollution.