Water Quality at Stow Lake
University of San FranciscoAuthor Profile
Used this activity? Share your experiences and modifications
Field sampling for water quality, including dissolved oxygen, conductivity, pH, alkalinity, phosphate and nitrate. Strengths- outside, real-world data, gives students a hands-on opportunity to look at water quality.
I used the activity in environmental chemistry, an introductory course for first-year graduate students. The graduate students in the program are mostly working professionals, in the environmental field, and many have come back for their MS because they don't have any academic background in science or the environmental field. So this activity could easily be done with undergrads- it's was designed as a hands-on introduction to water quality and environmental chemistry.
Skills and concepts that students must have mastered
Understand what water quality parameters, such as pH, are.
How the activity is situated in the course
I introduced water quality parameters in lecture the previous session and then we did this activity for the second session.
Content/concepts goals for this activity
Collect and evaluate real-world data. Calibrate a meter and gain experience with data collection. Write-up field data.
Higher order thinking skills goals for this activity
Spatial analysis for water quality data. Synthesis of course material on descriptions of water quality parameters with real-world results.
Other skills goals for this activity
Writing skills (to write up the report). Operating analytical equipment (pH meter, Dissolved oxygen meter), etc.
Description of the activity/assignment
In this field sampling exercise, students used Hach meters to measure pH, alkalinity, dissolved oxygen, conductivity, temperature, and nutrients to investigate water quality. We used a nearby lake in Golden Gate Park as the field sampling site because it was easily accessible from campus. The sampling was done with a large group (around 35 first-year graduate students). The activity would also be appropriate for upper division undergraduates. I divided the class into groups of 4 (one sampling box per group) and then demonstrated the equipment (one meter at a time) to the entire class. Immediately after I demonstrated each meter, I had the groups try it out with their meter. This process was rather time-consuming (>1 hr) but by the end, each group could work every piece of equipment. After this setup, groups dispersed to take their own samples. The goal was to give students experience collecting and evaluating data and make sure they understood some of the basic water quality parameters. After sampling, students wrote reports evaluating the health of the lake.
Determining whether students have met the goals
Students really enjoyed this activity, and as demonstrated in their final reports, they were able to describe and understand the meaning of different water quality parameters. This was also a good opportunity to discuss data collection- how to summarize data- what to do if a value appears incorrect- how to present data in a report- what types of data were useful, etc.More information about assessment tools and techniques.
Download teaching materials and tips
- Activity Description/Assignment (Acrobat (PDF) 16kB Jun1 10)
- Instructors Notes (PowerPoint 8.4MB Jun13 10)
- An example student paper (Acrobat (PDF) 310kB Jun1 10)