This activity includes the introduction/safety preparation for the field trip, the activities on the day of the field trip, and the follow-up lab activities to complete data analysis. Adapted from MWRA Water Quality lesson plan. PDF of complete format is attached with this modified version.
Estimated Time of Activity
2 course periods (90-110 minutes) and one full or half-day field trip, depending on distance from school
Students will be able to complete basic water quality testing techniques in the field and laboratory setting.
Universal Design for Learning (Differentiation)
Prior to going into the field all students will undergo safety training as well as a pre-fieldtrip briefing. In the field students will work in small groups with specific goals assigned during the pre-fieldtrip briefing. Post trip will involve students working in groups to finish analyzing the collected samples
Activity Prerequisites (Pre-Activity)
An understanding of the water cycle and/or water quality may be a good pre-activity.
Pre-trip site selection: Choose a freshwater site, thinking about what you are near, where samples can be collected safely, and what will have the most meaning for your class. Possible options are nearby streams or reservoirs that may supply water. Municipal offices may be able to help locate access points for sample-taking; community water groups are also good resources.
Be sure to visit the site yourself before the field trip! Familiarize yourself on your school’s fieldtrip policies when choosing your site location. In addition, keep in mind:
- Avoid places where the banks are slippery or steep, and where vegetation or rocks restrict access.
- Avoid places where the water moves swiftly or where waves are too high.
- Select sites that are removed from roads and highways.
- If samples are collected from bridges make sure the correct sampling equipment is available.
Think about sampling locations as well. If a lake is chosen the temperature, dissolved oxygen and turbidity levels taken from the middle may differ from samples taken from the shore. If safety restrictions prevent sample collection from all desired spots try to collect data on your own that will supplement student’s data collection.
(40 minutes)Pre-trip activity: Explain to students that they will be going on a field trip to collect water samples and perform field tests.
Make sure that students understand that there is the potential to become wet and dirty in the field and this shouldn’t prevent them from participating in the activity. Casual clothes and old sneakers are preferable, and sweatshirts and cool-weather clothes strongly suggested even if the weather is warm.
Show students a map of the field trip location, indicating where they will arrive and where samples will be collected. Discuss the ecological significance of the sample site.
Describe the tests that will be performed on the water samples (Temperature, pH, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Nitrates, Total Dissolved Solids (TDS) and Salinity, Turbidity, Total Coliform Bacteria). This will be more of an overview, in-depth lessons will follow later in the unit; prior to writing the discussion.
- Temperature can indicate both thermal pollution and oxygenation levels.
- DO, BOD, pH, Turbidity are affected by temperature, water chemistry, sunlight and plant life.
- Nitrates levels are typically elevated as a response to chemical fertilizers. Tend to have higher levels around farms, parks, golf courses, and areas with many septic systems.
- Total coliform bacteria results are frequently found in untreated water samples. Coliform bacteria come from the intestines of warm-blooded animals and (depending on the test) the presence of the bacteria is all that is detected, not the levels.
- Total dissolved solids and salinity are dependent upon the proximity to a saline water source, as well as development and plant life in the vicinity.
Sampling groups should be assigned. Each group will be debriefed on their sample location, and what field test they are required to do. Each group will collect air and water temperature data as well as general water samples for use in the lab. Groups will also be assigned to specific field tests, like pH and DO sample preparation.
Each group will be provided with the attached student safety form, as well as the Field Sheet and Data Recording Form. Make sure to familiarize the students with the sheets, providing example data. Ensure that examples are written in the correct location. Have students sign and return the safety form.
(Full or half-day trip)Trip day: Not all tests must be completed in the field. Once these tests have been completed the remaining water samples can be returned to the classroom to complete the tests. Field tests must include: temperature (air and water temperature at the site), pH (measured at site because exposure to air will change pH of subsurface samples), DO (each group of students will need 20mL of fixed sample; should be completed within 8 hours of fixing the sample). Some tests may be done in the field and in the laboratory (students can compare results).
(40 minutes) Post-trip activity: All laboratory tests will take place; specifically DO test. All tests that have not been performed in the field will be performed in the lab with the collected samples. Try to ensure that students get the opportunity to perform each test. Maintain the group structure of the field trip, and treat the classroom activity like a continuation. Emphasize accurate data recording.
NYS/CCL Standards (Content Knowledge, IAD)
Pre-trip activity – example field sheet and data recording sheet are completed satisfactorily.
Field trip activity — students will fill out field sheet. Collect at the endof the day and use as assessment for trip, in addition to teacher observation.
Post-trip activity—students will complete data sheets and work in the lab. Data sheets will be collected by the teacher and used as assessment. Look for accuracy in reporting. Teacher will compile results for use by students in lab reports.
There are no formal assignments for these activities.
Field sampling equipment including water sample bottles, cooler, and possibly boots or waders depending on sample site and location.
(optional depending on site) Sampling equipment for a lake site or bridge site.
Field sampling kits.
Refrigerator to hold samples between collection and analysis.
The field trip and pre- and post-trip activities will be self-paced, based on available water quality tests and equipment, the site, the class size, and time. Make sure you read through and plan accordingly for your classroom and learning goals. In addition, be aware of your school's field trip policies, and make sure to obtain all necessary forms.