Monitoring water quality
Focus
This activity provides opportunities for students to explore and evaluate some types of applications of science.
Students monitor water quality in their local area to see the effects of agricultural land use on the quality of water in their catchment area. Students will see how different types of land use can affect water quality in various ways.
Students investigate a number of the following parameters of water quality in their local catchment area, depending on resources available:
- dissolved oxygen
- temperature
- turbidity
- salinity
- pH
- flow
- phosphorus
- nitrogen
- faecal coliform numbers
- chlorophyll
- pesticides
- heavy metals
Students will have opportunities to:
- interpret the data gathered in the field
- draw conclusions from their interpretations
- provide alternatives to current ways in which land is used.
Science
Earth and Beyond
6.3 Students prepare scenarios to describe the potential long-term effects of changes in biodiversity caused by human action on ecosystems.
Materials
- Water quality monitoring equipment
- Queensland community waterway monitoring manual (PDF, 9.9M)*
- Water quality monitoring equipment can usually be borrowed by schools that do not have their own (see below)
Teaching considerations
Select sites suitable to your school’s program. Select one site nearest your school and, if possible, two others on the same watercourse. Most of the water quality tests performed in this activity are simple and easy to perform in the field using inexpensive equipment. Some of the tests outlined, however, are more difficult and/or costly (e.g. faecal coliform test, phosphate digestion and colorimetry, heavy metals). In some cases it may be necessary to get chemical laboratories to perform tests for you; this may also be expensive. This activity outlines the range of tests that can be performed and the equipment required, but the level of testing done during your field trip will depend on the resources available to you.
You may be able to find assistance from your local council or a local community organisation undertaking water quality monitoring.
Working scientifically
Time: whole day field excursion
- Collecting information
- Measuring
- Analysing
- Making links
- Using scientific report genres
After identifying their catchment area and the land use in the area, students (in groups) perform tests on the water quality in a waterway in their catchment area.
The water quality parameters and the method by which they may be tested are listed below. Test procedures are explained in the Queensland community waterway monitoring manual, or ask your local water quality monitoring coordinator (see ‘Teaching considerations’).
Parameters |
Best equipment |
dissolved oxygen level |
Winkler test |
temperature |
thermometer |
turbidity |
turbidity tube |
salinity |
electrical conductivity meter |
pH |
pH meter |
flow rate |
stopwatch |
phosphate level |
digestion kit and colorimeter |
nitrogen level |
colorimeter |
chlorophyll |
sample collection bottles |
faecal coliforms |
most probable number kits |
pesticides |
sample collection bottles or Elisa kits |
heavy metals |
sample collection bottles |
A number of sites (at least three) along the waterway should be sampled to get the best overall picture of what is happening in the catchment area. These sample sites should be marked on a map of the catchment area. Once various water quality parameters have been tested, students analyse the data to find evidence of pollution in the catchment.
The accuracy of tests can be improved through repeating tests and checking that equipment is correctly calibrated. Students compare their predictions of possible pollution problems with the data gathered in the field, and propose solutions to any evident pollution problems resulting from the way land is used in the catchment area.
Additional learning
Students could:
- prepare a written report for submission to the local council or Catchment Association , outlining the water catchment problems in the local area and including proposals for remedying the problems.
Gathering information about student learning
Sources of information could include:
- completed data sheets of water quality parameters
- a written scientific report including the predictions made, the methods used for testing, the results obtained, relevant evaluation and analysis of the data, conclusions reached and any proposals for more sustainable use of the agricultural land in the catchment area.
(The ‘Monitoring water quality’ activity is modified from Foster 1993, Waterwatch Action by School Communities, Department of Natural Resources, Brisbane)
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Last updated 31 August 2010
