3.1 What water quality tells us about river health
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    WHAT WATER QUALITY TELLS US ABOUT RIVER HEALTH
Curriculum Alignment

ACT ELAs
2, 5, 9, 17, 18, 19, 20

NSW KLAs 
Years K-6: Science and Technology, HSIE
Years 7-10: Agriculture, Science, Technics, HSIE
Years 11-12: Agriculture, Chemistry, Earth and Environmental Science, Society and Culture, Biology

QLD KLAs 
SOSE, Science, Geography

SA ELs 
Futures, Interdependence, Thinking

VELS
Science, Thinking Processes, Geography


Objectives
>Students gain experience in testing water samples and understanding what good water quality means
>Students learn how to use water quality monitoring as a river health management tool

Duration of lesson
1 hour 

Materials required
>Phosphate test kits (for low and high range measurements)
>Dissolved oxygen test kit
>Nitrogen test strips
>pH meter
>EC meter
>Turbidity tube
>Large paper tablet
>Markers 
>Water Quality Field Datasheets (see below)
>Physical and Chemical Parameter Cards (see below)

Background
Physical and chemical water quality monitoring are key ways both scientists and the community can assess the health, not only of their rivers, but also of the land associated with a particular body of water.


Soil erosion. Plume of ‘dirty’ water flows into the Macquarie River after a heavy downpour. Photograph: Bill Phillips

Good application of sound water quality monitoring techniques should provide consistent and scientifically defensible results.  
The complexity of water quality as a subject is reflected in the many types of measurements that can be taken. Some of the simple measurements listed below can be made on-site — temperature, pH, dissolved oxygen and conductivity, in direct contact with the water source in question. 

Making these complex measurements can be expensive. Because of this, ongoing monitoring programs are generally carried out by government agencies. However, there are many local volunteer and schools-based programs and resources available for some general assessments. Tools available to the general public are the on-site test kits commonly used for home fish tanks and biological assessments.

Test kits and materials can be sourced through chemical supply venders such as Westlab or Vendart, or potentially borrowed from your local Catchment Management Authority or Waterwatch program coordinator.


Vocabulary
Turbidity
pH
Electrical conductivity (EC)
Sample
Salinity
Nitrogen
Turbidity tube


Lesson plan
1. Open the discussion by asking students how we might investigate the physical and chemical characteristics of a river or stream.

This should
lead to the suggestion of
using water quality testing
as a 'surrogate' for getting
measures of river health
or condition.

2. Explain how some of the tests or meters to be used mimic the human senses (like taste or smell) but that they’re safer to use! 

3. Advise the students that they will be doing the same types of water quality testing as professionals and volunteer groups do at their river or stream.

4. Explain briefly the importance of each parameter and pass out Physical and Chemical Parameter Cards as well as Water Quality Field Datasheets.

5. Discuss safety concerns and the need for careful and mature behaviour while handling water samples and test chemicals (especially these).


Caution: students below
Years 6 should not do
phosphate and dissolved
oxygen testing. These
tests should be presented
as a demonstration by
the teacher.


Water rich in nutrients from fertilisers, soil erosion, deterents etc create ideal conditions for algal blooms.
Water rich in nutrients from fertilisers, soil erosion, deterents etc create ideal conditions for algal blooms.

6. Break students up into groups of 4-6, giving each one parameter to test. Suggest that groups with meters all take a reading and average their results. Offer assistance with instructions and methodology through-out.

7. Have students record their results on the Field Data Sheets provided.  

8. When all students have recorded their results, invite the entire group to draw conclusions about the water quality.  

9. Based on the Physical and Chemical Parameter Cards, ask the students to hypothesise on the causes of any water quality concerns they’ve identified.

10. Get the students to explain what of their own behaviour may be having a deleterious impact on the waterway.

11. Ask students to hypothesise about what they, or other members of the community, can do to improve water quality. Look for answers such as:

>Tree planting
>Livestock exclusion from the waterway or river bank
>Controlling non-point (generalised) and point source pollution
>Controlling erosion
>Education of the community to reduce stormwater pollution.

Extension
Have students make a cartoon or a bumper sticker encouraging members of the community to take better care of water quality. They might like to use some of the river cartoon characters used throughout this education package.

In-class room adaptation
Provide the class with 3-4 one litre (but unlabelled) samples of water from various sources. Depending on your location, try to get samples from sources such as the school bubbler (or similar), from a nearby river, stream, wetland or a dam, or from a parkland or stormwater drain. For the final sample contaminate drinking water with either a 1/4 cup lemon juice or a 1/4 cup table salt.

After testing and sharing the results, ask students to form an opinion on which samples came from which sources.   
Return to the lesson plan at step 9. For each sample get the students to suggest what the contaminant or contaminants may be.
Continue with Lesson Plan steps 10 and 11.

Secondary pathway
Include in the monitoring:
>Phosphate testing and
>Dissolved Oxygen testing.

Work with students to complete the Field Data Sheets. Secondary students may be trained as Waterwatch volunteers and monitor a site as a class or take it on as an individual or group project over the course of the term.

Laboratory extension
Have students bring in one litre samples from their local waterway for testing.
Compare and contrast results, and encourage students to hypothesise about disparities in water quality from different locations.
Encourage students to investigate their hypotheses further with independent research.

Soil erosion associated with construction works can be a serious problem for waterways if not constrained like this. Photograph: Bill Phillips
Soil erosion associated with construction works can be a serious problem for waterways if not constrained like this. Photograph: Bill Phillips

In urban areas a common site is litter, oils, detergents and a cocktail of other pollutants washing into our creeks, lakes and rivers via stormwater channels. Photograph: Bill Phillips
In urban areas a common site is litter, oils, detergents and a cocktail of other pollutants washing into our creeks, lakes and rivers via stormwater channels. Photograph: Bill Phillip