Geography Stage 4. Lesson plan Murky Waters

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1 Lesson plan Murky Waters Objective To understand water turbidity, what causes water to become turbid, impacts on ecosystems and water filtration, and ways to protect waterways Lesson schedule - Introductory discussion (10-15 mins); Group work (15 20 mins) Syllabus links see page 5 Materials 3 clear plastic soft drink bottles to use as sample bottles (1 litre is a good size) if the lesson is delivered for 6-10 students at one activity station (or 9 clear bottles if used as whole class activity for students) Bucket Small amount of soil to make turbid water Printed land use photos in colour or display on screen in colour Setup 1. Start with a bucket of water and stir in a very small amount of soil. Fill (up to three) of the bottles with this slightly cloudy water. Label Sample 2 2. Add more soil to bucket and fill a second bottle (or second group of bottles) with this moderately turbid water. Label Sample 3 3. Add more soil to the bucket and stir and fill the third bottle (or third group of bottles) to make a very cloudy sample. Label Sample 1 Each activity station should be setup with land use photos (for each pair of students) and turbidity fact sheets. One set of the three labelled sample bottles can be viewed by up to 8 students The exact turbidity levels are not important as long as there is a fairly clean sample, a moderate sample, and a dirty sample. 1

2 Lesson activity whole class Introductory discussion with whole class (10-15 mins). Discussion points: Turbidity is a measure of the cloudiness or murkiness of water Lakes and rivers become turbid when fine particles such as soil sediment are washed from the catchment land surface and into the water High levels of turbidity in water for long periods can smother aquatic plants and stop them from growing due to the lack of sunlight. Aquatic creatures die when there are few plants to eat and their gills are blocked by fine particles. The water supply dams are managed to send water with a low turbidity to water filtration plants to avoid having dirty (or turbid) water causing the filters to block up. Good catchment land management practices which prevent soil erosion and stop turbid water reaching waterways reduce turbidity impacts Student thinking: making links between land use, ground cover, potential for erosion and resulting downstream water quality This stormwater collection pond at a concrete plant in Goulburn, NSW stops turbid water reaching the nearby creek. This is within the Warragamba Catchment Ask students to read the Turbidity fact sheet. Lead Q&A discussion related to fact sheet 2 Tree planting and fencing along a creek on a dairy farm protects riparian areas from damage by hardhooved cows

3 Lesson activity - group work Interpret Land use photos for Table 1 (for soil erosion potential) (15-20 mins). Students use Murky waters worksheet Teachers see Murky waters worksheet answered It may be necessary to guide students through initial completion of Table 1 Ground cover column Look at the photograph showing Urban development in a rural catchment area. In the Ground cover column of Table 1 you need to describe the ground cover for this land use. Look at the suggested descriptions at the bottom of the table Turbidity column If students decided that erosion should be moderate, they should choose the sample bottle which shows the middle level turbidity, etc Erosion is column Tell students to look at the Erosion is column on their worksheets and ask if it rained heavily at the place shown in the photo do you think a small amount, a moderate amount or a lot of soil would wash off the catchment surface and into the nearby creeks and rivers? Write - High, Medium or Low for erosion potential Students complete the task for the other two land uses - Undisturbed bushland and Abandoned Mine 3

4 Additional activity Management strategies Refer to Sediment control photos for Questions 2 & 3 Question 2. Look at the photo 4 showing the green mesh (sediment trap fence ) near works where the ground is being disturbed. How could this mesh protect creeks or rivers? Answer The mesh stops soil but lets the runoff water pass through. It works like a filter Tree planting on riverbank (riparian land) Question 3. Look at the photograph showing tree planting on a river or creek bank (riparian land). How could this planting protect the water quality? Answer As the trees grow their roots help hold soil in place. This stabilises riverbanks. Such regeneration work can be protected by fences to stop livestock animals from trampling banks, causing erosion and contaminating the water with animal faeces. Water troughs are needed for the animals drinking water as they would not have access to the fenced creeks and rivers. 4

5 Syllabus links - NSW Geography curriculum Focus Area 4G3 Global Change The changing nature of the world and responses to these changes. Contributes towards these Outcomes A student: 4.1 identifies and gathers geographical information 4.2 organises and interprets geographical information 4.4 uses a range of geographical tools Geographical tools in this focus area Photographs distinguish between oblique, aerial, ground-level photographs and satellite imagery collect and interpret photographic images Focus Area 4G1 Investigating the World An introduction to the discipline of Geography and the nature of geographical inquiry. Contributes towards these Outcomes A student: 4.1 identifies and gathers geographical information 4.2 organises and interprets geographical information 4.6 describes the geographical processes that form and transform environments Photographs draw a line drawing; collect and interpret photographic images Syllabus links - Australian Curriculum Geography Introduction The SCA Schools Education Program is focussed on the managed water supply for some 4.5 million people and strategies to reduce the impact of catchment land uses on the quality of the water. As water is an essential resource collected largely from the populated Warragamba Catchment, the schools program makes many links to the Australian Curriculum Geography. It will be further developed as the new curriculum is implemented. The catchment areas feature a wide range of land uses including industry, mining, major roads and rail links, major regional centres, agriculture and horticulture, and Special Areas, all of which can have an impact on run off water quality. The current Stage 4 program addresses a number of the skills and content within the Australian Curriculum Geography, including the following examples: Year 7 Unit 1: Water in the World all areas Unit 2: Place and liveability the influence of accessibility to services and facilities on the liveability of places the influence of environmental quality on the liveability of places Year 8 Unit 1: Land forms and Landscapes causes and effects of degradation & protecting significant landscapes Unit 2: Changing Nations the management and planning of Australia s urban future 5