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Water Systems. Introduction Personal Water Usage. Where does water come from?. Where do you think water comes from? Discuss with your table partner and be prepared to share with the class in 2 minutes. Facts about water….
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Water Systems IntroductionPersonal Water Usage
Where does water come from? • Where do you think water comes from? • Discuss with your table partner and be prepared to share with the class in 2 minutes.
Facts about water…. • Water is the only substance found on earth naturally in three forms – solid, liquid and gas • About 70% of the earth is covered in water, 97% of that is salty or undrinkable • 3% of water on earth is freshwater but most of that is locked up in icebergs and glaciers • Of the total world's freshwater supply, 30.8% is groundwater, including soil moisture, swamp water and permafrost
Only 0.3% of total global fresh water is stored in lakes and rivers and available for our use • Canada has about 25% of the world's wetlands – the largest wetland area in the world • With approximately 8% of its territory covered by lakes, Canada has more lake area than any other country in the world Water is our precious resource!
How are You Doing? • How much water do you think you use in a day? • Copy the chart into your notes:
Experiment • List all the ways in which you use water in a typical day (wash hands, flush toilet, drink, brush teeth, etc.) • Classify the various tasks in which you used water. Use the categories “essential” and “optional”. • In small groups, gather a timer, 1Litre beaker or cylinder
Experiment • Turn on the tap and let it run as fast as you would for tasks such as getting a drink of water or washing your hands. • Use a stopwatch to determine how much time it takes to fill a 1L beaker at the rate you would normally use. • Without turning on the water, time how long you would run the water from the tap for each task you listed. • Calculate the total volume of water per day
How to Calculate • Example – say it takes 30 seconds to fill 1 L of water. • You take 60 seconds to wash your hands • Therefore, 60 x 1 / 30 = 2 Litres • This is an example of completing a ratio equation*
Analyze and Evaluate • Calculate the percentage of your estimated daily water use that is used for “essential” tasks and for “optional” tasks. • How to calculate? • Number of Optional Tasks/Essential Tasks x 100 • Let’s see what the numbers are like
Analyze and Evaluate - Homework • On average, Canadians use about 330L of water a day. Do you use more or less than this? • Do you think you use too much water in one day? • Suggest one or two ways in which you could reduce your water consumption. • Assume that you do not have any plumbing in your house and you have to walk 1 km to the nearest source of drinking water. How would your water use change? List several things that you would do differently.