Water for the future - Gold Coast City Council

Working for our future – today

Water for the future Watersaver education program Early Stage four

The Pimpama Coomera Waterfuture Master Plan delivered a sustainable integrated urban water strategy, comprising of drinking water, rainwater, stormwater, recycled water and wastewater services to a future community of up to 150,000 Gold Coast residents. This unit takes students on an exploration of this award winning project. Water for the Future is an ideal way to give students a deeper understanding of the future of water management by investigating and exploring substances contained in water at different stages of purification and how an integrated approach to household water usage is one approach to ensuring the city has sustainable water for the future.

Acknowledgements This unit was written by Randall Hall for Griffith University’s Science on the GO!

Special thanks Dale Pearse, Sid Hooker, Louise Cassels, Richard John, Carley Freeman, Sue Street, Simone Siwka, Carrie Hillier, Kylie Catterall, Kelly O’Halloran, Catherine Longworth and Stacey Ward.

A unit for Year nine students exploring the Pimpama Coomera Waterfuture Master Plan, developed by Gold Coast City Council to deliver sustainable water to the region.

Purpose Activities in this unit have been designed to create an understanding of the Pimpama Coomera Waterfuture project on the Gold Coast and to show the features of its design. Students will be able to: ■

explore the properties of water

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identify the many uses for water within the home and the wider community as well as the different types of water

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understand the processes involved in the Pimpama Coomera Waterfuture project

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appreciate the need to conserve water as a precious resource.

An initiative of Gold Coast City Council in partnership with Griffith University, Gold Coast Campus.

Water for the future Unit at a glance

Water for the future Lesson 1 Lesson 2

Solubility What other things dissolve?

Water quality testing Lesson 3 Lesson 4

Water pressure and flow What's in the water?

Urban water cycle Lesson 5

Pimpama Coomera Waterfuture

Testing detergents Lesson 6 Lesson 7

How can we use greywater? What else is in greywater?

Water futures Lesson 8

Designing a water future high-rise

Excursion Visit to a wastewater treatment plant

Information for teachers

Water for the future

Lesson plan 1 Theme: Water for the future Lesson: Solubility


Lesson at a glance This activity gives students opportunities to investigate the solubility of salts and engage with the terms solute, solvent and saturated solutions.

Links to essential learnings Ways of working Students are able to: ●

identify problems and issues, forumulate scientific questions and design investigations

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communicate scientific ideas, explanations, conclusions, decisions and data, using scientific argument and terminology, in appropriate formats

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reflect on different perspectives and evaluate the influence of people's values and culture on the applications of science.

Knowledge and understanding Students know and understand that: ●

immediate and long-term consequences of human activity can be predicted by considering past and present events

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responsible, ethical and informed decisions about social priorities often require the application of scientific understanding.

Water for the future Information for teachers

Lesson plan 1

Assessment focus Diagnostic assessment is used to find out what the students know about water use and the need to conserve water. Teachers can gauge the level of understanding and use this to modify/plan future learning experiences. Teacher background information

Solubility is a physical property referring to the ability of a given substance, the solute, to dissolve in a solvent. It is measured in terms of the most amount of solute dissolved in a solvent. When no more solute can be dissolved in a solvent the solution is said to be saturated. An example of a solute would be salt, dissolved in a solvent such as water. Water is a universal solvent. When no more salt can be dissolved in the water the solution is said to be saturated. Solubility is affected by: ●

the types of solutes and solvents used

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temperature (generally, an increase in the temperature of the solution increases the solubility of a solid solute)

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pressure can affect the solubility of gases but has little or no effect on liquid or solid solutes.

Make your water mark!

Equipment ■

beakers

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thermometers

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bunsen burners

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tripods, gauze mats

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different salts (cooking salt, rock salt, table salt, salt flakes, pool salt)


Lesson plan 1

Lesson steps 1. Discuss solubility with the students. ●

What does solubility mean?

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What types of things are soluble? What types of household substances are soluble?

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How can we tell if they are? What tests could we perform to see if things are soluble or not?

2. Discuss the terms solubility, solvents, solutes and saturated solutions. 3. Ask students to devise, in groups of three, a way of determining how much salt can be dissolved into a beaker of water. 4. Have the students perform their investigations and record their results. 5. As a class, discuss the results and any variables that may have led to differences in the results of the groups. Possible responses: i.

The nature of the salt used.

ii. The size of the salt grains. iii. The temperature of the water. iv. The amount of stirring.


6. Ask the students to identify one of these variables and devise an investigation to test the effect of this variable on the solubility of salt. 7. As part of their tests the students must also develop a way of recording and displaying their observations and results. 8. Remind the students of, and discuss, the principles of a fair test. 9. After consulting with the students about their devised investigations, have the students perform their tests. 10. As a whole class, discuss the different investigations and results. 11. As a class, discuss the implications of dissolved salts in the environment and what implications dissolved salts could have as a component of greywater. 12. What measures could be taken to limit the amount of dissolved salts in greywater? Optional

Students can research what other household substances contain dissolved salts such as table salt.


Lesson plan 2 Lesson: What other things dissolve?


Lesson at a glance Students build on previous lesson, exploring the different solubilities of common household substances found in greywater.



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Lesson plan 2

Assessment focus Diagnostic assessment in this engage phase is used to find out what the students already know about water usage and the needs to conserve water. Teachers can gauge the level of student understanding and use this to modify/plan future learning experiences. Teacher background information Solubility is a physical property referring to the ability of a given substance, the solute, to dissolve in a solvent. It is measured in terms of the most amount of solute dissolved in a solvent. When no more solute can be dissolved in a solvent the solution is said to be saturated. An example of a solute would be salt, dissolved in a solvent such as water. Water is a universal solvent. When no more salt can be dissolved in the water the solution is said to be saturated. Solubility is affected by: ●

the types of solutes and solvents used

●

temperature (generally, an increase in the temperature of the solution increases the solubility of a solid solute)

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pressure can affect the solubility of gases but has little or no affect on liquid or solid solutes.

Greywater is untreated water from kitchen sinks, bathrooms and laundry drains. It has not been cleaned or treated and is piped away from homes using wastewater systems.


Equipment ■

filter papers

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disposable pipettes

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test tubes

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beakers

Household substances that could be a component of greywater: ■

clothes washing powders

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toothpaste

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sugar

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oil

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milo

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cornflour

Lesson plan 2


Lesson steps 1. Revisit solubility with the students. ●

What does solubility mean?

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What types of things are soluble? What types of household substances are soluble?

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How can we tell if they are? What tests could we perform to see if things are soluble or not?

2. Discuss with students other substances from around the home that make up greywater. 3. Present the students with the substances that they will be investigating (clothes washing powder, toothpaste, sugar, oil, Milo, cornflour). 4. Ask the students, in groups of three, to place the substances in order from most soluble to least soluble. 5. Ask the students to devise a way of determining which of the substances can be dissolved into a beaker of water and compare their solubility. 6. As part of devising their tests the students must also develop a way of recording and displaying their observations and results. 7. Remind the students, and discuss, the principles of a fair test. ●

Students must use the same amount of all solutes.

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Students must use the same amount of solvent for each test.

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The solutions should be stirred for the same amount of time for each test.

8. Discuss with students possible uses for the filter paper in testing how soluble a substance is. ●

Ideally students will conclude that after being mixed for a set time (such as two minutes) each of the solutions should be passed through the filter paper and the trapped residues observed and observations recorded.

9. After consulting with the students about their devised investigations, have the students perform their tests. 10. Have the students use their observations to list the substances in order of most soluble to least soluble and compare them to their earlier predictions. 11. As a whole class, discuss the different investigations and results. 12. Lead the class in a discussion of the implications of dissolved substances in the environment. 13. Discuss with students the need to trap materials/substances that are insoluble in water before they enter the environment. 14. Which of the substances would be easiest to remove from the water? 15. Ask the students in groups, to develop a brochure/pamphlet for use in the home to make the community aware of what they are putting down the drains.



Lesson plan 3 Theme: Water quality testing Lesson: Water pressure and flow


Lesson at a glance This activity gives students chances to understand the principles of water pressure, such as how to measure pressure and the flow of water under pressure. In a community such as the Pimpama Coomera Waterfuture Master Plan, water must be moved to different areas. In the following activities, students learn how this is done.



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Lesson plan 3

Assessment focus Formative assessment Is ongoing throughout this unit and gives teachers the chance to monitor student understandings and give feedback to their responses, enabling them to gain a deeper understanding of concepts.

Can water flow uphill? Teacher background information Irrigation water is often held in open channels. To move water into paddocks to water a crop (such as cotton) the water has to get over the paddock bank. When a polythene pipe is used to pull off water, the water has to flow up to get over the bank. Pumping water uses fuel and costs money; this method just needs man power. Air locks can be a problem.




Lesson plan 3

Lesson steps (a) 1. Arrange two of the pots beside each other, one upside down. Place the third pot on top of the upside down pot. 2. Fill the upper pot with water. 3. Experiment with ways to get the water flowing. Hint: ●

fill the tube completely with water and then shut off both ends with your fingers

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lay one end of the tube into the water of the upper pot and the other end into the pot below

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take your fingers off the ends of the tube.

4. Observe the water in the tube and try to explain what happens, write this down. 5. Compare your explanations with those of your classmates. Are there differences? 6. Explain why water can flow over the rim of an aquarium if a tube is used.

Water pressure Where is pressure greatest? Teacher background information Certainly you have tried to dive to the bottom of a swimming pool. It's not so easy. On the bottom, you felt the pressure of water on your body and especially in your ears. Pressure can be used to move water through pipes and appliances in your home.


Equipment ■

three big cooking pots

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one transparent plastic tube


Lesson plan 3

Lesson steps (b) 1. Using the needle, heat end with a match and place four holes equidistant up the side of the two-litre bottle. 2. Place a strip of sticky tape over the holes firmly. 3. Place upright in a tidy tray. 4. Using food dye to make water easier to see, fill with water. 5. Show the bottle to the students. 6. When the tape is pulled off what will the water do as it comes out? 7. Sketch your idea. 8. Pull off the strip of tape with one movement. 9. What did the water do as it came out? Sketch your observations. 10. Was your guess correct? Explain your observations. 11. Why did the squirts of water go different lengths? 12. Where do you think the pressure (push) is greater?

Measuring the difference Teacher background information What might happen if a water tank sprung a leak? Suppose you fill a plastic soft drink bottle with water and put a hole in its side, what will happen to the water? What if the bottle is only half full?


Equipment ■

two litre plastic bottle, with lid

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heated sewing needle

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tidy tray

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water

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food dye

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sticky tape


Lesson plan 3

Lesson steps (c) 1. Put the can or plastic box upside down in one corner of the pan. 2. Make a hole near the bottom of the one-litre bottle using the thumb tack. Leave the tack in the hole. 3. Fill the one-litre bottle with 5 centimetres of water. 4. Put the bottle on the can or box with the hole pointing to the opposite corner. Pull out the thumb-tack and measure how far the water squirts into the pan from the edge of the bottle.

5. Put the thumb tack back in. Record your result. 6. Repeat steps three to five for each of the entries in the following table. 7. When you have finished, graph your results. Remember to label your graph. Results Optional

While the water is still squirting out of the bottle, put on the lid. Observe what happens. Try to explain why this happened.

Height of water in bottle observations

Distance water squirts (centimetres)

5 centimetres

10 centimetres

15 centimetres

20 centimetres

25 centimetres

Applying pressure to water in pipes Teacher background information In some towns and cities, reservoirs are on hills around the city. Gravity is used to generate pressure and force the water through pipes. This saves on pumping but causes quite large variations in the pressure of water coming out of your tap. In this activity, students can investigate the effect of height changes to water pressure and flow.


Equipment ■

can or plastic box

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one-litre bottle with lid

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pan

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ruler

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bottle cap

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soft drink bottle

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thumb tack

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water

Average


Lesson plan 3

Lesson steps (d) 1. Take a garden hose and fill it with water. (Curl the hose up in a large basin or bucket filled with water). 2. Once all the air bubbles are out place a thumb over the end so the water cannot pour out. 3. Also block the other end using a thumb. 4. If the two ends are held up together at the same height, will any water come out when the thumbs are removed? Explain the result. 5. What is the best position for the hose ends so that the longest squirt possible can be achieved? 6. If one end of the hose is held higher will this make the water come out faster? 7. Why does the volume of water pouring out reduce after a few seconds? 8. What would you have to do to maintain the pressure? 9. Design an experiment to measure what is happening. (Use the height as the variable; that is, the thing that is changed, while everything else stays the same) Optional

How could this hose filled with water be used to measure and mark a fixed height around the room?


Equipment ■

short section of garden hose (or clear plastic piping).

■

water source.

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bucket or basin to collect the water.


Lesson plan 4 Theme: Water quality testing Lesson: What’s in the water?


Lesson at a glance This activity gives students the chance to investigate different types of water and what it might contain. This activity is designed to give students opportunities to take part in experiments that test for pH, iron, nitrate and copper.



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Lesson plan 4

Assessment focus Diagnostic assessment in this engage phase is used to find out what the students already know about water testing and the substances that can be found in it. By conducting this lesson teachers are able to gauge the level of student understanding and use this to modify/plan future learning experiences.

Equipment For each group of three students: One dropper bottle of each of the following: ■

universal indicator solution

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five per cent ammonia

Teacher background information

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potassium thiocyanate

Wear safety goggles at all times during these experiments. Do not allow the solutions to touch the skin or clothing. Clean up any spills immediately. If accidental contact occurs, rinse the exposed areas. Following are suggested standards for acceptable levels of each substance.

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rain water sample

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creek water sample

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tap water sample

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bottled water sample

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distilled water sample

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one 60 millilitre dropper bottle of 0.5M (Molar) hydrochloric acid (HCI) solution

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one container of nitrate indicator powder

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one rubber test tube stopper

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one stir stick

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one dropper

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test tubes

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test tube rack

pH:

Iron:

Nitrate:

A pH level between 6.5 and 8.5 is acceptable. pH is a measure of the acidity or alkalinity of a substance. Water with a high or low pH can be harmful to the environment, especially aquatic plants and animals. Such water can also corrode pipes and release harmful metals from the pipes into the drinking water supply. Natural seawater is slightly alkaline pH 8.2 so when the water is tested in estuarine environments the pH is naturally above fresh water levels. Iron levels should not exceed 100 parts per million (ppm). Levels over 300 ppm affect the appearance and taste of water. Nitrate levels should not exceed 100ppm in drinking water. High levels may cause serious health problems in infants, including brain damage or death. Nitrates prevent the haemoglobin in the blood of infants and some sensitive adults from carrying enough oxygen through the body. Nitrates are essential plant and animal nutrients that come from the weathering of rocks and the decomposition of organic matter. They occur naturally in very low concentrations in Australian soils and waterways. When a waterway has an influx of nutrients, the chance of an algae bloom increases greatly.

Sources of nitrate compounds in waterways include: ●

sewer leaks and sewage overflows

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manure from feedlots, dairies and pet droppings

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decomposing organic material

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fertilisers and industrial wastes.

Copper: copper levels should not exceed 1.3ppm in drinking water. Short periods of exposure to levels over 1.3ppm can cause nausea and vomiting. Longer periods of exposure over many years can cause kidney or liver damage.


For each student: ■

one pair of safety goggles


Lesson plan 4

Lesson steps Testing the pH: 1. Put 10 drops of each water sample and 10 drops of distilled water into separate test tubes in the test tube rack.

2. Add one drop of universal indicator solution to the four water samples and the distilled water in the test tubes. Use the chart below to find the pH of the sample. Record the result of each sample. Rinse out all the test tubes when finished.

Colour

Approximate pH range

Red/red-orange

0-3

Orange

3-5

Pale orange/yellow

5-6.5

Yellow-green/green

6.5-8.5

Blue-green

8.5-10

Blue

10.5-14

Testing for iron:

Testing for nitrates:

3. Put 10 drops of each water sample and 10 drops of distilled water into separate test tubes in the test tube rack.

7. Add three millilitres of one of the four water samples to a test tube. 8. Add 10 drops of 0.5M hydrochloric acid solution.

4. Add one drop of 0.1M potassium thiocyanate to the four water samples and the distilled water in the test tubes. Record the colour of each solution in each test tube. 5. Add one drop of hydrochloric acid to each cup and record your observations. 6. A reddish orange colour indicates the presence of iron. (Note: the smallest concentration of iron this test can detect is 500ppm). Rinse out all the test tubes when finished.

9. With your stir stick, add two level scoops of nitrate indicator powder. 10. Use the rubber stopper to cap the test tube and shake until the powder is completely dissolved. Wait one minute. 11. A purple colour indicates the presence of nitrates. Hint: compare the colour to the original sample or control if you are not sure of the test result (light purple indicates low amounts of nitrates, medium to dark purple is cause for concern). 12. Repeat the procedure for the other water samples and the distilled water. Record your observations. Rinse out all the test tubes when finished.


Lesson plan 4

Testing for copper: 13. Put 10 drops of each water sample and 10 drops of distilled water into separate test tubes in the test tube rack. 14. Add five drops of five per cent ammonia to the four water samples and the distilled water in the test tube tray. If a light blue colour appears, copper levels are over two ppm. Record your observations. Rinse out all test tubes when finished. 15. Compare your results to the other groups’ results. Are they the same? Explain. Based on your comparison, are there any you would retest? 16. Discuss how all the water samples compare to the suggested standards. 17. What might have caused any contaminations that were found in the water? 18. How could these samples be treated to make them more suitable for use? Optional

Research the possible effects of other chemicals, such as heavy metals, in the water supply.




Lesson plan 5 Theme: Urban water cycle Lesson: Pimpama Coomera Waterfuture


Lesson at a glance This web based activity gives students the chance to explore the Gold Coast City Council website as they retrieve information about the Pimpama Coomera Waterfuture project. The web quest is designed to allow students to gain a good understanding of the project as well as an appreciation for its implications on water use on the Gold Coast.



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Lesson plan 5

Assessment focus Formative assessment is ongoing through this unit and gives teachers the chance to monitor student understandings and give feedback to their responses, enabling them to gain a deeper understanding of concepts. Teacher background information The suburbs of Pimpama and Coomera are about 40 kilometres south of Brisbane, at the northern end of the Gold Coast. This region is one of Australia’s fastest growing residential communities and is expected to grow from about 18,000 people to around 120,000 people by 2056. The Pimpama Coomera Waterfuture Master Plan was developed by Gold Coast City Council and will deliver sustainable water and wastewater services to the region. Under the master plan, all new homes are dual-reticulated to receive Class A+ recycled water for non-drinking purposes and have mandatory rainwater tanks.

The master plan proposes to use: ●

drinking water for the kitchen and to top up rainwater tanks

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rainwater for bathrooms, laundries and hot water systems

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class A+ recycled water for toilet flushing and external use

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water sensitive urban design to reduce stormwater pollution of local waterways. Expected outcomes from the master plan include:

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reduced quantity and improved quality of stormwater runoff

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reduced quantity of treated wastewater released to the environment

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reduced greenhouse gas emissions

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reduced load on wastewater systems

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reduced use of drinking water.

For more information Gold Coast City Council goldcoast.qld.gov.au/environment



Lesson plan 5

Pimpama Coomera web quest Student hand out

Go to the Gold Coast City Council homepage: goldcoast.qld.gov.au and search 'recycled water'. While exploring the page retrieve information to respond to the following questions about one of Gold Coast City Council’s Waterfuture projects, the Pimpama Coomera Waterfuture. 1. Why is the Gold Coast an ideal community to lead a new approach to water planning, management and use? 2. Why do you think the Pimpama Coomera region was selected as the site for this Waterfuture project? 3. What does dual reticulation mean? What is delivered to homes via purple pipes? 4. There are three types of water used in houses within the Pimpama Coomera project. Fill in the table naming uses for each type of water.

Type of water

Uses in the home

5. Name five things that Class A+ recycled water should not be used for. 1. ____________________________________________________________________________________________ 2. ____________________________________________________________________________________________ 3. ____________________________________________________________________________________________ 4. ____________________________________________________________________________________________ 5. ____________________________________________________________________________________________

6. Which features of water sensitive urban design look like roadside gullies and slow, reduce and clean stormwater before it reaches our waterways? How is this achieved?



Lesson plan 5

7. Complete the following table: Water used in the homes of the Pimpama Coomera project will be broken up into the following percentages. Type of water

Per cent used

A B C D

8. What percentage of high quality drinking water is used for all uses around the home in existing communities on the Gold Coast? 9. Class A+ recycled water is produced by treating water at the Pimpama Recycled Water Treatment Plant. Complete the following retrieval chart describing the steps taken at the plant to treat water.

Pimpama Coomera Recycled Water Treatment Plant Barrier

Brief description

1

2

3

4

5

6

7



Lesson plan 5

Pimpama Coomera web quest Answer sheet

Follow the link on the Gold Coast City Council homepage: goldcoastcity.com.au While exploring the page retrieve information to respond to the following questions about one of Gold Coast City Council’s Waterfuture projects, the Pimpama Coomera Waterfuture. 1. Why is the Gold Coast an ideal community to lead a new approach to water planning, management and use? The natural environment and unique water-based lifestyle attracts huge tourist numbers and rapid population growth, which fuels constant development. 2. Why do you think the Pimpama Coomera region was selected as the site for this Waterfuture project? This region is one of Australia’s fastest growing residential communities and is expected to grow from about 18,000 people to around 120,000 people by 2056. 3. What does the term dual reticulation mean? And what is delivered to homes via purple pipes? This term applies when recycled water and drinking water are delivered to a community through two separate water networks. In Pimpama Coomera, class A+ recycled water will be delivered via a network of purple water mains. 4. There are three types of water used in houses within the Pimpama Coomera project. Fill in the table naming uses for each type of water. Type of water

Uses in the home

Drinking water

Kitchen and to top up rainwater tanks

Rainwater

Cold water for washing machines, topping up swimming pools and external use

Class A+ recycled water

Toilet flushing and external use

5. Name five things that Class A+ recycled water should not be used for. 1. Drinking. 2. Cooking/ kitchen. 3. Personal washing. 4. Evaporative cooling. 5. Clothes washing.



Lesson plan 5

6. Which features of water sensitive urban design look like roadside gullies and slow, reduce and clean stormwater before it reaches our waterways? How is this achieved? Swales. They are planted with long grasses or leafy plants or filled with stones to help remove debris and litter from stormwater as it flows through them. 7. Complete the following table: Water used in the homes of the Pimpama Coomera project will be broken up into the following percentages.

Type of water

Per cent used

A

Drinking water

16%

B

Water conservation

14%

C

Recycled water

45%

D

Rainwater

25%

8. What percentage of high quality drinking water is used for all uses around the home in existing communities on the Gold Coast? 9. Class A+ recycled water is produced by treating water at the Pimpama Recycled Water Treatment Plant. Complete the following retrieval chart describing the steps taken at the plant to treat water.

Pimpama Coomera Recycled Water Treatment Plant Barrier

Brief description

1

Preliminary treatment

2

Biological treatment

3

Anthracite filtration

4

Disinfection

5

Membrane ultra filtration

6

Intense UV disinfection

7

Chlorination


Lesson plan 5


Working for our future – today

Your guide to living with Class A+ recycled water in the Pimpama-Coomera region



Lesson plan 5

Welcome, you are now part of the most innovative water project in Queensland. The award-winning Pimpama-Coomera Waterfuture (PCWF) Master Plan region is emerging as the premier residential location in the Gold Coast’s rapidly growing northern reaches. When you choose to live in the Pimpama-Coomera area, you become part of a community at the pinnacle of sustainable urban development. Gold Coast City Council, through the PCWF Master Plan, is providing one of the largest and most innovative water projects in Queensland. The PCWF Master Plan aims to create a sustainable water future for the Pimpama-Coomera community by taking a holistic approach to water cycle management. Its innovative design in sustainability has been recognised nationally and internationally.

2005 Australian Institute of Project Management Queensland President’s Award

2006 International Water Association Project Innovation Award

2007 United Nations Association of Australia Excellence in Water Management Award

The PCWF Master Plan will see the community capture, use and re-use water in innovative ways. It will also create efficiencies in all aspects of the urban water cycle by reducing drinking water use, capturing rainfall, managing stormwater and wastewater and maximising the use of Class A+ recycled water. Class A+ recycled water is supplied to dual-reticulated homes and businesses in Pimpama-Coomera through a separate water network. This network provides residents and businesses with the ability to use recycled water for flushing toilets, watering gardens and washing cars whenever they choose.

Does your kitchen cupboard have a Class A+ recycled water sticker? They are a handy reminder for the correct use of Class A+ recycled water. If not, please call us on 1300 000 928 and we will send you one in the mail at no charge. Fridge magnet also available.

Class A+ recycled water Correct use of Class A+ recycled water:

irrigation of lawns, gardens, fruit trees and vegetable crops flushing toilets washing cars, houses and other similar outdoor uses

drinking cooking or kitchen purposes personal washing such as baths, showers, bidets and hand basins evaporative coolers

filling ornamental ponds, water features and fountains

swimming pools and spas

approved commercial, construction and industry uses

recreation, such as playing under sprinklers and water toys

fire fighting (except fire sprinkler systems)

a water source for pets and livestock

washing clothes

filling rainwater tanks and other storages

Class A+ recycled water taps and pipes are purple. Work must be undertaken by a licensed plumber.

Call 1300 000 928


goldcoast.qld.gov.au


Lesson plan 5

Class A+ recycled water in Pimpama-Coomera All new homes and businesses in the Pimpama-Coomera area have two separate pipe networks supplying their water. This means they are connected to both the potable (drinking) water network and the Class A+ recycled water network. For easy identification, the entire Class A+ recycled water network is coloured purple, including water mains, meters, pipes, taps and hoses. Class A+ recycled water is available to the Pimpama-Coomera community and is high quality recycled water not intended for drinking purposes. The cost of Class A+ recycled water is significantly lower than drinking water, allowing residents and businesses to save on water bills. For the latest pricing information contact Council on 1300 000 928.

Class A+ recycled water Can be used for:

Should not be used for:

3 3 3 3 3 3 3 3

toilet flushing

2 2 2

drinking

2 2 2 2

domestic evaporative coolers

3

external household cleaning

2 2

a water source for pets or livestock

gardens and lawns filling ornamental ponds car washing fire fighting (except fire sprinkler systems) construction and building purposes dust suppression irrigation of fruit and vegetables (should be rinsed in drinking water before consumption)


cooking or other kitchen purposes personal washing such as baths, showers, bidets or hand basins clothes washing swimming pools and spas recreation, such as water toys and playing under sprinklers filling rainwater tanks and other storages


Lesson plan 5

Living with multiple water sources The PCWF Master Plan aims to secure a sustainable water future for residents living in Pimpama-Coomera by significantly reducing the use of drinking water. It is unique because it provides a sustainable solution for all elements of the urban water cycle – drinking water, recycled water, rainwater, stormwater and wastewater.

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pl Class A+ recycled water Class A+ recycled water is supplied to specially plumbed dual reticulated homes and businesses for toilet flushing and external non-drinking use. The entire Class A+ recycled water network is coloured purple including water mains, meters, pipes and taps.

Recycled water treatment plant

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Bathroom Toilet Laundry - sink Laundry - washing machine Hot water system Back-up supply in rainwater tanks Outdoor taps (including irrigation systems)

Drinking water

Rainwater from tanks

Class A+ recycled water*

3 3 2 3 2 3 3

2 2 2 2

2 2 3 2 2 2 2

Optional

3(cold water tap only) 2 2 3

* Class A+ recycled water is the highest quality recycled water in Queensland not intended for drinking purposes.


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Tertiary treated recycled water from the wastewater treatment plant goes through three additional processes at the recycled water treatment plant to produce Class A+ recycled water.


Lesson plan 5

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Rainwater Wastewater

Drinking water is used in kitchens, bathrooms, laundries and to ‘top up’ rainwater tanks.

Tertiary treated wastewater Recycled water (Class A+) Stormwater management (WSUD)

Stormwater management - Water Sensitive Urban Design

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The 7000 hectare Pimpama-Coomera area boasts a green, environmental feel as traditional concrete guttering is replaced with Water Sensitive Urban Design (WSUD). WSUD incorporates a variety of initiatives to assist in the collection and management of stormwater run-off in an efficient, cost-effective and environmentally-friendly way. These initiatives include:

H ot w ate r s y st e m

rainwater tanks wetlands and ponds swales Swales are ‘v’ shaped ditches used instead of traditional gutters or kerbs. These are being applied to many parts of the Master Plan region to help slow the flow and filter silt and other debris from stormwater. WSUD can make your neighbourhood an attractive place to live. Residents need to be aware of the proper ways to care for specific WSUD elements. For example, swales should not be driven through as this may damage them and decrease their effectiveness.

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Wastewater travels from properties in the region to the wastewater treatment plant in Pimpama. The wastewater network is designed as a ‘smart sewer’ system. Improved wastewater systems minimise the amount of stormwater entering the wastewater network, reducing the energy levels required to treat wastewater, meaning fewer greenhouse gas emissions. Wastewater is treated through a series of physical, biological, chemical and disinfection processes at all Gold Coast wastewater treatment plants.


Lesson plan 5

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How Class A+ recycled water is produced

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Class A+ recycled water treatment process

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Ultra-violet disinfection

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Class B recycled water Highly filtered recycled water Filter membrane

Membrane ultra-filtration

Rigorous treatment, monitoring, testing and quality assurance systems at the Pimpama Recycled Water Treatment Plant have been put in place to ensure Class A+ recycled water meets environmental and health guidelines. Wastewater from the community is treated at the wastewater area of the plant through a series of processes including preliminary treatment, biological nutrient removal, anthracite filtration and disinfection. At this stage the water is classified as tertiary treated recycled water.

An nth thra raci cite te Anthracite filtration

The water then undergoes further treatment at the recycled water area of the plant, which includes ultrafiltration, ultra-violet disinfection and chlorination. The water is treated and disinfected to a Class A+ recycled water standard before it is delivered to dualreticulated homes and businesses in the PimpamaCoomera region.

Rigorous treatment, monitoring, testing and quality assurance systems have been put in place to ensure Class A+ recycled water meets environmental and health guidelines. Wastewater from the community is treated at the Pimpama Recyled Water Treatment Plant through a series of processes including preliminary treatment, biological nutrient removal, anthracite filtration and disinfection.


The water then undergoes further treatment including ultra-filtration, ultra-violet disinfection and chlorination. These processes will see the water treated and disinfected to a Class A+ recycled water standard before it is delivered to dual-reticulation homes and buisnesses in the Pimpama Coomera region.


Lesson plan 5

How to check your Class A+ recycled water plumbing Do you know if your property has had a final plumbing inspection? To check, contact Council’s Plumbing and Drainage section on 07 5582 8393. If you wish to conduct your own test, the following information is for general advice only. It is best to get in touch with a licensed plumber if you are unsure about the process.

Fact sheets Visit our website to download one of these helpful fact sheets.

Rainwater tanks fact sheet - rainwater tanks are a great way to help conserve drinking water supplies and are a requirement for all new homes in the Pimpama-Coomera area.

Water Sensitive Urban Design (WSUD) fact sheet - WSUD aims to manage the quality and quantity of stormwater to better protect the local environment and waterways.

For information and fact sheets visit goldcoastcity.com.au

The essential 7-step check for dual-reticulated properties 1. Turn off drinking water supply at the property boundary and rainwater tank pump and/or valve.

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2. Turn on all internal taps. Taps should run dry. 3. Flush all toilets. Toilets should refill if connected to recycled water supply. 4. Turn on external taps. Any external potable water taps should run dry. Taps continuing to run are connected to recycled water supply and should be coloured purple and marked with appropriate signs. 5. Turn off recycled water supply and turn on drinking water supply and rainwater tank pump and/or valve. Run recycled water supply dry via external taps or toilet flushing. 6. Turn on internal appliances. Appliances that do not fill are connected to incorrect supply. 7. Turn on recycled water supply. Slowly turn on tap connected to recycled water supply that is located furthest from meter. This will purge all air from the pipeline while it is being recharged.

For more information on this process or to report an incorrect connection, contact Gold Coast City Council on 1300 000 928.


Purple tap handles for Class A+ recycled water taps are designed to be removed to avoid incorrect use. ou can ca call ll If you need a new tap handle you Council on 1300 000 928.


Lesson plan 5

Water saving in Pimpama Coomera From the bathroom to the backyard, there are some simple things you can do to reduce your water bill and save thousands of litres of water each year. Water saving tips for the home Bathroom

• Reduce your shower time to four minutes. Even an eƫcient running shower can use nine litres per minute.

• Don’t let the tap run when brushing your

teeth or shaving. This will save up to eight litres per minute.

Kitchen Tips

• Half fill the sink to rinse dishes or clean fruit and vegetables.

• A water efficient dishwaster uses less water than washing your dishes in the sink. • Wait until you have a full load before turning on the dishwasher and use a water saving setting. This will conserve 10-30 litres for every load saved. • When buying a dishwaster, choose a water eƫcient model and look for the water eƫcient labelling.

• Install Ʃow controlled aerators. You could save more than six litres per minute.


Laundry

• If you buy a new washing machine, choose

a water efficient front-loading model with a minimum ‘4 Star’ rating. This will save up to 50 litres every wash.

• Make sure each cycle is a full load, or adjust the water level to suit the size of the load. This will save up to 10 litres each wash.

Outdoors

• Use a broom to sweep paved outdoor areas instead of hosing them down.

• Always use a trigger hose, bucket or

watering can when washing your car or watering the garden.

• Wash the car on the lawn - the lawn will get a good watering at the same time.

For more information on the international award winning Pimpama Coomera Waterfuture Master Plan, please visit www.allconnex.com.au


Lesson plan 5

South East Queensland water future Our water future

Existing supply

Communities in South East Queensland are ideal to lead a new approach to water planning, management and use. Our natural environment and unique water based lifestyle attracts huge tourist numbers and rapid population growth, which in turn fuels development.

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There is an opportunity for whole new communities to be established that use and reuse water in a revolutionary way, creating a sustainable balance between the water available and the needs of the community and environment. Water future Our water future will be one of achieving the right balance between our traditional planning and innovative new ways to manage our precious resource – water. Diversity of water sources and sustainable solutions will become a way of life, not just futuristic aspirations. This diversity and sustainability will ensure water adequate supply for the needs of our growing population and our environment, while effectively managing demand for water – achieving the right balance of supply and demand as we grow as a city. A diverse range of new and existing water sources and water saving initiatives, are being implemented to meet our future water needs, which include:


local dams and waterways.

New sources ●

desalination

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rainwater tanks

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Hinze dam wall raised

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New dam constructed at Wyaralong

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recycled water

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southern Regional Water Pipeline.

Water saving initiatives ●

pressure and leakage management

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watersaver education programs.


Lesson plan 5

Master plan glossary Blackwater

Recycled water taps

Blackwater comes from toilets and is piped from homes via the wastewater system.

These external taps have reverse threading and ‘warning – recycled water DO NOT DRINK’ signs above them. Like all recycled water pipes and fittings, they are purple. The tap handles are removable to avoid accidental use by children.

Class A+ recycled water Class A+ recycled water is Queensland’s highest quality recycled water for non drinking purposes, as defined in the Queensland Water Recycling Guidelines. It is wastewater that has been highly filtered and disinfected through two different treatment plants. Treatment involves ultrafiltration, ultra-violet disinfection and chlorination, with rigorous monitoring and testing to ensure its quality. Class B recycled water Class B recycled water is treated wastewater suitable for reuse. It has been used on the Gold Coast for many years to irrigate local sporting fields, parks and cane farms. Detention ponds / water infiltration zones These sand-based ponds are used to capture stormwater in heavy rain flows and let it filter into surrounding soil over several days. They reduce stormwater runoff that causes erosion of waterways after heavy rainfall. Dual reticulation When recycled water and drinking water are delivered to a community through two separate water networks. In Pimpama Coomera, Class A+ recycled water is delivered via a separate network of purple water mains. Greywater Greywater is untreated water from kitchen sinks, bathrooms and laundry drains. It is piped away from homes using wastewater systems. Rainwater tanks On-site storage tanks used to collect and store rainfall runoff from roofs.


Recycled water treatment plant (RWTP) This plant processes water to a high quality for reuse in the community. The Pimpama recycled water treatment plant produces Class A+ recycled water. Smart sewers Smart sewers are wastewater pipes made with superior materials and construction practices to reduce the amount of stormwater and groundwater entering the wastewater system. Stormwater Stormwater is rainwater that drains from roofs and roads after storms. It flows directly to local waterways, and does not include wastewater. Swales Swales are ‘V’ shaped depressions planted with leafy vegetation that replace traditional kerbs and guttering. They slowly filter the flow of stormwater and allow it to soak into local areas before it reaches our waterways. Wastewater Wastewater is used water from the community and/or industry. Wastewater treatment plant (WWTP) The wastewater treatment plant is a facility that treats wastewater to remove organic pollutants. Water that is passed through a wastewater treatment plant is Class B recycled water. Water sensitive urban design (WSUD) This incorporates landscaping initiatives designed to reduce the impact of stormwater from urban catchments. Pimpama Coomera includes rainwater tanks, swales, infiltration zones and detention ponds.


Lesson plan 5

Equipment This lesson is a ‘web quest’ so the students will need access to a bank of computers or a computer lab. A hard copy of the web-based fact sheets has been supplied in ‘teacher background information’ if unable to access the internet. ■

Pimpama Coomera Web Quest (page 23)

Lesson steps 1. Before visiting the labs explain that students will be exploring the Pimpama Coomera Waterfuture Master Plan. Why it is necessary? What are benefits for the Gold Coast district? 2. At the computers distribute the Pimpama Coomera Waterfuture Web Quest and ask students to explore the Gold Coast City Council's website: goldcoastcity. com.au for information and respond to the questions. 3. When completed discuss the project. 4. What are the benefits of such developments? 5. How is it different to other communities? 6. What other implications could such a design have in the region? Dual reticulation high rises perhaps? 7. What community opposition could they see to such a project? Optional

Encourage students to these types of developments. Debate the use of recycled water for drinking.



Lesson plan 6 Theme: Testing detergents Lesson: How can we use greywater?


Lesson at a glance This activity provides students opportunities to investigate the effects of detergents on the growth of plants and on the environment.


identify problems and issues, forumulate scientific questions and design investigations

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communicate scientific ideas, explanations, conclusions, decisions and data, using scientific argument and terminology, in appropriate formats

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reflect on different perspectives and evaluate the influence of people's values and culture on the applications of science.



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responsible, ethical and informed decisions about social priorities often require the application of scientific understanding.


Lesson plan 6

Assessment focus Diagnostic assessment in this engage phase is used to find out what the students already know about water usage and the needs to conserve water. By conducting this lesson teachers are able to gauge the level of student understanding and use this to modify/plan future learning experiences.

Lesson steps 1. Discuss with students what greywater is and where it can be found in the home. 2. Ask the students to brainstorm the different additives that make up greywater. 3. Discuss what students believe greywater is and is not suitable for around the home.

Equipment ■

seeds of a fast growing plant - alfalfa, bean sprouts, annual herbs

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cotton wool

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beakers or plastic cups

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water

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detergent

4. Introduce the investigation: students are going to investigate the effects of different dilutions of detergent in water on the growth of plants. 5. Instruct the students that they will be testing dilutions of 1:10, 1:25, and 1:2500 on the growth of plants. 6. Introduce the materials to be used and remind the students of the need to conduct a fair test (and thus the need for a control). 7. Have the students discuss in groups a method for making the specified dilutions. 8. Have the students devise, in groups, an investigation using the listed materials that will accurately test the effects of different dilutions of detergent on the growth of plants. 9. Remind the students that they will also have to develop a way of recording and displaying the results of their investigation. 10. Once investigations have been completed and results recorded, discuss with the students the implications of their results and what this tells us about the uses of greywater. 11. What other impacts can the addition of detergents to water have on our water supply? What other implications can this have for our waterways and catchments?



Lesson plan 7 Theme: Testing detergents Lesson: What else is in greywater?


Lesson at a glance This activity provides students opportunities to investigate substances commonly found in greywater and to test them for pH, nitrates, phosphates and potassium.



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Lesson plan 7

Assessment focus

Lesson steps

Diagnostic assessment is used to find out what the students already know about water use and the needs to conserve water. Through this lesson teachers can gauge the level of understanding and use this to modify/plan future learning experiences.

1. Discuss results from the previous lesson. 2. Encourage students to recall the additives found in greywater. 3. Working in groups, select one additive to investigate.

Teacher background information The basic fertilizer mixture is the n p k base; N=nitrogen, P=phosphorus, and K=Potassium.

4. Have the students set up their investigation reserving samples of each of the solutions for further testing. 5. During investigations demonstrate the use of universal indicator paper as a test for pH.

Equipment ■

seeds of a fast growing plant - alfalfa, bean sprouts, annual herbs

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cotton wool

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beakers or plastic cups

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water

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different components that make up greywater: clothes washing detergent, fats and oils, soaps, shampoos, conditioners, toothpaste, shaving cream, bath oils

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universal indicator paper

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soil testing kits - test for nitrates, phosphates and potassium

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plant fertiliser or list of ingredients (see teacher background knowledge)


6. Demonstrate the use of the soil testing kits. 7. Test the solutions for pH, nitrates, phosphates and potassium and record results. 8. When investigations are completed set a deadline of one or two weeks - ask students to present and discuss the results. ●

Which additives appear to have had the most adverse effect on the plants?

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Did any of the additives appear to have no effect on plant growth?

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Did any of the additives appear to enhance plant growth?

9. Discuss the ingredients of plant fertiliser. 10. Look at their results asking students to draw a conclusion based on the effect the additive they tested had on the plant and suggest why.


Lesson plan 8 Theme: Water futures Lesson: designing a waterfuture high-rise


Lesson at a glance This activity provides students opportunities to apply the understandings generated in this unit to the development of a high rise building that employs the principles of the Pimpama Coomera Waterfuture project on the Gold Coast.



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Lesson plan 8

Assessment focus Summative assessment gives students opportunities to demonstrate their findings over the course of a unit of work. It allows teachers to compare student progress with knowledge demonstrated during the diagnostic assessment earlier in the unit and evaluate student progress as well as evaluate the teaching learning process.

1. Discuss what students discovered about the Pimpama Coomera Waterfuture project on the Gold Coast.


3. What factors would determine whether a plan like this could be retrofitted to existing communities?

Increasing population - with a population expected to increase from an estimated 2.65 million in 2004 to 3.7 million by 2026, South East Queensland is one of Australia's fastest growing regions. The Gold Coast leads the way, with numbers forecast to rise to 814,500 in 2026. On average, the Gold Coast hosts over 10 million visitors every year.

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A3 paper

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pencils

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rulers

2. What features make the Pimpama Coomera Waterfuture project an effective plan for conserving water and minimising waste?

4. Discuss the types of communities that people live in rural, semi-urban, low density, high density. 5. Discuss the large tourist numbers to South East Queensland each year. 6. Could a system like this be used in all types of communities? 7. Present the students with their task: In groups, design a Waterfuture high rise development to be built beachside in Surfers Paradise. The building should demonstrate features of the Pimpama Coomera project as well as other features that your group sees as beneficial in creating a water friendly building. Your proposal will be presented to the class in the form of a building application to Gold Coast City Council. Your presentation could include: ●

diagrams

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models

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building plans

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written justifications for the features of the proposal

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facts and figures justifying the need for a Waterfuture high rise

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benefits for the region and for residents of the building.

8. Discuss the features of the project allowing time for groups to brainstorm.



Excursion Visit to a wastewater treatment plant


Lesson at a glance This activity provides students opportunities to investigate the Pimpama Coomera Recycled Water Treatment Plant and the processes used to treat wastewater into usable recycled water.



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Excursion


How is wastewater recycled?

Recycled water is wastewater treated to environmental and health guidelines. Rather than releasing it into the ocean, it is put to good use. About 20 per cent of wastewater is recycled. It has been used for irrigation for decades, saving precious town water.

Wastewater is collected from homes and businesses via the wastewater network and treated at a wastewater treatment plant.

Wastewater is water from showers, washing machines, kitchen sinks and toilets. Recycled water can be treated to different qualities, depending on its intended use. What is recycled water used for? Recycled water is used for many nondrinking purposes including: ●

irrigating agricultural crops, gardens, golf courses and other open space areas

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dust suppression, road construction

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landscaping.

Why recycle? Recycling water is important because we live on the driest continent and need to reduce pressure on our precious drinking reserves. Recycled water is a resource, not a waste.

Wastewater is treated to meet standards set by the Department of Natural Resources and Mines in order to become available as recycled water. After leaving the treatment plant, recycled water can be utilised for irrigation and industrial purposes. In the case of Pimpama recycled water, it is of a standard suitable for domestic uses such as toilet flushing and outdoor use. Recycled water that is not utilised is released into the ocean. Waste material collected at the plants, such as grit that cannot be recycled, is sent to landfill whilst nutrient rich sludge removed from the treatment plants is recycled onto farmland. Treatment plants have either recently been upgraded or will be upgraded to meet future population growth. Gold Coast City Council is responsible for collecting, treating and disposing of wastewater. The system is gravity fed, following natural catchment drainage lines, although transport to treatment plants is assisted by approximately 598 wastewater pumping stations.

It is not harmful to plants, which is why so many parks and golf courses use it to irrigate.

The collection, treatment and disposal of our wastewater is part of the water cycle that maintains the balance of water in nature.

Gold Coast City Council’s objective is to manage water resources by:

Planning an excursion

1. Reducing consumption.

Contact [email protected] to book an excursion to a recycled water treatment plant.

2. Using recycled water.



Excursion

Teacher resource Visit to a wastewater treatment plant

Recycled water storage lagoons

Pre-treatment

Treated recycled water is stored in lagoons for two to three days before being discharged. Finer material settles to the bottom.

Screening - designed to remove large solids, such as rags, paper, floating objects. This protects the pumps and prevents blockages in pipes. Grit removal - removing sand and other organic material, to help the sludge set and prevent the build up of non biodegradable materials. Extended aeration tanks Primary effluent provides the food and oxygen for micro organisms that breakdown the effluent. Air is injected by pipes and mixers. Secondary sedimentation tank This process provides clear effluent and removes settled sludge. Some sludge is returned to the extended aeration tanks as micro organisms. Chlorine contact tank Secondary effluent is treated with chlorine to kill pathogenic bacteria and viruses. This disinfects.


Dissolved air flotation Sludge from the secondary sedimentation tank is injected with air to thicken the sludge, that is, reduce the water content. Excess water is returned to pre-treatment for reprocessing. Belt press Adding chemicals to the sludge from the dissolved air flotation, clumps particles that are pressed between two belts to remove excess water. Sludge drying beds Sludge is placed in sand beds to dry, forming an easily disposable material. This may undergo further treatment to form compost and the remainder is disposed of in landfill.

Excursion


Student worksheet Visit to a wastewater treatment plant Identify where each of the processes takes place at the Pimpama Recycled Water Treatment Plant. Sludge is placed in sand beds and allowed to dry forming an easily disposable material. This may undergo further treatment to form compost and the remainder is disposed of in landfill. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Secondary recycled water is treated with chlorine to kill pathogenic bacteria and viruses. This disinfects. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ The purpose of this process is to provide clear effluent and remove settled sludge. Some sludge is returned to the extended aeration tanks as a source of micro organisms. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Treated recycled water is stored in a tank for two to three days before being discharged. Finer material settles to the bottom. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Screening - designed to remove large solids, such as rags, paper, floating objects, to protect pumps and prevent pipe blockages. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Grit removal - removing sand and organic material, to help the sludge settle and prevent the build up of non biodegradable materials. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Sludge from the secondary sedimentation tank is injected with air to thicken the sludge, that is, reduce water content. Excess water is returned to pre treatment for reprocessing. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Primary recycled water provides the food and oxygen for micro organisms that breakdown the recycled water. Air is injected by pipes and mixers. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ Adding chemicals to the sludge from the dissolved air flotation, clumps the sludge particles, which are pressed between two belts to remove excess water. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________
