From catchment to tap - City of Gold Coast...From catchment to tap Lesson plan 1 Theme: Water for life Lesson: Construction of water monster Lesson at a glance This activity captures

From catchment

to tapWatersaver education program

Early stage four

Working for our future – todayWorking for our future – today

PurposeActivities in this unit have been designed to create an understanding of the importance of water in our daily lives.

They are used to illustrate how water makes its way from rain into local catchments to the resource we access daily. With this unit students will be able to:

■ recognise the importance of water as a resource

■ identify the uses for water within the home, industry and local community

■ understand how water makes its way from the catchment to our taps

■ appreciate why we need to conserve water as a precious resource

Have you ever wondered where the water from our taps comes from? This unit explores what makes water so special by taking students on a journey through the water cycle. They will follow the path water takes - from falling in the local catchments to the water we use every day in our homes – and look at alternative water sources for household use.

From catchment to tap is an ideal way to give students a deeper understanding of the local catchment area and its purpose for future water sustainability.

A unit for Year eight students mapping the journey of water on the Gold Coast

AcknowledgementsThis unit was written by Randall Hall for Griffi th University’s Science on the GO!

Special thanksDale 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.

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

Information for teachers

From catchment

to tapContents

Unit at a glance

Water for life

Lesson 1 Construction of a water monster Uses of water and water wasteLesson 2 Are you a water monster? Mapping your use of water

Water cycle

Lesson 3 Where does our water come from? Exploring the water cycle

Waterways and catchments

(Excursion to dam and catchment tour)

Lesson 4 Catchments The journey beginsLesson 5 The water highway From dam to tap

Water quality

Lesson 6 Treating dirty water The Gold Coast wayLesson 7 Water, water everywhere… Desalination

Water futures – desalination

Lesson 8 A drop in the ocean Distillation method of desalination

Excursion

The catchment crawl

Make your water mark!


From catchment

to tapLesson plan 1Theme: Water for lifeLesson: Construction of water monster

Lesson at a glance

This activity captures interest and allows students to investigate the importance of water in our daily lives.

Links to essential learnings

Ways of working

Students are able to:

● identify problems and issues formulate scientifi c questions and design investigations

● communicate scientifi c ideas, explanations, conclusions, decisions and data, using scientifi c argument and terminology, in appropriate formats

● refl ect on different perspectives and evaluate the infl uence 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

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


From catchment to tapInformation for teachers


Lesson plan 1

Assessment focus

Diagnostic assessment in this phase is used to fi nd out what the students already know about water usage and the need to conserve water on the Gold Coast. By conducting this lesson teachers are able to gauge the level of student understanding and use this to modify/plan future learning experiences.

Teacher background information

A ‘normal’ tap uses on average seven litres per minute!

Tips for saving water in the kitchen

Washing up

● Buy a water effi cient dishwasher– they can cut water use by half.

● Fill your dishwasher before running it. This saves water and energy, and reduces the amount of detergent entering the wastewater system.

● Use the economy setting on your dishwasher – save up to four litres per load.

● When rinsing dishes or washing fruit and vegetables use the plug and half fi ll the basin instead of letting the water run –save seven litres a minute.

● When washing dishes by hand, fi ll one sink with soapy water and another sink or basin with rinsing water instead of rinsing under running water - save seven litres a minute.

● If you need to run the water to get it hot, collect the cold water for reuse in the garden or for rinsing.

● Soak your pots and pans to remove foods, rather than scraping them under running water - save seven litres a minute.

● Minimise the use of a garbage disposal unit – they use up to 30 litres of water a day and send extra rubbish to wastewater treatment plants. Instead, compost your fruit and vegetable scraps and use to enrich your garden.

Cooking and drinks

● Keep a jug of water in the refrigerator instead of running the tap for cold water.

● Don’t thaw food using running water.

● Don’t use oversized saucepans – they waste water.

● Save the nutrient-rich water from cooking vegetables to water your garden.

● Place unused ice cubes in your pot plants or garden.

Tips for saving water in the bathroom

● Install a low fl ow showerhead - save more than 1800 litres a week.

● Use a shower timer – cutting your shower time to four minutes.

● Use a bucket to catch water while the shower warms up and while you are showering, and reuse in the garden.

● Turn off the tap while cleaning your teeth, shaving or washing hands –save seven litres a minute.

● Turn off the water while washing and conditioning your hair – save up to 180 litres a week.

● Instead of shaving your legs in the shower, fi ll a container of water and use it to lather up and shave before you shower and rinse your legs.

● Choose a shower over a bath - a four-minute shower uses only 48 litres compared to a full bath which uses 150 litres.

● If you bath, or if you bath small children put the plug in before you turn on the tap and fi ll to less than a third. Reuse the bath water by bucketing on the garden.

● Install a dual-fl ush toilet and save six litres per fl ush.

● Unnecessary fl ushing is a big water waster –never fl ush tissues and other rubbish down the toilet.



Lesson plan 1

Tips for saving water in the laundry

● Buy a water effi cient washing machine. Top loaders use 170-265 litres a load, while a front loader uses 100 litres or less.

● Only wash when you have a full load to save10 litres a load.

● Choose an effi cient and/or low water setting.

● Use the suds-saver setting if your machine hasone when you have more than one load to save water and detergent.

● Divert fi nal rinse water from your washing machine to your garden, but don’t use on vegetable gardens.

● If you are hand-washing clothes, use only as much water as you need in the sink, buckets or tub. Reuse this greywater in the garden.

Tips for saving water in the garden

● Install a rainwater tank and use the water for your garden, to top up the pool and other outdoor uses.

● Mulch your garden regularly to maintain moisture in the soil and control weeds that compete with plants for water.

● Regularly check outdoor taps, pipes and plumbing fi xtures for leaks.

● Select drought-tolerant plants to reduce the water your garden needs.

● Use water crystals in your garden.

● Before planting new plants, prepare the garden bed with good soil, water storing granules, wetting agents and thick layers of mulch to maximise water effi ciency.

● Group plants in the gardens that require similar amounts of water.

● Avoid watering when it is windy or during the middle of the day because it causes water to evaporate and blows it to areas where it wasn’t intended.

● Choose slow growing, water saving lawn varieties like Palmetto. They have deep roots for tolerance and don’t need mowing as often as other varieties.

● Don’t cut the lawn too short, and remember it will regenerate after a small amount of rain.

Tips for saving water in the pool

● A cover is the number one water and energy-conservation device for your pool or spa. A cover can reduce water losses to evaporation by as much as 90 per cent. This could help save up to 25,000 litres per year.

● Inspect your pool and spa frequently-under pressure, a tiny leak in a plumbing system can cause losses of more than 3000 litres in one day.

● Use your rainwater tank to top up the pool.

Tips for saving water at home and when cleaning

● Use water from a rainwater tank.

● Use a mobile commercial operator or take your car to a car wash – these operators must comply with best practice guidelines in water use.

● Use captured ‘warm-up water’ from indoors to wash your vehicle.

● Use a broom, brush or rake to sweep and clean outdoor paths and paving areas.

● Use captured ‘warm up water’ or tank water to clean windows. Vinegar and water or window cleaning products can be used to clean windows.

● General cleaning of wheelie bins and barbeques can be done with bucket fi lled from a tap or high pressure cleaning unit to prevent or address a health or safety risk.



Lesson plan 1

Lesson steps

Constructing a water monster

1. Brainstorm with students different uses for water around the home.

2. Have groups of students draw pictures of water use around their home on post-it notes to create an affi nity diagram.

Literacy focus

An affi nity diagram is a technique to elicit and organise a large amount of information on an issue from any sized group in a short time.

3. When completed, have one student from each group come to the front of the class and place the notes into similar groups, such as cleaning, cooking or garden.

4. Discuss results, where and how water is used most in the home.

5. Discuss measures students are employing to conserve water around the home.

6. Students can refl ect in their science journals about water uses in the home and ways they are attempting to save water. How have their behaviours changed?

7. Have students work in pairs to design a water monster and describe a day in the life of the ultimate water wasting creature. They should list how this water monster wastes water in his/her daily life.

8. Pose focus question: How serious is a dripping tap?

9. Ask students in groups to devise a strategy to measure the volume of a single drop of water from a leaking tap – collect 100 drops and divide the volume by 100 or count how many drops in 10 million litres

10. Ask the students to develop a procedure to calculate how much water will drip from a leaking tap in:

● one minute?

● one hour?

● one day?

● one week?

● one year?

11. What are the consequences for the environment in reference to this investigation?

Optional: Ask students to audit the school for dripping taps and calculate how much water is being wasted. Students should design ways to collect water from dripping taps to use in the school gardens.

Optional: In South East Queensland it is recommended people have four-minute showers. How could we investigate the amount of water used in a four minute shower?

Curriculum links

Art Students create a sculpture, painting or drawing of a water monster.

Maths Students calculate the water wasted by their water monster.

Drama Students act out their water monster wasting water and being caught by students conserving water.

■ science journal/book

For each pair of students:

■ beakers/measuring cylinders

■ stop watches

■ calculators

■ post-it notes

Equipment


From catchment

to tap


From catchment

to tap

Lesson plan 2Theme: Water for lifeLesson: Are you a water monster? Mapping your use of water

Lesson at a glance

This activity allows students to investigate the demands people place on local water supplies. It is designed to encourage them to explore how they use water directly and indirectly in their daily lives.


Ways of working


● identify problems and issues formulate scientifi c questions and design investigations










Lesson plan 2

Assessment focus

Diagnostic assessment in this phase is used to fi nd out what the students already know about water use and the need to conserve water. Through this lesson teachers can gauge the level of student understanding and use this to modify and plan future learning experiences.


A concept map is a diagram showing the relationships between concepts. Concepts are connected with labelled arrows, or in a downward-branching hierarchical structure used to stimulate ideas.

Working out your daily water use

1. Record the numbers from your water meter.

2. At the same time one week later, record your water meter reading.

3. Subtract the fi rst reading from the second reading.

4. Divide this number by seven to calculate your daily household use.

5. Divide this number by the number of people in your household.

How to read your meter

● Lift the lid and clean the plastic covering to expose the black and red numbers.

● There are many different meters but, with each model, the black numbers register kilolitres (kL) and the red numbers register litres.

● Record the numbers from left to right.

Important safety note: Reading water meters

Please exercise caution when removing water meter covers. They are homes for spiders and sometimes snakes. Ensure gloves are used by anyone involved in meter reading. Adult supervison is advised.



Lesson plan 2

Domestic water uses

Toilet

Single fl ush toilet 13 litresDual-half fl ush 5 litresDual-full fl ush 6 to 9 litres

Bathroom

Ordinary shower rose (8 mins) 120 litresAAA rated shower rose (8 mins) 56 litresBath-half full 80 litresBath full 140 litresBrushing teeth or shaving with tap running 5 litresBrushing teeth or shaving with tap off 1 litre

Kitchen

Washing dishes by hand (one meal) 18 litresOld dishwasher per cycle 60 litresModern dishwasher per cycle 18 litresGarbage disposal per use 10 litres

Laundry

Medium sized front loading machine per cycle 80 LitresMedium sized top loading automatic per cycle 200 Litres

Outside

Washing car with bucket (four buckets) 32 LitresWashing car with hose 400 Litres

Major uses of water on the Gold Coast (Gold Coast Water 2006/07)

Uses Volume (ML) Percentage

Bulk water sales 9 0.01%

Residential water supplied 57,883 71.4%

Commercial/industrial water supplied 15,578 19.2%

Other water supplied 7,619 9.4%

Total = 59,297 100%



Lesson plan 2

Lesson steps

Are you a water monster?

1. Revisit discussion about uses of water around the home.

2. Refer to affi nity diagram from lesson one.

3. Pose the focus question: How much water do you use in a single day?

4. Students to refl ect on their daily water use and predict how many litres they think they use in a typical day.

5. Discuss water meters and how to read them.

6. Construct a table to record predicted water use.

My daily water usage

Daily water uses Where? How much? Litres per day

TOTAL Litres per day

If everyone in our city was like me we would use______________ litres of water per day.

■ science journal/book

■ affi nity diagram

■ A3 butcher’s paper

Equipment



Lesson plan 2

7. Refer to teacher background information for fi gures.

8. Students to calculate how much water is needed if everyone on the Gold Coast was like them. (Research the current population).

9. Who else uses water?

10. Discuss water uses in the community. What industries use a lot of water? Where else is water used on the Gold Coast?

11. Introduce a concept map (refer to teacher background information).

12. In groups students construct a concept map of water uses in the home and in the community.

13. Students present concept maps to the class.

Lesson steps continued



Lesson plan 2

Am I a water monster?

My daily water usage

Daily water uses Where? How much? Litres per day

TOTAL Litres per day

If everyone in my city was like me we would use______________ litres of water per day.



Lesson plan 2

Optional Students audit their typical daily water use by recording water drunk, time in shower and so on. Compare these results with predicted results. Audit the daily water use of their family.

Optional Use group concept maps to construct a class concept map of water uses in your district.

Optional Students choose a product and research its manufacture and delivery, tracing water uses during the process.

Curriculum links

Maths Graphing of results of daily water usage. Students are asked to read meters and then calculate daily water usage.


From catchment

to tapFrom

catchmentto tap


Lesson plan 3Theme: Water cycleLesson: Where does our water come from?

Exploring the water cycle

Lesson at a glance

This activity allows students to investigate the water cycle and how it is recycled around our planet. Students investigate the condensing of water vapour in the air.


Ways of working


● identify problems and issues, formulate scientifi c questions and design investigations










Lesson plan 3

Assessment focus

Formative assessment is ongoing and allows teachers to monitor comprehension, give feedback and improve understanding of concepts.


RURAL

URBAN

FRESH WATER

STORMWATER

WASTEWATERSOLAR ENERGY

CLOUDS

RAIN

EVAPORATION

TRANSPIRATION

CREEKS

DAMRIVERS

RIVERS

CROPSIRRIGATION

CATCHMENTRUN-OFF

ESTUARIES

OUTLET

OUTLET

PIPES

WASTEWATER TREATMENT

RAWWASTEWATEROUT

PIPES

DRAIN

PIPES

PUMPINGSTATION

WATERTREATMENT

STORMWATERRUN-OFF

SEDIMENT

EXCESSRECYCLED WATER

FLOWS INTO OCEAN OR RIVERSSTORMWATER CARRYING SEDIMENT AND RUBBISH FLOWS INTO RIVERS AND SEA

CATCHMENT

CREEKS

GROUNDWATERINFILTRATION

Our Urban Water Cycle

Working for our future — today



Lesson plan 3

The water cycle

The water cycle is a continuous movement of water between the earth and the atmosphere, powered by solar energy and gravity. Water from vegetation, soils and the oceans rises into the atmosphere as water vapour and condenses. Gravity creates rain that infi ltrates to groundwater or fl ows via waterways to the sea. People use water in many ways, including storage to dams, irrigation, in the home, industrial use, and for drinking.

Where does the water in my house come from and where does it go?

You can’t see how water is delivered into your home. We turn on the tap and never think about pipes running into and out of our houses, offi ces or schools. Water fl ows through the catchments into creeks and rivers and is contained in lakes by holding dams that control the release of water downstream. It is piped from the dam to a treatment plant to remove impurities and improve quality before it travels through a pipes or ‘potable water distribution system’ into your house.

What is wastewater?

Wastewater is the water from the toilet, bath, shower, sink, dishwasher and laundry that goes down the drain. It is piped to a wastewater treatment plant where most impurities are removed and water quality is improved before it is discharged into creeks, rivers, oceans or land as recycled water.

Australia is the driest continent with uncertain rainfall levels. It is absolutely essential that everyone uses water wisely. Always turn off the tap when cleaning your teeth, keep your showers to four minutes and wash your car with a bucket – it will make a difference to conserving water.

What is stormwater?

Stormwater is rainfall that runs off roofs, roads and other surfaces and fl ows into gutters, streams and waterways. There are thousands of kilometres of stormwater drains all over South East Queensland. This is a separate system to wastewater and the water is not treated to remove impurities.

Many local councils stencil words on the stormwater drains to remind people it is untreated and everything that goes into the stormwater drain ends up in the local waterway.

Wastewater is treated. Stormwater is not. Put your rubbish into the correct bins. Rubbish left in the street or thrown into stormwater drains will end up in our creeks, rivers and the ocean.

Whole class

■ copy of 'our urban water cycle' resource sheet

■ science journal or book

■ balance or scales

Each group

✪ Lesson part one - evaporation

■ beaker

■ water

■ cling wrap

✪ Lesson part two - condensation

■ four beakers or similar containers

■ water

■ ice

■ paper towel

■ thermometers

Equipment


From catchment

to tapLesson plan 4Theme: Waterways and catchmentsLesson: Catchments - the journey begins

Lesson at a glance

This activity provides students opportunities to understand local catchments and the potential contaminants that can affect the quality of water that reaches the water treatment plants.


Ways of working




● refl ect on different perspectives and evaluate the infl uence of people's values and culture on the applications of science








Lesson plan 4

Assessment focus

Formative assessment is ongoing and allows teachers to monitor student understandings and give feedback to promote deeper understanding of concepts.


What is a potable water catchment?

A potable water catchment is an area of land bounded by natural features such as hills or mountains from which all run-off fl ows to a low point, such as a stream, river or the sea – similar to water in a bathtub fl owing to the plug hole or water that falls on a roof fl owing to a downpipe.

Under the infl uence of gravity, rain fl ows from the top of the catchment through a network of waterways, from small gullies and streams into larger rivers, to the bay or ocean.

A typical coastal catchment

Catchments and the water cycle

Catchments are an important part of the water cycle. Most water that falls onto pristine catchments is absorbed by the soil and vegetation. When it rains, it takes the water a long time to reach creeks, rivers or tributaries and it is generally clean when it fl ows into the waterways.

Catchments that don't have as much vegetation have an impervious surface that decreases the water absorbed, and increases the surface water that runs off into waterways. This surface water, or stormwater run-off, fl ows faster in disturbed catchments and can cause erosion and fl ooding. This water is usually not as clean as in pristine catchments.

Catchments and activities

Activities undertaken in catchments will ultimately affect the water quality in the waterway and its tributaries. Changes in the upper catchment may adversely affect the waterway and its associated beaches downstream.

Our activities generate pollutants we are sometimes unaware of. Construction, land clearing, washing cars, dumping garden waste or not picking up dog droppings, can adversely affect our waterways.

As stormwater travels over land, it picks up pollutants such as litter, oils, paints, soil, fertilisers, animal and garden waste. These pollutants can disturb the ecological health of our waterways and degrade their quality.



Lesson plan 4

Tallebudgera catchment facts

● Total area: 110km2

● Stream network length: 219km

● Dominant land uses: native bush, suburban, grazing, intensive agriculture.

● Headwater rise in the relatively pristine areas of the McPherson Ranges near the QLD-NSW border.

● Mid reaches fl ow through rural residential areas.

● Lower reaches not as urbanised as the catchments of Coomera and Nerang rivers.

● Mouth of Tallebudgera Creek stabilised by a rock wall.

● Riparian vegetation throughout much of the catchment.

Currumbin catchment facts



● Dominant land uses: native bush, urban grazing, intensive agriculture.

● Headwaters rise in the relatively pristine areas of the McPherson Ranges near the QLD-NSW border.

● Mid reaches fl ow through rural residential areas.

● Lower reaches not as urbanised as the catchments of Coomera and Nerang rivers.

● Mouth of Currumbin Creek almost completely blocked by a sandbar.

● Riparian vegetation intact throughout much of the catchment.

Nerang River catchment facts



● Dominant land uses: native bush, grazing, intensive agriculture, rural residential, urban headwaters rise in Lamington and Springbrook National Parks.

● The Hinze Dam impounds the Nerang River 36km upstream from its mouth.

● Mid reaches fl ow through rural areas.

● Lower reaches extensively transformed into canal developments, with restricted fl ushing within the canals.

Pimpama catchment facts



● Dominant land uses: native bush, urban, grazing, intensive agriculture.

● Dominated by intensive agriculture along the middle reaches.

● Urban development, including canal estates, expanding throughout the lower catchment.

Coomera catchment facts



● Dominant land uses: native bush, rural residential, grazing, urban.

● Headwater rise in Lamington National Park and remain largely intact.

● Mid reaches fl ow through rural areas.

● Urban development, including canal estates, expanding throughout the lower catchment, with the possibility of disturbance to acid sulphate soils.

Albert River catchment facts


● Stream network length: 1,691km

● Dominant land uses: native bush, grazing, intensive agriculture, rural residential.

● Headwaters rise in Lamington National Park and fl ows through grazing, farming and rural residential areas before joining the Logan River 11.2km upstream from its mouth.



Lesson plan 4

Nerang catchment map



Lesson plan 4

Pimpama/Coomera catchment map



Lesson plan 4

Tallebudgera catchment map



Lesson plan 4

Albert catchment map



Lesson plan 4

Lesson steps

Whole class

■ enough soil, sand and gravel to construct a mound in the school grounds (four to fi ve buckets)

■ watering can

■ water

For each group

■ copies of the local catchment facts and map.

Equipment

Catchments – The journey begins

1. Using a watering can, demonstrate rainfall and its effects on the mound of dirt that is simulating a catchment area.

2. Discuss the behaviour of the water as it fl ows. Is all the water fl owing down the side of the mound? If not, where is it going? What does this tell us about rainfall and our ability to catch it for human use?

3. Discuss groundwater and that of the water on earth. Only three per cent is fresh and only 0.3% is surface water.

4. Discuss the effects rain has on the catchment as you simulate light showers and heavy storms. What are the implications of this on the city? Discuss personal experiences of rain and storms on the Gold Coast.

5. Create an impression in the soil to simulate a dam and discuss the behaviour of the fl ow and how it changes.

Optional Add a section of turf or plants to the mound to illustrate the effects they have on water fl ows and erosion.

6. In groups design and complete a poster or brochure outlining the importance of the local catchments and what people can do to ensure the healthiest catchments possible.

Optional Students can research the health of the catchment by visiting:

1 http://www.healthywaterways.com.au/healthywaterways/2010ReportCardResults/catchmentResults.aspx

Curriculum links

SOSE Investigate catchments in other countries, such as Africa, Canada or India, and compare to your local catchment.


From catchment

to tapLesson plan 5Theme: Waterways and catchmentsLesson: The water highway from dam to tap

Lesson at a glance

This activity allows students to investigate the urban water cycle and water supply. They will be given the opportunity to explain the processes that enables water to travel from the catchments to their homes


Ways of working




● refl ect on different perspectives and evaluate the infl uence of people's values and culture on the applications of science








Lesson plan 5

Assessment focus

Formative assessment is ongoing throughout this unit and gives the opportunity for teachers to monitor student understandings and give feedback to their responses.

Water treatment process

Water undergoes a signifi cant treatment process as it travels from the dam to your tap to ensure that it is safe to drink and use around your home and business.

Dam inlet

Prior to the water being delivered to the treatment plants the raw water is drawn through screens located on the inlet towers at the dam. This removes any large debris that may be present. Water from the dam then travels down gravity water mains to the water treatment plants.

Alkalinity boosting

As the water enters the treatment plant, alkalinity is adjusted by adding lime and carbon dioxide. This treatment ensures the water is less corrosive as it travels through the pipelines and assists with optimising chlorine residuals throughout the distribution network. Chlorine can break down over time becoming less effective in disinfecting our water supply. Alkalinity boosting helps to ensure effective disinfection is achieved throughout our network.

Particle removal

Once the alkalinity is adjusted the water undergoes a process where suspended particles are removed. This process involves coagulation, fl occulation and sedimentation. Two primary chemicals are used to achieve particle removal, aluminium sulphate as a primary coagulant and a product know as polydadmac as a coagulant aid.

Effi cient and effective dosing of these chemicals is one of the primary responsibilities of treatment plant operators. It ensures the suspended particles that could potentially represent a health risk to the community in the raw water supply join together (or fl occulate) making their removal more effective. This process step facilitates effective removal of particles such as clay, silt and algae.

Water treatment process



Lesson plan 5

Lesson steps

■ Resource sheet: The urban water cycle (lesson 3)

■ Resource sheet: Water treatment processes (lesson 4)

Equipment

The water highway From dam to tap

1. Decide how students will use ‘The urban water cycle' resource sheet. For example, read and discuss the sheets as a class, in groups or as cooperative learning teams.

2. Select one of the options below.

● Students use the ‘Water treatment processes‘ resource sheet in groups to produce a fl ow chart of the urban water cycle. These can be compared to the resource sheet ’The urban water cycle’.

Literacy focus – option 1

A fl ow chart is a graphic organiser to describe a sequence of events or the stages of a process, using arrows to indicate the order in which to read the text.

Literacy focus – option 2

A labelled diagram includes a title and labels indicating the main features. An arrow or line is used to connect the feature and labels.

● Students use the resource sheet to add more detail to the ’The urban water cycle’ resource sheet to gain a greater understanding of the processes involved.

● Students use the ‘The urban water cycle’ resource sheet to describe the journey a water droplet takes from falling rain to a tap.

● Students use the two resource sheets ‘The urban water cycle‘ and ’Water treatment processes’ to outline the steps taken to transfer water from catchments to our taps.

Literacy focus

A procedural text is used to describe how something is done and includes instructions and directions. They include a sequence of steps and a list of requirements or materials.

Lesson at a glance

This activity allows students to investigate the initial method of treating water as it moves from the local catchments to the water treatment plants through fi ltration.


Ways of working









From catchment

to tapInformation for teachers

Lesson plan 6Theme: Water qualityLesson: Treating dirty water The Gold Coast Way




Lesson plan 6

Assessment focus

Formative assessment is ongoing and allows teachers to monitor student understandings and give feedback.


The water treatment process

This diagram shows how water is delivered to homes and businesses in your district.

Water is drawn from the catchment reservoirs. It passes through screens to fi lter out large debris and is transferred using gravity to water treatment plants.

The fi rst steps of treatment involves coagulation to destabilise particles, then transformed to larger particles by fl occulation with aluminium sulphate.

Alum dosing is part of the coagulation, fl occulation and settling process. Al2 SO4 is added to raw water to remove impurities and is the main means of colour removal.

During sedimentation gravity is used and the water is left to settle. These larger clumps of Al2 SO4 and impurities fall to the bottom so they can be removed.

Filtration is the next step. Water passes through materials that trap the suspended solids in the water. Filters are sand, gravel and charcoal (fi lter coal). Suspended solids that cannot pass through the fi lters are trapped.

The fi nal phase is disinfection. Sodium Hypochlorite is used to kill off remaining pathogens such as bacteria and viruses that were not removed through fi ltration. This is often called chlorination. After chlorination the water is safe to be transferred to reservoir tanks where it is stored before being piped to homes and businesses.

Each group

■ one litre of dirty water

■ two, one-litre beakers

■ one 1.25-litre soft drink bottle

■ fi lter paper

■ fl y screen or gauze

■ sand and gravel

■ aluminium sulphate (alum)

■ ice

■ paper towel

■ thermometers

■ gloves

■ safety glasses

Equipment

Local damreservoir

Home and business

Coagulation (chemical)

Reservoir tanks

Flocculation(physical)

Disinfection (chemical)

Sedimentation(physical)

Filtration(physical)



Lesson plan 6

Lesson steps

Treating dirty water

1. Refer students to ‘The urban water cycle’ fact sheet distributed in lesson three.

2. Highlight the processes that take place as the water leaves the dam. Note that fi ltration takes place initially at the intake tower at the dam and then as part of the water treatment plant process.

3. In today’s lesson we will be explore how to fi lter dirty water.

4. Instruct each group to use the 1.25-litre soft drink bottle, sand, gravel, charcoal (optional) and fi lter paper to construct a device to fi lter dirty water.

5. Allow time for the students to think about, design and construct a fi lter.

6. Construct a table to record observations:

Water fi ltration observations

Processes Observations

Water prior to treatment

Water after primary fi ltration

Water after addition of Alum

Water after 10 minutes

Water after sedimentation

Water after fi nal fi ltration



Lesson plan 6

Students should take the following steps and record observations:

1. Record observations of dirty, untreated water.

2. Pour the dirty water through gauze or fl y screen to simulate the primary fi ltration that takes place at the intake tower. Record what takes place during this process and the state of the water after its fi rst fi ltration.

3. Add one teaspoon of alum to the beaker of dirty water and stir. Alum is added to water as a fl occulent during one of the initial phases of water treatment at water treatment plants. Record observations.

4. Leave the samples sitting on table, don't stir or move them. Record results and continue observing the fl occulation for a further ten minutes and then note observations in the table.

5. To simulate sedimentation, allow several minutes for the suspended solids in the dirty water to settle at the bottom of the beaker via gravity. The longer the water can stand the better the result, but fi ve - ten minutes should be enough time for noticeable observations to be made and recorded.

6. Finally, pass the water through the constructed fi lter.

7. Collect cleaned water in a fresh beaker and record observations. This is the fi nal step before adding chlorine to kill off remaining pathogens.

8. Discuss the role of each step of the treatment process.

9. Compare ‘cleaned’ samples with the untreated samples of dirty water.

Optional The use of a turbidity meter to take readings and compare the samples of different groups can add to the challenge of this investigation.

Optional Students construct a fl ow chart of the processes during water treatment.

When using Alum students should wear gloves and safety glasses. Students should be reminded not to touch, drink or inhale the samples. (Alum is fi ltered out of drinking water as part of the water treatment process).

Saftey

From catchment

to tapInformation for teachers

Lesson plan 7Theme: Water qualityLesson: Water, water everywhere -desalination

Lesson at a glance

This activity allows students to investigate the future of fresh water on the Gold Coast. It is designed so students can explore how water demands are being met through the Gold Coast Desalination Plant.


Ways of working












Lesson plan 7

Assessment focus

Formative assessment is ongoing and allows teachers to monitor student understandings and give feedback to their responses to enable them to gain a deeper understanding in desalination concepts.


Of all the water on the planet, saltwater in oceans, seas and bays makes up 97 per cent. This leaves only three per cent as freshwater. Most of the fresh water is held in glaciers, ice caps and groundwater leaving only 0.3 per cent available for human consumption.

■ beakers, jars, containers

■ salt water

■ cling wrap

Equipment

Lesson steps

Water, water everywhere - desalination

1. Discuss the implications of growing demands on the local water supply.

2. What factors are infl uencing the water shortages?

3. Why are other areas not faced with the same water restrictions as we are in South East Queensland?

4. How could we meet the water demands in the future?

5. Discuss that the earth is covered in water, however 97 per cent is salt water. Of the remaining three per cent only 0.3 per cent is surface water in lakes, rivers and streams. The rest is frozen in ice sheets and icebergs, below the ground as groundwater, or in the atmosphere as water vapour.

6. Pose the focus question: is salt water always salt water and freshwater always fresh?

7. Discuss in groups ways we could convert salt water into drinking water.

8. Given the materials listed, ask the groups to design a water desalination plant that will convert salt water into freshwater.

9. If necessary draw attention to the investigations while exploring the water cycle, evaporation and condensation.

10. Draw and label the design in the science journals.

11. Describe how the desalination plant converts salt water into freshwater.

12. Devise a method of determining if the salt water has been converted into fresh water by the desalination plant.

● Students may opt for a simple taste test, observing the differences between the two.

● Others may elect to boil off the two water samples and observe for any salt residue that remains.

Optional Challenge the students to design a representation of the amount of water that is potable (for drinking) on earth. Possible ideas:

● Pie graph.

● Represent on a piece of string or strip of paper the length that would be equivalent to salt, frozen freshwater, ground water and surface water.

● Represent with marbles or matchsticks.


From catchment

to tapLesson plan 8Theme: Water futures – desalinationLesson: A drop in the ocean – distillation

Lesson at a glance

This activity allows students to investigate one of the methods of desalination. Distillation involves boiling off salt water, capturing and cooling the vapour as it evaporates to produce fresh water. Students will be able to elaborate on previous experiences to devise a distillation method for desalination.


Ways of working












Lesson plan 8

Formative assessment gives students opportunities to demonstrate learning 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 and the teaching learning process.

Seawater is drawn through an inlet tunnel that extends more

than one kilometre from the beach at Tugun. The seawater

first passes through a drum screen to remove particulates

larger than 3mm. To help remove suspended solids in

the filtration system, pH is corrected and polyelectrolyte

coagulant is added. Pre-treatment filtration involves dual

filters of sand and coal.

Desalination is a technology that separates dissolved salts

and other minerals from seawater or other salty water to

provide clean drinking water. The Gold Coast Desalination

Plant uses a process called reverse osmosis, which involves

the removal of salts and other minerals out of the water as it

moves through layers of extremely thin membranes under

high pressure. The pure water is then blended with other

drinking water supplies and distributed directly to users via

south-east Queensland’s new water grid.

Desalination – fresh water from the sea

The major benefit of desalination is that it can continue to

deliver high quality drinking water for consumption, even

during periods of drought. It also provides an alternative

source of water that will make our overall supply more

diverse and less vulnerable to interruption.

What are the benefits of a desalinated water supply?

What is desalination?

Gold Coast Desalination PlantDid you know?

The Gold Coast Desalination Plant at Tugun produces

drinking water for south-east Queensland.

The Gold Coast Desalination Plant will

produce up to 133 megalitres a day.

Assessment focus



Lesson plan 8

Concentrated seawater disposal

SEAWATER SUPPLY

PRE-TREATMENT SYSTEM

REVERSE OSMOSISPROCESS

POST-TREATMENT

FRESHWATER STORAGE

Concentrated seawater

Treated water

Mesh spacer

Membrane sandwiches

Porous layer

Semi-permeable membrane

Product tube

Fibreglass membrane element

Salt water

Reverse osmosis is the most popular type of desalination

process in the world. Reverse osmosis involves forcing sea

water through layers of specially engineered membranes

at high pressure (about 60 times atmospheric pressure) to

remove dissolved salt and other microscopic particles. The

membrane is so thin that a stack of five thousand of them

would be only one millimetre thick. The process produces

water that is of a higher level of purity than water from dams

and reservoirs (see ‘How Reverse Osmosis Works’ fact sheet).

How does reverse osmosis work?

ENERGY

RECOVERY

SEAWATER INTAKE

- Chlorination- pH adjustment- Dechlorination

PRE-TREATMENTBACKWASH

TREATMENT

RO MODULES

POST-TREATMENT

DRINKING

WATER TO

SYSTEM

SEAWATER

CONCENTRATE (BRINE)

RETURN TO OCEAN

- Chlorination- Fluoridation

High Salinity

Seawater Return

Cleaning Process(Chlorination)

PUMPS

Stages of the desalination process

1. Seawater is drawn from the ocean through a

submerged inlet tunnel to the plant.

2. Pre-treatment involves micro-filtering particles

from seawater, adjusting the pH, and adding

an inhibitor to control the build-up of scale in

pipelines and tanks.

3. Reverse osmosis forces seawater through layers

of synthetic membranes to remove salt and

minerals. Concentrated salt water is separated

and returned to the ocean.

4. Post-treatment involves stabilising the water with

small amounts of lime and carbon dioxide, then

chlorine for disinfection.

5. Desalinated water is blended with other Gold

Coast water supplies and joins south-east

Queensland’s water grid to supply homes and

industry.

Stages of the desalination process

There are more than 56,000 reverse

osmosis membranes in the plant.



Lesson plan 8


Desalination by distillation removes salts from water. If enough salt is removed (but not too much) it can used for drinking. Distillation is less common than reverse osmosis (the method used at the Gold Coast Desalination Plant) due to the high energy costs to achieve the purities for human use. Generally reverse osmosis has lower operating costs than distillation, although it has huge energy requirements.

Reverse osmosis uses great pressure to force the water through a semi permeable membrane. Gaps in the membrane are large enough for water molecules to pass through but too small for other dissolved solids (like salt).

More information about the desalination plant can be found in the previous fact sheets or by visiting the Seqwater website at: www.seqwater.com.au

What is desalination and is it used on the Gold Coast?

Desalination separates dissolved salts and other minerals from seawater or other salty water to create drinking water. When converted, it is blended with current drinking water supplies and distributed directly to users.

Desalination technologies have been used for more than 20 years. In Australia, the most common desalination process is reverse osmosis. Other processes include thermal distillation, to evaporate the salt water and collect purifi ed vapour. Electrodialysis remove salts by separating and collecting their chemical components through electrolysis (electric current).

The technology associated with desalination is rapidly improving and the cost of producing drinking water has dropped signifi cantly over the last ten years. The Gold Coast and other coastal areas are well positioned to use desalination because of their proximity to the ocean.

The major benefi t of desalination is that it can continue to deliver drinking water even if there is no rain. It is an alternative water source that diversifi es our water supply. The key challenges associated with desalination include reducing energy consumption, cost of plant construction, operation and environmental impacts.

■ bunsen burner

■ two tripods

■ gauze mat

■ buchner fl ask and stopper

■ rubber tubing

■ large zip lock bag

■ ice

■ beaker

■ salt water

Equipment



Lesson plan 8

Lesson steps

A drop in the ocean – distillation

1. Refer to the previous lesson on creating fresh water from saltwater.

2. Introduce distillation and that desalination plants around the world use one of two methods to desalinise saltwater: distillation and reverse osmosis.

3. Discuss the two methods and that Gold Coast Desalination Plant uses reverse osmosis of desalination.

4. Today the students will replicate distillation by creating a ‘still’ to separate salt from saline (salty) solution like seawater.

5. Set up equipment as per the diagram, in groups.

6. Discuss the assembly of the equipment and the processes that will take place in the still.

7. Why use the cold water?

8. Light the bunsen burner and carefully heat some saltwater in the conical fl ask.

9. Record observations.

10. Discuss the distillation method and relate this to the water cycle discussed earlier in the unit.

11. Respond to the following: ‘You may have heard that the water we have and use on earth is the same water that has been around for billions of years. You may also have heard that the water we drink is the same water the dinosaurs drank. This concept might sound crazy but use your knowledge of distillation and the water cycle to explain why this is not crazy at all.’


From catchment

to tapExcursionTheme: The catchment crawl

Lesson at a glance

This activity allows students to investigate their local area. Students take an excursion in the catchment to study the layout of the land, fl ora, fauna and human impact.


Ways of working












Excursion

Assessment focus

Formative assessment is ongoing and allows teachers to monitor student understandings and give feedback to their responses.


A catchment is an area of land that feeds water to a creek, river or other water body. As the water fl ows through a catchment it collects other substances. Therefore, the water quality produced depends on the natural qualities of the land, such as geology, soil, ecosystem and how humans use the land. A healthy catchment provides clean water, healthy soils, protective habitats, recreation, food and biological diversity.

We share the catchment with the plants and animals, and depend on it for our survival. We place competing demands on the catchment. Everything we do will have an effect somewhere else.

Gold Coast

Hinze Dam is about 15 kilometres south-west of central Nerang and supplies most of the water for Gold Coast City. 'It was built in 1976 and was upgraded in 1989 and 2011. It can now store more than 310,000 million litre. Based on average rainfall and weather patterns, it can provide 225 million litres of water per day.

The 207 square kilometre catchment includes Numinbah Valley and Springbrook Plateau. About 77 per cent is native bushland and most of this is national park. Gold Coast City Council owns more than 5000 hectares surrounding the Hinze and Little Nerang Dams, while about 15 per cent of the catchment has been developed as dairy and beef cattle properties.



Excursion

Hinze Dam



Excursion

■ worksheets

■ clipboard

■ stationary – pens, pencils

■ blank paper for drawing

Equipment

Lesson steps

1. Work from the ‘catchment crawl’ worksheet before you leave school. (overleaf)

2. Explain the types of features to look for during the drive through the catchment and to the dam.

3. Fill in the worksheet to the dam and on the way back to school.

4. At the dam, walk around the rim looking at the fl ora and fauna in the area.

5. Discuss the impact of the dam on these plants and animals.

6. Sketch maps of the catchment.

Features to be mapped may include:

● catchment boundaries

● fl ow and path of water course

● general gradients -drainage patterns of surrounding lands

● native vegetation

● parks and playing fi elds

● cleared land

● erosion

● land-use zones - residential, industrial, commercial

● location of school

● major roads

● potential pollution sources

● decide on a series of symbols to mark features on the map

7. Back in the classroom ask the following questions.

● How do you feel about the current state of your catchment?

● Did you discover any potential sources of pollution?

● What evidence was there that improvements are being made to the condition of the catchment?

● Has the fl ow or course of the creek/river been altered by human intervention? (Drainage channels, dam walls).

● Based on your catchment walk, what are some problems facing your catchment today?

● What do you think could improve our local catchment?

● In 20 years time what factors can you imagine will infl uence the state of the catchment?

● What does this mean for the way we lead our lives?



Excursion

Worksheet

The catchment crawl

On your way to the dam look for water features, human infl uences, or natural features. Identify what demands these put on the catchment and list consequences they might have for the catchment as a whole.

Examples to look for

Found in the catchmentCompeting demands

Possible consequences

Example... Farm damOff river, water storage used by people, stock and wildlife

Increase in local aquatic habitat, less water in the river system, ability for farmer to increase stock numbers

WaterExamples:

• Farm dams• Tanks• Creeks• Rivers• Wetlands• Lakes• Waterfalls

Land use/issuesExamples:• Agriculture• Industry• Recreation• Weeds• Feral animals• Urban• Development• Fenced rivers• Land degradation

NatureExamples:• Rocky outcrops• Roadside vegetation• Conservation areas• Native plants• Native animals

Documents

From catchment to tap - City of Gold Coast...From catchment to tap Lesson plan 1 Theme: Water for life Lesson: Construction of water monster Lesson at a glance This activity captures