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How We Affect WaterEducator's NotesPollutionIt is easy to dispose of waste by dumping it into a river or lake. In large or small amounts, dumped intentionally or accidentally, waste may be carried away by the current... but it will never disappear. The waste you dump in a body of water will reappear somewhere down stream, sometimes in a changed form, or simply diluted. Bodies of fresh water have a great ability to break down some waste materials, but not in the quantities discarded by today's society. The waste overload that results is called pollution, and eventually, it puts the ecosystem out of balance. Sometimes nature itself can produce these imbalances. In some cases, the natural composition of the water makes it unfit for certain uses. For example, water flowing in the salty (saline) terrain of the Prairies or gushing from mineralized springs in some parts of Canada cannot sustain fish populations. Most often, our waterways are polluted by municipal, agricultural and industrial wastes, including many toxic synthetic chemicals which cannot be broken down at all by natural processes. Even in tiny amounts, some of these substances can cause serious harm. The Great Lakes, the Fraser River, and the St. Lawrence River are seriously contaminated by such toxic chemicals. Pollution is not always visible. A river or lake may seem clean, but still be polluted. In groundwater, on which over one quarter of all Canadians rely for their water supply, pollution is particularly difficult to discern. Nor are the effects of pollution necessarily immediate – they may take years to appear. When pollution makes water unsuitable for drinking, recreation, agriculture and industry, it eventually also diminishes the aesthetic quality of lakes and rivers. Even more seriously, when contaminated water destroys aquatic life and reduces its reproductive abilities, it eventually threatens human health. Nobody and nothing escapes the effect of water pollution. Water pollution can be divided into two types: point-source pollution – waste dumped by factories or sewage plants – and non point-source pollution – otherwise called polluted runoff. Polluted runoff is what happens when you spill oil on the driveway, then hose it down; when a farmer's cows stroll through a stream; when a gardener sprays a lawn with fertilizer. Water picks it all up – oil, manure, lead, nitrogen, phosphorus – and adds it to the system. Until very recently, most pollution regulations and enforcement agencies in North America have targeted only point-source polluters. And remember, what we do affects our neighbours. Case in point: during the early 1990s, a study of fish from Lake Laberge in the Yukon Territories turned up a variety of chemicals, including the insecticide toxaphene, widely used in Russia. Scientists determined that the insecticide probably blew east from Russia, and was raked into Lake Laberge by the rain. Acid Rain: Byproduct of the Industrialized WorldAcid rain is a global phenomenon, in which Canada ranks high as both a contributor and an unwilling victim. Like all industrialized nations, we discharge millions of tons of sulphur dioxide and nitrogen into the atmosphere every year through industrial and automobile emissions. Some of these gaseous emissions return to us in the form of acid rain, causing serious environmental damage. Moreover, since precipitation patterns are affected by winds and other meteorological influences, acid rain doesn't necessarily fall on the heads of those who are creating it. Like global warming, caused by the "greenhouse effect", acid rain knows no international boundaries. It simply falls where weather patterns take it, affecting the environment wherever it lands. Because of the abundance of fresh water lakes in Canada, the effects of acid rain are easily documented, and we are finding ourselves facing considerable ecological and economic strains as we wrestle with this problem. Magnitude and Cost
What is Being Done?Governments of industrialized nations the world over are taking steps to regulate the emission of industrial gases causing acid rain. However, the economies of these countries, including Canada, require continued industrial growth to sustain our standard of living. What Can We Do?Automobile emissions account for a percentage of the acidic gases released into the atmosphere. By taking public transit where and when it is available, forming car pools and riding bikes or walking, the public can play an important role in cleaning up the atmosphere. This is especially true in North America and Europe, where the use of automobiles has become a major social and environmental problem. We can also write to our government representatives and put pressure on our industries to increase regulations and research aimed at decreasing acidic gas emissions. Are We Changing the Earth's Atmosphere?Earth's atmosphere is a mixture of clear, natural gases that extends approximately 100 kilometres over our heads. The atmosphere is what we breathes, and is the cradle from which our different climates spring. It creates the weather patterns that influence our lives and activities. And it is a finite resource. A major international conference, "The Changing Atmosphere", held in Toronto in 1988, warned the world that ongoing industrial and transportation pollution of the Earth's atmosphere must be curbed or there will be serious consequences to life on this planet. Experts at the conference predicted that because so much pollution has entered the atmosphere already, climatic changes are inevitable. They called for an immediate 50% reduction in carbon dioxide gas emissions world-wide, to moderate the severity of these changes. The Greenhouse EffectThe conference made it clear that the potential of man-made chemical substances to bring about a change in the Earth's climate, affecting the distribution of biological life forms in the very near future, is as big a threat to our continued existence as the nuclear arms race. In fact, the general warming of the Earth's climate, caused by the build-up in the atmosphere of greenhouse gases, such as carbon dioxide and methane, has reached such critical proportions that the greenhouse effect and global warming have become topics of world-wide concern. The Greenhouse Effect on CanadaStudies by Environment Canada and several Canadian universities suggest some of the following implications of global warming on Canada. Most of these implications will directly affect our water resources.
Quantity, Quality and ConservationHow does saving water help water quality? Water saved is water that does not end up in the wastewater stream and require treatment. Less wastewater in the sewage treatment plant also means that the plant has a better chance of doing the job it was built to do. How do we begin to conserve water at home? The first step is to identify where we use water in our homes. Then we must decide on what to do to reduce the amount of water we use, either by eliminating wasteful practices and habits or by improving the efficiency of our water-using fixtures and devices. Since we waste so much, this should really be a relatively easy and painless process. The prime area to target in your initial efforts at water conservation is the bathroom, where nearly 65% of all indoor water use occurs. ActivitiesWhat is Acid Rain?Grade 4 – Science PurposeWhat does acid rain look like? is sludgy and gross? No – and this is part of the problem with detecting certain types of pollution – acid rain looks clear. As a matter of fact, lakes that have been destroyed by acid rain tend to look clear and clean, mainly because they no longer support plants or algae. Neither do they support fish, birds, or animals. Here's a simple way to show younger students what acid rain might taste like to a fish or plant.
Have the students get a glass of drinking water. Smell it, feel it and taste it. What does it taste like? Would they like to swim in it? Do they think a plant would like to drink from it or grow in it? If any of the students have pet fish at home, ask them how the fish like the water to swim in. Pour approximately one tablespoon of vinegar into each student's glass. Explain that vinegar is not what is actually causing acid rain, but the effects of the water are similar. Ask them to smell, feel and taste this new, acidic water. Would they like to swim in it? What do they think it would feel like in their eyes? Could plants grow in it or be watered with it? Would a fish like to swim in it? Building a Better PlanetGrades 4, 5, 6 – Social Studies PurposeStudents will begin to develop critical thinking skills. There is a critical link between land use and the protection of water and other natural resources. Groundwater quality is directly linked to water pollutants from a variety of land use practices – disease-causing organisms such as bacteria enter the water through sewage and animal waste; synthetic organic compounds such as those found in industrial, household and agricultural chemicals; inorganic compounds found in water from acid rain or from mining; radioactive substances; plant nutrients from agricultural and home use; sediments from erosion. Land management practices have been created to protect our resources by developing regulations pertaining to solid waste disposal and solid waste treatment and regulating industries and what industry is allowed to dump into the water supply. In parts of North America, land use policies have been in effect for over one hundred years. Different groups are involved in planning land management policies: developers; environmentalists; farmers and other private landowners; private citizens; public officials; the list goes on and on. Planning land management policies involves all sorts of different considerations: traditional land use; traffic use; environmental concerns; zoning regulations, etc. Materials
ProcedureDiscuss land use and the implications of land use on the environment. Hand out the Populous River Valley information sheets. Students will create members of the task force and represent each of the following groups: surface water irrigators, groundwater irrigators, wetland protectionists, wildlife advocates, recreations interests, Star City officials, and the downstream Province of Misery. ExtensionInvite a land planner, and/or an engineer, and/or an environmental advocate to speak to your class about their viewpoints regarding land planning and management activities. Water Uses WorksheetGrades 4, 5, 6 – Mathematics, Social Studies PurposeStudents will develop an appreciation for the amount of water they use daily and strategize a method of reducing their personal water consumption. There is little danger of North Americans running out of water. There is a very real danger, however, of running short of pure water. MaterialsProcedureInstruct the students to study the two charts on the Water Uses Worksheet. Ask that they keep the sheet with them for one day, marking it each time they use water. Students may use the back of the paper for mathematics. Students are to be reminded that the amounts shown are estimates only, not an exact measure of how much water is used. Some amounts seem extraordinary, but are real estimates: for example, the figure shown for "getting a drink" assumes that people allow the water to run from the tap to get cold before they drink. The chart entitled "Your Share of Your Family's Water" helps students estimate their share of the daily household water use. ExtensionAsk students to imagine ways that they can measure their actual water use. Ask students to plan and then to implement a strategy to decrease their wasteful use of water. Water Information SheetGrades 4, 5, 6 – Mathematics, Social Studies PurposeStudents will learn some simple ways to save water in their homes after studying their family's total water usage in a week. MaterialProcedureDistribute handouts and enclose a letter to parents or guardians, explaining the activity. Students may want to post the information sheet on the bathroom door or near the kitchen and encourage family members to mark it when they use water in each of the categories. After one week or fuse, students are to return the sheets. You may then incorporate the sheets into several math lessons. ExtensionsHave the students "invent" water saving devices for the various uses of water throughout their homes. Have the students plan realistic strategies for conserving water in their homes. English Language Arts Protect the DolphinGrades 4, 5, 6 – Science, Social Studies, Physical Education PurposeStudents will evaluate how the actions of a group can affect the entire ecosystem. Many countries are concerned about the future of dolphins and whales. In the last few years, many of these aquatic mammals have been killed by fishing nets or by people who hunt them. Many are now nearing extinction. It is important that – while this is a game – the teacher speaks with the class after the game is over to discuss what can be done to save these mammals. Materials
ProcedureSeveral children are chosen to act as dolphins, several are commercial fishers with their nets (dodge balls), and the rest of the class serve as dolphin guards. The dolphins can not run, but may walk quickly. The protectors can run and catch the ball to ward off the throws of the fishers. When a ball hits a dolphin, the dolphin is out of the game, and sits on the sidelines. The fishers stand in the middle of the group and can only rotate – they cannot chase a dolphin. The fishers throw the balls to try to hit a dolphin. Students should rotate to experience all points of view. The game may be adjusted so there are more dolphins than protectors, or more fishers and dolphins than protectors. After all students have played, gather the class to discuss their feelings about the game. How did it feel to be a dolphin? What did the dolphins feel like when the ball was headed their way but they couldn't escape? How did the dolphins feel about their protectors? About the fishers? How did the protectors feel? How did it feel to be a fisher? ExtensionsWhat can the class do to stop dolphins from being caught? Several years ago, children were instrumental in getting tuna companies to label their tuna indicating that dolphins were not harmed in the fishing of the tuna. Have the class research commercial ocean fishing. Ask a local fisher or a member of the Department of Fisheries and Oceans to speak to the class about humane fishing practices. Research dolphins and/or other endangered marine species. Write a story or poem about being a dolphin. To Dam or Not To DamGrade 6 – Social Studies, English Language Arts PurposeStudents will evaluate the potential positive and negative effects of constructing a dam on a river. BackgroundThe town of Big Sky, population 22 000, is located along the Scenic River. The people of Big Sky and other towns nearby are concerned with the recently developed Scenic River Dam proposal. The Big Sky Metropolitan Association proposed the construction of the dam as a result of a study they commissioned. They want to ensure the continued growth of the suburbs of Big Sky Metropolis – and the suburbs need water. The study says that the most efficient way to provide the suburbs with water is by constructing the Scenic River Dam. The Scenic River Dam will also generate hydroelectricity for the local communities. The Scenic River Dam will be located about 40 kilometres from the town of Big Sky. Construction of the Scenic River Dam will take up to 25 years to complete, and will create a 7 300 hectare reservoir on the Scenic River. Wildlife will be affected in the following ways:
Environmentalists and dam engineers know that the water levels below the dam will be very low for at least part of the year. Water going over the dam will drop a very long distance. Another consideration is that very cold water from the bottom of the dam will be released into the river below. Other environmental impacts include the loss of a white-water section of the river that is now used by private and commercial rafting, kayaking and canoeing enthusiasts. Residents of Big Sky and the surrounding areas will also experience an increase in their power bills of about $10 a month for the next 30 years to pay for the new dam that will, eventually, generate hydroelectricity. While the people of Big Sky and surrounding communities are concerned about the potential for problems the Scenic River Dam will create, they are also interested in the benefits the dam will bring their area in terms of jobs and development. They know that the dam will provide work for approximately 2 000 workers during its development, and that it will employ 200 people permanently when the dam is complete. They can imagine how these new jobs will positively affect their community. They also know that the hydroelectricity the dam will generate when it is completed will probably be less expensive for them to pay for than the electricity they buy now, which is generated by the burning of fossil fuel. The hydroelectricity will also be more cleanly produced than the electricity that is generated now. ProcedureDivide the class into groups of three students. Ask the students to individually choose a role from the list provided. They should prepare for their individual roles by writing background for their character of at least five sentences long. Have the students share, in groups of three, the position of each of the characters they have selected. While one student is speaking about their character's position, the other students are recording what is being said. Discuss as a class the pros and cons of constructing the dam. The students discuss and record the following:
You may choose to hold a mock public hearing with class members playing out these roles, or to have the class produce and videotape a play. Choose from the following list of characters:
Down the HillGrades 4, 5, 6 – Science PurposeStudents will learn about water drainage patterns, discover the geographic interrelation of different landscapes and explain how pollution might enter rivers and lakes. Students will develop an understanding of point source and non point source pollution. Students will create a simple watershed model, discovering hills, rivers and lakes from a bird's eye view. They add rain to the model and describe water's flow pattern. This activity can be used to introduce the topic of water pollution. Materialsfor one batch of salt dough – teacher prepared
Mix and heat ingredients until a ball forms.
ProcedureBreak the class into small groups and have each group construct a simple watershed relief map in their pans. One end of their landscape should be higher than the other, and part of the landscape should include a Y-shaped valley, with the tail of the "Y" ending in a depression. You can use the diagram at right for a model. Explain that water runs downhill. River water is water that has drained off the surrounding ground and water that comes from underground. Have students sprinkle rain over their model and observe the path of the water as it runs through the model. Where does the rain collect? Explain that areas where water has collected become bodies of water (lakes, ponds, streams, rivers, etc.). Let the "rain" continue until the pan begins to fill. Explain that if water has no way to be carried off, then flooding occurs. Flooding can also occur when water cannot be carried off quickly enough. Sprinkle a bit of KoolAid on the model, and explain that the KoolAid represents chemicals that come from products we use daily. Ask the students to name some of the products the Kool Aid might represent. Sprinkle water on the model, and explain that now it is raining again. You've just demonstrated "runoff". Discuss how pollutants enter the water and are carried by the water. Discuss point source pollution and non point source pollution. Simulate these by pouring coloured water into the river at one point in the model (point source) and by raining coloured water (non point source).
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