Water Quality Student Reader

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Student Readers

What is the Water Like in Our River?

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Learning Set One

Student Reader

CLOSER LOOK AT OUR RIVER Think about what is would be like to have a boat as your only means of transportation. The roads you use would be waterways, rivers and streams. Hard to imagine isn’t it, especially with all the cars and buses that crowd our streets. Rivers and streams were once a main form of transportation to many parts of the country before cars and trains. So what do we use rivers for now? do we still need rivers? How do they affect our lives?

1. Make a list of at least 5 ways in which you use rivers. __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 2. Now, think about some rivers around your city where you live. For instance, Detroit sits in among some very important waterways. In fact, rivers are one of the reasons that cities like Detroit were first settled 300 years ago. list as many bodies of waters (lakes, streams or rivers) that you can think of that are near Detroit or Grand Rapids. __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 3. Detroit, like Grand Rapids, is a city affected by water in many ways. One body of water in Detroit is the Rouge River, which is similar to, though smaller than, the Grand River. The following is an article about an event that happens every year right around this time on the Rouge River. Take a guess of what happens to the Rouge every spring when it rains and the snow melts? __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

Student Reader/Learning Set One

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Hines Park floods---Naturally April 8, 1998 The Detroit News Summary of an article by Gene Schabath

April showers bring May flowers, and the storms bring flooding along Hines Park Drive. Hines Park Drive closes nearly monthly each year because of flooding, mainly between Ann Arbor Trail and Outer Drive. It’s all nature’s design. There isn’t much man--- or more specifically, road or sewer builders-- can do about it. “A lot of times, when people see Hines Park flood again they assume something is wrong the way the whole park is configured,” said John Roach, a spokesman for Wayne County Department of Public Services. “But in reality, it’s natural flood plain and has been for centuries.” William Gaston, who lives in Garden City near the park, agreed. “It floods occasionally, but that’s what it’s there for.” Gaston said. As for the recreational value of the 17 mile long Hines Park, Gaston said, “it’s a nice park,” especially because Wayne County Sheriff’s Department eliminated a drug problem that cropped up years ago. Nancy Darga, chief of design with the Wayne County Parks Division, said the flooding of Hines Park had increased since she has started working for the parks agency in 1977. “It’s because of the building boom, and (the fact that) so much storm water gets poured in to the upper reaches of the Rouge River,” Darga said. Hines Park, located along the middle branch of the Rouge River, was acquired as park land in 1928 by Wayne County, but the idea for turning the flood plain in to recreational land came from Henry Ford, Darga said. Ford started the initiative about 15 years earlier because he was upset over sewage from other communities floating by the family home along the Rouge River at Fairlane, which is where Dearborn is now. 4. Questions to think about: Maybe you have been to a park like Hines Park (including Millenium Park or Riverside Park in Grand Rapids), or seen a different river flood its banks on television? Do you think it is natural for a river to flood? Why do you think rivers flood? __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

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Student Reader/Learning Set Two

5. Water Quality In class you examined a variety of jars of water. You compared them and discussed the water quality of each jar. As a class you talked about what criteria to use in determining water quality, you might have used color, smell or clarity (how clear the liquid was). How do you think a jar of water from Hines Park flood would compare to the jars you studied? What might you do to determine what the water quality is like when it floods at the Hines Park? __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 6. In the next couple months you will answering the question ”What is the water like in our river?” Using this question you will explore the quality of the water and land that surround your river. You will need to develop questions, just like scientists use, to help you learn more about your river. Questions help scientists organize their thoughts, formulate their hypothesis and continue with their investigations. The questions you develop will help you explore how the water and l and affect your river and the animals that live in it. Remember good questions should: - interest you - will not have a simple yes or no answer - require many different resources to answer - relate to the larger topic - help you understand science - need data to be answered completely Think back to the article you just read, what might some questions you could ask to help you understand why the Rouge River floods at Hines Park? __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

Student Reader/Learning Set One

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Learning Set Two

Student Reader

WHERE IS MY RIVER LOCATED?

Think back to when your class visited the river or took the virtual tour. You probably only saw a small area of your river. Imagine what other parts of your river might look like both up and down stream. They each would probably look different. Remember one thing all parts of the river and surrounding land have in common is that they all are part of the same watershed. What’s a watershed?

A watershed- it’s the area of land that catches rain and snow that drains or seeps into marshes, rivers, lakes, streams or ground water. It is a land area that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge. Large watersheds, like the Great Lakes watershed, contain thousands of smaller watersheds. Figure 1. Areas of a watershed The dotted lines show where the boundaries are for this area’s watershed. Notice that there are three separate directions in which the water can flow. Each of these areas would be it’s own individual watershed. However, they are all part of the larger watershed that drains in to the river.

Watersheds come in all shapes and sizes. They cross county, state and national boundaries. No matter where you are, you’re in a watershed! When you think of a watershed, think of land “shedding” the water. Watersheds include both the water and land. Where is your river’s watershed?

Grand Rapids is nested in a large watershed called the St. Lawrence/Great Lakes watershed. Within each watershed, there are smaller watersheds.

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Figure 2: St. Lawrence/Great Lakes watershed. This is a satellite image of the St. Lawrence/Great Lakes watershed. It includes each of the 5 Great Lakes.

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Source: Rouge River National Wet Weather Demonstration

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Look at the map to the right and try to guess what body of water your river drains into? G- Grand River 1 Lake Michigan 2 Lake Superior 3 Lake Huron 4 Lake Erie 5 Lake Ontario

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5 G 4

The rivers in and around west Michigan are found in the Lake Michigan watershed, located in the smaller oval marked on the picture above. The Lake Michigan watershed is part of the Great Lakes/ St. Lawrence watershed, marked on the picture as the larger oval. Figure 3: Illustration of an area that has both high and low regions, and pooling water.

Figure 2: Representation of a watershed with high and low lands.

Who Creates a Watershed?

H

Key L

L

H - high land areas

L - low land If you have ever been on a H areas waterslide, you know that L water flows from high eleva- water L H tions to low elevations, which pools creates a slope. In class, you built your own watershed with tall, medium and small objects that resembled different elevations then covered them with paper. When you sprayed your watershed with water, you saw water go from higher areas to lower areas, following the slope of each change in elevation. Similar things happen in the real world. On a large scale, even though we might think Michigan is flat, it has areas of different elevation. Maybe you have sled down a hill, or biked up one. Hills are created by land at different elevations, high and low which creates a slope in the land. The land throughout Michigan is at a higher elevation than the elevation of the Great Lakes. This is how Michigan’s water in rivers and streams get to the Great Lakes and eventually makes its way to the Atlantic Ocean, through the St. Lawrence River.

Why does water flow from high to low areas? The same reason that causes your pencil to fall to SR

Student Reader/Learning Set Two

the ground if you drop it: gravity. Gravity is the force that pulls everything toward the center of the earth. Water flows to the lowest point because gravity pulls water to the lowest elevation.

What do watersheds look like?

Maps are important tools in determining the flow of rivers. You looked at a topographic map during class. Figure 4: Topographic map

Topographic maps show the elevation of different land features. The following is a topographic map of Michigan. Even though you might think Michigan is flat it actually it has a variety of elevations. This topographic map (left) has the high, H, medium, M and low, L areas marked. What do the different colors (different shades of gray) on the map represent? _________________________________________________ _________________________________________________ _________________________________________________ _________________________________________________

___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ Add 10 different arrows to the topographic map indicating the direction the water would flow during a rainstorm.

Think back to the beginning of this reader, do you remember which lake you guessed your river eventually drained into? Look at the profile of the Great Lakes on the next page of this reader (Figure 5) to check if you were correct. It shows the elevation of each of the Great Lakes and the elevation at which each river enters its corresponding Great Lake. Both Lake Michigan and Lake Huron are at a lower elevation than Lake Superior. So, water from Lake Superior either enters Lake Michigan or Lake Huron. Water will eventually make its way to the St. Lawrence River.

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St. Mary's River

Detroit River

Welland Canal

183.2 m. 176.0 m Lake Michigan

Lake Superior

176.0 m Lake Huron

St. Lawrence River

173.5 m Lake Erie

74.2 m Lake Ontario

Sea level Atlantic Ocean

Figure 5: Great Lakes profile.

Use Figure 5. to answer the following question: If there was an oil spill on the St. Mary's River, which of the Great Lakes would be affected? Where would the oil end up? Why? ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________

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Student Reader/Learning Set Two

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Learning Set Two

Student Reader

LANDCOVER AND USES: HOW DO THEY AFFECT OUR RIVER? In class, you observed and experimented with a model of a stream. The sand and soil represented the land. The stream you made with your finger represented a river. As you let the water flow into your model, you made observations about how the water flowed. You also observed how the water changed the shape of the land. Additionally, you changed parts of your stream table to resemble different types of land uses such as urban areas and grassy areas. With the change of land cover, you explored the affects each of changes had on your stream. Erosion and Deposition Affect on the Land We have all seen it rain. During a heavy rainfall, water in a stream flows fast and will pick up more dirt. As water flows against the bottom and sides of the river channel, it removes more dirt, sand, soil and debris. Scientists call the "removal of dirt" erosion. When water slows down, dirt found in the river drops out of the water. Scientists call the dirt and soil “dropping out" of water, deposition.

Erosion is a process where the earth!s materials are loosened and removed. Deposition is the setting down of earth!s materials on to another area. In your stream table, you may have noticed sand being deposited at the end of the stream. How did it get there? The flowing water eroded the sand and deposited it at the bottom on the stream table, this is an example of deposition. 1) Think about the stream tables, what is one variable that might affect the amount of deposition in a river? Describe how that variable affects the amount of deposition in the river. 2) What is one variable that might affect the amount of erosion in a river? Describe how that variable affects the amount of erosion in the river. How does land cover affect erosion?

You used stream tables in class to see how deposition and erosion change with different land covers. You modeled bare soil, urban land covers, and grassy areas. Remember that erosion and deposition happen naturally, but can become a problem for the plant and animal life when humans alter the land and cause so much erosion and deposition that the natural landscape cannot handle. The following are ways in which humans have changed the land and examples of how that can affect the nearby rivers. Student Reader/Learning Set Two

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Rural Land Use

Much of Michigan's economy was built on farming. Today many large areas of land are still being cleared to plant fruits and vegetables. As trees and grasses are removed for farms and houses, soil can wash away and be deposited into the lakes, rivers, and streams. This can eventually alter the flow and landscape of the rivers. In addition to soil and dirt being washed into streams, there are other variables related to farms that affect water quality in streams. Many farms rely on chemicals to kill insects and weeds. They use fertilizers to help the plants grow. When you sprayed colored water on your stream table, you modeled how fertilizers and pesticides are sprayed on crops. How did the colored water flow when you sprayed it on your model? You may have seen that some of the colored water was absorbed into the ground, and the rest moved across the land into the river (figure 2). The process when the water runs across the land and is not absorbed is called run-off. Figure 2: Erosion and run-off with bare soil. Chemicals and fertilizers used to help crops grow can eventually drain into a river. This is an example of run-off. This may be harmful to aquatic animals and plants. Today there are other less harmful and more natural ways of fertilizing and protecting crops from pests, for example crop rotation and natural fertilizers.

Run-off is any liquid that flows across the land surface into streams and rivers. Life in the City: Urbanization

When you built an urban area for your stream table model, you might have used plastic to represent pavement, preventing the water from absorbing into the ground. You also used plastic blocks to represent buildings. During this part of your stream table model, run-off was going over the plastic surfaces and either formed a puddle or washed into the stream. This creates a quick flash of water in the stream all at one time, this is called a flash flood. Figure 3: Runoff with urban land cover/uses. Rain and snow collect on paved surfaces. Motor oil and salt can be washed with the water into a nearby river, which can cause harm to fish and plant life.

Run-off from rooftops, roads and lawns eventually flows into nearby streams, lakes, and rivers (figure 3.) This water may contain household chemicals used for cleaning or fertilizers that are used to make lawns green. Other sources of urban pollution include salt and oil. Salt is used to melt ice from the roads. Additionally, oil can often leak from cars. These products get washed from roads and can end up in a river. 3.) How might the salt and oil affect the river and its organisms? SR

Student Reader/Learning Set Two

Grass land

When you created a grassy and plant covered area on your model, much less run-off occurred. So, where did the water go? The grass and plants absorbed the water (figure 4). Scientists call this absorption. Plants, like grasses and trees, can act like a sponge. They absorb rain and snowmelt and then release it over time. This provides a steady supply of water to the ground and nearby streams. Figure 4: Absorption with grassy and plant covered land areas. Large areas of plants and grass absorb rain and snow, decreasing erosion and run-off in rivers, lakes and streams.

Absorption is the process when the ground, often covered with trees and grasses, soaks up the water preventing the water from becoming run-

off.

4.) Write a description of what happens to the water when it rains in your neighborhood. The paragraph should include where the rainwater goes, where the rain is absorbed, where rain might run-off and where you think most of the water ends up going. Pollution Sources

Pollution sources are divided into two groups depending on how the pollutant enters the body of water.

Point source pollutants come from an identifiable point and directly discharge into rivers and lakes. Non-point source pollutants come from many sources that are difficult to identify, they often enter the river in run-off from large land areas Sources of point source pollutants

• Pipes • Leaking barrels that contain chemicals such as pesticides and weed killers • Smokestacks • Sewage treatment plants

Student Reader/Learning Set Two

Sources of non-point source pollutants

• • • • •

Golf courses & homes that use fertilizers Sewer grates Roads Run-off from farm fields Construction sites

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Both point and non-point source pollutants can be harmful. However, because the source is known, point source pollution can be controlled. For example, if the pollution from a smokestack exceeds safe levels, the responsible company or person can be contacted and asked to reduce its amount of pollutants. Strict laws have been passed to limit the discharge from point sources. Non-point sources of pollution are much more difficult to control. It is hard to determine who or what is responsible for any Non-point source pollutant. Non-point source pollutants can originate from a very large land area such as an entire watershed. For example, run-off-containing fertilizer used on lawns in suburban areas is a non-point source pollutant that can pollute a river or stream. The law does not regulate non-point sources of pollution as strictly as point sources. An important way to control non-point source pollution is for individuals to reduce the amount of pollutants they use in and around their homes. The people below are taking care of their lawn and car, but they are also doing many things that can pollute the water in their community, such as the stream beside their house.

Figure 5: Taken from EPA’s website: http://www.epa.gov/kids/whatswrong.htm

5.) Look at the drawing above and choose three examples of pollution and explain how each action will affect the water quality in the river. Be sure to explain if the pollution is point or non-point source pollution. SR

Student Reader/Learning Set Three

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Learning Set Three

Student Reader

TESTING YOUR WATER Testing procedures are found at the end of this reader.

In class, you have been investigating the question, "What is the water like in our river?" You have learned about your watershed and about how erosion and deposition can alter the shape of a river. But how will you know if the water is safe for swimming? Or, drinking? By performing water quality tests you can tell if water is safe to touch or to drink. These tests will also determine if the water is acceptable for living organisms such as fish, plants and other small creatures. These organisms are an important part of the food chain; they help us decide whether the river or lake is healthy or if it needs help. When humans add pollutants to the river, they can change the health of the river. There are two main sources of pollution. Point source pollution enters the water from a specific place. They include paper and pulp mills, meatpacking plants, food processing industries, and wastewater treatment plants. We can test water coming out of a pipe and see if it contains harmful material. Nonpoint sources of pollution come from large areas of land and do not have a direct identifiable source. They include urban runoff, pet wastes, lawn fertilizers, leaves, and agricultural runoff. When scientists test the water quality, they measure specific properties of the water. For example, they may take the temperature of the water and use that as an indicator of how healthy the water is. You will test your particular section of the Rouge River watershed (or whichever river you are investigation). The results of these tests and your knowledge of watersheds will be used to determine the overall water quality of a particular section of the river.

The following pages will give you information about 8 of the water quality tests. They are: dissolved oxygen total phosphate biochemical oxygen demand nitrates fecal coliform turbidity pH temperature 1. What is "water quality"? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Student Reader/Learning Set Three

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2. In the following list, which are point-source pollutants and which are non-point source pollutants. Explain your reasoning. Golf course Outlet pipe

Barrel of gasoline Acid rain

Lawn fertilizer Factory

_________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Dissolved Oxygen

Dissolved Oxygen (DO) is important for healthy rivers. All aquatic animals need oxygen to survive. Testing for DO can help us determine the health of a body of water. Although an oxygen atom is present in every water molecule (the O in H2O), animals cannot use this oxygen because it is strongly bonded to the hydrogen atoms. Aquatic organisms must have a continuous supply of oxygen gas (O2) dissolved in the water. Dissolved oxygen is an oxygen molecule (2 oxygen atoms bonded together, O2) surrounded by many water molecules. In the diagram below, how many dissolved oxygen molecules (O2) are in the water sample?

H2

H2 H2

H2

H2 H2 H2

0

H2

H2

H2

H2 H2

H2

0

H2

0 H2

H2

H2

H2

H2

H2

H2

Figure 1. This illustration demonstrates how oxygen molecules can be dissolved in water.

You should have found 3 dissolved oxygen molecules in the diagram. It is similar to dissolving sugar in water. Solid sugar particles can dissolve. When dissolved, the sugar spreads throughout the water. Similarly, gaseous oxygen molecules dissolve and are spread throughout the water. Most of the dissolved oxygen in water comes from the atmosphere. Waves and tumbling waters mix atmospheric oxygen into water. Through photosynthesis, algae and rooted aquatic plants are also a source of dissolved oxygen. Waters with consistently high dissolved oxygen levels are most likely healthy and stable environments. Natural and human changes to the aquatic environment can affect the amount of dissolved oxygen available to the organisms. SR

Student Reader/Learning Set Three

Dissolved oxygen is measured in units called parts per million, or ppm. For example, if you took a water sample that had a DO content of 8 ppm, it would mean that for every 1 million molecules, there would be 999,992 molecules of water, and 8 molecules of oxygen. The amount of dissolved oxygen needed to support aquatic life depends on the type of animal being considered. Fish cannot live in water with dissolved oxygen content that is less than 4 parts per million (see Figure 2). That can be difficult to visualize, so let's assume that a sample of water is represented by a million pennies stacked one on top of another. The stack would rise 1 mile high! Just 4 pennies of this stack would represent the minimum level of dissolved oxygen needed to survive. It is very small, but an essential quantity. Figure 2. Fish depicted with dissolved oxygen.

Out of 1 million parts of water, this fish only needs 4 parts to be dissolved oxygen. Cold water can hold more dissolved oxygen than warm water. Water at 28oC can hold up to 8ppm dissolved oxygen. Water with a temperature of 8oC can hold up to 12 ppm of dissolved oxygen. Dissolved oxygen is measured in a unit called percent saturation. This is how full the water is with dissolved oxygen. For example, if water at 28oC has 8ppm of dissolved oxygen, we say it is 100% saturated. That is as much dissolved oxygen water at that temperature can hold. If that same sample of water had 4ppm of dissolved oxygen, it would be 50% saturated. High levels of bacteria from sewage pollution or large amounts of rotting plants can cause the percent saturation to decrease. This can cause large changes in the dissolved oxygen levels throughout the day. It will affect the ability of plants and animals to live. 3. What is dissolved oxygen? Draw a picture to represent your explanation. _________________________________________________________________________________ _________________________________________________________________________________

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4. Why is dissolved oxygen beneficial for organisms that live in the river? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Biochemical Oxygen Demand

Living organisms need oxygen to survive. Biochemical Oxygen Demand (BOD) is a measure of the dissolved oxygen used by bacteria as they breakdown waste. In slow moving and polluted rivers, bacteria use much of the dissolved oxygen. This prevents other organisms from using the dissolved oxygen. Organic materials are things that are or once were alive. This includes leaves, fish, birds, plants, algae, and humans. These living organisms eventually die and begin to decay. The bacteria that breakdown these materials use up the dissolved oxygen in the water. Fertilizers contain nitrates and phosphates that help plants grow. This is both good and bad for water quality. It is good because as river plants grow, they photosynthesize and produce oxygen. It is bad for water quality because when the plants die, bacteria break them down and use up the dissolved oxygen in the water. Figure 3. Decomposing leaf litter.

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Figure 3. Decomposing Leaf litter

Leaves and other organic debris fall to the bottom of the river and are decomposed by bacteria. The bacteria use dissolved oxygen in the water. In rivers where bacteria use a lot of the dissolved oxygen, organisms that are more tolerant of lower dissolved oxygen levels may increase. Organisms that are intolerant of low oxygen levels will either leave or die.

5. What is biological oxygen demand? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ 6.What would make the biological oxygen demand increase? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________

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Student Reader/Learning Set Three

Temperature

Temperature is very important to water quality. Temperature affects the amount of dissolved oxygen in the water, the rate of photosynthesis by aquatic plants, and the sensitivity of organisms to toxic wastes, parasites, and disease. As the temperature increases, the amount of plant growth increases. This is good because it adds dissolved oxygen to the water, but plant growth can increase too much. The plants will eventually die and decomposing bacteria will use up the dissolved oxygen. Heated water from industrial operations is often added to rivers. This is known as thermal pollution. It can cause temperature changes that threaten the balance of the river’s ecosystem. For example, if the water gets too hot, certain organisms that live in the water may die. If aquatic animals are stressed by large temperature changes they are more likely to become prone to diseases and die. Most aquatic organisms can live within a certain range of water temperatures. Some organisms prefer cooler water, such as trout, while others need warmer conditions, such as carp. As the temperature of a river or lake increases, cool water animals will leave (or die) and warm water animals will replace them. Most organisms cannot survive in temperatures of extreme heat or cold. 7. What is thermal pollution? _________________________________________________________________________________ _________________________________________________________________________________ 8. Why is it unhealthy for a river system? _________________________________________________________________________________ _________________________________________________________________________________ Total Phosphate

Just like dissolved oxygen, other dissolved substances can be found in water. One substance is phosphate. A small concentration of phosphates is beneficial for the health of a river. Phosphate is needed for plant and animal growth. However, high levels of phosphates in the river can lead to overgrowth of plants, increased bacterial activity, and decreased dissolved oxygen levels. Excess phosphate is found in living plants and animals, their wastes, and their remains. Algae and other aquatic plants easily take up phosphates. Algae need only a small amount of phosphate to grow. This means that excess phosphate can cause large amounts of algae to grow, called "algal blooms". Soil erosion contributes to the formation of algal blooms by bringing phosphates (in the form of fertilizers and detergants) to the water. 9. Why is too much phosphate unhealthy for the river? _________________________________________________________________________________ _________________________________________________________________________________ Student Reader/Learning Set Three

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10. What are the sources of phosphate? _________________________________________________________________________________ _________________________________________________________________________________

Nitrate

Nitrate is a nutrient needed by all aquatic plants and animals to survive. Some nitrate is good. Excess nutrients such as fertilizer run-off into the river. This causes many plants to grow and eventually die. When they die, bacteria decompose the materials. Because the bacteria use oxygen from the water, the amount of dissolved oxygen available in the water decreases. The decompostion of dead plants and animals and the excretions of living animals release more nitrate into the water system. Sewage is the main source of excess nitrate added to natural waters. Sewage can enter the river through sewage outlet pipes. These outlet pipes are opened during heavy rains to prevent flooding of wastewater treatment plants. Fertilizer and agricultural runoff also contribute to high levels of nitrate. 11.Why is too much nitrates unhealthy for the river? _________________________________________________________________________________ _________________________________________________________________________________ 12.What are the sources of excess nitrates? _________________________________________________________________________________ _________________________________________________________________________________

pH

Another factor that influences the health of the river is pH. pH is a measurement of the acidity of water. Liquid substances can be measured and given a value on a scale from 0-14. A value of 0 is very acidic and 14 is very basic. The pH of neutral water is around 7.0. Industrial waste, agricultural runoff, or drainage from improperly run mining operations can affect pH. Additionally, nitrogen oxides and sulfur dioxide from cars and coal power plants are emitted into the atmosphere to form nitric acid and sulfuric acid. These acids combine with moisture and fall as acid rain. Some aquatic organisms are adapted to a specific pH level (see Figure 10). They may die if the pH of the water changes even slightly. Other aquatic organisms have a wider range and can tolerate a wide range of pH levels.

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Student Reader/Learning Set Three

Organism 0pH Bacteria can live from Plants/algae Catfish, carp & some insects Bass and bluegill Snails and clams Many fish and insects

2pH

4pH

6pH

8pH

10pH 12pH

14pH

Figure 4. pH scale and the tolerance of various aquatic animals to pH levels.

13. Why do we want to know the pH of the water? _________________________________________________________________________________ _________________________________________________________________________________ 14. Use figure 10 to determine the pH range for bacteria, bass and bluegill, and snails and clams. _________________________________________________________________________________ _________________________________________________________________________________ Turbidity

How clear the water looks can also help you determine the quality of the water. Turbidity is the measure of the relative clarity of water. Suspended materials such as clay, silt, organic and inorganic matter, and microscopic organisms cause turbid water. The murkier the water, the greater the turbidity. Turbid water decreases the number of organisms that can live in the water. This is because there is less sunlight that can penetrate the water. Also, water temperature increases because suspended particles absorb sunlight, causing oxygen levels to fall (remember, warm water holds less oxygen than colder water). Turbid water may be the result of soil erosion, urban runoff, and bottom sediment disturbances. Bottom sediment disturbances can be caused by boat traffic and abundant bottom feeders (organisms that stay near the bottom of the water when feeding). 16. Why is it important to measure the turbidity of the water? _________________________________________________________________________________ _________________________________________________________________________________ 17. What causes turbid water? _________________________________________________________________________________ _________________________________________________________________________________ Student Reader/Learning Set Three

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Fecal Coliform

Fecal coliform is a bacteria that naturally occurs in the human digestive tract and aids in the digestion of food. Fecal coliform bacteria are found in the feces of humans, other warm-blooded animals such as cattle, and birds. However, where there is too much of this type of bacteria present, there is the potential that harmful pathogens can also be present. Pathogens are small organisms or viruses that cause disease. We measure the amount of fecal coliform bacteria found in rivers because the pathogens are scarce and it would take too long to try and find them. Even though they are scarce, it only takes a small amount to make a person sick. In water, if fecal coliform counts are high, there is a greater chance of pathogens being present. Swimming in waters that have high fecal coliform counts can increase a person's risk of getting sick because pathogens enter the body through the skin, cuts, nose, ears, or mouth. Fecal coliform bacteria can enter a river through run-off or sewage discharge. Some cities have a separate sewer system for sewage and run-off, but other cities have a combined sewer system. In a separate sewer system, sewage from toilets, washers, and sinks flow through a sewer and go to the wastewater treatment plant. Rain and snowmelt from streets flows through a separate sewer and discharges directly into a river without any treatment. In a combined sewer system, sewage and storm runoff both go to a wastewater treatment plant. However, during a heavy rain, storm water may be diverted to a combined sewer overflow system (CSO). If this happens, it may go directly into a river, untreated. To prevent this, some cities build retention basins that hold storm water until the treatment plant can handle it. Without a retention basin, heavy rains can result in high fecal coliform counts downstream from sewage discharge.

18. Why do we measure fecal coliform bacteria to determine the health of a river? _________________________________________________________________________________ ________________________________________________________________________________ _________________________________________________________________________________ ________________________________________________________________________________

19. What is a combined sewer overflow system? Why are they important? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ ________________________________________________________________________________

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Student Reader/Learning Set Three

Overall Water Quality Ranking

Fill in the chart below according to the test results of your group. The "Weight" column tells you how important that test is in determining the quality of the water. To get the overall ranking, multiply the Rank column by the Weight column. Record the result in the Overall Ranking column. For example, if your turbidity test result were 65 JTU, then it would have a rank of 2 (fair). You would then multiply 2 x 0.10 and get an overall rank of 0.20. The overall Water Quality Index is the sum of the Overall Rank column. Test

Test results

Rank (A)

Weight (B)

DO % saturation

0.17

BOD

0.16

Temperature

0.11

Phosphate

.011

Nitrate

.011

pH

0.10

Turbidity

0.10

Fecal coliform

0.08

Overall rank (A x B)

Overall Water Quality Index

Overall Water Quality Index Total 4.00 3.00-3.99 2.00-2.99 1.00-1.99 0.99 or less

Water Quality Excellent Good Fair Poor Very poor

20. Write a paragraph describing the overall water quality of the sample that you tested. _________________________________________________________________________________ ________________________________________________________________________________ _________________________________________________________________________________ ________________________________________________________________________________ _________________________________________________________________________________ ________________________________________________________________________________ Student Reader/Learning Set Three

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TESTING PROCEDURES (Cut, separate or laminate as needed.) Testing for DO

Dissolved oxygen needs to be tested at the river to get an accurate reading. The amount of dissolved oxygen in your river will determine what organisms can live there. It will also help you determine the quality of the water in your river. Your teacher will provide the equipment necessary to perform the water quality tests. Materials • Test tube • 2 dissolved oxygen TesTabs • DO color chart 1.

Take the temperature of the water sample.

2.

Submerge the small tube into the water sample. Carefully remove the bottle from the water sample, keeping the tube full to the top.

3.

Drop two Dissolved Oxygen TesTabs® into the bottle. Water will overflow when tablets are added.

4.

Screw the cap on the tube. More water will overflow as the cap tightens. Make sure no air bubbles are present in the sample.

5.

Mix by turning the tube over and over until the tablets have dissolved. This will take about 4 minutes.

6.

Wait 5 more minutes for the color to develop.

7.

Use the DO color chart to compare the color to the sample. Record the result as ppm Dissolved Oxygen.

8.

Locate the temperature of the water sample on the percent saturation chart (fig.3).

9.

Locate the dissolved oxygen result of the water sample at the top of the chart.

10. The percent saturation of the water sample is where the temperature row and the dissolved oxygen column intersect. For example, if the temperature of the water is 18∞C and the DO content is 4ppm, then the percent saturation is 42%. Record this number in the "Test Results" column in the table on the next page. 11. Use Figure 4 to determine the rank for dissolved oxygen percent saturation. Record this number in column A. In the example above, 42% saturation is fair, and gets a ranking of 2.

SR

Student Reader/Learning Set Three

Figure 1:

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dissolved Oxygen % Saturation Chart

*Calculations based on solubility of oxygen in water at sea level, from Standard Methods for the Examination of Water & Wastewater, 18th edition.

Figure 2:

2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Result 91-110 %Sat 71-90 %Sat 51-70 %Sat <50 %Sat

Dissolved Oxygen (ppm) 4 29 31 32 34 35 37 39 41 42 44 46 48 49 51 53

8 58 61 64 68 71 74 78 81 84 88 92 95 99 102 106

Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor)

Student Reader/Learning Set Three

SR

Testing for BOD

Testing for BOD will help you determine the quality of water in the river. This test takes 5 days to perform, so plan ahead. When you take your sample for BOD, remember that the water near the river bottom is where most of the oxygen-demanding organisms are found. So, the best sample is one that is between the surface and the bottom. When you test for BOD, you are trying to determine how much dissolved oxygen in the water sample is used by bacteria. Once you have your sample, you will cover it with aluminum foil and put it in a dark place. This is because you do not want any algae in the water to photosynthesize and produce more oxygen. Putting the sample in a dark place will prevent photosynthesis. In order to complete the BOD test, you will compare the results of this test to the DO test in the previous section. To test for BOD, you will need: • 2 Sampling tubes • Aluminum foil • 4 DO TesTabs • DO color chart 1. Submerge the small tube into the water sample. Carefully remove the tube, keeping it full to the top. Cap the tube. 2.

Wrap the tube with aluminum foil and store it in a dark place at room temperature for 5 days.

3.

Unwrap the tube. Add two Dissolved Oxygen TesTabs® to the test tube.

4.

Cap the tube. Make sure there are no air bubbles. Invert until tablets have dissolved. Wait 5minutes.

5.

Compare the color of the sample to the dissolved oxygen color chart. The difference in the DO level between the uncovered tube (see previous section) and the tube with aluminum foil is the BOD of the water sample. Record the result in the column A. Dissolved Oxygen (with foil) _______________________ Dissolved Oxygen (uncovered)______________________

6.

Look at figure 3 to determine the rank and record it in the "Ranking" column below Result Rank 0 ppm 4 ppm 8 ppm 4 (excellent) 3 (good) 2 (fair) Figure 3:

SR

Result 0 ppm 4 ppm 8 ppm

Rank 4 (excellent) 3 (good) 2 (fair) Student Reader/Learning Set Three

Testing for Temperature

The temperature test measures the change in water temperature at two points. By finding temperature changes along the river, we can determine sources and effects of thermal pollution. Because this test compares the difference between two sites, it is important to match the physical characteristics of the sites (i.e. current stream, depth of the river, etc.) Materials • Low range and high range thermometers • Low Cost monitoring kit container 1.

The two thermometers have an adhesive back. Adhere them to the kit container, 4 inches from the top. The temperature is indicated by a liquid crystal number on the Low Range thermometer and a green display on the High Range thermometer.

Low Range °C High Range °C 14 16 18 20 22 2 4 26 28 30 32 34 36 38 40

blue GREEN tan/red 2.

Wear protective gloves. At each site, fill the cup to the top.

3.

Wait one minute and then read the temperature. Record the temperature as degrees Celsius.

4. 5.

Repeat the test approximately 1 km away as soon as possible and record your results. The difference between the temperature at the two sites is the change in temperature. Record this in column A on page 44.

6.

Use Figure 4 below to determine the rank and record it in column B . Figure 4:

Temperature Change 0-2 ˚C 3-5 ˚C 6-10 ˚C >10 ˚C

Student Reader/Learning Set Three

Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor)

SR

Testing for Phosphate

Materials • Sampling tube • 2 phosphorous (PHOS) TesTabs • phosphate color chart 1.

Fill the sampling tube to the 20 mL line with the water sample..

2.

Add two Phosphorus (PHOS) TesTabs® to the sample.

3.

Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample.

4.

Wait 5 minutes for the blue color to develop.

5.

Compare the color of the sample to the Phosphate color chart.

6.

Record the result in the "Reading" column .

7.

Look at figure 5 below to determine a rank. Enter this number in column A.

Figure 5:

Result 1 ppm 2 ppm 4 ppm

2 0 ml

Rank 4 (excellent) 3 (good) 2 (fair)

Figure 8.

SR

Student Reader/Learning Set Three

Testing for Nitrate

Before you test your water sample, be sure you clean your sampling tube with non-mineral water. Distilled water contains ammonia (NH3) ions that will change the test results. Materials • Sampling tube • 2 wide range CTA testabs • nitrate color chart 1.

Fill the cylinder bottle to the 10 mL line with the water sample.

2.

Add two Nitrate Wide Range CTA TesTabs® to the sample.

3.

Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample.

4.

Wait 5 minutes for the red color to develop.

5.

Compare the color of the sample to the Nitrate color chart.

6.

Record the result as ppm Nitrate in the Reading Column

7.

Use Figure 6 to determine the rank and record it in column A.

Figure 6:

Result 5 ppm 20 ppm 40 ppm

10 ml

Rank 2 (fair) 2 (fair) 1 (poor)

Student Reader/Learning Set Three

SR

Testing for pH

Materials • Sampling tube • Two pH TesTabs • pH color sample chart 1.

Fill the cylinder bottle to the 20 mL line with the water sample. 20 ml

2.

Add two pH TesTabs® to the sample.

3.

Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample.

4.

Compare the color of the sample to the pH color chart.

5.

Record the result in the Reading column. Use Figure 7 to determine the rank. Record the result in column A.

Figure 7:

SR

Result 4 5 6 7 8 9 10

Rank 1 (poor) 1 (poor) 3 (good) 4 (excellent) 3 (good) 1 (poor) 1 (poor)

Student Reader/Learning Set Three

Testing for Turbidity

Turbidity can be tested using a simple device called a Secchi disk. A Secchi disk is a black and white disk that is usually lowered into the water to see how far it goes down before it disappears. However, since you are mostly testing shallow rivers, you will collect a water sample using the kit container. Materials • Water monitoring kit container • Secchi disk icon sticker • Turbidity chart 1.

Remove the backing from the secchi disk icon sticker.

2.

Adhere sticker on the inside bottom of the kit container. Position the sticker slightly off center.

3.

Hold the Turbidity Chart on the top edge of the jar. Looking down into the jar, compare the appearance of the secchi disk icon on the bottom of the kit to the chart. Record the result as Turbidity in JTU with your other recorded data.

pH 4.

Use figure 8 to determine the rank for the result. Record this in the column A.

Figure 8:

Result 0 >0-40 >40-100 >100

coliform turbidity

fill

Color chart

Test kit

Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor)

Student Reader/Learning Set Three

SR

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