National Park Service Mission
...to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.
Black Canyon of the Gunnison National Park and Curecanti National Recreation Area Outreach Education is committed to: Creating an awareness and fostering an appreciation for the mission of the National Park Service and the natural, cultural, and historic resources of Curecanti National Recreation Area and Black Canyon of the Gunnison National Park.
EDUCATION LESSON PLAN
II. ANTICIPATORY SET
III. TEACHING PROCEDURE/METHODOLOGY
Non-renewable resources are in limited supply and cannot be replaced again during our lifetimes. Nonrenewable energy sources come out of the ground as liquids, gases and solids, and they were usually formed millions of years ago. Once we use them all up, they’re gone. A renewable resource is one that can be used to benefit people and can then be replaced for other people to enjoy.
The difference between the two kinds of natural resources has a lot to do with where they're from. For example, your shirt and jeans are probably made from cotton -- which comes from a plant. Farmers harvest the cotton crop every year, but the plants grow back and produce more cotton. Cotton is renewable! Trees are used to build houses, and to heat houses during the winter time in a wood stove or a fireplace. If we cut down one tree and plant the seed for another, trees are a renewable resource.
Let’s look again at our list on the board. Does anyone know the most common way of obtaining electricity in the United States? Coal is used to generate more than half of all electricity produced in the United States. Coal is a non-renewable resource. Since burning coal can have negative impacts on the environment, we also rely on other sources of energy. Renewable energy sources can be replenished naturally in a short period of time. Can anyone name a source of energy that's renewable, and clean? Solar energy, obtained through solar panels, and wind energy, which is harnessed through wind turbines, are two good examples.
Today, we are going to talk about another way in which we get electricity--by using water to create energy. Electricity produced by water is called hydroelectricity (write this word on the board.) ‘Hydro’ means water. What do you think we need to get hydroelectricity from water? Dams! Dams are used to produce hydroelectricity. Has anyone ever been to Curecanti National Recreation Area? Curecanti is located along the Gunnison River. Within Curecanti, there are three big reservoirs, or man-made lakes, that were created when three dams were built, blocking the Gunnison River. Has anyone seen one of the dams at Curecanti? Well sit back and relax, because we’re going to go on a tour of the dams from right here in your classroom!
Slide 1: Welcome to Curecanti National Recreational Area, located along the Gunnison River. If you’ve ever been to Blue Mesa Reservoir, then you’ve been to Curecanti. Curecanti is part of the National Park Service, just like Yellowstone National Park in Montana and Wyoming, or Rocky Mountain National Park, here in Colorado. All national park areas protect something special. Curecanti was created to protect the wildlife and the water, and to provide fun recreational opportunities on the water. Curecanti has three dams within its boundaries. Let’s take a closer look at each of the dams.
Slide 2: Following the Gunnison River downstream, from east to west, Blue Mesa Dam is the first dam we’ll see. It creates the Blue Mesa Reservoir. Further west is the Morrow Point dam, creating the Morrow Point Reservoir, and furthest west is the Crystal dam and Crystal Reservoir.
Slide 3: Let’s start on the eastern end and travel west. First we’ll look at Blue Mesa dam, which is earthen, or made of earth and rock. This is the only one of the three dams in Curecanti that is made of earth and rock.
Slide 4: Morrow point and Crystal dams are thin arch double curvature concrete dams. All three of these dams are used to produce hydroelectricity, and each has a power plant. Crystal dam is smaller than Morrow Point, but other than that, they look fairly similar because they are constructed the same way.
Slide 5: This picture shows the Morrow Point dam being constructed, before it was holding back any water.
Slide 6: The power plant of Morrow Point Dam is located inside a mountain. The power plant is where you will find the turbines and generators, which are used for what? Who remembers? They help produce hydroelectricity. Morrow Point dam produces more hydroelectricity than either of the other two dams.
Slide 7: Well, now that we know what these dams look like, let’s look at their purpose. One of the purposes that we mentioned earlier is to produce hydroelectricity. Let’s take a closer look at how hydroelectricity is produced. Hydroelectric energy is created by the force of water flowing from a higher level, usually a reservoir or lake, through an enclosed pipe called a penstock. The falling water rushes through the penstock and spins the blades of the turbine, creating mechanical energy. The turbine blades are connected to a shaft that turns the generator. The generator has a set of wire coils that pass through a magnetic field changing the mechanical energy into electrical energy. The electricity is then carried over transmission lines to where it is needed, like your house or your school. After having done its job of turning the turbine blades to generate power, the water is released back into the river, where it flows downstream and is used for drinking, swimming, and lots of other uses.
Slides 8-16 are quiz questions.
Slide 17: The dams at Curecanti also provide recreation. Before the dams were built, the Gunnison River was pretty narrow and deep, which made it difficult to travel on. By damming the Gunnison River, the narrow, difficult channel has now become a deep, calm reservoir. How many of you have been to Curecanti? What did you do while you were there? Did anyone go swimming, fishing, or boating? These are some of the ways which we can recreate on reservoirs made by dams.
Slide 18: Dams can also provide water for irrigation. What does irrigation mean? It’s like a giant water sprinkler, to water crops in the fields. Farmers used to be able to irrigate only during certain times of the year when there was enough water in the river. Today, irrigation can happen through many seasons because of all the water in the reservoir.
So it sounds like dams are pretty helpful, don’t you think? They provide electricity, irrigation, and they create big lakes where we can swim and boat. Do you think that dams are all good, or do they have some negative impacts, too? When dams are built, they change the environment, including the habitats of plants and animals.
Slide 19: Some animals like Elk and Big Horn Sheep may have to change their habitat and their behavior patterns.
Slide 20: This bird called the Gunnison Sage Grouse, lives in the sage brush and finds its food there. It lost a lot of its habitat, or the area where it lived and searched for food, when the river was dammed and water drowned the sage brush.
Slide 21: The water is controlled by the dams, so it’s not wild and rough like whitewater rafters prefer.
Slide 22: Tribes of Native Americans lived in this area. Signs of their life, like pieces of pottery or arrowheads, can be found along the river bed. When that area is flooded by a dam, some of them are covered up and hidden, which means that scientists can’t study them to learn more about the native people that lived in this area.
Slide 23: Are humans the only ones that build dams? Who else does? Right, the beaver! Nature’s engineer! Where do beavers like to live?
Slide 24: Right, in and around streams and rivers.
Slide 25: Well, if humans build their dams out of earth, rocks and concrete, what do you suppose a beaver builds a dam with? Trees, (ex. Aspen) and mud. They drag tree limbs to a certain spot and glue them into place with mud, slowing the flow of the stream. They keep cutting down trees, dragging them, and building their dam until the river is no longer flowing, and a reservoir has formed.
Slide 26: The teeth of the beavers grow continuously throughout their lives. Do you know why? Because beavers cut down trees with their teeth! At first beavers will cut down the trees nearest to the stream. They can even cut through a tree that is 6 inches in diameter in just five minutes. Has anybody ever seen a beaver out of the water? If you have, then you know why they cut down the closest trees first. They can move faster in water than on land, which is one reason why they build their dams and reservoirs for protection, and food.
Slide 27: At first, the beaver dam may be leaky, but the beavers constantly dredge up mud, then the flow of the water wedges the mud in the sticks, making the dam effective. Once they have eaten or used all the trees around their reservoir they must expand. Why? (Because beavers aren't very mobile on land.) So, they make a bigger dam, which results in a bigger reservoir, and creates a new habitat for the beaver. What are the positive effects of beaver dams? Good habitat for trout and insects. Reduce erosion down stream. What are some negative effects of beaver ponds? Beaver dams can flood roads. Are there any other negatives?
Slide 28: So, we’ve learned that people aren’t the only ones that build dams, although beavers build them for different reasons. What are some of the reasons that people build dams? To create hydroelectricity, to create reservoirs for recreation, for irrigation, etc. Does everyone agree that building dams is a great idea? Why don’t we build dams on all rivers? Because building dams can have negative consequences, too. It’s important to study a river habitat, and to make sure that only certain rivers, in certain areas, are dammed.
Slides 29-34 are quiz questions.
Slide 35 is background image for the imaginary community for the next activity.
IV. CHECK FOR STUDENT UNDERSTANDING
V. GUIDED PRACTICE
Elk Grove: Riverside Town
“Now, I want you to pretend that there’s a fast-moving narrow river called White River near your town. Because the river moves so fast, every year there’s a big kayaking race that brings a lot of people to your town to eat at your restaurants and stay in the hotels.
The river provides habitat for lots of different animals, including big horn sheep, elk and lots of migrating fish. What do you know about salmon? That’s right. They need to swim back upstream to the place where they hatched in order to lay their own eggs. Otherwise, they can’t reproduce.”
“So life is pretty good, right? You have your homes, your jobs, and your friends nearby. Well, I have some bad news. Last year the White River flooded your town, causing lots of damage and destroying homes. Because of this flood, some people of your town are trying to convince the mayor to build a dam to help control the floods and to create an area where people can boat and swim. The local power plant where some of you work has decided they will use the new dam to create hydroelectricity.”
“The town has decided they would build an earthen dam, so you are going to create a model of the dam to show the mayor, using the rocks, sticks, and Play-Doh we’ve provided you (in groups of 2-4). At the end of this exercise, we will randomly choose one group to test their dam and see whether or not it holds water.”
After each group has been working on their dam for about 5 minutes, ask them to turn their dams in (At this point we can choose the one that looks most solid to test or draw a star on one slip of paper and an exclamation point on the rest. Have one member of each group choose a slip of paper. The group who chooses the star wins the right to test their dam.). Test the dam.
Ask each group to clean up. (This takes about 5-6 minutes)
“The mayor of Elk Grove wants to hear from all of the people in the town before deciding whether or not to actually build the dam. There are many people and animals and plants that would be affected by the dam.” Give each group a laminated form describing who they are (a.k.a. migrating fish, bighorn sheep, power plant workers, kayakers, etc.), and another paper where they can list 2 or 3 reasons why the dam will HELP or HURT them.
Allow each group to select a speaker to read their papers. All other students should pay attention to the multiple points of view, as at the end, they’ll need to vote on whether or not the dam is a good idea.
Take a blind vote (everybody put their heads on their desks, close their eyes, and hold up their hand to vote).
VI. INDEPENDENT PRACTICE
Did You Know?
Morrow Point Dam, found within the silent walls of the Black Canyon, was the first thin-arch, double curvature concrete dam built in the United States (completed in 1968).