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Healthy Rivers & River Restoration
Learning Target: I can describe some ways that humans have altered rivers and what can be done to restore them to a healthy state. Micah Nelson
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What does a healthy river look like?
Talk to your shoulder partner: What you think a healthy river might look like. What would you see in and around a healthy river? After a minute, draw a picture of what you think a healthy river should look like. Make a T-chart on the board titled “Healthy Rivers.” One side should be titled “What I thought.” The other side should be titled, “What I learned.” When students have completed their drawings, have students share their drawings with small groups or the class and discuss what they included. Add student ideas to the T-chart side labeled “What I thought.”
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Healthy River Definition:
A healthy river is a river that can support a variety of healthy plants, animals and humans. This definition is important for students to be familiar with. Go back to this definition throughout the presentation to remind kids of what constitutes a healthy river.
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Humans have done damage to river health in many ways
Humans have done damage to river health in many ways. Can you describe some of the ways that the rivers below are unhealthy? Examples of damage done by humans (counter-clockwise from top): Pollution from streets/factories makes water unhealthy for humans, animals and plants. Mining gravel and sediment from riverbeds disturbs the ecosystem of the plants and animals that live in the area. Straightening rivers to prevent flooding can cut off floodplain vegetation and animals from the nutrients and water the river provides when it floods Building dams can prevent the travel of fish up and downstream to spawning grounds to lay eggs. It also prevents sediment from being washed downstream for a healthy ecosystem downstream. Wayne McLean
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River Restoration is the effort to return rivers to a healthy state in which they support diverse ecosystems with plants, animals, and humans In the following slides you will learn about problems, solutions, and the benefits of river restoration. Micah Nelson DS: River restoration isn’t really about making rivers more natural, it’s more about making them healthy. We likely can never restore natural conditions, since we can’t define what is natural, and we’ve made so many permanent changes to an already constantly-changing planet that “returning things to their natural state” doesn’t really make sense. We do know a lot about what a healthy river looks like, though, so a better way to think of restoration is like “rewilding” or “restoring healthy ecosystems”.
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Problem #1: Straightening Rivers
Sometimes people change a river channel from a winding path to a straight path. What could be wrong with this? This river has been straightened by humans so that it does not flood the homes next to the river.
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Restoration Solution: Allow Rivers to Migrate
River channels naturally migrate or move across their floodplain over time. Note the patchy, diverse floodplain of this river, which likely supports a variety of plants and animals. When there is a natural flood in a straightened, nothing changes. As a result, habitat doesn’t improve, the soils surrounding the river don’t get supplied with nutrients, and bugs and fish have a very hard time surviving. Most organisms in this river (as few as there are) are likely killed when it floods due to the lack of pools and wood for them to take cover in. South Florida Water Management District
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Restoration Benefits:
When this rivers migrate and flood, they send nutrients onto floodplain forests that create habitat for fish and fertilize the plants. Micah Nelson
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Problem #2: Dam Construction
Dams block the flow of water downstream, preventing the benefits of floods on the floodplain. Dams create reservoirs upstream, permanently covering what used to be a river valley This is another big topic all in itself. One excellent resource is the movie Damnation ( This slides shows Glen Canyon Dam and Lake Powell, behind it
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Restoration Solution: Dam Removal
This dam on the Elwha river in Washington State (left) was removed, and salmon are now migrating back up the river to their original spawning grounds (right).
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Restoration Benefits:
Historic salmon spawning grounds Salmon spawning grounds after dam construction The Elwha river was dammed in the early 1900s, preventing salmon from migrating to their spawning grounds, severely decreasing their population
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Problem #3: Pollutants from Cities and Farming
Water that falls as rain or snow runs off the land and over cities and farms before making its way to a river On the way to the river, water can pick up toxic pollutants, or even normally non- toxic things like nutrients that become toxic at high enough concentrations
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Problem #3: Pollutants from Cities and Farming
Rivers reflect the landscapes around them Restoring rivers means fixing problems all over the landscape One main point to drive home in this slide and the next two is that every action on the landscape has repercussions for river health. As a result, good river restoration must take into account things happening to the land around rivers.
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Restoration Solution: Water Treatment and Changing Land Use Practices
No-till farming helps prevent excess sediment in rivers Retention ponds in urban regions can enable water treatment Stormwater management in cities can be designed to filter and treat water being delivered to streams Corey Coyle
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Restoration Benefits:
Cleaner water being delivered to streams makes for cleaner and healthier streams. Healthy rivers support healthy plants and animals.
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Review Project Get into a team of 2-3 students.
Have students create a poster or series of posters with three slides. One slide should describe a way that humans have negatively affected a river. The second slide should describe or depict an effort to restore the river to a healthier state. The third slide should describe why the restoration is beneficial for the river. Students could do online research to learn about river restoration or they could use information from the slides presented by the teacher. Alternatively, the whole class could do the same example, including the same headings, and then draw their own pictures. Posters could be hung around the school or students could make presentations to other classes.
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Alternative Review Ideas
Contact a river restoration practitioner (or a county or city land manager who works on rivers) and ask them to speak to the class about what they do. Do a skype-a-scientist with a geomorphologist or river restoration practitioner (
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