Restoring the River

Section 3 • Lesson 3
Restoring the River
NAAEE Guidelines for Learning:
Vocabulary:
4th Grade
Strands 1 A, E; Strand 2.2 C; Strand 2.3 A; Strand 2.4 A;
Strands 3.1 A, B, C; Strands 3.2 A, B, C; Strand 4 D
Amphipods, anadromous, aquatic, copepods, crustacean,
ecosystem, fishway, gestation, migrates, organism,
phytoplankton, pollution, prey, rain barrel, rain garden,
restoration, spawn, species, terrestrial, viable, zooplankton
5th - 8th Grade
Strands 1 A, E; Strand 2.2 C; Strands 2.4 A; Strands 3.1 A, B,
C; Strands 3.2 B, C; Strands 4 D
Setting:
Lesson Outcomes:
Materials:
Students will understand…
• that the Potomac River is home to a complex web of life that
depends on a healthy river ecosystem supported by healthy
forests
• that when pollution affects one element of a watershed, it
can disrupt the entire ecosystem
• specific restoration practices that can help reduce water
pollution and restore ecosystems
• that they can help restore the Potomac River watershed
Student Pages:
1. “American Shad:” One copy printed on a transparency
2. “Shad Data Sheet:” One copy printed on a transparency
3. “Students Raise, Release Shad:” One printed copy per
student
4. “A Potomac River Food Web:” One printed copy per group
of two to three students
5. “Potomac River Food Web Cards:” One printed copy per
group of two to three students
6. “Westbrook Elementary School Site Map:” One printed copy
per group of two to three students
7. “Restoring the River Worksheet:” One printed copy per
student
8. “Diets of Potomac River Watershed Organisms” (optional):
One printed copy per student
Students will be able to…
• demonstrate their ideas in writing, visually, and/or orally
through a presentation
• create a diagram of a food chain/web
• explain restoration practices that are bringing back
American shad
• investigate a map of existing river problems, and assign
appropriate restoration practices to address each pollution
source
Duration of Activity:
Two to three hours
Summary
Students will investigate the effects of water pollution and dams
on fish and other animals of the Potomac River ecosystem, and
will learn about stream restoration practices. Using a real-life
case study, students will identify strategies to address ecosystem
imbalances, and will compare their solutions with actual work
conducted by other students.
Background Information
Indoors
Teacher Pages:
1. “Restoring the River Worksheet Answer Key”
• Copies of Let the River Run Silver Again! (optional; refer to
Additional Resources for complete details)
• Stickers or colored pieces of paper (optional): at least five of
each color—green, yellow, blue, and red—per group of five
students
Water pollution is one of the greatest threats to the natural
balance of the Potomac River’s ecosystems. Fish and aquatic plants
and insects—which serve as the base of the food chain—are the
first to be impacted by water pollution. Sediment clogs the gills
of fish and aquatic insects. Polluting nutrients cause algal blooms,
which block sunlight from underwater plants, killing them and
reducing hiding places for fish. The decomposing plants and the
algae itself also consume oxygen, reducing levels needed by fish
and aquatic insects for survival. The loss of life at the base of the
food chain can have a domino effect throughout the ecosystem.
The Potomac River watershed is home to complex ecosystems of
interconnected food chains/webs, each dependent on clean water, American shad is one species of fish that plays a critical role in
oxygen, and healthy forests. The disruption of just one component the Potomac River ecosystem, serving as food for many animals,
of any web can disturb all living things, including humans, within including other fish, great blue heron, and bald eagles. Shad are
the ecosystem.
Section 3 • Lesson 3 Restoring the River 3-25
anadromous, living in the ocean but returning to the Potomac
River just below Great Falls to spawn each spring. Bald eagles
have evolved to raise their young at the same time the shad return
to the Potomac to spawn—illustrating the intimate connection
between these two species of the Potomac River’s food web.
During the 1900s, over-fishing, pollution, and the creation of
Little Falls Dam (which blocked shad from returning to their
spawning grounds) caused shad numbers to drop drastically.
Alarmingly low populations of shad spurred Maryland to ban
shad fishing in 1982, and Virginia to do the same in 1993.
To restore the Potomac’s shad population, federal, state, and
regional organizations joined forces. The Interstate Commission
on the Potomac River Basin led a program to install fishways,
enabling shad to reach their spawning grounds. Through this
same program, students raised shad in their classrooms and
released them into the river, and also planted riparian forest
buffers in degraded areas. Since 1996, more than 50 schools
in Maryland, Virginia, and Washington, D.C., have released
hundreds of thousands of American shad into the Potomac, and
the fish are coming back.1
Many of these schools also participate in streamside tree plantings
through Growing Native. Throughout the watershed, federal and
state agencies, as well as nonprofits and community groups, are
active in tree plantings and other restoration activities. Riparian
forest buffers are widely accepted as one of the most costeffective measures for protecting the health of rivers and streams.
According to a 2002 United Nations study, every dollar invested
in watershed protection measures, such as the maintenance of
buffers, can save up to 200 dollars in water treatment costs.2
In concert with our efforts to reduce pollution at its sources,
restoration efforts are important. Working together using a variety
of approaches, we can protect the water quality of the Potomac
River and its tributaries, as well as the lives of the organisms that
depend on these waterways.
Essential Questions
• What types of pollution can harm freshwater fish?
• How can these pollutants be stopped or reduced at their
sources?
• How can the loss of one animal or plant affect other animals
and plants in the same ecosystem?
1
Burk, Sandy. Let the River Run Silver Again! Blacksburg, Virginia: McDonald & Woodward Publishing, 2005. http://www.potomacriver.org/burkbook.pdf.
2
United Nations, 2002. Cited in Berres, Matt, Stephanie Flack, Meredith Lathbury, and
Jennifer Schill. Good Neighbor Handbook: Tips and Tools for River-Friendly Living in
the Middle Potomac Region. Potomac Conservancy and The Nature Conservancy.
2005.
3-26
Growing Native Educational Guide
Pre-assessment
Display the picture of “American Shad” on an overhead projector,
initially concealing the description so that only the shad drawing
is visible. Ask students to write down what they think American
shad eat, and what eats them. Uncover the description and
choose a student to read it aloud to the class. Lead the class in a
discussion of the Essential Questions.
Lesson Procedures
1
On an overhead projector, display the “Shad Data Sheet,”
which details the decline of American shad until the fishery
was closed in 1980. Explain that due to overfishing, pollution,
and dams, the number of shad became very low in the Potomac
River by 1980.
2
Distribute and assign students to individually read the news
article, “Students Raise, Release Shad” and/or the book, Let
the River Run Silver Again! Ask students to take notes on shad
predators and prey, as well as habitat restoration projects that
students conducted in each story to help clean up the Potomac
River. Divide the class into pairs or groups of three and ask them
to discuss and compare their notes.
3
Keeping students in the same groups, distribute the “Potomac
River Food Web Cards” to each group and assign them
to create a food chain/web by linking the cards together in an
appropriate order. Encourage them to refer to the diet descriptions
of each organism listed on the back (folded-over portion) of
the cards, as well as what they learned from the article or book
they read, to guide them. When they have completed their food
chain/web, distribute a copy of “A Potomac River Food Web” to
each group, and ask that it compare its own chain/web to the one
illustrated on this page.
4
Ask each group to remove the shad card from its food chain/
web. Encourage students to discuss within their groups how
the loss of the shad affects other animals in the chain/web.
5
Assign each group to present its food chain/web to the entire
class, and to explain why they chose to put their cards in the
presented order. Ask them to also discuss the overall impact on
the food chain/web as a result of removing the shad.
6
Divide the class into groups of five and distribute “Solution
Stickers” (at least five of each color) and one copy of the
“Westbrook Elementary School Site Map” to each group. Explain
that green stickers represent trees to be planted; yellow stickers,
fishways; blue stickers, rain barrels; and red stickers, rain
gardens. Ask the students to place the “Solution Stickers”
onto the appropriate map locations in which they are needed
to prevent pollution from entering the nearby stream, thereby
protecting aquatic animals (such as the American shad). They
may place more than one Solution Sticker in a given area.
Post-assessment
Distribute one copy of the “Restoring the River Worksheet” to
each student and assign it for homework. Collect the worksheets
and use the resources within this Lesson to assess students’
understanding of the Lesson.
Extensions
7
Ask each group to explain to the class why they placed
their Solution Stickers where they did on the “Westbrook
Elementary School Site Map.” There are no wrong answers, except
if students placed the rain barrel away from the school building.
If anyone misrepresented placement of the rain barrel, explain
why it must be placed adjacent to the school (so that it can be
connected directly to the downspout). For further discussion of
these restoration practices, refer to Let the River Run Silver Again!,
describing where the students in this story implemented each
restoration practice, and why.
• Ask students to create their own food chain/web, referring to
the additional “Diets of Potomac River Watershed Organisms.”
You can take this one step further by leading them in creating
a large mural of the Potomac River that incorporates the food
webs they have identified.
• Encourage students to play interactive games on the Maryland
Department of Natural Resources’ Bay Game web site (www.
dnr.state.md.us/baygame/americanshad.asp) to learn more
about animals in the Chesapeake Bay.
• Lead students in growing aquatic grasses in your classroom
that can be transplanted where they are needed in the Potomac
River watershed. Visit the Maryland Department of Natural
Resources’ Bay Grasses in Classes web site (www.dnr.maryland.
gov/bay/sav/bgic/) for more information.
• Participate in the regional shad restoration project by working
with students to raise shad in your classroom. Learn more on
the Interstate Commission on the Potomac River Basin’s web
site (www.potomacriver.org/living_resources/shad.htm).
Take Action
Encourage students to:
• Become part of a citizen stream monitoring team. They can contact their state Department of the Environment agency to learn
about monitoring opportunities.
• Participate in a streamside tree planting in their community.
• Talk with their family and friends about the importance of clean water to the entire Potomac River food web, and about how they
can reduce pollution.
Additional Resources
• Burk, Sandy. Let the River Run Silver Again! Blacksburg, Virginia: McDonald and Woodward Publishing, 1995.
• “Conserving the Nature of America.” U.S. Fish and Wildlife Service. http://www.fws.gov.
• Lippson, Alice, and Robert Lippson. Field Guide to the Chesapeake Bay. Baltimore, Maryland: Johns Hopkins University Press,
1996.
• “Shad are Being Restocked in the Potomac River.” The Potomac Basin Reporter 54, no. 1 (1998). Interstate Commission on the
Potomac River Basin. www.potomacriver.org/info_center/Reporter_Archive/reporterv541.htm.
• W.A.T.E.R.: Watershed Activities to Encourage Restoration. http://www.watershedactivities.com.
Section 3 • Lesson 3 Restoring the River
3-27