| |
Beyond
the Tap
Original
lesson by
BELL LIVE! 1998: Aquatic Adventures, from the Bell Museum of
Natural History, University of Minnesota
Modified and adapted by
Karen Munroe & Rachel Hughes
Edited By Stephanie Nardei, MLS |
|
|
|
| Time: |
4 class
periods |
| Prep Time: |
1 hour |
| Materials: |
Relief and topographical maps of your local area where watersheds
are evident.
Topographic Maps on Wikipedia
Bucket, some large and small rocks, chunks of wood, or boxes,
markers, plastic foam peanuts, several sheets of aluminum foil
or large plastic garbage bags, shallow washbasin, washtub,
or dishpan, 1 sprinkling can or spray bottle per group and
internet access. |
Abstract
Watersheds are complex, multifaceted
systems that serve a variety of needs for humans, plants,
animals, and invertebrates including providing fresh
clean drinking water and habitats. Humans can and do
have numerous effects on watersheds by changing water
flow patterns and introducing pollution. Through discussion
and creation of a model watershed, students will understand
how watersheds function. Students will also explore
their local sources for water by reviewing local watersheds
using a variety of maps and learn about the importance
of watersheds and the impacts humans have on them.
Objectives
Students will:
1. Explain the basic properties of a watershed
including how water flows from higher to lower elevations
and how watersheds are interconnected.
2. Understand how the placement of buildings, roads
and parking lots can be important to watershed runoff.
3. Understand how careless use and disposal of harmful
contaminants can have a serious effect on downstream
watersheds and their inhabitants.
National
Science Education Standards
Content Standard D
Earth and Space Science
In grades 9-12, students review the water cycle as
a carrier of material, and deepen their understanding
of this key cycle to see that it is also an important
agent for energy transfer.
Teacher
Background
EA
watershed is an area of land that catches precipitation
that drains or seeps into a marsh, stream, river,
lake or groundwater. Watersheds are habitats for
living things, such as plants, animals, fish, waterfowl,
aquatic insects, and invertebrates.
The runoff of small watersheds joins together and
their combined areas become a new, larger watershed.
Large watersheds,
such as the Mississippi Basin and the Chesapeake Bay drain
into large bodies of water, and cover immense land areas.
Despite their differences in sizes, all watersheds share
common properties. They all perform the same function of
transporting water over the earth’s surface. The
watersheds encompass suburban lawns, parking lots and city
streets. Water seeps down through the soil to aquifers,
which are underground formations in rocks and soils that
contain enough groundwater to supply wells and springs.
It is clear that humans have a close relationship with
watersheds. We have built reservoirs for water supplies,
hydropower and recreation, straightened and channeled streams
for flood protection, developed towns and cities along
primary waterways, routed water to irrigate dry farmlands,
fertilize agricultural crop fields and also inadvertently
fertilize harmful microorganisms in rivers and lakes through
runoff and improperly disposed of household and industrial
chemicals into watersheds. As a result, watersheds have
experienced a degradation of water quality, reduction of
streamside vegetation and a general degradation of aquatic
and riparian ecosystems.
Watersheds can also have an effect on humans. Floods
are one of the major events in a watershed.
Homes built on
flood plains, low lying areas adjacent to rivers, are
susceptible to flooding conditions when
heavy precipitation exceeds
the watershed’s capacity to absorb water. Rivers,
streams, and lakes overflow, threaten human lives, and
damage or destroy roads, buildings, and flood control
measures. Watersheds can also become dry, causing water
shortages
for those who depend on their lakes and rivers for drinking
water. Water treatment prepares this water for human
consumption, but if the water is laden with chemicals
and microorganisms,
it can be difficult to treat effectively.
Watersheds can be complex, multifaceted systems that
serve a variety of needs for thousands of people. Watersheds
also cross political boundaries; therefore the people
who
manage them must take a broad swath of economic, political,
industrial, ecological, and cultural variables into consideration.
Clean, fresh water is essential to life today, tomorrow,
and 100 years from now. When you learn about the functions
of a watershed and about what watersheds need to be sustainable,
you begin to acquire the necessary intellectual tools
to take care of fresh water.
Related
and Resource Websites
EPA Build Your Own
Watershed
http://www.epa.gov/safewater/kids/activity_grades_9-12_buildyourownwatershed.html
National Geographic on Conservation & Watersheds http://www.nationalgeographic.com/gaw/frwater/frwater_912_teacher.html
City of Tucson 2006 Water Harvesting Guide 
Drainage Basin on Wikipedia http://en.wikipedia.org/wiki/Drainage_basin
|
|
Activity
Days 1- 2
1. Have a large topographic or relief map of your local
area placed in a position so that students are able to
easily see it. If possible, have a map for each group
of four students. Having aerial maps of your area that
show watersheds would also be powerful. Google Earth,
among other online programs, makes these easily available.
As students come in ask them to look over the maps and
aerial photographs and in pairs come up with a definition
of the term ‘watershed’ using examples or
descriptions from their local area. Ask them to write
this down before sharing as a class. Students should
be familiar with the term, but focusing them on watersheds
in relation to their own environment may help to solidify
this concept. Lead a discussion about how people have
used and changed watersheds. Explain that students will
be creating their own watersheds and exploring their
local watershed(s).
2. Divide students into groups of three or four. Set
out all materials students will need to build their watersheds.
Students will create models of watersheds to observe
how they are formed. Assist students as they build and
experiment with their models.
3. In a shallow basin, arrange rocks, wood, or boxes
higher on one end of the basin than the other. Cover
the rocks with aluminum foil or plastic bags. Press and
mold the foil around the rocks to create a miniature
landscape. Make sure the edges of the foil or bags remain
inside the tub—or else you’ll create a waterfall!
Your model will look as though you’ve filled the
basin with lumpy mashed potatoes, and then shoved half
the potatoes to one end to form a lumpy mountain.
4. Use the marker to draw the place where you believe
the main rivers will flow. Then use a spray bottle to
make it “rain” over the land. What happens
to the water? Do streams form? How many? Where do they
form? Count the number of small watersheds that drain
into the main river you drew with the marker. Notice
how all the water flows towards one end of the tub. Remove
the foil from the rocks, remove the rocks from the tub,
and empty the “rainwater” into a bucket.
5. Switch tasks within your group and make another watershed
model. This time, rearrange the rocks in the tub to try
to create a model that illustrates two different watersheds.
Both watersheds should drain into a lake at the lower
end of the container.
6. Your watershed looks like a nice place to live. Why
not build some houses there? Team members should switch
tasks again. Place two foam peanuts (your “houses”)
on flat locations in the watershed. The “rainmaking” student
should rapidly spray water on the upper portion of the
watershed. Observe the houses. Explain that rapidly spraying
a large amount of water creates a flood in the watershed.
Observe the houses during the “rainstorm.” Did
the flood cause different amounts of damage to the houses
(such as causing them to move) based on their location
in the watershed? Were any houses washed away by the
flood? Where would you want to build your own house?
How many watersheds are above the lake that forms at
the bottom of the model? What happens to the size of
the streams, as the watersheds get larger?
Days 3- 4
1. Go to the website: http://cfpub.epa.gov/surf/county.cfm?fips_code=04019.
This website has generalized maps for all 14 watersheds
located in Pima county.
2. Have students locate their local watershed(s) and
any associated watersheds, particularly those downstream.
3. The United States Geological Survey is currently
researching the Upper Santa Cruz watershed (which encompasses
the
city of Tucson; http://minerals.cr.usgs.gov/projects/santacruz/index.htm).
However there is substantial information on the San
Pedro watershed, which is east of Tucson. Use the following
website to help answer the following questions: http://www.srnr.arizona.edu/nemo/index.php?page=characterization
a.
What are the major rivers, streams, creeks and lakes?
Draw and label these on your map.
b. Where does the watershed begin and end? Label
these on your map.
c. What types of geology exist in this watershed?
Describe the geology.
d. What possible sources of contamination and pollution
exist in this watershed (i.e. cities, mine sites)?
Label these on your map.
Extension
1. Arrange a field trip to the community’s water
treatment facilities.
2. While students are making their model watersheds,
you can encourage them to identify first-order
tributaries, second-order tributaries and
have them research stream
shapes and drainage patterns. Ask them
to try to create models that simulate the different
patterns.
3. Have students download clip art of aquatic
flora and fauna at the Environmental
Protection Agency site (http://www.mnsinc.com/eightbal/watershed/outreach/activitypixnonjs.html)
and use it to illustrate the impact watersheds
have on
our environment. The art and icons at this
site would be useful if you have your students
create displays
or make posters for Geography Awareness
Week. Students could
create bookmarks and hand them out during
the week or at a science or geography fair.
4. Have students write a short essay discussing
what they learned about watersheds and
floods. As part
of the essay, have them draw a picture
of a watershed, including a stream and
associated
floodplains. Students
should
also write about the best place to build
homes to avoid
flooding within their watershed. |
Embedded
Assessment
Students
demonstrate their ability to identify and describe watersheds
with a labeled map of a local watershed, which includes
potential sources of pollution and contamination. The
discussion at the beginning of the lesson serves as a
way to assess prior knowledge.
|
|
|
