This activity will introduce students to the drastic changes in the
Everglades watershed. They will use their understanding of the historic
changes in the watershed to help them predict what the Everglades
watershed will be like in 2010. This activity will also introduce them
to changes in land use in the Everglades watershed area.
- original and present Everglades watershed maps (see Student Packet),
- graph paper,
- tag board or cardboard for mounting,
- cutouts of historic and present day Everglades watershed, and
students to examine the two watershed maps provided in the Student
Packet. Ask them to compare the maps, then list changes in the
Everglades watershed from the original to the present day. Changes
include the decline in watershed area, the addition of agriculture, the
loss of wetlands, and the introduction of Water Conservation Areas.
- Open a discussion of the changes in the watershed
configuration and how these changes might be results of the impact of
human settlement on the Everglades. Have the students brainstorm
reasons why the watershed configuration has been changed.
Note: Hold this discussion before students read the Student Packet text about the history of the Everglades.
Tell students that their next task will be to determine the
change in area of the Everglades watershed. Have students brainstorm
about ways they can calculate the difference in the areas of the
original and present watershed. Once they have generated a list of
methods for calculating the areas, have students work in pairs or small
groups to determine the change in watershed area. Have each group try a
different technique from the list.
Possible methods for determining the change in the area of the watershed include the following:
- Use string to create shapes within the watershed that students will be able to calculate the area for.
- Put the graph paper on top of the watershed map. Trace the
outlines of the current and historic watersheds. Count the squares
within the traced outlines. Compare the numbers of squares.
- Cut out each of the historic and current day maps. Mount
each of these on cardboard. Weigh the two pieces of cardboard. Compare
- By using two copies of the map, overlay the present
watershed on the original watershed. Find the area of the difference in
the two watersheds, then weigh the difference (as suggested above) or
use graph paper to count the squares within the difference.
- Once the students have completed their measurements, have each
group report their results. (The difference is less than 25 percent)
Have the students suggest why different techniques might yield
different results. Ask students which techniques they believe yield the
In addition to changes in the watershed caused by the extensive
water-management system, other land-use changes have affected the
movement of water in south Florida. Draining and filling in wetlands
for agricultural use and paving for extensive urbanization have
increased runoff and the risk of flood.
the past, wetland areas were like sponges, storing great quantities of
water and serving as a flood control. How does replacing the wetland
with agricultural land or cities increase flood hazards? Students can
model the three, land-use wetlands - foam rubber, sponge, or a premium
paper towel; farmland - mix of sand and potting soil; urban area -
smooth hard surface like a clipboard or coated cardboard (cereal box).
Have students design experiments where they can investigate the
characteristics of surface water on wetlands, farmlands and urban areas
by simulating runoff over models of each surface.