Ground Truth Studies Teacher Handbook - Aspen Global Change ...

Make a Watershed Model
Objectives
Students will be able to: 1) describe the topography of
the watershed as a three-dimensional model; 2) locate
corresponding features on topographic maps and a threedimensional
model; 3) describe the interactions between
the watershed and human activities.
Method
A three-dimensional watershed model will be created and
used to trace the flow of water across the land and down
a stream or river. Students will create the model from a
two-dimensional topographic map. They will use the
model to trace the path that a water droplet takes across
the watershed and into the watercourse, and will describe
the relationship between the physical features of the
watershed and the location of human activities.
Background
Students are often familiar with only a small portion of
the watersheds within which they live. Building a
watershed model and tracing the flow of water in the
watershed can assist them in understanding the relationship
between the different features of the watershed, and
the interdependence of the human activities in the
watershed. This watershed model can be used as an
important instructional aid for many activities about the
watershed.
Many human activities are influenced by the flow of
water across different land forms in a watershed. People
locate their farms and towns along watercourses to have
a water supply for their homes, their crops and animals,
and their industries. People live near watercourses to
have transportation for the things they need or produce.
People have observed the hazards of flood plains and
employed the relative safety of natural levees for their
building activities. Where rivers impede transportation,
Age
Grades 7 - 12
Subjects
Geology, Geography,
Social Studies, Language Arts, Science
Duration
3-4 hours
Skills
physical modelling
Key Vocabulary
floodplain, levee, watercourse
bridges have been built. Bridges are often placed where
the watercourse is narrow, where the banks on either side
are the same height, and where the water is not too swift.
Trains cannot travel on steep slopes like cars, trucks, and
buses, so railroads are found in flatter areas of the
watershed, while roads may exist in even the steepest
areas. Airports require large flat areas for their runways
and even larger areas without tall obstructions, so they
are often located on the ridge lines or in wide valleys of
the watershed.
Sometimes humans change the shape of a watershed or
the flow of water across it for their own needs. Farm
fields may be terraced, made to look like stairs with
retaining walls, to slow the flow of water downhill. Dams
may be built across watercourses to provide water deep
enough for navigation, to generate electricity, or to create
© ASPEN GLOBAL CHANGE INSTITUTE 1995 GROUND TRUTH STUDIES
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