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Students will demonstrate analytical and critical thinking skills by experimentation with various soils and materials; the goal is to understand why the Red River, set in a flat valley, causes disastrous flooding. |
| Educators Information / The Red River / Flooding |
THE RED RIVER
FLOODING
Grade Level:
4th-8th
Standards Integration:
Minnesota:
Grades 4-5: Scientific
Concepts and Applications: Living
and Nonliving Systems
B1. The
ability to measure and classify objects, organisms, and materials on the basis
of properties and relationships.
Grades 6-8: Scientific
Concepts and Applications: Earth
Systems
2. Designing
and conducting investigations and field studies
Scientific Concepts and Applications: Physical Systems
5. Creating
a model to illustrate a contemporary or historical concept, principle, theory,
or law.
North Dakota:
Grades K-4: Science:
Unifying Concepts
4.1.3 Understand that changes might occur in
properties of materials and position and motion of objects.
Science: Science Inquiry
4.2.1 Know that science is an integrated process of
observing, questioning, hypothesizing, investigating, and reflecting.
Grades 5-8: Science: Unifying Concepts
8.1.2 Understand how models can be used to explain
scientific principles.
Science: Science Inquiry
8.2.4 Use acquired data to develop descriptions,
explanations, predictions, and models.
Materials:
Various soils (potting, clay, etc.), rocks,
sediment, water, tub (bucket or bin)
Objectives:
|
Students will demonstrate analytical and critical thinking skills by experimentation with various soils and materials; the goal is to understand why the Red River, set in a flat valley, causes disastrous flooding. |
Background:
The Red River Valley was formed as a lake plain,
not a river valley. It was cut into
the bed of glacial Lake Agassiz 10,000 years ago. This is why the geography of the Red River Valley is so flat.
As the glacier retreated at the end of the last ice age,
fine-grain sediment was deposited on the lake bottom. This sediment now covers
much of today's Red River Valley. It is relatively impermeable to water, so
runoff or precipitation does not soak in quickly. As a result, water flows into
the rivers and streams, adding to flood level. If there is high moisture content in the soil, this effect is further
magnified. This is compounded by
the flat terrain, which has only shallow slope for runoff from snow and rain. When the Red River spills over its banks,
there are no geographical
features to hold back the water, which quickly spreads out over a very wide
area.
Pre-Visit Activity:
Conduct a scientific inquiry activity to find out
why the Red River Valley is susceptible to flooding. Have the students think about reasons why flooding
occurs often here. Next, allow students to create hypotheses and test these hypotheses with
a variety of materials (soil, rocks, sediment, water, etc.). Have the students
create a chart with the properties of each material. Ask the class to draw conclusions from the chart about why a shallow
river creates a wide flood.
Post-Visit Activity
Explain to the students why the Red River floods by
using a variety of different soils (potting, sand, clay, and plain dirt).
Place each type of soil in a different tub and create a riverbed in the
soil. Make sure the soil around the
riverbed is flat to simulate the land in the Valley. Pour equal amounts of water into each riverbed. The students can see how
water is absorbed in different types of soil as well as how it spreads out on a
flat surface. They should conclude
that when there is too much water for soil the soil to absorb, and the land does
not have physical features that deflect water, flooding occurs.