A Collaborative Effort
Title: Stream Profiles and their Relationship to Meanders
Class: Environmental Biology
Grade: 11-12
Timeframe: 1-2 days
Knowledge Gap Topic
Direction of stream flow from smaller tributaries into larger ones,
stream order and streams becoming more meandering as their
gradient decreases.
Subject Matter/
Key Vocabulary
stream flow, elevation, stream profiles, stream gradients, drainage
patterns
Essential Question/
Over-Arching Concept/
Key Understanding
How does topography/elevation/gravity determine the flow/direction
of stream?
Curriculum Connections
 OGT standards
 Local standards
Instructional Objectives
Earth Science 9-10: B, E; 11-12: B, C
Materials
Introduction
 focus event
 varies with teacher
Development
 major parts of unit/
lesson
O1) Students will use Google Earth maps to calculate stream
profiles and meanders of several different rivers to derive the basic
relationship between profile, number of meanders, and approximate
age of river
O2) Students will relate meandering to stream flow, showing that
healthy rivers tend to be steep at the beginning, then gradually
having more and more turns/meanders as it approaches its mouth.
O3) This relationship will be related to urban areas straightening
streams and its effects on riparian zones and stream health.
O4) Students will also be able to realize that small tributaries flow
into larger sections of rivers and that direction of stream flow can be
determined by analyzing the shape of the rivers and its tributaries
1) Computer(s) with Google Earth and knowledge of tools to find
elevation and waypoints
2) Stream Characteristic Worksheet
3) Excel (or other spreadsheet) to do calculations of stream gradients
Set up two different river pictures from Google Earth; one a fairly
young, straight stream with lots of rapids and white water, and
another with many meanders and slower moving. Ask students to
identify the observed differences. Demonstrate how much the river
drops using Google Earth. Then we start the lab.
1) Examine 6-8 streams from around the world on Google Earth for
elevations at various points and distances.
2) Calculate both stream gradients and count numbers of meanders
3) Graph numbers of meanders vs. gradients to discover relationship
Designing Watershed-based Education and Extension Efforts through a Mental Models Research Approach
USDA-CSREES National Integrated Water Quality Program
Rigor/Relevance Quadrant(s)
 link to rigor/relevance
document
Product/Artifacts/Student
Evidence of Understanding
between the two
A: Must use terms correctly … source, headwaters, mouth,
watershed, sedimentation, meander, tributary, gradient, profile.
B: Correctly calculate gradients of various streams
C: Plot gradients vs. meanders to establish relationship
D: Students establish relationships between steepness of streams
and meanders and come up with a general rule regarding age of
streams based on meandering
Students produce spreadsheet and graphs relating gradients of
streams and meanders.
Students generate a general rule regarding age of streams vs.
meandering.
Accommodations
 plan B
 differentiated instruction
You may have to divide teams up so that at least one member is
comfortable with math. Some students just “freaked out” when they
had to calculate a profile … they weren’t hard, but students were
fearful. Those who were better at math seemed to have an easier
time making the connections from the map and meanders to the
math.
Formative
Assessment/Feedback
 measure of progress
Have students check initial gradients calculated to be sure they are
correct.
Check graphs of gradients vs. meanders to be sure students are
graphing correctly
Final Evaluation
 project rubric
 oral or paper quiz/test
 portfolio
Teacher Reflection
 complete after lesson
Designers/Email:
Give students two new streams where they calculate gradients and
meanders. Estimate the age of the stream based on their collected
data and previous data from the lab
My kids really “plugged” away at this lab … because it was using
Google maps, it was engaging, but it was very challenging for most
students. I think an easy profile based on some simple data and a
graph might be needed first before this activity.
(fdonelson@gjps.org)
An activity to provide a practical use of graphing to come up with a general rule.
This lab helps students relate gradients and meanders, thus showing them that as a stream erodes over
time, meanders increase, giving a general way to determine age of streams.
Additional Comments:
This lab is very challenging for the average environmental botany student. Good students find it
challenging, poor students must be given help. However, it is good to stretch them.
Designing Watershed-based Education and Extension Efforts through a Mental Models Research Approach
USDA-CSREES National Integrated Water Quality Program
Stream Characteristics
Name________________________________
Date_________________________________
Part 1: Using Google Earth, find the following rivers. To determine the distance, go to tools > measure
> path. Follow a path along the river are carefully as you can. After noting the distance, clear the path
and make a line directly from the beginning to the end to determine the straight line distance.
1. Mississippi River (30o 26’N, 91o 11’W), from the bridge in Baton Rouge (elevation 10 ft) south
to the island across from a pier at (30o 18’N, 91o 13’W) (elevation 3 ft)
a. River distance _____miles
b. Straight line distance ______ miles
c. Describe the river as one of the following:
i. Fairly straight
ii. Contains some meanders
iii. Has many meanders
2. Delaware River from the Delaware Water Gap (40o 58’N, 75o O8’W), (295 ft) South to the
bridge at Phillipsburg (40o 41’N, 75o 12’W)
a. Distance of river _______
b. Elevation at Phillipsburg bridge________
c. Straight line distance _________
d. Description of river
i. Fairly straight
ii. Some meanders
iii. Many meanders
3. San Juan River near Shiprock- Go from Farmington, (36o 44’N, 108o 15’W ), (elevation 5211
ft.) to Shiprock, NM (36o 46’N, 108o 41’W), (elevation 4892 ft) to
a. Distance of river _______
b. Straight line distance _________
c. Description of river
i. Fairly straight
ii. Some meanders
iii. Many meanders
Part 2:
1. The straightness of a river is called its sinuosity. It can be calculated by dividing the length of
the channel in a section of a river with the straight-line distance of the same section of the river
(as the crow flies). Access the spreadsheet called River Characteristics Exercise from the
Honors Geology Website or course materials. Notice that it contains data from other rivers as
well.
2. Write in your descriptions of the shape of the river in column D.
3. Put the formula (=F3/G3) in row I3 to obtain the sinuosity of the rivers. A meandering stream
would have a sinuosity of 1.5 or greater. Is the Platte River a meandering
Designing Watershed-based Education and Extension Efforts through a Mental Models Research Approach
USDA-CSREES National Integrated Water Quality Program
stream?_______________ Fill in the rest of the column by highlighting cell I3, dragging the
cursor down to the bottom of the column and hitting control d. (fill down command).
4. Did the sinuosity numbers agree with your description of the shape of the rivers?
5. Gradient is change in elevation per mile of distance (literally the rise over run). Calculate the
elevation change for each river by putting the formula =B3-C3 into column E and fill the
formula down as before.
6. Make a graph (x-y scatter graph) of the relationship between sinuosity of a river and its gradient .
Which is the independent variable?
7. Describe in words the result of the graph. Be specific. Is the relationship linear?
8. Print the graph and add a trendline by hand.
Part 3: Testing your hypothesis
1. Now that you have created a graph that predicts the relationship between gradient and sinuosity,
find out if it can predict the sinuosity of another river. Go to Buellton, CA. Find the Santa Ynez
River (34o 36’N, 120o 11’W) and follow it to the ocean. Note the elevation____________, river
distance___________, straight line distance_____________.
2. Calculate the gradient of the Santa Ynez River from Buellton to the ocean ________ ft/mile
3. Using the graph that you created, predict the sinuosity of the Santa Ynez River__________
4. Calculate the sinuosity by measuring the distance and the straight line distance and add them to
your spreadsheet. _______ By hand, plot and label the data point. Was your prediction correct?
Explain why or why not.
5. Go to Mexican Hat, AZ. Go northwest and follow 316 to the end. Start just West of the end of
316 on the San Juan River (elevation 3951 ft) (37o 10’ 23”N, 109o 55’, 53”W) . Follow the river
to the far side of the Mendenhall Loop (37o 10’ 54”N, 109o 53’, 15”W) (elevation 4025).
Determine the gradient and sinuosity and add it to your spreadsheet. Plot the data point. Does
the San Juan River data fit the graph?________ Explain what is unusual about this section of the
San Juan River.
Hand in your data and your graph with this worksheet.
Designing Watershed-based Education and Extension Efforts through a Mental Models Research Approach
USDA-CSREES National Integrated Water Quality Program