Streams, floods, and sediment transport
This activity is part of the On the Cutting Edge Peer Reviewed Teaching Activities collection.
HideSummary
The students will conduct a fluvial sediment transport study in Little Fountain Creek basin. The overall goal is to compare the size of clasts in the streambed material to the size of clasts that can be transported by various flood events. The objectives are to:
1. characterize the size, shape, and composition of the streambed sediment and interpret changes in the downstream direction
2. assess the size of the sediment that might be transported for a flood with a 2-yr, a 10-yr, and a 100-yr recurrence interval
3. estimate the recurrence interval of the 2013 flood and the size of sediment that event might have transported
4. integrate knowledge gained in a written report with appropriate visual elements.
1. characterize the size, shape, and composition of the streambed sediment and interpret changes in the downstream direction
2. assess the size of the sediment that might be transported for a flood with a 2-yr, a 10-yr, and a 100-yr recurrence interval
3. estimate the recurrence interval of the 2013 flood and the size of sediment that event might have transported
4. integrate knowledge gained in a written report with appropriate visual elements.
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Context
Audience
The field exercise is part of the required 6-credit hour field geology course. The field geology course is certified as a communication intensive course. The two communication modes that are assessed are written and visual. Thus, this exercise emphasizes the student's ability to communicate effectively using written and visual elements.
Skills and concepts that students must have mastered
Students should have completed a sedimentology course or equivalent.
How the activity is situated in the course
The field geology course is a required course at the junior-level. This exercise is taught near the end of the 6 week field geology course.
Goals
Content/concepts goals for this activity
fluvial hydrology, floods, and sediment transport
Higher order thinking skills goals for this activity
analysis and interpretation of data; critical thinking and assessment of assumptions; synthesis of data and concepts into a unified report
Other skills goals for this activity
Communication skills - written and visual
Description and Teaching Materials
Mechanics of the exercise - many students may not be familiar with working in streams, so a discussion of safety is necessary. In this exercise, the stream studied is a low-flow conditions during the late summer when the exercise is conducted. However, stream safety is always covered.
Once the students have practiced, the teams (always three or more students) are released to start their work.
Each person has a walkie talkie.
After an introductory lecture, the students and the teaching assistants, and the professor go to one location along the stream and practice measuring clasts, using levels, and gathering data for the generating cross sections. Walkie talkies.
The needed materials are calipers or measuring tapes or rulers, staff gauges, levels, field notebooks, pencils.
Student handout for 'Streams, floods, and sediment transport" (Acrobat (PDF) 643kB Aug2 19)
Once the students have practiced, the teams (always three or more students) are released to start their work.
Each person has a walkie talkie.
After an introductory lecture, the students and the teaching assistants, and the professor go to one location along the stream and practice measuring clasts, using levels, and gathering data for the generating cross sections. Walkie talkies.
The needed materials are calipers or measuring tapes or rulers, staff gauges, levels, field notebooks, pencils.
Student handout for 'Streams, floods, and sediment transport" (Acrobat (PDF) 643kB Aug2 19)
Teaching Notes and Tips
Safety is a concern. Make sure the stream the students study is at low flow conditions. The exercise can accommodate more student groups by adding additional locations along the study to be studied. Students often need help figuring out which variable to calculate first and how the calculated variables link.
Assessment
Have the students clearly described changes in composition and size in the downstream direction and have the students used an effective graphic to illustrate the changes.
Have the students clearly shown the calculation scheme (method), stated the assumptions, and presented at a flood recurrence graph.
Have the students interpreted the flood recurrence graph correctly and calculated water depths for the various floods of interest and the estimated clast size.
Have the students estimated the size of the clast that was transported in the 2013 flood.
Have the students written a well-composed text that states assumptions, methods, results, and discussion with informative figures.
Have the students clearly shown the calculation scheme (method), stated the assumptions, and presented at a flood recurrence graph.
Have the students interpreted the flood recurrence graph correctly and calculated water depths for the various floods of interest and the estimated clast size.
Have the students estimated the size of the clast that was transported in the 2013 flood.
Have the students written a well-composed text that states assumptions, methods, results, and discussion with informative figures.