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Experiment 1: Building a Stream
Channel erosion can be determined by the carrying capacity of the stream for various sediments. In this experiment, you will use a mix of sediment and a steady flow of water to recreate stream development. You will then conduct key streamflow measurements and calculations.
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Materials
Fine Gravel
Funnel
Ruler
Sand
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Soil
Stream Ramp
*Water
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Procedure
1. Assemble the stream ramp by folding the end under the ramp and inserting the tab in the relevant slot, as pictured in Figure 4. For additional support, tape down the elevated end of the ramp.
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Figure 4: Assembled stream ramp.
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Figure 4: Assembled stream ramp.
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2. Measure out 300 mL each of soil, sand and gravel and mix. Place mixture on the upper two-thirds of the surface and smooth evenly.
3. Slowly pour water at surface top through funnel for one minute to simulate a stream. Draw a map to scale of the water channel created using an arrow to indicate flow direction. Describe what effect the water had on the soil. Was there any erosion? Deposition? Did the water flow straight or meander? Record your data in Table 1.
4. Continue adding water for two minutes. Describe changes from the initial one-minute activity. Be sure and note the effects of running water on the sand, soil, or gravel. Which was transported? When you increased the volume of water, did it change the pattern of erosion and deposition? Which particle sizes made the water look muddy? Record your data in Table 2.
5. Measure your stream width and depth in three different locations. Use the velocity given in Table 2 to calculate the water discharge. Include units in your answer.
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Table 1: Observations
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Observations after 1 minute
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Observations after 2 minutes
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Table 2: Observations
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Trial
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Velocity
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Stream Width (cm)
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Average Depth (cm)
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Discharge
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1
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7.2 cm/s
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2
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3
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Please refer to the document download located in the Introduction for your experiment data tables and Post-Lab Questions.
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