River Hydraulics Activity:
Please record the amount of water for each area.
Flood Level (mm)
Infiltration
Runoff
Impervious with
Vegetation in
Channel
Impervious without
Vegetation in
Channel
Pervious with
Vegetation in
Channel
Pervious without
Vegetation in
Channel
Summary Questions:
River Hydraulics:
1. How did vegetation in the channel affect the flood level, infiltration and runoff?
2. How did the perviousness of the channel affect flood level, infiltration and runoff?
3. What conditions would lead to the highest and lowest flood level in the watershed?
Summary Questions:
River Hydraulics:
1. How did vegetation in the channel affect the flood level, infiltration and runoff?
The vegetation slowed down the flow in the river channel and backed up water in the
watershed. This resulted in less runoff and higher flood levels. For the pervious
watersheds, the vegetation led to higher flood levels meaning more water was available
to infiltrate and become groundwater.
2. How did the perviousness of the watershed affect flood level, infiltration and runoff?
The pervious watersheds had increased amounts of infiltration, decreased runoff and
lower flood levels. There was less water in the pervious watershed because some
infiltrates. This results in less water flowing through the channel as runoff and lower food
levels. The impervious watersheds had no infiltration.
3. What conditions would lead to the highest and lowest flood level in the watershed?
An impervious watershed with vegetation in the channel would lead to the highest flood
levels. This is because impervious watersheds result in no infiltration and the vegetation
causes a slower flow into the river channel (water backs up). A pervious watershed
without vegetation in the channel would lead to the lowest flood levels. This is because
water leaves as runoff and flows out the channel at a faster rate.