5
•
Using a meter stick, measure the depth of the stream in
meters at each of the equally spaced points along the cross
section. Record the depth and the distance out from one
shore edge, in meters, on a data sheet. Always measure from
the same shore. Be sure to include both the initial distance
and depth and the final distance and depth.
3.
Measuring Flow Velocity
•
Connect the Flow rate sensor to your datalogger.
If you use the computer with an interface position it safely
away from the water.
•
Submerge the impeller of the Flow rate sensor to about
40% of the depth measured at each section. If the section is
shallow enough, use the plastic risers that are included with
the Flow rate sensor to support the sensor on the stream
bed. The risers make it easier to keep the impeller of the
sensor in the same spot and oriented in the same direction.
•
Point the impeller of the sensor upstream (as shown below)
and place it into the flow. Hold the sensor in place for 10 seconds while data are
being collected. Repeat the measurement for each of the remaining sections.
risers
optional
40%
1
2
3
4
5
7
6
Initial
distance
Initial
depth
= 0
= 0
Final
distance
Final
depth = 0
= Stream width
Flow