YSI SonTek RiverSurveyor, System Manual

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SonTek/YSI Inc
RiverSurveyor System Manual (May 1, 2007)
125
e. If you will be making a discharge measurement, the distance to the bank is critical to de-
termining the unmeasured side areas (§
5.1
). As such, you must accurately measure the
distance from the ADP to the riverbank (e.g., using a tape measure, range finder, etc).
5. Record data
a. To start recording data, click
Record
(or press
F7
). Data recording begins immediately to
the file name displayed in the
Profile Data
tabular display.
b. The
Start Edge
dialog box (
Figure 7-34
) will be displayed. Select the start bank (left or
right) and enter the distance to the bank. The convention for bank selection is:
Left bank
is on the left side when looking downstream. Click
Advanced
to enter any additional re-
quired values such as bank shape, headwater elevation, and tailwater elevation.
c. Slowly move the vessel from one side of the river to the other. Try to maintain a rela-
tively slow and steady speed and direction. For more information on how to operate and
maneuver the vessel, see §
6.5
–
How to Make Good Measurements from a Moving Vessel
.
d. As the vessel begins to approach the far riverbank, use the
Discharge Data
tabular display
(
View|Show Discharge Display
) to monitor the number of valid cells in the last few pro-
files. Typically, this value (
# Valid Cells
) will decrease as you get closer to the riverbank.
Also, along a steep riverbank, check the signal amplitude in the
Profile Window
to ensure
no beam is reflecting off the riverbank. When you are sufficiently close to the riverbank,
and still have two valid cells, stop the vessel.
e. Accurately measure the distance from the ADP to the riverbank edge.
f. Again click
Record
(or press
Alt+F7
) to stop recording to the data file. You will be
prompted to enter the distance from the ADP to the far riverbank. Enter the value from
step 5.e into the
End Edge
dialog box (
Figure 7-34
).
6. Continue or stop data collection
a. Continue – If you are continuing the process of collecting data (e.g., you are going to
make a comparison run while transecting back to the start point):
(1) Allow the system to keep running in
Play
mode (i.e., data is being received by the
system, but it is not yet being recorded).
(2) Position the vessel at its “new” start point and repeat the data collection/recording
process. That is, repeat steps 4.b through 6. At this point, edge parameters used in the
previous measurement will automatically be set to the new measurement. If values
change, you can change the appropriate parameters after the measurement has begun
(i.e., after clicking
Record
).
Figure 7-34. Start Edge dialog box