Hi, my name is Nick Stasulis and I am hydrologic technician with the Maine office of the New
England Water Science Center.
In this screencast, I will discuss the basic field review procedures for a midsection measurement
collected in RiverSurveyor Stationary Live.
-Let’s start with the System Tab -In the System Settings, look over the tagline
azimuth, which is only entered if the compass was used for angle correction, and check the
salinity, as well.
The azimuth should be the heading of the cross-section in the direction of the right river bank.
-Confirm the track reference is set to system (the default) and the depth reference is set
to bottom track or vertical beam, as appropriate -The discharge method should be set to mid-section.
-In the field notes, confirm the water temperature and ADCP readings were within 2 deg C before
the measurement began.
If there were discrepancies, a user input water temperature could be entered here, but
this should not be routine.
This temperature will override the ADCP temperature.
-Most of the other information in the system tab is supplementary and does not affect discharge
computations.
-Next, we’ll review the Transect Tab -This tab is likely the most efficient place
to determine major data quality issues.
-Start by scanning the contour plot for any irregularities in depth, velocity, ice information
and other information displayed.
Also ensure there is a black space at the top of each station, indicating a screening
distance was entered.
Ideally, no station would have more than 5% of the total flow.
-Scan the angles indicated using XYZ (where the unit is aligned manually) or ENU (where
the compass is used to correct for angles).
Inconsistent angles could be attributed to user error in how the unit was held when using
XYZ or due to an incorrect tagline azimuth or compass errors when using ENU.
Ultimately, you should ensure indicated angles are reasonable based on observed flow conditions
and make hydraulic sense.
-Starting on either edge, scan through the stations using the left/right arrow keys and
look over the SNR and velocity profile plots.
In the SNR plots, look for large inconsistencies, including separation between beams and spikes
in one or more beams.
In the velocity plot, look for reasonable agreement of the measured data with the extrapolated
data, and for a general reasonable profile shape vertically.
A separate screencast will cover evaluating extrapolation in more detail.
-Double clicking on any station will bring up a dialog with settings for that station.
This is where you could edit the station location, water surface type, ice information, transducer
depth, screening distance, coordinate system or profile extrapolation method.
-The Time Series Tab will allow you to quickly review parameters from each station plotted
together in one view.
-These parameters could include vertical beam and bottom depths, water temperature, pitch
and roll, battery voltage, profiling modes and many other settings.
Again, look for consistency, values that are reasonable based on the channel conditions
and a hydraulic knowledge of the station.
-When using the time series tab, be sure the plots are scaled appropriately and be sure
to change the data being viewed by right clicking, as needed.
A few examples of useful things to check here are vertical beam depth versus bottom track
depth, instrument alignment and magnetic error.
-The Samples Tab is another quick way to check each station for consistent processing settings
and data collection results.
-This table includes station information like the coordinate system used for each.
You should also review other tabular data like flow angle, number of cells, station
discharge, mean velocity and depth.
This table is customizable by right clicking on the header.
Note the percent discharge is not computed unless a rated discharge is entered in the
system tab.
-The Discharge Measurement Summary, accessed by clicking this icon in the toolbar, is another
quick way of viewing lots of important measurement details.
- Scan the system setup and discharge calculation settings and the uncertainty values provided.
Look over the station details and ensure the water surface type, temperatures, depths,
flow angles, and other fields are consistent if you haven’t reviewed them already.
After conducting this preliminary review, address any issues you might find, as needed.
Some issues may be resolved by simply changing software settings or entries (such as an incorrectly
entered station location), but some issues may require data to be re-collected.
Once the measurement has been satisfactorily reviewed, save the discharge summary file
to import into SVMobile.
In the next screencast, we will show some examples of issues commonly identified in
the RiverSuveyor Stationary Live software.