Observation Data

What is it?

Observed water level measurements that are directly compared to simulated head outputs.

  A. How to Use
  B. Table Option
  C. File Option
  D. IGWServer Option
  E. USGSSensor Option

How to Use

Select the data source for observational data by accessing the drop-down menu next to ‘Obs Data Source’ and select from one of the following options:

- Table – enter observational data directly into the interface
- File – import observational data from a properly formatted .txt file
- IGW Server – import observational data from the IGW server.
- USGSSensor - use live-linked sensor data from monitoring wells (US, Canada)

After adding inputs for all observations, use the ‘Click to Add Data’ button, then click ‘OK’ to use the data points in the calibration chart.

Click on the ‘ReDraw’ button to update the plot of simulation results versus the observation data.

B. Table Option

If the Table option is selected from the drop-down menu, an empty Calibration Data window will appear. The first (header) line in the text table must include the following text:

WellID,Time,X,Y,Zf,Zt,LyrIndex,Obs,Color

One observation per line may be added after the first line.

- the 1st value is the well ID (WellID)
- the 2nd is ‘0’ (to indicate that the comparison is for steady state, or the current time step in the case of transient modeling (Time)
- the 3rd is the x-coordinate of the observation (X), e.g., longitude
- the 4th is the y-coordinate of the observation (Y) , e.g., latitude
- the 5th is the well screen top elevation (Zf), in units of meters
- the 6th is the well screen bottom elevation (Zt), in units of meters
- the 7th is the layer index (LyrIndex), which can be used if the well is to be placed in a specific geological/computational layer in the case that well screen top and bottom elevation information is not available. By default, this value is set to ‘0’ so that the Zf and Zt values are used
- the 8th is the head observation/field measurement (obs), in units of meters
- the 9th is used to specify long-type RGB (Red-Green-Blue) color of the data markers in the calibration plot

C. File Option

Calibration Data window. Select File from the drop-down menu next to ‘Obs Data Source’. When the Calibration Data window appears, click the “Browse…’ button to launch a file browser and navigate to and select the appropriate file for importing.

D. IGWServer Option

Measurements of groundwater levels from some statewide/provincial water well datasets are available on the Server for comparison with simulated head. If the IGW option is selected from the drop-down menu, the Filter for Well Data window will open. This window allows the users to choose which types of wells to from which to import water level observations import.

The figure belows shows the current water level data coverage on our server, with an indication of which statewide/provincial datasets include information to distinguish aquifer type at the well screen location (surifical vs. bedrock).

D. USGSSensor Option

Select this option to utilize water level data from monitoring wells (USGS - USA; Environment Canada - Canada). The sensor data should already be extracted within the calibration area to utilize this option:
Analysis Tools > Data Explorer > USGS Sensor Data