GMS:MF6 GHB Package

The General-Head (GHB) Package dialog

The General-Head (GHB) Package dialog is accessed by double-clicking on the GHB package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

• Sections list – A list of sections that can be turned on or off:
  • Comments – Turn on to make the Comments section visible.
  • Options – Turn on to make the Options section visible.
  • Periods – Turn on to make the Periods section visible. This section is on by default.
• Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
• Options section – Contains the following:
  • Auxiliary Variables... – Click to bring up the Auxiliary Variables dialog.
  • Time Series... – Click to bring up the Time Series Files dialog.
  • Observations... – Click to bring up the Observation Files dialog.
  • Use auxiliary variable as multiplier (AUXMULTNAME) – Name of auxiliary variable to be used as multiplier of general-head boundary conductance.
  • Allow boundary names (BOUNDNAMES) – Turn on to allow boundary names to be included in the list of general-head boundary cells.
  • Print input to listing file (PRINT_INPUT) – Turn on to write the list of general-head boundary information to the listing file immediately after it is read.
  • Print flows to listing file (PRINT_FLOWS) – Turn on to write the list of general-head boundary flow rates to the listing file for every stress period time step in which "BUDGET PRINT" is specified in Output Control.
  • Save flows to budget file (SAVE_FLOWS) – Turn on to write general-head flow terms to the file specified with "BUDGET FILEOUT" in Output Control.
  • Use with Water Mover (MVR) package (MOVER) – Turn on to allows this instance of the General-Head Package to be used with the Water Mover (MVR) Package.
• Periods section – Contains the following:
  • Period drop-down – Use the Increment Up and Down buttons to select the desired period.
  • Define Period – If no period is defined, click to make the spreadsheet editable.
  • Delete Period – Click to delete the existing period.
  • Add Rows – Click to bring up the Add Stresses dialog.
  • Delete Rows – Click to bring up a dialog with three options:
    • Delete from All Periods – Click to delete matching stresses from all periods.
    • Delete from Just This Period – Click to delete matching stresses from just this period.
  • Plot All Periods – Click to bring up the XY Series Editor dialog. Requires that a cell be selected in the table.
  • Open Time Series – Click to bring up the
  • Filter on Selected Cells – Click to turn on filtering on the selected cells.
  • Table – Contains the following:
    • LAY – Used to specify which layer is being applied.
    • ROW – Used to specify which row is being applied.
    • COL – Used to specify which column is being applied.
    • BHEAD – Represents the boundary head.
    • COND – Represents the hydraulic conductance between the aquifer cell and the boundary.

Auxiliary Variables Dialog

The Auxiliary Variables dialog

The Auxiliary Variables dialog is accessed by clicking Auxiliary Variables... in the Options section of many package dialogs. It is used to define an array of one or more auxiliary variable names. It contains the following sections and buttons:

• At the top is an unlabeled section listing all of the variables, one per line. Double-click on a variable name to rename it.
• Insert Row – Click to insert a row above the currently-selected row.
• Add Row – Click to add a row below the currently-selected row.
• Delete Row – Click to delete the selected row.
• Move Up – Move the selected row up.
• Move Down – Move the selected row down.

Note that each variable name must be unique. If two or more variables share a name, variables added since opening the dialog will not be saved.

Time Series Files Dialog

The Time Series Files dialog

The Time Series Files dialog is accessed by clicking Time Series Files... in the Options section of many of the package dialogs. It is used to define an array of one or more time series files. It contains the following sections and buttons:

• At the top is an unlabeled section listing all of the time series files, one per line.
  • Double-click on the first field to see the full file path and name.
  • Click Edit... to open the time series file.
• Insert Row – Click to insert a row above the currently-selected row.
• Add Row – Click to add a row below the currently-selected row.
• Delete Row – Click to delete the selected row.
• Move Up – Move the selected row up.
• Move Down – Move the selected row down.

Observation Files Dialog

The Observation Files dialog

The Observation Files dialog is accessed by clicking Observations... in the Options section of many of the package dialogs. It is used to define an array of one or more observation files. It contains the following sections and buttons:

• At the top is an unlabeled section listing all of the observation files, one per line.
  • Double-click on the first field to see the full file path and name.
  • Click Edit... to open the Observations (OBS) Dialog.
• Insert Row – Click to insert a row above the currently-selected row.
• Add Row – Click to add a row below the currently-selected row.
• Delete Row – Click to delete the selected row.
• Move Up – Move the selected row up.
• Move Down – Move the selected row down.

Add Stresses Dialog

The Add Stresses dialog for the HFB package

The Add Stresses dialog is accessed by clicking Add Rows in the Periods section of several MODFLOW 6 package dialogs. It contains the following sections and options:

• Table – Table Options differ according to each package. See chart below.

• Number of rows to add – Use the Increment Up and Down buttons to select the desired number of rows to add.

• Add to section – Radio buttons with the following options:
  • All defined periods – Select to add the rows to all defined periods.
  • Only this period – Select to add the rows to only this period.

Package	Add Stresses Dialog Table Options
CHD	CHD Options LAY – Used to specify certain layers. ROW – Used to specify certain rows. COL – Used to specify certain columns. HEAD – Represents the head at the boundary.
DRN	DRN Options LAY – Used to specify which layer is being applied. ROW – Used to specify which row is being applied. COL – Used to specify which column is being applied. ELEV – Represents the elevation of the drain. COND – Represents the hydraulic conductance between the aquifer and the drain.
GHB	GHB Options LAY – Used to specify certain layers of the module. ROW – Used to specify which row is being applied. COL – Used to specify which column is being applied. BHEAD – Represents the boundary head. COND – Represents the hydraulic conductance between the aquifer cell and the boundary.
HFB	HFB Options LAY1 – Represents the first of two chosen layers. ROW1 – Represents the first of two chosen rows. COL1 – Represents the first of two chosen columns. LAY2 – Represents the second of two chosen layers. ROW2 – Represents the second of two chosen rows. COL2 – Represents the second of two chosen columns. HYDCHR – The hydraulic characteristic of the horizontal-flow barrier. When this variable is negative it multiplied by the conductance of two cells.
LAK	LAK Options LAKENO_OUTLETNO – A value that defines the reach number associated with the specified PERIOD data. SETTING – Information that is linked to keywords and values. VALUE1 – Value to be entered in relation to the specific project. VALUE2 – Value to be entered in relation to the specific project.
MAW	MAW Options WELLNO – A value that defines the reach number associated with the specified PERIOD data. MAWSETTING – Information that is linked to keywords and values. VALUE1 – Value to be entered in relation to the specific project. VALUE2 – Value to be entered in relation to the specific project. VALUE3 – Value to be entered in relation to the specific project.
RIV	RIV Options LAY – Used to specify which row is being applied. ROW – Used to specify which row is being applied. COL – Used to specify which column is being applied. STAGE – Variable that represents the head in the river. COND – Variable that represents the riverbed hydraulic conductance. RBOT – Variable that represents the elevation of the bottom of the riverbed.
SFR	SFR Options RNO – A value that defines the reach number associated with the specified PERIOD data. SFRSETTING – Information that is linked to keywords and values. VALUE1 – Value to be entered in relation to the specific project. VALUE2 – Value to be entered in relation to the specific project.
UZF	UZF Options IUZNO – An integer value that defines the UZF cell number associated with the specified PERIOD data on the line. FINF – A value that defines the applied infiltration rate of the UZF cell. PET – A value that defines the ET rate of the UZF cell and specified GWF cell. EXDP – A value that defines the ET extinction depth of the UZF cell. EXTWC – A value that defines the amount of water removed from the UZF cell through evapotranspiration. HA – A value that defines the amount of potential air that enters the UZF cell. HROOT – A value that defines the root potential of the UZF cell. ROOTACT – A value that defines how much root activity exists in the UZF cell.
WEL	WEL Options LAY – Represents which layer within the grid to which the chosen well will be assigned. ROW – Represents which row within the grid to which the chosen well will be assigned. COL – Represents which column within the grid to which the chosen well will be assigned. Q – Represents the volumetric well rate at which the recharge (positive value) and discharge (negative value) of the well will be.

Related Topics

• MODFLOW 6