GWF-GHB
Structure of Blocks
FOR EACH SIMULATION
BEGIN OPTIONS
[AUXILIARY <auxiliary(naux)>]
[AUXMULTNAME <auxmultname>]
[BOUNDNAMES]
[PRINT_INPUT]
[PRINT_FLOWS]
[SAVE_FLOWS]
[TS6 FILEIN <ts6_filename>]
[OBS6 FILEIN <obs6_filename>]
[MOVER]
END OPTIONS
BEGIN DIMENSIONS
MAXBOUND <maxbound>
END DIMENSIONS
FOR ANY STRESS PERIOD
BEGIN PERIOD <iper>
<cellid(ncelldim)> <bhead> <cond> [<aux(naux)>] [<boundname>]
<cellid(ncelldim)> <bhead> <cond> [<aux(naux)>] [<boundname>]
...
END PERIOD
Explanation of Variables
Block: OPTIONS
auxiliarydefines an array of one or more auxiliary variable names. There is no limit on the number of auxiliary variables that can be provided on this line; however, lists of information provided in subsequent blocks must have a column of data for each auxiliary variable name defined here. The number of auxiliary variables detected on this line determines the value for naux. Comments cannot be provided anywhere on this line as they will be interpreted as auxiliary variable names. Auxiliary variables may not be used by the package, but they will be available for use by other parts of the program. The program will terminate with an error if auxiliary variables are specified on more than one line in the options block.auxmultnamename of auxiliary variable to be used as multiplier of general-head boundary conductance.BOUNDNAMESkeyword to indicate that boundary names may be provided with the list of general-head boundary cells.PRINT_INPUTkeyword to indicate that the list of general-head boundary information will be written to the listing file immediately after it is read.PRINT_FLOWSkeyword to indicate that the list of general-head boundary flow rates will be printed to the listing file for every stress period time step in which “BUDGET PRINT” is specified in Output Control. If there is no Output Control option and “PRINT_FLOWS” is specified, then flow rates are printed for the last time step of each stress period.SAVE_FLOWSkeyword to indicate that general-head boundary flow terms will be written to the file specified with “BUDGET FILEOUT” in Output Control.TS6keyword to specify that record corresponds to a time-series file.FILEINkeyword to specify that an input filename is expected next.ts6_filenamedefines a time-series file defining time series that can be used to assign time-varying values. See the “Time-Variable Input” section for instructions on using the time-series capability.OBS6keyword to specify that record corresponds to an observations file.obs6_filenamename of input file to define observations for the General-Head Boundary package. See the “Observation utility” section for instructions for preparing observation input files. Tables ref{table:gwf-obstypetable} and ref{table:gwt-obstypetable} lists observation type(s) supported by the General-Head Boundary package.MOVERkeyword to indicate that this instance of the General-Head Boundary Package can be used with the Water Mover (MVR) Package. When the MOVER option is specified, additional memory is allocated within the package to store the available, provided, and received water.
Block: DIMENSIONS
maxboundinteger value specifying the maximum number of general-head boundary cells that will be specified for use during any stress period.
Block: PERIOD
iperinteger value specifying the starting stress period number for which the data specified in the PERIOD block apply. IPER must be less than or equal to NPER in the TDIS Package and greater than zero. The IPER value assigned to a stress period block must be greater than the IPER value assigned for the previous PERIOD block. The information specified in the PERIOD block will continue to apply for all subsequent stress periods, unless the program encounters another PERIOD block.cellidis the cell identifier, and depends on the type of grid that is used for the simulation. For a structured grid that uses the DIS input file, CELLID is the layer, row, and column. For a grid that uses the DISV input file, CELLID is the layer and CELL2D number. If the model uses the unstructured discretization (DISU) input file, CELLID is the node number for the cell.bheadis the boundary head. If the Options block includes a TIMESERIESFILE entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.condis the hydraulic conductance of the interface between the aquifer cell and the boundary. If the Options block includes a TIMESERIESFILE entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.auxrepresents the values of the auxiliary variables for each general-head boundary. The values of auxiliary variables must be present for each general-head boundary. The values must be specified in the order of the auxiliary variables specified in the OPTIONS block. If the package supports time series and the Options block includes a TIMESERIESFILE entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.boundnamename of the general-head boundary cell. BOUNDNAME is an ASCII character variable that can contain as many as 40 characters. If BOUNDNAME contains spaces in it, then the entire name must be enclosed within single quotes.
Example Input File
BEGIN OPTIONS
PRINT_INPUT (echo input to listing file)
PRINT_FLOWS (print the flows to the listing file)
TS6 FILEIN tides.ts
BOUNDNAMES
END OPTIONS
# Dimensions block
BEGIN DIMENSIONS
MAXBOUND 15
END DIMENSIONS
# Stress period block(s)
BEGIN PERIOD 1
#Lay Row Col Bhead Cond boundname
2 1 10 tides 15.0 Estuary-L2
2 2 10 tides 15.0 Estuary-L2
2 3 10 tides 15.0 Estuary-L2
2 4 10 tides 15.0 Estuary-L2
2 5 10 tides 15.0 Estuary-L2
2 6 10 tides 15.0 Estuary-L2
2 7 10 tides 15.0 Estuary-L2
2 8 10 tides 15.0 Estuary-L2
2 9 10 tides 15.0 Estuary-L2
2 10 10 tides 15.0 Estuary-L2
2 11 10 tides 15.0 Estuary-L2
2 12 10 tides 15.0 Estuary-L2
2 13 10 tides 15.0 Estuary-L2
2 14 10 tides 15.0 Estuary-L2
2 15 10 tides 15.0 Estuary-L2
END PERIOD
Available Observation Types
| Stress Package | Observation Type | ID1 | ID2 | Description |
|---|---|---|---|---|
| GHB | ghb | cellid or boundname | -- | Flow between the groundwater system and a general-head boundary or group of general-head boundaries. |
| GHB | to-mvr | cellid or boundname | -- | General-head boundary discharge that is available for the MVR package from a general-head boundary or group of general-head boundaries. |
Example Observation Input File
BEGIN OPTIONS
DIGITS 7
PRINT_INPUT
END OPTIONS
BEGIN CONTINUOUS FILEOUT my_model.ghb.obs.csv
# obsname obstype ID
ghb-2-6-10 GHB 2 6 10
ghb-2-7-10 GHB 2 7 10
END CONTINUOUS
BEGIN CONTINUOUS FILEOUT my_model.ghb.flows.csv
# obsname obstype ID
Estuary2 GHB Estuary-L2
END CONTINUOUS