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iMOD User Manual version 5.2 (html)


10.11Data Set 10: Number of files

Data Set 10

NFILES,KEY

NFILES

This expresses the number of entries that will follow, zero entries can be defined by NFILES=0. It is possible the reuse the entries obtained in the previous stress period by assigning the value NFILES=-1. For several package a single entry consist of multiple files (parts). Moreover: each individual part of a package should be repeated NFILES times before entering the next part of a package; whenever a single nodata value is read for one of the individual parts of a package for a particular location, the package on that particular location will be turned off!; See table below for the individual parts (No.) of each package (they should be entered in this order!):

Key

No.

Unit

PST

1

-

Number of parameters to be estimated, see Data Set 14, 15, 16 and 17 for more specific input information.

CAP

n

Number of input files. This is the sum of two numbers:
- the 22 compulsory parameter values (or 21 whenever IARMWP=1). See the list below. Parameters can be given as IDF/IPF files or single value.
- the number of additional Metaswap files to be copied to the simulation folder.

1

-

BND

Boundary setting, used to specify active MetaSWAP elements

2

-

LGN

Landuse code

3

cm

RTZ

Rootzone thickness (min. value is 10 centimeter).

4

-

SFU

Soil Physical Unit

5

-

MET

Meteo Station number

6

m+MSL

SEV

Surface Elevation.

7a

-

ART

(if IARMWP=0) Artificial Recharge (= Irrigation) Type, 0=no occurrence, ART\(>\)0 means present at current location whereby ART=1: from groundwater, ART=2: from surface water extraction

7b

-

ART

(if IARMWP=1) Location of the actual Artificial Recharge, the value of each location refers to the attribute ID in the IPF-file (see dataset 8b)

8a

-

ARL

(if IARMWP=0) Artificial Recharge (= Irrigation) Location, number of model layer from which water is extracted.

8b

-

ARL

(if IARMWP=1) IPF with locations (X,Y) for Artificial Recharge (= Irrigation), the number of model layer (ILAY) from which water is extracted, the identification (ID) of the area on which the recharge is applied and the capacity (CAP) in mm/day. All of those as separate columns in the IPF file, thus the following fields: X,Y,ILAY,ID,CAP. Here, the source of the artificial recharge is always groundwater.

9

mm/d

ARC

(if IARMWP=0) Artificial Recharge (= Irrigation) Capacity. The capacity of the irrigation installation. The applied capacity depends on the duration of the irrigation (part of a day) as specified in the file luse_svat.inp

10

m2

WTA

Wetted Area specifies the total area occupied by surface water elements. Value will be truncated by maximum cellsize.

11

m2

UBA

Urban Area, specifies the total area occupied by urban area. Value will be truncated by maximum cellsize.

12

m

PDU

Ponding Depth Urban Area, specifying the acceptable depth of the ponding of water on the surface in the urban area before surface runoff occurs

13

m

PDR

Ponding Depth Rural Area. Same as above but for rural area.

14

day

OFU

Runoff Resistance Urban Area, specifying the resistance surface flow encounters in the urban area. The minimum value is equal to the model time period.

15

day

OFR

Runoff Resistance Rural Area. Same as above but for rural area.

16

day

ONU

Runon Resistance Urban Area, specifying the resistance surface flow encounters to a model cell from an adjacent cell in the urban area. The minimum value is equal to the model time period.

17

day

ONR

Runon Resistance Rural Area. Same as above but for rural area.

18

m/d

QIU

QINFBASIC Urban Area, specifying the infiltration capacity of the soil surface in the urban area. The range is 0-1000 m/d. The NoDataValue -9999 indicates unlimited infiltration is possible.

19

m/d

QIR

QINFBASIC Rural Area. Same as above but for rural area.

20

m+MSL

PWT

Level of the Perched Water Table level. When groundwater falls below this level then the capillary rise becomes zero.

21

-

SMF

Soil Moisture Factor to adjust the soil moisture coefficient. This factor may be used during calibration. Default value is 1.0.

22

-

CFC

Conductivity Factor to adjust the vertical conductivity. This factor may be used during calibration. Default value is 1.0.

n-22

Remaining files will be copied to the simulation folder as set by OUTPUTNAME (Data Set 1).
Examples of these Metaswap files are fact_svat.inp, luse_svat.inp, thsat_svat.inp, mete_grid.inp and para_sim.inp.
For examples of a complete file set/ configuration we refer to existing (regional) models with a Modflow-Metaswap coupling.
For more info about Simgro and Metaswap and references to documentation on the content of the Metaswap files we refer to chapter A.

BND

1

-

IDF with boundary settings; 0 = inactive, \(>\)0 = active, \(<\)0 = fixed for each model layer

SHD

1

m+MSL

IDF with starting heads for each model layer. Inactive cells will be transformed to nodata value -999.99

KDW

1

m\({}^{2}\)/day

Transmissivity for each model layer (trimmed internally to be minimal 0 m\({}^{2}\)/day)

VCW

1

days

Vertical Resistance between model layers (trimmed internally for minimal 0.001 days). For reasons of scaling, it is important to assign the nodata value for VCW to be zero!

KHV

1

m/day

Horizontal Permeability for each model layer.

KVV

1

m/day

Vertical Permeability for each aquitard (in between modellayers!). KVV is assumed to be 1/3*KHV for the modellayers!

STO

1

-

Storage coefficient for each model layer, i.e. the specific storage coefficient multiplied with the thickness of the model layer, for the first unconfined model layer, enter the specific storage coefficient instead, e.g. 0.15.

TOP

1

m+MSL

Top of the aquifer.

BOT

1

m+MSL

Bottom of the aquifer.

KVA

1

-

Vertical anisotropy for aquifers

PWT

6

-

Layer identification of the PWT unit; elements with values \(<\)= 0 will be removed.

-

Storage coefficient of the phreatic part underneath the PWT layer

m+MSL

Top of the PWT layer

m

Thickness of the PWT layer

m

Thickness of layer of the aquifer above the PWT layer in which the transmissivity will be adjusted.

day

Vertical resistance of the clay underlying the PWT unit. This should be larger or equal to the given C value of the PWT layer, otherwise the C value will be used given by the module VCW.

ANI

2

-

The anisotropic factor perpendicular to the main principal axis (axis of highest permeability). Factor between 0.0 (full anisotropic) and 1.0 (full isotropic). Do not use a nodata value of 0.0 since this will deactivate the package!

degrees

The angle along the main principal axis (highest permeability) measured in degrees from north (0), east (90), south (180) and west (270). Do not use a nodata value of 0.0 since this will deactivate the package!

HFB

1

-

GEN file (*.gen) defining the location of faults/horizontal barriers.
When GEN files are assigned to layer number 0, iMOD will assign the fault to the appropriate model layers automatically; in that case the GEN file needs to be a 3D GEN (see section 9.11).
When no TOP and BOT of the aquifer are defined in the runfile, the value FCT*IMP (see Data Set 11) is assigned to a factor \(f\) that is used to multiply the conductances between cells. As a result, when \(f\)=0.0 the barrier is impermeable.
When TOP and BOT are defined in the runfile, the value FCT*IMP refers to the resistance \(r\) between two cells and has 3 options:
\(r\) > 0 : this resistance is added to the geological resistance.
\(r\) < 0 : the resulting resistance between cells is equal to abs(\(r\)). In that way the resistance between cells can become less than the resistance that is based on the permeability of the geological material.
\(r\) = 0 : the resulting resistance between cells is 0. This forces an impermeable barrier.
See section 12.15 for details on how the conductance between cells is calculated.

IBS

4

m+MSL

Preconsolidation head or preconsolidation stress in terms of head in the aquifer. Preconsolidation head is the previous minimum head value in the aquifer. For any model cells in which specified HC is greater than the corresponding value of starting head, value of HC will be set to that of starting head.

-

The dimensionless elastic storage factor for interbeds present in model layer. The storage factor may be estimated as the sum of the products of elastic skeletal specific storage and thickness of all interbeds in a model layer.

-

The dimensionless inelastic storage factor for interbeds present in model layer. The storage factor may be estimated as the sum of the products of inelastic skeletal specific storage and thickness of all interbeds in a model layer.

m

The starting compaction in each layer with interbed storage. Compaction values computed by the package are added to values in this array so that printed or stored values of compaction and land subsidence may include previous components. Values in this array do not affect calculations of storage changes or resulting compaction. For simulations in which output values are to reflect compaction and subsidence since the start of the simulation, enter zero values for all elements of this array.

SFT

2

m+MSL

Stream Flow Thickness

m/d

Permeability

WEL

1

m\({}^{3}\)/day

An IPF file with:

1

Three columns representing the x,y coordinate and the rate, e.g.: x,y,q,{z1,z2}

2

Two columns representing the x,y coordinate and a third column referring to associated files with time-variant rates, e.g. x,y,[id],{z1,z2}
The parameters z1 and z2 express the screen of the well and are optional. Use these parameters in combination with ILAY=0 (see Data Set 11)

DRN

2

m\({}^{2}\)/day

Conductance of the drainage system within a single model cell; elements with values \(<\)= 0 will be removed.

m+MSL

Elevation of the drainage system.

RIV

4

m\({}^{2}\)/day

Conductance of the drainage system within a single model cell; values need to be \(\ge \) 0.

m+MSL

Elevation of the water level.

m+MSL

Elevation of the bottom level. Whenever the elevation of the bottom level is higher than the entered elevation of the water level, iMODFLOW will adjust internally the elevation of the bottom level to be equal to the elevation of the water level. Any corrections made are listed by a negative system number in the *.LST file whenever the IDEBUG flag is set on 1.

-

Infiltration factor:

=0

No infiltration is allowed

\(>\)0

Infiltration is allowed whenever the head is below the stage up to a maximum (stage minus bottom pressure) whenever the head is less than the bottom. Infiltration conductance is calculated as: river conductance * infiltration factor.

EVT

3

mm/day

This option can only be used in combination with ILAY=1
Evapotranspiration strength.

m+MSL

Top elevation for maximal evapotranspi-ration strength.

m

Thickness in which evapotranspiration strength reduced to zero.

GHB

2

m\({}^{2}\)/day

Conductance of the general head system within a single model cell; elements with values \(<\)= 0 will be removed.

m+MSL

Elevation at the general head boundary.

RCH

1

mm/day

This option can only be used in combination with ILAY=1
Recharge strength.

OLF

1

m+MSL

Surface elevation where above overland flow takes place; elements with values equal to the nodata value will be removed.

CHD

1

m+MSL

Elevation of constant heads at the location where BND \(<\) 0 only.

ISG

1

-

Specific segment file for the simulation of water systems directly from vectors.
For more information on the gridding method for both transient and steady-state runs, visit section 12.27

KEY

Text string that identifies the Key of the module/package listed by Data Set 10.