iMOD Suite

Introduction

The iMOD Suite provides tools to efficiently build and visualize groundwater models.

Deltares is working to integrate and improve our groundwater software. Therefore iMOD is extended with a new iMOD Suite to link to the latest developments on the MODFLOW and on the changing requirements in the field of groundwatermodelling, most pressing currently the support of unstructured grids.

We created the new iMOD Suite to aid pre- and post-processing unstructured groundwater models. Furthermore, a second goal of this suite was to better connect to the latest developments in the data science ecosystem, by utilizing:

  • Existing data format conventions (NetCDF, UGRID) instead of developing new ones, allowing more user flexibility to find the right tools for the right job.

  • Widely used and tested software (QGIS) to which we add our extension, instead of creating complete programs ourselves.

  • Modern programming languages (C++ and Python) that allow connecting to a big and lively software ecoystem.

The iMOD Suite offers different modules which support modelling with MODFLOW 6 (including unstructured meshes):

  1. iMOD Viewer: The iMOD Viewer consist of a standalone 3D viewer and a QGIS plugin. The iMOD QGIS Plugin QGIS plugin allows visualisation of model input and output with tools for cross-sections, timeseries and link to the 3D viewer. It supports structured NetCDF, UGRID and IPF files. And the iMOD 3D Viewer for interactive 3D visualisation of unstructured input and output. Supports UGRID file format and IPF borelog files.

  2. iMOD Python: A Python package to support MODFLOW groundwater modeling. It makes it easy to go from your raw data to a fully defined MODFLOW model, with the aim to make this workflow reproducable.

  3. iMOD Coupler: Software that couples MODFLOW 6 to other computational cores. It currently supports a coupling to MetaSWAP, but additional computational cores are planned in the future.

_images/NHI-zz_cross-section.png

Fig. 1 Easy plotting of 4 dimensional [t, z, y, x] data in the iMOD QGIS plugin. The example shows the chlorine concentrations computed by the NHI fresh-salt model.

_images/NHI-zz_3d_viewer.png

Fig. 2 The chlorine concentrations computed by the NHI-fresh-salt model for the province of Zeeland, plotted in the new iMOD 3D viewer. The top layer is made partly transparent, creating the pretty mist effect in the creek ridges.

Comparison with iMOD 5

The proven technology and expertise of iMOD is consolidated within iMOD 5. iMOD 5 supports structured calculations with MODFLOW2005 and structured MODFLOW 6 and can be coupled to the unsaturated zone model MetaSWAP. The model input and output can be visualised in its fast interactive viewer. The documentation of iMOD 5 can be found here .

Important technological innovations will be developed in the new iMOD Suite, whereas iMOD 5 will be maintained the coming years, but will see no big new feature developments. Table 1 and Table 2 respectively provide comparisons between iMOD Suite and iMOD 5 for the components and supported MODFLOW6 packages.

Table 1 Comparison between iMOD Suite & iMOD 5

iMOD Suite

iMOD 5

computational kernels

MODFLOW 2005, MODFLOW 6, SEAWAT, MT3DMS

MODFLOW 2005, MODFLOW 6, SEAWAT, MT3DMS, MetaSWAP

file types

NetCDF, UGRID, shp, tiff, idf, ipf, gen

idf, ipf, isg, gen

grid types

structured & unstructured

structured & nested structured

scripted pre-processing

iMOD Python

iMOD Batch

interactive pre-processing

(QGIS)

iMOD GUI

scripted 2D plot

iMOD Python

iMOD Batch

interactive 2D plot

iMOD QGIS plugin (& QGIS)

iMOD GUI

scripted 3D plot

iMOD Python

interactive 3D plot

iMOD 3D Viewer

iMOD GUI

Table 2 Supported MODFLOW6 flow packages in iMOD Suite & iMOD 5

Package

Description

iMOD Suite

iMOD 5

DIS

Structured Discretization

x

x

DISV

Discretization by Vertices

x

DISU

Structured Discretization

IC

Initial Conditions

x

x

OC

Output Control

x

x

NPF

Node Property Flow

x

x

HFB

Horizontal Flow Barrier

x

x

STO

Storage

x

x

CSUB

Skeletal Storage, Compaction, and Subsidence

BUY

Buoyancy

CHD

Constant-Head

x

x

WEL

Well

x

x

DRN

Drain

x

x

RIV

River

x

x

GHB

General-Head Boundary

x

x

RCH

Recharge

x

x

EVT

Evapotranspiration

x

x

MAW

Multi-Aquifer Well

SFR

Streamflow Routing

x

LAK

Lake

UZF

Unsaturated Zone Flow

x

MVR

Water Mover