--- title: FloPy Installation Tutorial description: "**FloPy** is a Python package that allows you to create, run, and post-process MODFLOW models. Essentially, this is an interface for working with MODFLOW, albeit not in a graphical format like typical software such as GroundwaterVistas or ModelMuse, but rather…" url: "https://hydrosymple.com/resources/flopy-installation-tutorial/" updated: "2025-02-03" category: Software installations / FloPy --- # FloPy Installation Tutorial **FloPy** is a Python package that allows you to create, run, and post-process MODFLOW models. Essentially, this is an interface for working with MODFLOW, albeit not in a graphical format like typical software such as GroundwaterVistas or ModelMuse, but rather through program code. Below, you will find instructions on installing FloPy and getting started with it. ### Installation of Python - Install the current version of **Python** from the official [website](https://www.python.org/downloads/). ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine1.png) - During the Python installation process, check the *Add Python to path* option, leaving the other parameters at their default settings, then click on *Install Now*. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine2.png) ### Download and storage of MODFLOW executable files - Download the **MODFLOW packages .exe files** you may need; hereafter there are some of the most used packages, their executable file names, and their link for the download. | **Exe file name** | **Package** | **Download link** | | --- | --- | --- | | mf2005.exe | MODFLOW 2005 | [https://water.usgs.gov/water-resources/software/MODFLOW-2005/](https://water.usgs.gov/water-resources/software/MODFLOW-2005/) | | mf6.exe | MODFLOW 6 | [https://water.usgs.gov/water-resources/software/MODFLOW-6/](https://water.usgs.gov/water-resources/software/MODFLOW-6/) | | mfusg.exe | MODFLOW-USG | [https://water.usgs.gov/water-resources/software/MODFLOW-USG/](https://water.usgs.gov/water-resources/software/MODFLOW-USG/) | | mpath7.exe | MODPATH 7 | [https://water.usgs.gov/water-resources/software/MODPATH/](https://water.usgs.gov/water-resources/software/MODPATH/) | | mt3dms5b.exe | MT3DMS | [https://github.com/MODFLOW-USGS/mt3dms?tab=readme-ov-file](https://github.com/MODFLOW-USGS/mt3dms?tab=readme-ov-file) | | mt3d-usgs_1.1.0_64.exe | MT3D-USGS | [https://water.usgs.gov/water-resources/software/MT3D-USGS/](https://water.usgs.gov/water-resources/software/MT3D-USGS/) | | swt_v4.exe | SEAWAT | [https://water.usgs.gov/water-resources/software/SEAWAT/](https://water.usgs.gov/water-resources/software/SEAWAT/) | | pest.exe, plproc.exe, various others | PEST, PLPROC, Groundwater Utilities | [http:\\\\www.pesthomepage.org\\Downloads.php](http://www.pesthomepage.org/Downloads.php) | - For MODFLOW and PEST .exe files, it is recommended to create a folder in the C: directory of your PC, in order to create a short path as C:\\EXE. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine3.png) - In some countries (such as Italy), there is a quite banal (but common!) reason why our first modelling approaches “do not work” (regardless of using FloPy or modeling GUIs), and usually this reason is not written anywhere. **MODFLOW & Co. need to read real numbers with decimals separated by points**. The most common operations to address this are as follows: • Go to *Control panel > Clock and Region > Region > Additional settings…* • Select the point as decimal symbol and comma as digit grouping symbol. • Apply and close   - Other tips/rules to follow are: • **Do not use long paths for the model working directory**, i.e., don’t store them on your desktop. • Use only the Latin alphabet. • Each model must be stored in its own folder. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine1-1.png) ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine2-1.png) ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine3-1.png) - For FloPy to access MODFLOW executables files, it must be set their path in the *system environment variables*. Go on *Control Panel* | *System and Security* | *System* | *Advanced system settings* | *Advanced* and then click on *Environmental Variables* or in the Start menu just enter “Edit system environment variables”. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine5.png) ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine6-1.png) - In the window that opens, in the *System variables* block, select the **Path** variable and click *Edit*. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine7.png) - Create a new path by clicking on *New…*, type the path to your executable files repository, and then click *OK*. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine8.png) ### Installation and Test Run of FloPy - Click on *Start* and enter **cmd** in the search field, then launch the command line. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine9.png) - Inside the command line, enter **pip install flopy**: the download should start (internet connection is required!). ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine10.png) ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine11.png) - Create an environment for working with FloPy. A suitable solution could be **Jupyter Notebook**: it allows to visualize simulation results on the fly and share code with colleagues.   - Install Jupyter Notebook via the command line: enter **pip install jupyterlab** and wait for the installation to complete. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine12.png) - Now enter **pip install jupyter** notebook in the command line. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine13.png) - Create a folder, i.e. JupiterBook, on your pc (in C: as usual is good) in which the code files will be stored.   - In the new folder, open the command line by replacing the path in the address field with **cmd** and press Enter. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine14.png) - In the command line, enter **jupyter notebook** and then Enter. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine15.png) - The default browser will open. Click on **New** at the top right and select **Python3 (ipykernel)**. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine16.png) ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine17.png) - In the input field, copy the code of [this test model](https://flopy.readthedocs.io/en/3.3.5/_notebooks/tutorial01_mf.html#Running-the-Model), as shown in the picture below. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine18.png) - Click on the Run button. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine19.png) - If everything is done correctly, you should see a new cell with the following text file displayed. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine20.png) - If you want to look at the results of the model run, enter the code provided in the webpage as it follows. Then click on the run button: you should see the contour plots of the model's heads. ![](https://hydrosymple.com/wp-content/uploads/2024/03/Immagine21.png)