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Water Software > Groundwater Software > MODFLOW and Related Programs > FloPy

FloPy: Python package for creating, running, and post-processing MODFLOW-based models

Overview of FloPy

FloPy is a Python package for creating, running, and post-processing MODFLOW-based models. FloPy includes support for MODFLOW-2000, MODFLOW-2005, MODFLOW-NWT, MODFLOW-USG, and MODFLOW-LGR. Other supported MODFLOW-based models include MODPATH (version 6), MT3D, MT3D-USGS, and SEAWAT.

The most recent provisional (development) version of FloPy and supporting information can be found on the GitHub website, where users can also submit code issues or questions.

FloPy Information and Downloads

FloPy Downloads

FloPy Installation

FloPy can be installed using the Python pip utility. To install the FloPy version distributed from this website, open a command line terminal and enter

pip install

If FloPy is already installed on your computer, then type the following command from a terminal window to upgrade to the current version:

pip install --upgrade

FloPy requires Python 2.7 or Python 3.3 (or higher). The FloPy software is dependent on a number Python packages. The list of these dependencies can be found on the FloPy GitHub site.

Documentation of FloPy

How to Cite

This USGS software has two citations associated with it.

  1. The report citation is for the original report or article documenting the underlying theory, methods, instructions, and (or) applications at the time the initial version of the software was released. This digital object identifier (DOI) is for the report.
  2. The software release citation is for the software/code itself (now referred to by USGS as a "Software Release") and references a specific version of the code and associated release date. This DOI links to the code.

In instances where an author is citing use of this software, it would be appropriate to cite both the report documenting the code and the specific software release version that was used.

Report Citation for FloPy

Bakker, M., Post, V., Langevin, C. D., Hughes, J. D., White, J. T., Starn, J. J. and Fienen, M. N., 2016, Scripting MODFLOW model development using Python and FloPy: Groundwater, doi:10.1111/gwat.12413

Software/Code Citation for FloPy v3.2.9

Bakker, M., Post, V., Langevin, C.D., Hughes, J.D., White, J.T., Starn, J.J., and Fienen, M.N., 2018, FloPy v3.2.9: U.S. Geological Survey Software Release, 19 February 2018,

Point of Contact

Support is provided for correcting bugs and clarification of how FloPy is intended to work. Only limited assistance can be provided for applying FloPy to specific problems.

If you think you have discovered a bug in FloPy, or if you have a suggestion for improvement, you can submit an issue here through the FloPy GitHub site.

Additional inquires can be submitted by emailing USGS or contacting one of the developers below.

Joseph Hughes
Earth Systems Modeling Branch
Integrated Modeling and Prediction Division
Water Mission Area, U.S. Geological Survey
411 National Center
12201 Sunrise Valley Drive
Reston, VA 20192

Christian Langevin
Earth Systems Modeling Branch
Integrated Modeling and Prediction Division
Water Mission Area, U.S. Geological Survey
411 National Center
12201 Sunrise Valley Drive
Reston, VA 20192

Other USGS Groundwater Software

The USGS develops groundwater, water-quality, surface-water, and other water-resources software for use by the USGS in fulfilling its mission. Most of this software is available online for download at no charge.

Disclaimers and Notices

This software has been approved for release by the U.S. Geological Survey (USGS). Although the software has been subjected to rigorous review, the USGS reserves the right to update the software as needed pursuant to further analysis and review. No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. Furthermore, the software is released on condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use. Also refer to the USGS Water Resources Software User Rights Notice for complete use, copyright, and distribution information.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

See also, USGS policy on linking to non-Federal web sites.

Software License and Purchase Information

This software is a product of the U.S. Geological Survey, which is part of the U.S. Government.


This software is freely distributed. There is no fee to download and (or) use this software.


Users do not need a license or permission from the USGS to use this software. Users can download and install as many copies of the software as they need.

Public Domain:

As a work of the United States Government, this USGS product is in the public domain within the United States. You can copy, modify, distribute, and perform the work, even for commercial purposes, all without asking permission. Additionally, USGS waives copyright and related rights in the work worldwide through CC0 1.0 Universal Public Domain Dedication ( [Link exits USGS]).

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Page Last Modified: Thursday, 22-Feb-2018 10:23:40 EST