Introduction

FloPy includes support for MODFLOW 6, MODFLOW-2005, MODFLOW-NWT, MODFLOW-USG, and MODFLOW-2000. Other supported MODFLOW-based models include MODPATH (version 6 and 7), MT3DMS, MT3D-USGS, and SEAWAT.

For general modeling issues, please consult a modeling forum, such as the MODFLOW Users Group. Other MODFLOW resources are listed in the MODFLOW Resources section.

Documentation

Documentation is available on Read the Docs and includes information on FloPy; tutorials for using FloPy with MODFLOW 6 and previous versions of MODFLOW, MT3DMS, MT3D-USGS, MODPATH, and ZONEBUDGET; and code documentation.

Contributing

Bug reports, code contributions, or improvements to the documentation are welcome from the community. Prior to contributing, please read up on our guidelines for contributing and then check out one of our issues in the hotlist: community-help.

How to Cite

Citation for FloPy:

Bakker, Mark, Post, Vincent, 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, v. 54, p. 733–739, doi:10.1111/gwat.12413.

Software/Code citation for FloPy:

Bakker, Mark, Post, Vincent, Hughes, J. D., Langevin, C. D., White, J. T., Leaf, A. T., Paulinski, S. R., Bellino, J. C., Morway, E. D., Toews, M. W., Larsen, J. D., Fienen, M. N., Starn, J. J., Brakenhoff, D. A., and Bonelli, W. P., 2025, FloPy v3.9.5: U.S. Geological Survey Software Release, 01 October 2025, https://doi.org/10.5066/F7BK19FH License

Unless otherwise noted, This project is in the public domain in the United States because it contains materials that originally came from the United States Geological Survey, an agency of the United States Department of Interior. For more information, see the official USGS copyright policy at https://www2.usgs.gov/visual-id/credit_usgs.html#copyright

Additionally, we waive copyright and related rights in the work worldwide through the CC0 1.0 Universal public domain dedication.

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