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MODFLOW-2005: USGS Three-Dimensional Finite-Difference Ground-Water Model

March 4, 2019

Overview of MODFLOW-2005

MODFLOW-2005 hypothetical aquifer system showing layers and grid cells.
A discretized hypothetical aquifer system. (Modified from McDonald and Harbaugh, 1988.)

Note: MODFLOW 6 is presently the core MODFLOW version distributed by the USGS, but MODFLOW-2005 (the previous core version) is still actively maintained and supported.

MODFLOW-2005 (Harbaugh, 2005) simulates steady and nonsteady flow in an irregularly shaped flow system in which aquifer layers can be confined, unconfined, or a combination of confined and unconfined. Flow from external stresses, such as flow to wells, areal recharge, evapotranspiration, flow to drains, and flow through river beds, can be simulated. Hydraulic conductivities or transmissivities for any layer may differ spatially and be anisotropic (restricted to having the principal directions aligned with the grid axes), and the storage coefficient may be heterogeneous. Specified head and specified flux boundaries can be simulated as can a head dependent flux across the model's outer boundary that allows water to be supplied to a boundary block in the modeled area at a rate proportional to the current head difference between a "source" of water outside the modeled area and the boundary block.


Download Current Version of MODFLOW-2005

The current version of MODFLOW-2005 is v.1.12.00, released February 3, 2017.


Documentation for MODFLOW-2005

MODFLOW-2005 is documented in the following reports:

Documentation of MODFLOW-2005 Processes and Packages

The list below provides quick access to the key documentation for MODFLOW processes and packages.  Online Help links point to the most up-to-date input instructions and related details for the process or package in the Online MODFLOW User's Guide.  Original Report links point to the official USGS report describing the theory and input instructions at the time the package or process was first released.  

Additional documentation can be found in the 'doc' subdirectory in the MODFLOW-2005 distribution.


Find MODFLOW-Related Software

Visit the MODFLOW and Related Programs page for a list of MODFLOW-related software.


How to Cite MODFLOW-2005

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 MODFLOW-2005

Harbaugh, A.W., 2005, MODFLOW-2005, the U.S. Geological Survey modular ground-water model -- the Ground-Water Flow Process: U.S. Geological Survey Techniques and Methods 6-A16.

Software/Code Citation for MODFLOW-2005 v1.12.00

Harbaugh, A.W., Langevin, C.D., Hughes, J.D., Niswonger, R.N., and Konikow, L. F., 2017, MODFLOW-2005 version 1.12.00, the U.S. Geological Survey modular groundwater model: U.S. Geological Survey Software Release, 03 February 2017,

Publication Year 2019
Title MODFLOW-2005: USGS Three-Dimensional Finite-Difference Ground-Water Model
Product Type Software Release
Record Source USGS Digital Object Identifier Catalog