Modeling Surface and Subsurface Flow on High Performance Computers

ParFlow is an open-source, object-oriented, parallel watershed flow model. It includes fully-integrated overland flow, the ability to simulate complex topography, geology and heterogeneity and coupled land-surface processes including the land-energy budget, biogeochemistry and snow (via CLM). It is multi-platform and runs with a common I/O structure from laptop to supercomputer. ParFlow is the result of a long, multi-institutional development history and is now a collaborative effort between CSM, LLNL, UniBonn and UCB. ParFlow has been coupled to the mesoscale, meteorological code ARPS and the NCAR code WRF.


IGWMC Simulation of the Little Washita Watershed in Oklahoma using the fully-coupled, fully-parallel ParFlow.CLM code. This image is a snapshot of soil moisture with dark blue representing fully-saturated conditions and reddish colors representing dry conditions. Note that groundwater converges and discharges in the valley, forming the Little Washita River. From Chow et al. (2006).
IGWMC Tracer transport results from a 25million node variably saturated ParFlow simulation of infiltration through a 200m thick vadose zone resulting from a long-term infiltration study. The tracer transport is simulated using the particle tracking code SLIM-FAST. From Maxwell et al. (2006).
IGWMC Example of a saturated hydraulic conductivity distribution using a correlated, Gaussian random field and the associated relative saturation profile after 45 min simulation time (bottom) using ParFlow with the overland flow boundary condition. From Kollet and Maxwell (2006).
IGWMC Contamination, Risk and Heterogeneity
IGWMC Analysis of Subsurface Contaminant Migration and Remediation Using High Performance Computing

The PARFLOW manual, codes, and examples can be downloaded from here.

To report bugs, request features, or ask general usage questions, send email to Please note that ParFlow is an unsupported research code and while we will attempt to answer questions posted to this list, there is no guarantee that there will be any reply.

For more information, please contact Reed M. Maxwell .