GSFLOW

The need to assess the effects of variability in climate, biota, geology, and human activities on water availability and flow requires the development of models that couple two or more components of the hydrologic cycle. An integrated hydrologic model called GSFLOW (Groundwater and Surface-water FLOW) was developed to simulate coupled groundwater and surface-water resources. The new model is based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW). Additional model components were developed, and existing components were modified, to facilitate integration of the models. Methods were developed to route flow among the PRMS Hydrologic Response Units (HRUs) and between the HRUs and the MODFLOW finite-difference cells. This report describes the organization, concepts, design, and mathematical formulation of all GSFLOW model components. An important aspect of the integrated model design is its ability to conserve water mass and to provide comprehensive water budgets for a location of interest. This report includes descriptions of how water budgets are calculated for the integrated model and for individual model components. GSFLOW provides a robust modeling system for simulating flow through the hydrologic cycle, while allowing for future enhancements to incorporate other simulation techniques.

Any questions about GSFLOW should be sent to GSFLOW Help.

Releases

Documentation

GSFLOW document page

Instructions for Preparing Input Files and Running GSFLOW

An approach for preparing input files for GSFLOW is provided in the "Instructions" link below. The approach has been used by the USGS to prepare input files for the Sagehen Creek Watershed model described in the GSFLOW manual (USGS TM 6-D1). The approach is certainly not the only procedure that could be used to prepare input files for the code.

Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. For further information, please see the standard USGS Disclaimer.

U.S. Department of the Interior | U.S. Geological Survey
URL: http://wwwbrr.cr.usgs.gov/projects/SW_MoWS/software/gsflow_s/gsflow.shtml
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Page Last Modified: July 15, 2009