USGS Groundwater Information
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GSFLOW: coupled groundwater and surface-water flow model
Overview of GSFLOW
GSFLOW is a coupled Groundwater and Surface-water FLOW model based on the integration of the USGS Precipitation-Runoff Modeling System (PRMS) and the USGS Modular Groundwater Flow Model (MODFLOW and MODFLOW-NWT). GSFLOW was developed to simulate coupled groundwater/surface-water flow in one or more watersheds by simultaneously simulating flow across the land surface, within subsurface saturated and unsaturated materials, and within streams and lakes. Climate data consisting of measured or estimated precipitation, air temperature, and solar radiation, as well as groundwater stresses (such as withdrawals) and boundary conditions are the driving factors for a GSFLOW simulation.
GSFLOW operates on a daily time step. In addition to the MODFLOW variable-length stress period used to specify changes in stress or boundary conditions, GSFLOW uses internal daily stress periods for adding recharge to the water table and calculating flows to streams and lakes.
GSFLOW can be used to evaluate the effects of such factors as land-use change, climate variability, and groundwater withdrawals on surface and subsurface flow for watersheds that range from a few square kilometers to several thousand square kilometers, and for time periods that range from months to several decades.
GSFLOW Information and Downloads
The current release of GSFLOW is version 1.2.1, October 1, 2016. Users are encouraged to read the documents that are provided in the 'doc' directory of this software distribution.
Documentation of GSFLOW
How to Cite
This USGS software has two citations associated with it.
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 GSFLOW
Markstrom, S.L., Niswonger, R.G., Regan, R.S., Prudic, D.E., and Barlow, P.M., 2008, GSFLOW - Coupled Ground-water and Surface-water FLOW model based on the integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Ground-Water Flow Model (MODFLOW-2005): U.S. Geological Survey Techniques and Methods 6-D1, 240 p.
Software/Code Citation for GSFLOW v. 1.2.1
Regan, R.S., Niswonger, R.G., Markstrom, S.L., Maples, S.R., and Barlow, P.M., 2016, GSFLOW version 1.2.1: Coupled Groundwater and Surface-water FLOW model: U.S. Geological Survey Software Release, 01 October 2016, http://dx.doi.org/10.5066/F7WW7FS0
Example USGS Applications of GSFLOW
Albano, C.M., Dettinger, M.D., McCarthy, M.I., Welborn, T.L., and Cox, D.A., 2015, Use of a hypothetical winter-storm disaster scenario to identify vulnerabilities, mitigation options, and science needs in the greater Lake Tahoe, Reno, and Carson City region, USA: Natural Hazards , vol 79, 22 p., DOI 10.1007/s11069-015-2003-4.
Allander, K.K., Niswonger, R.N., and Jeton, A.E., 2014, Simulation of the Lower Walker River Basin hydrologic system, west-central Nevada, Using PRMS and MODFLOW models: U.S. Geological Survey Scientific Investigations Report 2014-5190, 93 p., http://dx.doi.org/10.3133/sir20145190.
Carroll, R. W., Huntington, J. L., Snyder, K. A., Niswonger, R., Morton, C., and Stringham, T. K., 2016, Evaluating mountain meadow groundwater response to Pinyon‐Juniper and temperature in a Great Basin watershed: Ecohydrology, http://dx.doi.org/10.1002/eco.1792
Ely, D.M., and Kahle, S.C., 2012, Simulation of groundwater and surface-water resources and evaluation of water-management alternatives for the Chamokane Creek basin, Stevens County, Washington: U.S. Geological Survey Scientific Investigations Report 2012-5224, 74 p.
Essaid, H.I., and Hill, B.R., 2014, Watershed-scale modeling of streamflow change in incised montane meadows : Water Resources Research, vol. 50, pp. 2657-2678, doi:10.1002/2013WR014420.
Fulton, J.W., Risser, D.W., Regan, R.S., Walker, J.F., Hunt, R.J., Niswonger, R.G., Hoffman, S.A., and Markstrom, S.L., 2015, Water-budgets and recharge-area simulations for the Spring Creek and Nittany Creek Basins and parts of the Spruce Creek Basin, Centre and Huntingdon Counties, Pennsylvania, Water Years 2000-06: U.S. Geological Survey Scientific Investigations Report 2015-5073, 86 p, http://dx.doi.org/10.3133/sir20155073.
Hunt, R.J., Walker, J.F., Selbig, W.R., Westenbroek, S.M., and Regan, R.S., 2013, Simulation of climate-change effects on streamflow, lake water budgets, and stream temperature using GSFLOW and SNTEMP, Trout Lake Watershed, Wisconsin: U.S. Geological Survey Scientific Investigations Report 2013-5159, 118 p.
Hunt, R.J., Westenbroek, S.M., Walker, J.F., Selbig, W.R., Regan, R.S., Leaf, A.T., and Saad, D.A., 2016, Simulation of climate change effects on streamflow, groundwater, and stream temperature using GSFLOW and SNTEMP in the Black Earth Creek Watershed, Wisconsin: U.S. Geological Survey Scientific Investigations Report 2016-5091, 117 p., http://dx.doi.org/10.3133/sir20165091
Huntington, J.L., and Niswonger, R.G., 2012, Role of surface-water and groundwater interactions on projected summertime streamflow in snow dominated regions: An integrated modeling approach : Water Resources Research, vol. 48, W11524, doi: 10.1029/2012WR012319.
Mejia, J.F., Huntington, Justin, Hatchett, Benjamin, Koracin, Darko, and Niswonger, R.G., 2012, Linking global climate models to an integrated hydrologic model: Using an individual station downscaling approach [1.2MB PDF] : Journal of Contemporary Water Research and Education, issue 147, p. 17-27.
Niswonger, R.G., Allander, K.K., and Jeton, A.E., 2014, Collaborative modelling and integrated decision support system analysis of a developed terminal lake basin: Journal of Hydrology, doi: 10.1016/j.jhydrol.2014.05.043. Available online at http://www.sciencedirect.com/science/article/pii/S0022169414004077 or http://authors.elsevier.com/a/1PRMB52cu2~rj
Tanvir Hassan, S.M., Lubczynski, M.W., Niswonger, R G., and Su, Z., 2014, Surface-groundwater interactions in hard rocks in Sardon Catchment of Western Spain: an integrated modeling approach: Journal of Hydrology, doi: 10.1016/j.jhydrol.2014.05.026. Available online at http://www.sciencedirect.com/science/article/pii/S0022169414003904
Woolfenden, L.R., and Nishikawa, Tracy, eds., 2014, Simulation of groundwater and surface-water resources of the Santa Rosa Plain watershed, Sonoma County, California: U.S. Geological Survey Scientific Investigations Report 2014-5052, 258 p., http://dx.doi.org/10.3133/sir20145052.
Huntington, J.L., Niswonger, R.G., Rajagopal, S., Zhang, Y., Gardner, M., Morton, C.G., Reeves, D.M., McGraw, D., and Pohll, G.M., 2013, Integrated hydrologic modeling of Lake Tahoe and Martis Valley mountain block and alluvial systems, Nevada and California [380KB PDF] : Golden, CO, MODFLOW and More 2013 Conference Proceedings, 5 pp.
Markstrom, S. L., Regan, R. S., Niswonger, R. G., Prudic, D. E., and Viger, R. J., 2006, GSFLOW -- A basin-scale model for coupled simulation of ground-water and surface-water flow -- Part A. Concepts for modeling surface-water flow with the US Geological Survey Precipitation-Runoff Modeling System, in Proceedings of the 3rd Federal Interagency Hydrologic Modeling Conference, Reno, NV, April 2-6, 2006: Reston, VA, Subcommittee on Hydrology, Advisory Committee on Water Information, 8 p. Available online at http://acwi.gov/hydrology/mtsconfwkshops/conf_proceedings/3rdFIHMC/7F_Markstrom.pdf
Niswonger, R. G., Prudic, D. E., Markstrom, S. L., Regan, R. S., and Viger, R.J., 2006, GSFLOW -- A basin-scale model for coupled simulation of ground-water and surface-water flow -- Part B. Concepts for modeling saturated and unsaturated subsurface flow with the U.S. Geological Survey modular ground-water flow model, in Proceedings of the 3rd Federal Interagency Hydrologic Modeling Conference, Reno, NV, April 2-6, 2006: Reston, VA, Subcommittee on Hydrology, Advisory Committee on Water Information, 8 p. Available online at http://acwi.gov/hydrology/mtsconfwkshops/conf_proceedings/3rdFIHMC/7F_Niswonger.pdf
Walker, J. F., Hunt, R. J., Markstrom, S. L., Hay, L. E., and Doherty, J., 2008, Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, Northern Wisconsin, in The third Interagency Conference on Research in the Watersheds: Estes Park, CO. Available online at http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.475.9643&rep=rep1&type=pdf
The USGS Modeling of Watershed Systems (MOWS) group has supplemental training and instructional materials available from a 2009 USGS GSFLOW training course:
Richard Niswonger presented a GSFLOW talk at the USGS Menlo Park Water Resources Research Seminar Series in January 2015:
Point of Contact
Support is provided for correcting bugs and clarification of how GSFLOW is intended to work. Only limited assistance can be provided for applying GSFLOW to specific problems by contacting GSFLOW Help or contacting the Office of Groundwater:
U.S. Geological Survey
Related USGS Software Resources
USGS computer programs related to GSFLOW include the following:
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.
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