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Surface-Water Routing (SWR) Process for Modeling Surface-Water Flow with the USGS Modular Groundwater Flow Model (MODFLOW)
Overview of the SWR Process
The Surface-Water Routing (SWR) Process was developed to accurately simulate stages, surface-water flows, and surface-water/groundwater interactions in areas where surface-water gradients are small and (or) there is significant management of surface water. A simplified form of the Saint-Venant equations was implemented in the SWR Process based on assumption requirement that it will be applied to continuous simulations (hourly to daily time steps) in support of water-resource planning activities. As a result, the SWR Process was not intended as a replacement for hydrodynamic models that solve the full Saint-Venant equations and are applied to event simulations (sub-hourly time steps).
The SWR Process uses a flexible approach for simulating one- and two-dimensional routing of surface-water flow. The SWR Process is implicitly coupled to the Groundwater Flow Process in MODFLOW. Surface-water routing in SWR can be simulated using a diffusive-wave approximation of the vertically-integrated Saint-Venant equations and/or a simplified level-pool approach. SWR can account for surface-water flow controlled by backwater conditions caused by small water-surface gradients or surface-water control structures. A number of typical surface-water control structures (such as culverts, weirs, and pumps, for example) can be represented, and simple operational rules can be specified to manage surface-water stages and streamflow by moving water from one surface-water feature to another. The non-linear surface-water flow equations implemented in the SWR Process are solved using Newton methods and direct or iterative solvers.
The SWR Process uses the familiar structure of MODFLOW-2005 and the MODFLOW concepts of "packages" and "processes" are retained. This permits versions of MODFLOW-NWT and MODFLOW-2005 that include the SWR Process to work with many of the MODFLOW-related software programs, such as MODPATH, ZONEBUDGET, and parameter estimation programs. MODFLOW-NWT and MODFLOW-2005 with the SWR Process are public domain computer programs. The source code and software are distributed free of charge by the USGS.
SWR Information and Downloads
SWR Process users are encouraged to use the version incorporated into MODFLOW-NWT, even if the features of MODFLOW-NWT are not required for a particular application.
Documentation of SWR
Hughes, J.D., Langevin, C.D., Chartier, K.L., and White, J.T., 2012, Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005): U.S. Geological Survey Techniques and Methods, book 6, chap. A40 (Version 1.0), 113 p. Available online at http://pubs.usgs.gov/tm/6a40/
Note: these versions are no longer actively supported or maintained
Example Applications of the Surface-Water Routing Process
Hughes, J.D., and White, J.T., 2014, Hydrologic conditions in urban Miami-Dade County, Florida, and the effect of groundwater pumpage and increased sea level on canal leakage and regional groundwater flow: U.S. Geological Survey Scientific Investigations Report 2014-5162, 175 p., http://dx.doi.org/10.3133/sir20145162.
Hughes, J.D., Langevin, C.D., and White, J.T., 2014, MODFLOW-based coupled surface-water routing and groundwater flow simulation: Ground Water, http://onlinelibrary.wiley.com/doi/10.1111/gwat.12216/abstract
Point of Contact
Support is provided for correcting bugs and clarification of how the SWR Process is intended to work. Only limited assistance can be provided for applying the SWR Process to specific problems by contacting the point of contact listed below:
U.S. Geological Survey (USGS) Office of Groundwater
Development of the SWR Process was funded in part by the Miami-Dade Water and Sewer Department.
Related USGS Software Resources
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
Please refer to the USGS Water Resources Software User Rights Notice for complete use, copyright, and distribution information. 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.
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