Feedback of land subsidence on the movement and conjunctive use of water resources

The dependency of surfaceor groundwater flows and aquifer hydraulic properties on dewateringinduced layer deformation is not available in the USGS's groundwater model MODFLOW. A new integrated hydrologic model, MODFLOW-OWHM, formulates this dependency by coupling mesh deformation with aquifer transmissivity and storage and by linking land subsidence/uplift with deformationdependent flows that also depend on aquifer head and other flow terms. In a test example, flows most affected were stream seepage and evapotranspiration from groundwater (ETgw). Deformation feedback also had an indirect effect on conjunctive surfaceand groundwater use components: Changed stream seepage and streamflows influenced surface-water deliveries and returnflows. Changed ETgw affected irrigation demand, which jointly with altered surface-water supplies resulted in changed supplemental groundwater requirements and pumping and changed return runoff. This modeling feature will improve the impact assessment of dewatering-induced land subsidence/uplift (following irrigation pumping or coal-seam gas extraction) on surface receptors, inter-basin transfers, and surfaceinfrastructure integrity. © 2014 Published by Elsevier Ltd. Software availability Name of software: MODFLOW-OWHM (OneWater Hydrologic Flow Model) Developers: USGS Integrated Hydrologic Model Development Team Contact address: U.S. Geological Survey, Water Resources Discipline, 4165 Spruance Road, Suite 200, San Diego, CA 92101 Attention: Randall T. Hanson, Email: [email protected] Software inquires: [email protected] Availability and Online Documentation: Free download with manual and supporting material at: http://water.usgs. gov/ogw/modflow-owhm/ Online Manual available at: http://water.usgs.gov/ogw/modflowowhm/Guide/index.html Schmid), [email protected], (S.A. Leake), jdhughes@usgs. ). Year first available: 2014 (Revision 1.00) Hardware required: Windows or Unix/Linux compatible platform Software required: Windows OS or Unix/Linux OS Programming language: Fortran and C++ Program size: 9.9 MB