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Potential Groundwater Recharge for the State of Minnesota Using the Soil-Water-Balance Model, 1996–2010

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Potential Groundwater Recharge for the State of Minnesota Using the Soil-Water-Balance Model, 1996–2010 Prepared in cooperation with the Minnesota Pollution Control Agency Potential Groundwater Recharge for the State of Minnesota Using the Soil-Water-Balance Model, 1996–2010 Scientific Investigations Report 2015–5038 U.S. Department of the Interior U.S. Geological Survey Cover. Map showing mean annual potential recharge rates from 1996−2010 based on results from the Soil-Water-Balance model for Minnesota. Potential Groundwater Recharge for the State of Minnesota Using the Soil-Water- Balance Model, 1996–2010 By Erik A. Smith and Stephen M. Westenbroek Prepared in cooperation with the Minnesota Pollution Control Agency Scientific Investigations Report 2015–5038 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2015 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod/. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Smith, E.A., and Westenbroek, S.M., 2015, Potential groundwater recharge for the State of Minnesota using the Soil-Water-Balance model, 1996–2010: U.S. Geological Survey Scientific Investigations Report 2015–5038, 85 p., http://dx.doi.org/10.3133/sir20155038. ISSN 2328-0328 (online) iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................2 Purpose and Scope ..............................................................................................................................3 Previous Studies ...................................................................................................................................3 Model Description .........................................................................................................................................3 Model Limitations and Assumptions .................................................................................................5 Model Description and Inputs .....................................................................................................................5 Meteorological Data (Precipitation, Temperature, and Snowmelt) .............................................7 Land Cover .............................................................................................................................................7 Hydrologic Soil Groups ........................................................................................................................7 Available Soil-Water Capacity ............................................................................................................9 Lookup Tables and Control File ...........................................................................................................9 Model Calibration.........................................................................................................................................12 Parameter Estimation .........................................................................................................................12 Hydrograph Separation Comparisons .............................................................................................18 Potential Groundwater Recharge Estimates ...........................................................................................24 Annual Mean Potential Recharge Estimates .................................................................................24 Mean Annual Potential Recharge Estimates .................................................................................25 Comparison to the Regional Regression Recharge Model ..........................................................29 Comparison to Other Recharge Estimates .....................................................................................29 Sensitivity Analysis ......................................................................................................................................34 Summary........................................................................................................................................................38 Acknowledgments .......................................................................................................................................38 References Cited..........................................................................................................................................38 Appendix 1. Control File for the Minnesota Soil-Water-Balance Model ............................................44 Appendix 2. Model Calibration Analysis ..................................................................................................50 Appendix 3. Annual Mean Potential Recharge Estimates, 1996–2010 ................................................69 Appendix 4. Regional Regression Recharge, 1971–2000 .......................................................................85 Figures 1. Diagram of the interaction between the Soil-Water-Balance model code and input data .................................................................................................................................................6 2. Map showing mean annual gross precipitation in Minnesota at a 1-kilometer resolution, 1996−2010 ...................................................................................................................8 3. Map showing land cover in Minnesota at a 1-kilometer resolution, from the 2006 National Land Cover Database .................................................................................................10 4. Map showing hydrologic soil groups in Minnesota at a 1-kilometer resolution based on the merged Soil Survey Geographic and the State Soil Geographic databases .....................................................................................................................................11 5. Map showing available soil-water capacity in Minnesota at a 1-kilometer resolution based on the Geographic and the State Soil Geographic databases .............13 iv 6. Map showing watersheds with continuous streamflow data from 1996−2010 used for calibration of the Soil-Water-Balance model ..................................................................17 7. Graphs showing relation between 15-year mean base-flow estimates from three different hydrograph separation techniques and the 15-year mean potential recharge estimates from the Soil-Water-Balance model for 35 selected watersheds, along with linear trendline .................................................................................23 8. Graphs showing relation between annual mean base-flow estimates from three different hydrograph separation techniques and the annual mean potential recharge estimates from the Soil-Water-Balance model for 35 selected watersheds, along with linear trendline .................................................................................24 9. Map showing mean annual potential recharge rates from 1996−2010 based on results from the Soil-Water-Balance model for Minnesota ................................................26 10. Map showing locations of point and regional recharge estimates referred to in text and table 9 ....................................................................................................................................27 11. Histogram of the mean annual potential recharge rates from the Soil-Water-Balance model from 1996−2010 for Minnesota .................................................28 12. Graph showing relation between mean annual gross precipitation and the mean annual potential recharge estimates from the Soil-Water-Balance model for the overall calibration period (1996−2010) for the 35 selected watersheds used for model calibration ........................................................................................................................29 13. Map showing mean annual potential recharge estimates from the Soil-Water-Balance model, shown as a percentage of mean annual gross precipitation from 1996−2010 ....................................................................................................30 14. Map showing difference between mean annual potential recharge estimates from the Soil-Water-Balance model for 1996−2010 and recharge estimates from the regional regression recharge model for 1971−2000 ..............................................................32 3–1. Map showing annual mean potential recharge for 1996, based on results from the Minnesota Soil-Water-Balance model ...................................................................................70 3–2. Map showing annual mean potential recharge for
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