Oimulated (ground-Water how and Oources oi Water in the IxillbucK L/reek Vallei| near Wooster, Waijne L/ountij, (Jhio By K.J. BREEN, A. L KONTIS, G.L ROWE, AN<| RJ. U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 94-4131 Columbus, Ohio 1995 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY GORDON P. EATON, Director For additional information Copies of this report may write to: be purchased from: District Chief U.S. Geological Survey U.S. Geological Survey Earth Science Information Center 975 West Third Avenue Open-File Reports Section Columbus, OH 43212-3192 Box 25286, MS 517 Denver Federal Center Denver, CO 80225 CONTENTS Abstract.......................................................................................................................................................................1 Introduction.................................................................................................................................................................2 Purpose and scope ...............................................................................................................................................2 Location and hydrogeologic setting ....................................................................................................................6 Previous investigations .......................................................................................................................................7 Acknowledgments ..............................................................................................................................................8 Approach.....................................................................................................................................................................8 Ground-water flow ..............................................................................................................................................8 Streamflow gain and loss .................................................................................................................................. 11 Chemical and isotopic data ............................................................................................................................... 12 Simulated ground-water flow ...................................................................................................................................13 Modeling strategy .............................................................................................................................................15 Steady-state simulation ..............................................................................................................................15 Transient simulation ..................................................................................................................................19 Simulation of recharge by Variable-Recharge procedure ................................................................................. 19 Model design .....................................................................................................................................................23 Model grid and lateral boundaries .............................................................................................................23 Vertical discretization ................................................................................................................................24 Model input .......................................................................................................................................................24 Boundary fluxes and pumping rates ..........................................................................................................24 Variable recharge data ...............................................................................................................................26 Water available for recharge ..............................................................................................................26 Land-surface elevation .......................................................................................................................26 Upland variable-recharge zones .........................................................................................................26 Reduction of water available for recharge and runoff in urban areas ................................................26 Disposition of upland runoff ..............................................................................................................28 Hydraulic properties of streams and drains ................................................................................................28 Hydraulic conductivity and vertical leakage .............................................................................................31 Transient simulation data...........................................................................................................................31 Model calibration .............................................................................................................................................32 Steady-state calibration ..............................................................................................................................33 Simulated steady-state head distribution and flowpaths ....................................................................37 Transient calibration ..................................................................................................................................38 Validity of the ground-water-flow model ..................................................................................................38 Sources of water in the Killbuck Creek valley ........................................................................................................40 Infiltration of streamwater ................................................................................................................................40 Results of seepage studies .........................................................................................................................41 Tributary streams ................................................................................................................................41 Killbuck Creek....................................................................................................................................41 Results of chemical and isotopic studies ...................................................................................................42 Water in and beneath Killbuck Creek ................................................................................................42 Freshet of February 1985 and streamwater in the stratified drift .......................................................46 Results of steady-state flow simulation .....................................................................................................49 Simulated stream gains and losses .....................................................................................................49 Flow to drains .....................................................................................................................................49 Recharge at land surface derived from local precipitation ...............................................................................50 Recharge from precipitation on the valley floor ........................................................................................50 Redirected upland runoff ...........................................................................................................................51 Spatial distribution of recharge at land surface from all sources ...............................................................54 Contents III Lateral flow from uplands to valley ..................................................................................................................54 Results of chemical and isotopic studies ...................................................................................................54 Results of steady-state simulation of flow to valley ..................................................................................60 Simulated steady-state ground-water budgets ..................................................................................................62 Summary ...................................................................................................................................................................64 References cited........................................................................................................................................................68 Supplemental data ....................................................................................................................................................71 PLATES [Plates are in pocket] Plate 1-8. Map showing: 1. Network of data-collection sites and line-of-section A-A' 2. Model grid, variable-recharge zones, and location of various features simulated by steady-state ground-water-flow model 3. Contours of land-surface elevation array used in Variable-Recharge procedure and location of simulated recharge and seepage areas steady-state model 4. Ground-water-flow model calibration zones used to generate hydraulic conductivity