Stream-floodwave propagation through the Great Bend alluvial aquifer, Kansas: Field measurements and numerical simulations

摘要: Abstract The hypothesis is explored that groundwater-level rises in the Great Bend Prairie aquifer of Kansas are caused not only by water percolating downward through soil but also pressure pulses from stream flooding propagate a translatory motion numerous high hydraulic diffusivity buried channels crossing an approximately west to east direction. To validate this hypothesis, two transects wells north-south and east-west orientation alongside some paleochannels area were instrumented with water-level-recording devices; streamflow data all streams obtained available stream-gaging stations. A theoretical approach was developed conceptualize numerically stream-aquifer processes. field numerical simulations provided support for hypothesis. Thus, observation located along shoulders or between inferred show little no fluctuations correlations streamflow, whereas water-level good correlation streamflows connected site means paleochannels. simulation results demonstrate larger aquifer, extent pulse propagation faster speed. conceptual indicate long-distance floodwaves (of order tens kilometers) indeed feasible plausible parameters. sensitivity analysis speed more sensitive variations roughness (Manning's coefficient) channel slope than any parameter.