Unsteady Drawdown in 2-D Water Table Aquifer

The inclusion of vertical velocity effects results in integral solutions to the linearized problem of instantaneous and time-dependent drawdown in water table aquifers. The solutions are shown to be the same as those of Stallman and Hantush for the limiting conditions of small drawdown in shallow aquifers. The theory is subjected to verification using test results from drawdown in a sand model. The tests show that the inclusion of vertical velocity effects alone is insufficient for substantial progress in unsteady water table drawdown theory. The tests further suggest that inclusion of time-dependent pore drainage will be required for progress in that theory. For this reason, the sand model drawdown data are presented as a more realistic test of water table drawdown theory than are data from a Hele-Shaw apparatus.