AbstractCavity wells are shallow wells without strainers and are installed in confined aquifers. These wells are commonly installed in alluvial tracts in the Indian subcontinent, and can be used as discharge as well as recharge wells. However, during recharge, the value of aquifer parameters may change. This study was undertaken to address these changes. A cavity well was developed in a simulated circular sand tank model of a confined aquifer. The cavity thus developed was observed to be a part of a hemisphere. An analytical solution of the hydraulics of this cavity well was developed. The well was initially discharged and then recharged at various rates, and experimental data on drawdown and rise of head were collected. Aquifer parameters were calculated by substituting these data in the analytical solution. It was observed that during recharge through the well, the hydraulic conductivity and specific storage coefficient of the aquifer decreased by 15% and 13%, respectively in relation to those of discharge. Also, the aquifer parameters were found to be least affected with the change in rate of recharge or discharge.
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