Mathematical Model of Leaky Aquifer

A description is given for a technique to determine the direction and volume of leakage between a confined aquifer and an overlying unconfined aquifer. The technique involves the numerical modeling of only the unconfined aquifer, so that data are required on only this aquifer. The predicted values of water table elevation obtained from the numerical model are compared to known values. From discrepancies between these values, inferences can be made on the direction and volume of leakage. The results of the application of the technique in the Kiowa-Bijou basin of Colorado are given. Even with poor input data to the model the results obtained on the direction of leakage are good, but the accuracy of the estimate of the volume of leakage demands more on the accuracy of the input data.