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A numerical scheme is developed to estimate quantitatively parameters related to geohydrological and hydrological characteristics of groundwater aquifers, employing historic data of hydraulic head, rainfall, pumpages, etc. The scheme is based upon the constrained minimisation of the sum of the squares of the residues in the Boussinesq equation. Derivatives of hydraulic head are estimated by the least-squares polynomial approximation.

An optimization model for computer-assisted estimation of aquifer parameters has been developed. It is based upon the principle of minimization of the sum of squares of the differences between observed and computed drawdowns. The objective strategy eliminates the subjectivity associated with the conventional curve-matching procedures. Apart from the parameter estimation, the model can assist in identifying certain hydrogeological features like leakage, discontinuities, vertical anisotropy, etc. It also can provide a check on consistency among different data sets monitored during a test pumping (e.g., drawdown and recovery data). The application of the proposed model has been illustrated by analysis of field data. The model-computed parameters honored the observed data more closely than the graphical estimates. The model could also identify leakage as the cause of departure of the time-drawdown curve from the Theis type curve. In another study, the model results lead to an inference that the recovery data of the pumped well are inconsistent with the rest of the data.