EMPIRICAL EQUATIONS OF GROUNDWATER RECHARGE PATTERNS.

Equations of both the temporal and spatial patterns of groundwater recharge were derived empirically by analyzing sample data on saturated zone thickness using a least-squares curvilinear regression technique. The temporal pattern for the study period conforms with the prevailing rainfall regime and is optimally described by fourth-degree polynomial regression equations. The spatial pattern is optimally described by quadratic equations and suggests that an almost uniformly thick annual groundwater recharge zone of about 2. 4 m overlies the gross spatial distribution of saturated zone thickness from the major river channel to the major water divide.