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Semi Confined Aquifers - Constank discharges
In field conditions, in many cases aquifers are in semiconfined state because of
leakage from the overlying impervious body. In such cases, Hantush and Jacob
equation (as in Todd, 1995) is used. The equation is given below :
W (u, r/L) is the well function, values of which are given by Hantush for practical
field situations and the table indicating different values are given in the Text Book.
Different sets of equations are available for different disposition of aquifers or
field situation i.e. unconfined aquifers, confined aquifer, partially penetrating wells,
leaky aquifers, steady or unsteady sate etc. Computer softwares are now a
days used to avoid rigorous mathematical calculations.
Assessment of Groundwater
Groundwater can be compared to liquid mineral like petroleum. While
petroleum occurs at suitable geological structures and is not renewable,
groundwater occurs in groundwater basins as a vast natural underground
reservoir which is replenished annually. Thus, a petroleum reserve can be
