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Constant-head test

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Constant-head test

Constant-head test


1. Aquifers of infinite lateral extent


aquifer is confined, isotropic, of infinite lateral extent;

two leakage concepts can be considered: accounting and not accounting for leakage;

drawdown is estimated in the aquifer at any distance from the pumping well;

hydraulic head in the pumping well is constant during the test period;

storage capacity of the pumping well is included.



a        b        c

Conceptual model sketches for constant-head test analysis: nonleaky confined aquifer (a); leaky confined aquifer (b ); unconfined aquifer (c). For leaky aquifer some other positions of aquifers and aquitards can be considered.



2. Radially heterogeneous aquifer


general conditions for constant-head tests in nonleaky and leaky aquifers of infinite lateral extent;

a circular boundary along the external contour of the aquifer;

the pumping well is located in the center of the circular aquifer.


Radially heterogeneous aquifer: cross-section and plan view



Pumping regimes:

One well pumped at a constant drawdown




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