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Seepage pressures are part of the neutral or nondeformative stresses acting in a groundwater basin. The reduction of these pressures gives rise to a stress transfer from neutral to effective. The increase in effective stresses is, exclusively responsible for measurable deformations of the land surface. The amount of land subsidence or groundwater recovery from compressible confining layers depends upon the specific storage of the strata and the average head change within them. Expressions for the specific storage are obtained from both consolidation theory and conservation principles of compressible flow. Average head changes are identified on a depth-pressure diagram in terms of head changes in adjacent aquifers and are referred to as ‘effective-pressure areas.’ The geometry of the effective-pressure area is shown to depend upon the thickness of the compressible strata, the magnitude of artesian pressure decline, the manner in which the basin is developed, and time. These factors are embodied in equations that quantitatively describe the release of stored water from compressible confining layers resulting from their vertical compression in areas of land subsidence.