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The water table roughly follows the contour of the overlying land surface, and rises and falls with rainy or dry weather. Springs and oases occur when the water table reaches the surface. Springs commonly form on hillsides, where the earth's slanting surface may "intersect" with the water table. Other, unseen springs are found under rivers and lakes, and account for the sometimes surprisingly well-preserved water levels which occur in times of mild drought.

The practice of drilling wells to extract groundwater is dependent on understanding the water table. Because wells must reach the water table, its depth determines the minimum depth of a viable well, and thus the feasibility of drilling it.