Dayton, Ohio and its environs obtain most of their water from wells which penetrate highly productive glacial-outwash deposits underlying the Great Miami River and its tributaries and receive recharge by induced streambed leakage. Combined municipal and industrial use of ground water in the 90-square-mile area has increased from about 180 cubic feet per second in 1960 to nearly 250 cubic feet per second in 1972. The increased pumpage has resulted in continuing water-level declines in some parts of the area.
A digital model which uses a finite-difference approximation technique to solve partial differential equations of flow through a porous medium was used to evaluate the effects of pumping stresses on water levels. The simulated head values presented in map form generally are in good agreement with potentiometric-surface maps prepared from field measurements.