Radius of Influence Calculator

by Glenn M. Duffield, President, HydroSOLVE, Inc.

The radius of influence for a pumping well in an infinite nonleaky confined aquifer is given as follows (Bear 1979):

R(t) = 1.5 \sqrt{T t / S}

where R(t) is radius of influence [L], T is transmissivity [L²/T], t is time [T], and S is storativity [dimensionless].