Drawdowns for Nonleaky Aquifer Flow with Storage in Finite‐Width Sink

Abstract

One-dimensional horizontal flow in a semi-infinite confined aquifer can be described in terms of mathematical solutions that relate the drawdown to aquifer parameters and the aquifer flow rate. A new analytical solution, that considers the effects of storage in a finite-width sink into which flow occurs from the aquifer, was developed for the nonleaky aquifer case. The solution is written in the form of exponential and complementary error functions, and a drain function is defined based on the solution. A type curve for the drain function is plotted, and aquifer parameters can be determined by matching drawdown data from observation wells to the type curve. Applications of this drain function and type-curve matching procedure would include analyzing aquifer drawdowns resulting from a canal pumping test, in which a significant part of the discharge from the canal was derived from water stored in the canal as well as from discharge from a nonleaky aquifer into the canal.