Unconfined Aquifer Flow Theory - from Dupuit to present

TL;DR

This paper reviews the historical development and recent advances in analytical solutions for unconfined aquifer flow, highlighting the evolution from Dupuit's early work to modern coupled models.

Contribution

It provides a comprehensive overview of the progression of unconfined aquifer flow solutions, emphasizing recent efforts to incorporate vadose zone coupling for improved realism.

Findings

Analytical solutions have evolved from Dupuit to Neuman's models.

Recent research focuses on coupling aquifer and vadose zone dynamics.

Despite advances, realistic simulation of aquifer tests remains challenging.

Abstract

Analytic and semi-analytic solution are often used by researchers and practicioners to estimate aquifer parameters from unconfined aquifer pumping tests. The non-linearities associated with unconfined (i.e., water table) aquifer tests makes their analysis more complex than confined tests. Although analytical solutions for unconfined flow began in the mid-1800s with Dupuit, Thiem was possibly the first to use them to estimate aquifer parameters from pumping tests in the early 1900s. In the 1950s, Boulton developed the first transient well test solution specialized to unconfined flow. By the 1970s Neuman had developed solutions considering both primary transient storage mechanisms (confined storage and delayed yield) without non-physical fitting parameters. In the last decade, research into developing unconfined aquifer test solutions has mostly focused on explicitly coupling the aquifer with the linearized vadose zone. Despite the many advanced solution methods available, there still exists a need for realism to accurately simulate real-world aquifer tests.