<p>Accurately estimating groundwater flow velocity is crucial for water resource management, contaminant transport assessments, and various hydrogeological applications. Numerous field studies, laboratory tests, and computer simulations are performed to examine fluid flow in porous media and multiple flow regimes in aquifers. Researchers have yet to develop a single, simple, environmentally friendly, and cost-effective method for measuring subsurface flow velocity. Therefore, this study employed laboratory experiments and numerical modeling to quantify horizontal groundwater flux in an aquifer and flow velocity across a perforated borehole that penetrated the aquifer. A laboratory setup was designed to simulate a confined aquifer system, incorporating a perforated borehole under controlled flow conditions. A corresponding two-dimensional numerical model was then developed to represent the horizontal cross-section of the aquifer–borehole system. The numerical framework combines three types of steady state flow: (1) slow flow within the porous media given by Darcy’s law, (2) high-velocity flow within the borehole, which is formulated as the Navier-Stokes equation, and (3) transitional flow in the interfacial zone between the aquifer and the borehole given by the Brinkman equation. Model outputs were compared against experimental observations, demonstrating good agreement and validating each other’s results. This study integrated experimental and numerical approaches to quantify groundwater flow velocity in confined aquifers.</p>