Description
This video shows a cross section with an unconfined aquifer, an aquitard shown in gray, and an underlying confined aquifer. The confined aquifer is pumped and drawdown in four wells is displayed both in cross section and as graphs of drawdown versus time for three situations. First for an impermeable aquitard, then for an aquitard that transmits groundwater flow but does not store water, and finally for an aquitard that is permeable and stores water. (2 minutes)
A discussion of aquifer testing is provided in the Groundwater Project book “An Introduction to Hydraulic Testing in Hydrogeology” that can be downloaded for free as a PDF.
The updated version of the video corrects the audio narrative in the presentation of an aquitard that transmits but does not store water, noting that, in the theoretical, infinite, aquifer system, the unconfined drawdown continues indefinitely at an ever-slower rate as the area of leakage expands. The artistic liberties taken with the animation of the drawdown cones and graphs of unconfined drawdown with time in the original video were adjusted to more accurately depict natural systems and be internally consistent.
Citation: Santi, P. & Poeter, E. (2024). Aquifer Testing: Conceptual, Confined & Leaky. Video of The Groundwater Project, Guelph, Ontario, Canada.