Determination of Aquitard/Aquiclude Hydraulic Properties from Arbitrary Water‐Level Fluctuations by Deconvolution

A deconvolution method is proposed for the estimation of aquitard/aquiclude vertical hydraulic diffusivities on the basis of water‐level measurements in piezometers completed both in the confining layer(s) and in neighboring aquifers. The water levels may fluctuate in an arbitrary manner which is not necessarily caused by a prescribed pumping regime (as required in conventional pumping tests). A simple formula from the literature can be used to correct the measured water levels for time lag in the piezometer response. If the specific storage of the confining material is known from laboratory consolidation tests, the hydraulic diffusivity estimates can be translated into vertical hydraulic conductivities. The method is illustrated with the aid of a case study from southern California and is shown to yield robust parameter estimates.