An Evaluation of the Guelph Permeameter for Measuring Saturated Hydraulic Conductivity

A study was conducted to compare saturated hydraulic conductivity (Kg) measurements using the Guelph permeameter, the falling head permeameter and the single auger hole method on soils with textures ranging from clay to loamy sand. Measurements at six sites showed that in 21 out of 23 cases, the falling head permeameter yielded lower values than the Guelph permeameter. The overall geometric mean was 1.3590 cm/h for the Guelph permeameter and 0.0328 cm/h for the falling head permeameter. This was attributed to the smaller soil sample volume of the falling head permeameter method, soil structural changes within the cores, and soil anisotropy. In two of three situations, the auger hole method produced higher Kg values than the Guelph permeameter. The overall geometric mean was 0.1257 cm/h for the Guelph permeameter and 0.7721 cm/h for the auger hole method. It is believed that the larger volume of soil sampled by the auger hole method, the layering of the soil profile, and the direction of water flow are responsible for the higher Kg values obtained with the auger hole method.