Mildura sits on complex Quaternary alluvium from the Murray River system. The surface clays look firm in summer. They soften fast after irrigation or rain. This shrink-swell behaviour wrecks conventional footings. Stone column design bypasses the problem entirely. We install compacted gravel columns through the reactive zone into competent bearing strata below. Load transfers directly to the columns. The surrounding soil gets densified in the process. For Mildura’s horticultural packing sheds and wine storage facilities, where differential settlement cannot exceed millimetres, the technique works. We verify column performance with in-situ permeability testing when groundwater conditions near the river influence the drainage path. The Murray Basin geology demands solutions that account for both vertical and lateral variability across the site.
A well-designed stone column grid can reduce post-construction settlement by 60 to 80 percent compared to untreated Mildura alluvial clay.
