Freeze-Thaw Effects on Soils Treated for Water Repellency

Abstract

Water can be supplied to many arid areas by harvesting the precipitation that falls on artificially prepared water-repellent soil catchments. The failure, in 1973, of wax-treated water harvesting catchment led to this study which indicates that the failure was due to swelling and shrinking of the treated soil which caused complete structural breakdown and loss of repellency. The laboratory freeze-thaw studies demonstrated that the smoother the plot, the less chance of freeze-thaw damage. Generally, coarser-textured soil can withstand freeze-thaw cycles better than finer-textured soils. Soil properties, other than texture, may also affect resistance to damage by freeze-thaw cycles. Increasing the repellent application rate may improve resistance to breakdown.