- Soil hydrophobia, or water repellency, in the coarse sand typical of the Swan Coastal Plain in Perth in Western Australia is common, leading to reduced water infiltration. The main practice recommended to alleviate water repellency is the use of wetting agents, most of which are surfactant-based. Five commercial wetting agents were evaluated for their effects on water infiltration into samples of native sandy soils. Capillary rise and double-ring infiltrometer methods were used for this purpose. The infiltration of water was somewhat improved with the application of wetting agents, but this was short-lived and, when measured a few days later, was similar to or lower than the infiltration in the untreated sand. These findings raise questions on the efficiency of surfactant-based wetting agents to treat water-repellent soils. Further investigation into the interaction and adsorption between surfactants and soil particles is needed.