Clay delving in South Australia helps mix sandy topsoil with clay subsoil, improving water distribution in the soil. By bringing clay to the surface, delving reduces water flow patterns and allows for deeper, more even wetting of the soil. This method also decreases water ponding at the boundary between topsoil and subsoil, promoting better water penetration into the deeper layers. The effectiveness of delving varies depending on soil characteristics and equipment used, with closer tine spacing leading to more uniform wetting.