The backfill materials around under-ground power cables affect the maximum current carrying capacity of these cables. Usually backfill soils around under-ground power cables lose their moisture content, forming dry zones around the cables and leading to an increase in the thermal resistance and decreasing in maximum current carrying capacity. But according to the results of the experimental works which are carried out in this paper, it is noticed that some types of soil lost their moisture content faster than the other. This means that the dry zone around the cable in some soils form faster than the others. The aim of this paper is to determine the best type of artificial soil that can be used as backfill material to minimize the effect of dry zones that cause thermal failure to the cable insulation.