The efficiency of hydrotransportation is determined primarily by the coarseness of the transported materials, their abrasiveness, the possibility of achieving high concentrations and easy water removal. When increasing the concentration, for example, from 10 to 30 % for coal, the energy consumption alone decreases approximately twice, taking into account specific costs per 1 tonne of cargo. The degree of efficiency of moving materials of different coarseness by this type of transport can be judged roughly by the data typical for modern practice; the costs of moving the same amount of material of classes 0-0,5; 0,5-1; 1-3 and 10-70 mm per 1 ton-km are treated as 1 : 2 : 3,5 : 10. It should be taken into account that technological transport is finally evaluated according to the main technical and economic indicators of production.