Due to the design of the hydraulic part and the quality of the components used, submersible drainage pumps are designed for the most difficult working conditions, such as drainage of excavations, drainage ditches, land drainage, pumping heavy sludge and dirty water. Due to the increased wear resistance of key components such as the hydraulic part and the sealing, the equipment can pump water with contaminants such as silt, bentonite, clay, gravel, sand, fibrous debris and slurry. Some models have an agitator mounted at the end of the shaft. The agitator is a specially constructed impeller which, before the pump inlet, intensively mixes sludge, sand and sediment with the water, thanks to which heavy solids and sediment are easily pumped out as a suspension. Submersible pumps in this category are specifically designed to be used by experienced customers.