A drainage pump is primarily intended for pumping surface water and seepage to different locations, and for the pumping of groundwater. Wastewater pumps on the other hand are primarily used to dispose of wastewater. This includes e.g. pumping wastewater out of collector shafts and pumping station applications.
The two pump construction types differ primarily in terms of free passage, i.e. the maximum permissible particle size of the solids contained in the wastewater. Wastewater pumps generally have larger free passage then drainage pumps.