Groundwater control is a fundamental part of many construction or mining projects where excavation must be made below groundwater level.

Groundwater control can be achieved by pumping (where groundwater levels are temporarily lowered to allow excavation) or by exclusion methods (where low permeability cut-off walls are used to keep water out of the excavation).
Several methods can be used for groundwater control by pumping (commonly known as dewatering). The most common types of groundwater control by pumping are – in order of sophistication: sump pumping, wellpoints, deep wells and eductor wells.