ABSTRACT
This chapter outlines some available methods for control of surface water and groundwater. Dewatering methods control groundwater by pumping, effecting a local lowering of groundwater levels. One of the attractive characteristics of the exclusion technique is that it allows work to be carried out below groundwater level with minimal effects on groundwater levels outside the site. Photograph looking down into the base of a shaft, lined by contiguous concrete piles. Groundwater is being controlled by sump pumping, but the excavator and workmen in the base of the shaft are working in very wet and muddy conditions. Shaft is sunk below groundwater level in relatively stable ground conditions. Vertical relief wells in the base of the shaft allow water to flow into the base of the shaft, driven by groundwater levels in the surrounding ground. Applicable range of groundwater lowering methods for different combinations of permeability and drawdown.
