Figure 6.
The graph depicts drawdown in metres on the y-axis from 0 to 20 and hydraulic conductivity in metres per second on the x-axis from 10 to the power negative 8 to 10 to the power negative 1. Shaded zones indicate single-stage wellpoints, two-stage wellpoints, Deepwells, Ejectors, and Sump. Notes state Dewatering may not be feasible or necessary at low conductivity, and Physical cut off necessary at high conductivity. Project case studies are shown as points for Wellpoints, Deepwells, and Ejectors across the chart.Range of application of dewatering techniques with supporting empirical data, after Roberts and Preene (1994). In the original figure the horizontal axis is labelled ‘Permeability’ rather than ‘Hydraulic conductivity’