Potable water treatment
Potable water treatment

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Potable water treatment

2.9 Percolation

Movement of infiltrated water downwards through the zone of aeration (Figure 5) is known as percolation. The infiltrated water which does not remain held by capillary forces in the surface soils moves by the action of gravity through the unsaturated layers of soil or rock until it arrives at the water table. Here the percolated water joins the body of groundwater which seeps slowly to the sea.

Figure 5
Figure 5 Zones of subsurface water

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